A series of oxidative reactions in the breakdown of acetyl units derived from GLUCOSE; FATTY ACIDS; or AMINO ACIDS by means of tricarboxylic acid intermediates. The end products are CARBON DIOXIDE, water, and energy in the form of phosphate bonds.
A key intermediate in metabolism. It is an acid compound found in citrus fruits. The salts of citric acid (citrates) can be used as anticoagulants due to their calcium chelating ability.
"Citrates, in a medical context, are compounds containing citric acid, often used in medical solutions for their chelating properties and as a part of certain types of nutritional support."
"Malate" is a term used in biochemistry to refer to a salt or ester of malic acid, a dicarboxylic acid found in many fruits and involved in the citric acid cycle, but it does not have a specific medical definition as such.
An enzyme of the oxidoreductase class that catalyzes the conversion of isocitrate and NAD+ to yield 2-ketoglutarate, carbon dioxide, and NADH. It occurs in cell mitochondria. The enzyme requires Mg2+, Mn2+; it is activated by ADP, citrate, and Ca2+, and inhibited by NADH, NADPH, and ATP. The reaction is the key rate-limiting step of the citric acid (tricarboxylic) cycle. (From Dorland, 27th ed) (The NADP+ enzyme is EC 1.1.1.42.) EC 1.1.1.41.
Derivatives of OXALOACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that include a 2-keto-1,4-carboxy aliphatic structure.
An enzyme that catalyzes the reversible hydration of fumaric acid to yield L-malic acid. It is one of the citric acid cycle enzymes. EC 4.2.1.2.
An enzyme that catalyzes the reversible hydration of cis-aconitate to yield citrate or isocitrate. It is one of the citric acid cycle enzymes. EC 4.2.1.3.
A family of compounds containing an oxo group with the general structure of 1,5-pentanedioic acid. (From Lehninger, Principles of Biochemistry, 1982, p442)
An intermediate compound in the metabolism of carbohydrates, proteins, and fats. In thiamine deficiency, its oxidation is retarded and it accumulates in the tissues, especially in nervous structures. (From Stedman, 26th ed)
The Ketoglutarate Dehydrogenase Complex is a multi-enzyme complex involved in the citric acid cycle, catalyzing the oxidative decarboxylation of alpha-ketoglutarate to succinyl-CoA and CO2, thereby connecting the catabolism of amino acids, carbohydrates, and fats to the generation of energy in the form of ATP.
A dicarboxylic acid ketone that is an important metabolic intermediate of the CITRIC ACID CYCLE. It can be converted to ASPARTIC ACID by ASPARTATE TRANSAMINASE.
An enzyme that catalyzes the conversion of (S)-malate and NAD+ to oxaloacetate and NADH. EC 1.1.1.37.
Enzyme that catalyzes the first step of the tricarboxylic acid cycle (CITRIC ACID CYCLE). It catalyzes the reaction of oxaloacetate and acetyl CoA to form citrate and coenzyme A. This enzyme was formerly listed as EC 4.1.3.7.
Acetyl CoA participates in the biosynthesis of fatty acids and sterols, in the oxidation of fatty acids and in the metabolism of many amino acids. It also acts as a biological acetylating agent.
A water-soluble, colorless crystal with an acid taste that is used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters. It is also used in foods as a sequestrant, buffer, and a neutralizing agent. (Hawley's Condensed Chemical Dictionary, 12th ed, p1099; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1851)
Stable carbon atoms that have the same atomic number as the element carbon, but differ in atomic weight. C-13 is a stable carbon isotope.
Pyruvates, in the context of medical and biochemistry definitions, are molecules that result from the final step of glycolysis, containing a carboxylic acid group and an aldehyde group, playing a crucial role in cellular metabolism, including being converted into Acetyl-CoA to enter the Krebs cycle or lactate under anaerobic conditions.
A flavoprotein containing oxidoreductase that catalyzes the dehydrogenation of SUCCINATE to fumarate. In most eukaryotic organisms this enzyme is a component of mitochondrial electron transport complex II.
Derivatives of ACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxymethane structure.
Glyoxylates are organic compounds that are intermediate products in the metabolic pathways responsible for the breakdown and synthesis of various molecules, including amino acids and carbohydrates, and are involved in several biochemical processes such as the glyoxylate cycle.
Enzymes that catalyze the first step leading to the oxidation of succinic acid by the reversible formation of succinyl-CoA from succinate and CoA with the concomitant cleavage of ATP to ADP (EC 6.2.1.5) or GTP to GDP (EC 6.2.1.4) and orthophosphate. Itaconate can act instead of succinate and ITP instead of GTP.EC 6.2.1.-.
Derivatives of acetic acid with one or more fluorines attached. They are almost odorless, difficult to detect chemically, and very stable. The acid itself, as well as the derivatives that are broken down in the body to the acid, are highly toxic substances, behaving as convulsant poisons with a delayed action. (From Miall's Dictionary of Chemistry, 5th ed)
The complex series of phenomena, occurring between the end of one CELL DIVISION and the end of the next, by which cellular material is duplicated and then divided between two daughter cells. The cell cycle includes INTERPHASE, which includes G0 PHASE; G1 PHASE; S PHASE; and G2 PHASE, and CELL DIVISION PHASE.
Compounds based on fumaric acid.
Derivatives of SUCCINIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a 1,4-carboxy terminated aliphatic structure.
A metabolic process that converts GLUCOSE into two molecules of PYRUVIC ACID through a series of enzymatic reactions. Energy generated by this process is conserved in two molecules of ATP. Glycolysis is the universal catabolic pathway for glucose, free glucose, or glucose derived from complex CARBOHYDRATES, such as GLYCOGEN and STARCH.
Derivatives of GLUTAMIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the 2-aminopentanedioic acid structure.
Biosynthesis of GLUCOSE from nonhexose or non-carbohydrate precursors, such as LACTATE; PYRUVATE; ALANINE; and GLYCEROL.
The metabolic substances ACETONE; 3-HYDROXYBUTYRIC ACID; and acetoacetic acid (ACETOACETATES). They are produced in the liver and kidney during FATTY ACIDS oxidation and used as a source of energy by the heart, muscle and brain.
Salts and esters of the 7-carbon saturated monocarboxylic acid heptanoic acid.
An important enzyme in the glyoxylic acid cycle which reversibly catalyzes the synthesis of L-malate from acetyl-CoA and glyoxylate. This enzyme was formerly listed as EC 4.1.3.2.
A biotin-dependent enzyme belonging to the ligase family that catalyzes the addition of CARBON DIOXIDE to pyruvate. It is occurs in both plants and animals. Deficiency of this enzyme causes severe psychomotor retardation and ACIDOSIS, LACTIC in infants. EC 6.4.1.1.
A family of organic anion transporters that specifically transport DICARBOXYLIC ACIDS such as alpha-ketoglutaric acid across cellular membranes.
A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.
A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.
Glutarates are organic compounds, specifically carboxylic acids, that contain a five-carbon chain with two terminal carboxyl groups and a central methyl group, playing a role in various metabolic processes, including the breakdown of certain amino acids. They can also refer to their salts or esters. Please note that this definition is concise and may not cover all aspects of glutarates in depth.
Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)
A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from GLUTAMIC ACID and AMMONIA. It is the principal carrier of NITROGEN in the body and is an important energy source for many cells.
Salts and derivatives of acetoacetic acid.
Enzymes that catalyze the cleavage of a carbon-carbon bond of a 3-hydroxy acid. (Dorland, 28th ed) EC 4.1.3.
The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)
'Keto acids', also known as ketone bodies, are water-soluble compounds - acetoacetic acid, beta-hydroxybutyric acid, and acetone - that are produced during fat metabolism when liver glycogen stores are depleted, providing an alternative energy source for the brain and other organs in states of carbohydrate restriction or intense physical exertion.
The chemical reactions involved in the production and utilization of various forms of energy in cells.
Product of the oxidation of ethanol and of the destructive distillation of wood. It is used locally, occasionally internally, as a counterirritant and also as a reagent. (Stedman, 26th ed)
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
A normal intermediate in the fermentation (oxidation, metabolism) of sugar. The concentrated form is used internally to prevent gastrointestinal fermentation. (From Stedman, 26th ed)
Enzymes that catalyze the breakage of a carbon-oxygen bond leading to unsaturated products via the removal of water. EC 4.2.1.
A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.
Coenzyme A is an essential coenzyme that plays a crucial role in various metabolic processes, particularly in the transfer and activation of acetyl groups in important biochemical reactions such as fatty acid synthesis and oxidation, and the citric acid cycle.
A non-essential amino acid naturally occurring in the L-form. Glutamic acid is the most common excitatory neurotransmitter in the CENTRAL NERVOUS SYSTEM.
One of the non-essential amino acids commonly occurring in the L-form. It is found in animals and plants, especially in sugar cane and sugar beets. It may be a neurotransmitter.
Derivatives of propionic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxyethane structure.
Treatment process involving the injection of fluid into an organ or tissue.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
An imperfect fungus causing smut or black mold of several fruits, vegetables, etc.
Organic compounds that are acyclic and contain three acid groups. A member of this class is citric acid which is the first product formed by reaction of pyruvate and oxaloacetate. (From Lehninger, Principles of Biochemistry, 1982, p443)
The rate dynamics in chemical or physical systems.
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)
The period from onset of one menstrual bleeding (MENSTRUATION) to the next in an ovulating woman or female primate. The menstrual cycle is regulated by endocrine interactions of the HYPOTHALAMUS; the PITUITARY GLAND; the ovaries; and the genital tract. The menstrual cycle is divided by OVULATION into two phases. Based on the endocrine status of the OVARY, there is a FOLLICULAR PHASE and a LUTEAL PHASE. Based on the response in the ENDOMETRIUM, the menstrual cycle is divided into a proliferative and a secretory phase.
A sudden, audible expulsion of air from the lungs through a partially closed glottis, preceded by inhalation. It is a protective response that serves to clear the trachea, bronchi, and/or lungs of irritants and secretions, or to prevent aspiration of foreign materials into the lungs.
The ability to detect chemicals through gustatory receptors in the mouth, including those on the TONGUE; the PALATE; the PHARYNX; and the EPIGLOTTIS.
A multienzyme complex responsible for the formation of ACETYL COENZYME A from pyruvate. The enzyme components are PYRUVATE DEHYDROGENASE (LIPOAMIDE); dihydrolipoamide acetyltransferase; and LIPOAMIDE DEHYDROGENASE. Pyruvate dehydrogenase complex is subject to three types of control: inhibited by acetyl-CoA and NADH; influenced by the energy state of the cell; and inhibited when a specific serine residue in the pyruvate decarboxylase is phosphorylated by ATP. PYRUVATE DEHYDROGENASE (LIPOAMIDE)-PHOSPHATASE catalyzes reactivation of the complex. (From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed)
Salts or esters of LACTIC ACID containing the general formula CH3CHOHCOOR.
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
The mitochondria of the myocardium.
Organic compounds containing the carboxy group (-COOH). This group of compounds includes amino acids and fatty acids. Carboxylic acids can be saturated, unsaturated, or aromatic.
Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
Mitochondria in hepatocytes. As in all mitochondria, there are an outer membrane and an inner membrane, together creating two separate mitochondrial compartments: the internal matrix space and a much narrower intermembrane space. In the liver mitochondrion, an estimated 67% of the total mitochondrial proteins is located in the matrix. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p343-4)
Agents that suppress cough. They act centrally on the medullary cough center. EXPECTORANTS, also used in the treatment of cough, act locally.
Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
A species of gram-positive bacteria that is a common soil and water saprophyte.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
The minimum concentration at which taste sensitivity to a particular substance or food can be perceived.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
A group of proteins possessing only the iron-sulfur complex as the prosthetic group. These proteins participate in all major pathways of electron transport: photosynthesis, respiration, hydroxylation and bacterial hydrogen and nitrogen fixation.
Proteins that control the CELL DIVISION CYCLE. This family of proteins includes a wide variety of classes, including CYCLIN-DEPENDENT KINASES, mitogen-activated kinases, CYCLINS, and PHOSPHOPROTEIN PHOSPHATASES as well as their putative substrates such as chromatin-associated proteins, CYTOSKELETAL PROTEINS, and TRANSCRIPTION FACTORS.
Isocitrate is a chemical compound, an isomer of citric acid, which is a key intermediate in the tricarboxylic acid cycle (Krebs cycle) and is involved in energy production through cellular respiration in living organisms.
An order of fish including smelts, galaxiids, and salamanderfish.
Aconitic Acid is a weak organic acid, naturally found in some fruits and vegetables, that metabolizes to citric acid in the body and has been used in traditional medicine but can be toxic in high concentrations.
Chemicals used mainly to disinfect root canals after pulpectomy and before obturation. The major ones are camphorated monochlorophenol, EDTA, formocresol, hydrogen peroxide, metacresylacetate, and sodium hypochlorite. Root canal irrigants include also rinsing solutions of distilled water, sodium chloride, etc.
Encysted cercaria which house the intermediate stages of trematode parasites in tissues of an intermediate host.
An alkaloid derived from the bark of the cinchona tree. It is used as an antimalarial drug, and is the active ingredient in extracts of the cinchona that have been used for that purpose since before 1633. Quinine is also a mild antipyretic and analgesic and has been used in common cold preparations for that purpose. It was used commonly and as a bitter and flavoring agent, and is still useful for the treatment of babesiosis. Quinine is also useful in some muscular disorders, especially nocturnal leg cramps and myotonia congenita, because of its direct effects on muscle membrane and sodium channels. The mechanisms of its antimalarial effects are not well understood.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.
Adherent debris produced when cutting the enamel or dentin in cavity preparation. It is about 1 micron thick and its composition reflects the underlying dentin, although different quantities and qualities of smear layer can be produced by the various instrumentation techniques. Its function is presumed to be protective, as it lowers dentin permeability. However, it masks the underlying dentin and interferes with attempts to bond dental material to the dentin.
A species of gram-negative bacteria of the family ACETOBACTERACEAE found in FLOWERS and FRUIT. Cells are ellipsoidal to rod-shaped and straight or slightly curved.
Derivatives of caproic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain a carboxy terminated six carbon aliphatic structure.
The period of cyclic physiological and behavior changes in non-primate female mammals that exhibit ESTRUS. The estrous cycle generally consists of 4 or 5 distinct periods corresponding to the endocrine status (PROESTRUS; ESTRUS; METESTRUS; DIESTRUS; and ANESTRUS).
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
The hollow, muscular organ that maintains the circulation of the blood.
The process by which the nature and meaning of gustatory stimuli are recognized and interpreted by the brain. The four basic classes of taste perception are salty, sweet, bitter, and sour.
The dynamic collection of metabolites which represent a cell's or organism's net metabolic response to current conditions.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Large bodies consisting of self-luminous gas held together by their own gravity. (From McGraw Hill Dictionary of Scientific and Technical Terms, 6th ed)
A nonreducing disaccharide composed of GLUCOSE and FRUCTOSE linked via their anomeric carbons. It is obtained commercially from SUGARCANE, sugar beet (BETA VULGARIS), and other plants and used extensively as a food and a sweetener.
Tartrates are salts or esters of tartaric acid, primarily used in pharmaceutical industry as buffering agents, and in medical laboratories for the precipitation of proteins.
A muscular organ in the mouth that is covered with pink tissue called mucosa, tiny bumps called papillae, and thousands of taste buds. The tongue is anchored to the mouth and is vital for chewing, swallowing, and for speech.
An oxidative decarboxylation process that converts GLUCOSE-6-PHOSPHATE to D-ribose-5-phosphate via 6-phosphogluconate. The pentose product is used in the biosynthesis of NUCLEIC ACIDS. The generated energy is stored in the form of NADPH. This pathway is prominent in tissues which are active in the synthesis of FATTY ACIDS and STEROIDS.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

Activities of glucose metabolic enzymes in human preantral follicles: in vitro modulation by follicle-stimulating hormone, luteinizing hormone, epidermal growth factor, insulin-like growth factor I, and transforming growth factor beta1. (1/1318)

Modulation of glucose metabolic capacity of human preantral follicles in vitro by gonadotropins and intraovarian growth factors was evaluated by monitoring the activities of phosphofructokinase (PFK) and pyruvate kinase (PK), two regulatory enzymes of the glycolytic pathway, and malate dehydrogenase (MDH), a key mitochondrial enzyme of the Krebs cycle. Preantral follicles in classes 1 and 2 from premenopausal women were cultured separately in vitro in the absence or presence of FSH, LH, epidermal growth factor (EGF), insulin-like growth factor (IGF-I), or transforming growth factor beta1 (TGFbeta1) for 24 h. Mitochondrial fraction was separated from the cytosolic fraction, and both fractions were used for enzyme assays. FSH and LH significantly stimulated PFK and PK activities in class 1 and 2 follicles; however, a 170-fold increase in MDH activity was noted for class 2 follicles that were exposed to FSH. Although both EGF and TGFbeta1 stimulated glycolytic and Krebs cycle enzymes for class 1 preantral follicles, TGFbeta1 consistently stimulated the activities of both glycolytic enzymes more than that of EGF. IGF-I induced PK and MDH activities in class 1 follicles but negatively influenced PFK activity for class 1 follicles. In general, only gonadotropins consistently stimulated both glycolytic and Krebs cycle enzyme activities several-fold in class 2 follicles. These results suggest that gonadotropins and ovarian growth factors differentially influence follicular energy-producing capacity from glucose. Moreover, gonadotropins may either directly influence glucose metabolism in class 2 preantral follicles or do so indirectly through factors other than the well-known intraovarian growth factors. Because growth factors modulate granulosa cell mitosis and functionality, their role on energy production may be related to specific cellular activities.  (+info)

Activities of citrate synthase, NAD+-linked and NADP+-linked isocitrate dehydrogenases, glutamate dehydrogenase, aspartate aminotransferase and alanine aminotransferase in nervous tissues from vertebrates and invertebrates. (2/1318)

1. The activities of citrate synthase and NAD+-linked and NADP+-linked isocitrate dehydrogenases were measured in nervous tissue from different animals in an attempt to provide more information about the citric acid cycle in this tissue. In higher animals the activities of citrate synthase are greater than the sum of activities of the isocitrate dehydrogenases, whereas they are similar in nervous tissues from the lower animals. This suggests that in higher animals the isocitrate dehydrogenase reaction is far-removed from equilibrium. If it is assumed that isocitrate dehydrogenase activities provide an indication of the maximum flux through the citric acid cycle, the maximum glycolytic capacity in nervous tissue is considerably greater than that of the cycle. This suggest that glycolysis can provide energy in excess of the aerobic capacity of the tissue. 2. The activities of glutamate dehydrogenase are high in most nervous tissues and the activities of aspartate aminotransferase are high in all nervous tissue investigated. However, the activities of alanine aminotransferase are low in all tissues except the ganglia of the waterbug and cockroach. In these insect tissues, anaerobic glycolysis may result in the formation of alanine rather than lactate.  (+info)

The importance of pyruvate availability to PDC activation and anaplerosis in human skeletal muscle. (3/1318)

No studies have singularly investigated the relationship between pyruvate availability, pyruvate dehydrogenase complex (PDC) activation, and anaplerosis in skeletal muscle. This is surprising given the functional importance attributed to these processes in normal and disease states. We investigated the effects of changing pyruvate availability with dichloroacetate (DCA), epinephrine, and pyruvate infusions on PDC activation and accumulation of acetyl groups and tricarboxylic acid (TCA) cycle intermediates (TCAI) in human muscle. DCA increased resting PDC activity sixfold (P < 0.05) but decreased the muscle TCAI pool (mmol/kg dry muscle) from 1.174 +/- 0.042 to 0.747 +/- 0.055 (P < 0.05). This was probably a result of pyruvate being diverted to acetyl-CoA and acetylcarnitine after near-maximal activation of PDC by DCA. Conversely, neither epinephrine nor pyruvate activated PDC. However, both increased the TCAI pool (1.128 +/- 0.076 to 1.614 +/- 0.188, P < 0.05 and 1.098 +/- 0.059 to 1.385 +/- 0.114, P < 0.05, respectively) by providing a readily available pool of pyruvate for anaplerosis. These data support the hypothesis that TCAI pool expansion is principally a reflection of increased muscle pyruvate availability and, together with our previous work (J. A. Timmons, S. M. Poucher, D. Constantin-Teodosiu, V. Worrall, I. A. Macdonald, and P. L. Greenhaff. J. Clin. Invest. 97: 879-883, 1996), indicate that TCA cycle expansion may be of little functional significance to TCA cycle flux. It would appear therefore that the primary effect of DCA on oxidative ATP provision is to provide a readily available pool of acetyl groups to the TCA cycle at the onset of exercise rather than increasing TCA cycle flux by expanding the TCAI pool.  (+info)

Low oxygen inhibits but complex high-glucose medium facilitates in vitro maturation of squirrel monkey oocyte-granulosa cell complexes. (4/1318)

PURPOSE: The objectives of these in vitro maturation studies in primate cumulus-oocyte complexes (COCs) were to evaluate the effect of a reduced-oxygen environment and to compare medium with a high-glucose concentration to medium with pyruvate but no glucose. METHODS: COCs were retrieved from squirrel monkeys stimulated with 1 mg of follicle-stimulating hormone (FSH) for 4-6 days. Experiment 1 examined maturation after 48 hr in 5% O2/5% CO2/90% N2 compared with 5% CO2/air. The medium was CMRL-1066 containing moderate glucose (5.5 mM) supplemented with 1 mM glutamine, 0.33 mM pyruvate, 0.075 IU/ml human FSH, 5 IU/ml human chorionic gonadotropin, 75 U penicillin G/ml, and 20% fetal bovine serum. Experiment 2 in 5% CO2/air, compared P-1 medium (pyruvate and lactate but no glucose) to Waymouth's medium (27.5 mM glucose), both with identical supplements. RESULTS: Only 3 (8%) of 37 COCs matured in 5% O2, while 39 (49%) of 80 matured in ambient O2. Fourteen (22%) of 64 complexes matured in P-1 medium, compared to 47 (49%) of 96 meiosis II oocytes in Waymouth's medium (P < 0.05). CONCLUSIONS: These are the first primate studies showing detrimental effects of reduced-oxygen culture on in vitro maturation. Additionally, maturation was enhanced with complex high-glucose medium suggesting that the predominant metabolism is aerobic glycolysis.  (+info)

A minimal mechanism for bacterial pattern formation. (5/1318)

Colonies of Escherichia coli or Salmonella typhimurium form geometrically complex patterns when exposed to, or feeding on, intermediates of the tricarboxylic acid (TCA) cycle. In response to the TCA cycle intermediate, the bacteria secrete aspartate, a potent chemo-attractant. As a result, the cells form high-density aggregates arranged in striking regular patterns. The simplest are temporary spots formed in a liquid medium by both E. coli and S. typhimurium. In semi-solid medium S. typhimurium forms concentric rings arising from a low-density bacterial lawn, which are either continuous or spotted, whereas E. coli forms complex patterns arising from a dense swarm ring, including interdigitated spots (also called sunflower spirals), radial spots, radial stripes and chevrons. We present a mathematical model that captures all three of the pattern-forming processes experimentally observed in both E. coli and S. typhimurium, using a minimum of assumptions.  (+info)

The tricarboxylic acid cycle of Helicobacter pylori. (6/1318)

The composition and properties of the tricarboxylic acid cycle of the microaerophilic human pathogen Helicobacter pylori were investigated in situ and in cell extracts using [1H]- and [13C]-NMR spectroscopy and spectrophotometry. NMR spectroscopy assays enabled highly specific measurements of some enzyme activities, previously not possible using spectrophotometry, in in situ studies with H. pylori, thus providing the first accurate picture of the complete tricarboxylic acid cycle of the bacterium. The presence, cellular location and kinetic parameters of citrate synthase, aconitase, isocitrate dehydrogenase, alpha-ketoglutarate oxidase, fumarate reductase, fumarase, malate dehydrogenase, and malate synthase activities in H. pylori are described. The absence of other enzyme activities of the cycle, including alpha-ketoglutarate dehydrogenase, succinyl-CoA synthetase, and succinate dehydrogenase also are shown. The H. pylori tricarboxylic acid cycle appears to be a noncyclic, branched pathway, characteristic of anaerobic metabolism, directed towards the production of succinate in the reductive dicarboxylic acid branch and alpha-ketoglutarate in the oxidative tricarboxylic acid branch. Both branches were metabolically linked by the presence of alpha-ketoglutarate oxidase activity. Under the growth conditions employed, H. pylori did not possess an operational glyoxylate bypass, owing to the absence of isocitrate lyase activity; nor a gamma-aminobutyrate shunt, owing to the absence of both gamma-aminobutyrate transaminase and succinic semialdehyde dehydrogenase activities. The catalytic and regulatory properties of the H. pylori tricarboxylic acid cycle enzymes are discussed by comparing their amino acid sequences with those of other, more extensively studied enzymes.  (+info)

Replenishment and depletion of citric acid cycle intermediates in skeletal muscle. Indication of pyruvate carboxylation. (7/1318)

The effects of various substrates on the concentrations of free amino acids, citric acid cycle intermediates and acylcarnitines were studies in perfused hindquarter of rat in presence of glucose and insulin in order to assess regulatory mechanisms of the level of citric acid cycle intermediates in skeletal muscle. 1. Acetate and acetoacetate effected a significant increase in the level of citrate cycle intermediates and accumulation of acetylcarnitine. These changes were accompanied by a reduction in the level of alanine. The concentration of AMP was significantly elevated. 2. Muscle mitochondria fixed 14CO2 in the presence of pyruvate. The products were identified as malate or citrate when whole and disintegrated mitochondria were used respectively. The fixation was greatly stimulated by acetylcarnitine. 3. Acetylcarnitine inhibited the production of pyruvate from malate by muscle mitochondria. 4. Perfusion with 2-oxoisocaproate and 2-oxoisovalerate promoted increases in the level of citric cycle intermediates, a drop in both alanine and glutamate, and accumulation of branched-chain acylcarnitines. 2-Oxoisocaproate also caused a reduction of alanine released from the muscle. 5. Perfusion with leucine and valine did not change the concentration of citric acid cycle intermediates, but elevated glutamate and still more the concentration of alanine. 6. It is concluded that citric cycle intermediate level in the perfused resting muscle is modified by a) conditions which change the concentration of acetyl-CoA and thereby modify the rate of pyruvate carboxylation and decarboxylation of malate via malic enzyme b) conditions which change the concentration of pyruvate cause changes in alanine and cycle intermediates in the same direction via transamination reactions c) conditions which change the concentrations of 2-oxoacids which are converted to cycle intermediates via oxidation.  (+info)

Microbial oxidation of methane and methanol: isolation of methane-utilizing bacteria and characterization of a facultative methane-utilizing isolate. (8/1318)

A methane-utilizing organism capable of growth both on methane and on more complex organic substrates as a sole source of carbon and energy, has been isolated and studied in detail. Suspensions of methane-grown cells of this organism oxidized C-1 compounds (methane, methanol, formaldehyde, formate); hydrocarbons (ethane, propane); primary alcohols (ethanol, propanol); primary aldehydes (acetaldehyde, propionaldehyde); alkenes (ethylene, propylene); dimethylether; and organic acids (acetate, malate, succinate, isocitrate). Suspensions of methanol-or succinate-grown cells did not oxidize methane, ethane, propane, ethylene, propylene, or dimethylether, suggesting that the enzymatic systems required for oxidation of these substrates are induced only during growth on methane. Extracts of methane-grown cells contained a particulate reduced nicotinamide adenine dinucleotide-dependent methane monooxygenase activity. Oxidation of methanol, formaldehyde, and primary alcohols was catalyzed by a phenazine methosulfate-linked, ammonium ion-requiring methanol dehydrogenase. Oxidation of primary aldehydes was catalyzed by a phenazine methosulfate-linked, ammonium ion-independent aldehyde dehydrogenase. Formate was oxidized by a nicotinamide adenine dinucleotide-specific formate dehydrogenase. Extracts of methane-grown, but not succinate-grown, cells contained the key enzymes of the serine pathway, hydroxypyruvate reductase and malate lyase, indicating that the enzymes of C-1 assimilation are induced only during growth on C-1 compounds. Glucose-6-phosphate dehydrogenase was induced during growth on glucose. Extracts of methane-grown cells contained low levels of enzymes of the tricarboxylic acid cycle, including alpha-keto glutarate dehydrogenase, relative to the levels found during growth on succinate.  (+info)

The Citric Acid Cycle, also known as the Krebs cycle or tricarboxylic acid (TCA) cycle, is a crucial metabolic pathway in the cell's powerhouse, the mitochondria. It plays a central role in the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins, into carbon dioxide and high-energy electrons. This process generates energy in the form of ATP (adenosine triphosphate), reducing equivalents (NADH and FADH2), and water.

The cycle begins with the condensation of acetyl-CoA with oxaloacetate, forming citrate. Through a series of enzyme-catalyzed reactions, citrate is converted back to oxaloacetate, releasing two molecules of carbon dioxide, one GTP (guanosine triphosphate), three NADH, one FADH2, and regenerating oxaloacetate to continue the cycle. The reduced coenzymes (NADH and FADH2) then donate their electrons to the electron transport chain, driving ATP synthesis through chemiosmosis. Overall, the Citric Acid Cycle is a vital part of cellular respiration, connecting various catabolic pathways and generating energy for the cell's metabolic needs.

Citric acid is a weak organic acid that is widely found in nature, particularly in citrus fruits such as lemons and oranges. Its chemical formula is C6H8O7, and it exists in a form known as a tribasic acid, which means it can donate three protons in chemical reactions.

In the context of medical definitions, citric acid may be mentioned in relation to various physiological processes, such as its role in the Krebs cycle (also known as the citric acid cycle), which is a key metabolic pathway involved in energy production within cells. Additionally, citric acid may be used in certain medical treatments or therapies, such as in the form of citrate salts to help prevent the formation of kidney stones. It may also be used as a flavoring agent or preservative in various pharmaceutical preparations.

Citrates are the salts or esters of citric acid, a weak organic acid that is naturally found in many fruits and vegetables. In a medical context, citrates are often used as a buffering agent in intravenous fluids to help maintain the pH balance of blood and other bodily fluids. They are also used in various medical tests and treatments, such as in urine alkalinization and as an anticoagulant in kidney dialysis solutions. Additionally, citrate is a component of some dietary supplements and medications.

I'm sorry for any confusion, but "Malates" is not a recognized term in medical terminology. It's possible there may be a spelling mistake or it could be a slang term or an abbreviation that is not widely recognized. If you have more context or information, I'd be happy to try and help further.

Isocitrate Dehydrogenase (IDH) is an enzyme that catalyzes the oxidative decarboxylation of isocitrate to α-ketoglutarate in the presence of NAD+ or NADP+, producing NADH or NADPH respectively. This reaction occurs in the citric acid cycle, also known as the Krebs cycle or tricarboxylic acid (TCA) cycle, which is a crucial metabolic pathway in the cell's energy production and biosynthesis of various molecules. There are three isoforms of IDH found in humans: IDH1 located in the cytosol, IDH2 in the mitochondrial matrix, and IDH3 within the mitochondria. Mutations in IDH1 and IDH2 have been associated with several types of cancer, such as gliomas and acute myeloid leukemia (AML), leading to abnormal accumulation of 2-hydroxyglutarate, which can contribute to tumorigenesis.

Oxaloacetates are organic compounds that are integral to the Krebs cycle, also known as the citric acid cycle, in biological energy production. Specifically, oxaloacetate is an important intermediate compound within this metabolic pathway, found in the mitochondria of cells.

In the context of a medical definition, oxaloacetates are not typically referred to directly. Instead, the term "oxaloacetic acid" might be used, which is the conjugate acid of the oxaloacetate ion. Oxaloacetic acid has the chemical formula C4H4O5 and appears in various biochemical reactions as a crucial component of cellular respiration.

The Krebs cycle involves several stages where oxaloacetic acid plays a significant role:

1. In the first step, oxaloacetic acid combines with an acetyl group (derived from acetyl-CoA) to form citric acid, releasing coenzyme A in the process. This reaction is catalyzed by citrate synthase.
2. Throughout subsequent steps of the cycle, citric acid undergoes a series of reactions that generate energy in the form of NADH and FADH2 (reduced forms of nicotinamide adenine dinucleotide and flavin adenine dinucleotide, respectively), as well as GTP (guanosine triphosphate).
3. At the end of the cycle, oxaloacetic acid is regenerated to continue the process anew. This allows for continuous energy production within cells.

In summary, while "oxaloacetates" isn't a standard term in medical definitions, it does refer to an essential component (oxaloacetic acid) of the Krebs cycle that plays a critical role in cellular respiration and energy production.

Fumarate hydratase (FH) is an enzyme that plays a crucial role in the citric acid cycle, also known as the Krebs cycle or tricarboxylic acid (TCA) cycle. The citric acid cycle is a series of chemical reactions used by all living cells to generate energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins into adenosine triphosphate (ATP), carbon dioxide, and water.

Fumarate hydratase is specifically responsible for catalyzing the conversion of fumarate to malate in this cycle. A deficiency or dysfunction of this enzyme can lead to various metabolic disorders and hereditary diseases, such as fumarate hydratase deficiency, which may manifest as neurological issues, hemolytic anemia, and an increased risk of developing renal cell carcinoma.

Aconitate hydratase is an enzyme that catalyzes the reversible conversion of citrate to isocitrate in the Krebs cycle (also known as the tricarboxylic acid cycle or TCA cycle), which is a central metabolic pathway in the cell. This enzyme is also called aconitase or aconitate dehydratase.

The reaction catalyzed by aconitate hydratase involves two steps: first, the removal of a water molecule from citrate to form cis-aconitate; and second, the addition of a water molecule to cis-aconitate to form isocitrate. The enzyme binds to the substrate in such a way that it stabilizes the transition state between citrate and cis-aconitate, making the reaction more favorable.

Aconitate hydratase plays an important role in energy metabolism, as it helps generate NADH and FADH2, which are used to produce ATP through oxidative phosphorylation. Additionally, aconitate hydratase has been implicated in various diseases, including neurodegenerative disorders, cancer, and bacterial infections.

Alpha-ketoglutaric acid, also known as 2-oxoglutarate, is not an acid in the traditional sense but is instead a key molecule in the Krebs cycle (citric acid cycle), which is a central metabolic pathway involved in cellular respiration. Alpha-ketoglutaric acid is a crucial intermediate in the process of converting carbohydrates, fats, and proteins into energy through oxidation. It plays a vital role in amino acid synthesis and the breakdown of certain amino acids. Additionally, it serves as an essential cofactor for various enzymes involved in numerous biochemical reactions within the body. Any medical conditions or disorders related to alpha-ketoglutaric acid would typically be linked to metabolic dysfunctions or genetic defects affecting the Krebs cycle.

Pyruvic acid, also known as 2-oxopropanoic acid, is a key metabolic intermediate in both anaerobic and aerobic respiration. It is a carboxylic acid with a ketone functional group, making it a β-ketoacid. In the cytosol, pyruvate is produced from glucose during glycolysis, where it serves as a crucial link between the anaerobic breakdown of glucose and the aerobic process of cellular respiration in the mitochondria.

During low oxygen availability or high energy demands, pyruvate can be converted into lactate through anaerobic glycolysis, allowing for the continued production of ATP (adenosine triphosphate) without oxygen. In the presence of adequate oxygen and functional mitochondria, pyruvate is transported into the mitochondrial matrix where it undergoes oxidative decarboxylation to form acetyl-CoA by the enzyme pyruvate dehydrogenase complex (PDC). This reaction also involves the reduction of NAD+ to NADH and the release of CO2. Acetyl-CoA then enters the citric acid cycle, where it is further oxidized to produce energy in the form of ATP, NADH, FADH2, and GTP (guanosine triphosphate) through a series of enzymatic reactions.

In summary, pyruvic acid is a vital metabolic intermediate that plays a significant role in energy production pathways, connecting glycolysis to both anaerobic and aerobic respiration.

The Ketoglutarate Dehydrogenase Complex (KGDC or α-KGDH) is a multi-enzyme complex that plays a crucial role in the Krebs cycle, also known as the citric acid cycle. It is located within the mitochondrial matrix of eukaryotic cells and functions to catalyze the oxidative decarboxylation of α-ketoglutarate into succinyl-CoA, thereby connecting the Krebs cycle to the electron transport chain for energy production.

The KGDC is composed of three distinct enzymes:

1. α-Ketoglutarate dehydrogenase (E1): This enzyme catalyzes the decarboxylation and oxidation of α-ketoglutarate to form a thioester intermediate with lipoamide, which is bound to the E2 component.
2. Dihydrolipoyl succinyltransferase (E2): This enzyme facilitates the transfer of the acetyl group from the lipoamide cofactor to CoA, forming succinyl-CoA and regenerating oxidized lipoamide.
3. Dihydrolipoyl dehydrogenase (E3): The final enzyme in the complex catalyzes the reoxidation of reduced lipoamide back to its disulfide form, using FAD as a cofactor and transferring electrons to NAD+, forming NADH.

The KGDC is subject to regulation by several mechanisms, including phosphorylation-dephosphorylation reactions that can inhibit or activate the complex, respectively. Dysfunction of this enzyme complex has been implicated in various diseases, such as neurodegenerative disorders and cancer.

Oxaloacetic acid is a chemical compound that plays a significant role in the Krebs cycle, also known as the citric acid cycle. It is a key metabolic intermediate in both glucose and fatty acid catabolism. Oxaloacetic acid is a four-carbon carboxylic acid that has two carboxyl groups and one ketone group.

In the Krebs cycle, oxaloacetic acid reacts with acetyl-CoA (an activated form of acetic acid) to form citric acid, releasing CoA and initiating the cycle. Throughout the cycle, oxaloacetic acid is continuously regenerated from malate, another intermediate in the cycle.

Additionally, oxaloacetic acid plays a role in amino acid metabolism as it can accept an amino group (NH3) to form aspartic acid, which is an essential component of several biochemical processes, including protein synthesis and the urea cycle.

Malate Dehydrogenase (MDH) is an enzyme that plays a crucial role in the Krebs cycle, also known as the citric acid cycle or tricarboxylic acid (TCA) cycle. It catalyzes the reversible oxidation of malate to oxaloacetate, while simultaneously reducing NAD+ to NADH. This reaction is essential for energy production in the form of ATP and NADH within the cell.

There are two main types of Malate Dehydrogenase:

1. NAD-dependent Malate Dehydrogenase (MDH1): Found primarily in the cytoplasm, this isoform plays a role in the malate-aspartate shuttle, which helps transfer reducing equivalents between the cytoplasm and mitochondria.
2. FAD-dependent Malate Dehydrogenase (MDH2): Located within the mitochondrial matrix, this isoform is involved in the Krebs cycle for energy production.

Abnormal levels of Malate Dehydrogenase enzyme can be indicative of certain medical conditions or diseases, such as myocardial infarction (heart attack), muscle damage, or various types of cancer. Therefore, MDH enzyme activity is often assessed in diagnostic tests to help identify and monitor these health issues.

Acetyl Coenzyme A, often abbreviated as Acetyl-CoA, is a key molecule in metabolism, particularly in the breakdown and oxidation of carbohydrates, fats, and proteins to produce energy. It is a coenzyme that plays a central role in the cellular process of transforming the energy stored in the chemical bonds of nutrients into a form that the cell can use.

Acetyl-CoA consists of an acetyl group (two carbon atoms) linked to coenzyme A, a complex organic molecule. This linkage is facilitated by an enzyme called acetyltransferase. Once formed, Acetyl-CoA can enter various metabolic pathways. In the citric acid cycle (also known as the Krebs cycle), Acetyl-CoA is further oxidized to release energy in the form of ATP, NADH, and FADH2, which are used in other cellular processes. Additionally, Acetyl-CoA is involved in the biosynthesis of fatty acids, cholesterol, and certain amino acids.

In summary, Acetyl Coenzyme A is a vital molecule in metabolism that connects various biochemical pathways for energy production and biosynthesis.

Succinic acid, also known as butanedioic acid, is an organic compound with the chemical formula HOOC(CH2)2COOH. It is a white crystalline powder that is soluble in water and has a slightly acerbic taste. In medicine, succinic acid is not used as a treatment for any specific condition. However, it is a naturally occurring substance found in the body and plays a role in the citric acid cycle, which is a key process in energy production within cells. It can also be found in some foods and is used in the manufacturing of various products such as pharmaceuticals, resins, and perfumes.

Carbon isotopes are variants of the chemical element carbon that have different numbers of neutrons in their atomic nuclei. The most common and stable isotope of carbon is carbon-12 (^{12}C), which contains six protons and six neutrons. However, carbon can also come in other forms, known as isotopes, which contain different numbers of neutrons.

Carbon-13 (^{13}C) is a stable isotope of carbon that contains seven neutrons in its nucleus. It makes up about 1.1% of all carbon found on Earth and is used in various scientific applications, such as in tracing the metabolic pathways of organisms or in studying the age of fossilized materials.

Carbon-14 (^{14}C), also known as radiocarbon, is a radioactive isotope of carbon that contains eight neutrons in its nucleus. It is produced naturally in the atmosphere through the interaction of cosmic rays with nitrogen gas. Carbon-14 has a half-life of about 5,730 years, which makes it useful for dating organic materials, such as archaeological artifacts or fossils, up to around 60,000 years old.

Carbon isotopes are important in many scientific fields, including geology, biology, and medicine, and are used in a variety of applications, from studying the Earth's climate history to diagnosing medical conditions.

Pyruvate is a negatively charged ion or group of atoms, called anion, with the chemical formula C3H3O3-. It is formed from the decomposition of glucose and other sugars in the process of cellular respiration. Pyruvate plays a crucial role in the metabolic pathways that generate energy for cells.

In the cytoplasm, pyruvate is produced through glycolysis, where one molecule of glucose is broken down into two molecules of pyruvate, releasing energy and producing ATP (adenosine triphosphate) and NADH (reduced nicotinamide adenine dinucleotide).

In the mitochondria, pyruvate can be further metabolized through the citric acid cycle (also known as the Krebs cycle) to produce more ATP. The process involves the conversion of pyruvate into acetyl-CoA, which then enters the citric acid cycle and undergoes a series of reactions that generate energy in the form of ATP, NADH, and FADH2 (reduced flavin adenine dinucleotide).

Overall, pyruvate is an important intermediate in cellular respiration and plays a central role in the production of energy for cells.

Succinate dehydrogenase (SDH) is an enzyme complex that plays a crucial role in the process of cellular respiration, specifically in the citric acid cycle (also known as the Krebs cycle) and the electron transport chain. It is located in the inner mitochondrial membrane of eukaryotic cells.

SDH catalyzes the oxidation of succinate to fumarate, converting it into a molecule of fadaquate in the process. During this reaction, two electrons are transferred from succinate to the FAD cofactor within the SDH enzyme complex, reducing it to FADH2. These electrons are then passed on to ubiquinone (CoQ), which is a mobile electron carrier in the electron transport chain, leading to the generation of ATP, the main energy currency of the cell.

SDH is also known as mitochondrial complex II because it is the second complex in the electron transport chain. Mutations in the genes encoding SDH subunits or associated proteins have been linked to various human diseases, including hereditary paragangliomas, pheochromocytomas, gastrointestinal stromal tumors (GISTs), and some forms of neurodegenerative disorders.

Acetates, in a medical context, most commonly refer to compounds that contain the acetate group, which is an functional group consisting of a carbon atom bonded to two hydrogen atoms and an oxygen atom (-COO-). An example of an acetate is sodium acetate (CH3COONa), which is a salt formed from acetic acid (CH3COOH) and is often used as a buffering agent in medical solutions.

Acetates can also refer to a group of medications that contain acetate as an active ingredient, such as magnesium acetate, which is used as a laxative, or calcium acetate, which is used to treat high levels of phosphate in the blood.

In addition, acetates can also refer to a process called acetylation, which is the addition of an acetyl group (-COCH3) to a molecule. This process can be important in the metabolism and regulation of various substances within the body.

Glyoxylates are organic compounds that are intermediates in various metabolic pathways, including the glyoxylate cycle. The glyoxylate cycle is a modified version of the Krebs cycle (also known as the citric acid cycle) and is found in plants, bacteria, and some fungi.

Glyoxylates are formed from the breakdown of certain amino acids or from the oxidation of one-carbon units. They can be converted into glycine, an important amino acid involved in various metabolic processes. In the glyoxylate cycle, glyoxylates are combined with acetyl-CoA to form malate and succinate, which can then be used to synthesize glucose or other organic compounds.

Abnormal accumulation of glyoxylates in the body can lead to the formation of calcium oxalate crystals, which can cause kidney stones and other health problems. Certain genetic disorders, such as primary hyperoxaluria, can result in overproduction of glyoxylates and increased risk of kidney stone formation.

According to the US National Library of Medicine's Medical Subject Headings (MeSH), Succinate-CoA Ligases are defined as:

Enzymes that catalyze the conversion of succinyl-CoA and diphosphate into CoA, carbon dioxide, and a high-energy phosphate bond in an ATP or a GTP molecule. They are classified into two types according to the type of high-energy phosphate bond they form: adenosine triphosphatases (succinate-coa ligase (adenosine triphosphate)) or guanosine triphosphatases (succinate-coa ligase (guanosine triphosphate)).

Source: National Library of Medicine. (2021). Succinate-CoA Ligases. In: MeSH Database. Bethesda, MD: National Library of Medicine. Available at:

Fluoroacetates are organic compounds that contain a fluorine atom and an acetic acid group. The most well-known and notorious compound in this family is sodium fluoroacetate, also known as 1080 or compound 1080, which is a potent metabolic poison. It works by interfering with the citric acid cycle, a critical process that generates energy in cells. Specifically, fluoroacetates are converted into fluorocitrate, which inhibits an enzyme called aconitase, leading to disruption of cellular metabolism and ultimately cell death.

Fluoroacetates have been used as rodenticides and pesticides, but their use is highly regulated due to their high toxicity to non-target species, including humans. Exposure to fluoroacetates can cause a range of symptoms, including nausea, vomiting, seizures, and cardiac arrest, and can be fatal if not treated promptly.

The cell cycle is a series of events that take place in a cell leading to its division and duplication. It consists of four main phases: G1 phase, S phase, G2 phase, and M phase.

During the G1 phase, the cell grows in size and synthesizes mRNA and proteins in preparation for DNA replication. In the S phase, the cell's DNA is copied, resulting in two complete sets of chromosomes. During the G2 phase, the cell continues to grow and produces more proteins and organelles necessary for cell division.

The M phase is the final stage of the cell cycle and consists of mitosis (nuclear division) and cytokinesis (cytoplasmic division). Mitosis results in two genetically identical daughter nuclei, while cytokinesis divides the cytoplasm and creates two separate daughter cells.

The cell cycle is regulated by various checkpoints that ensure the proper completion of each phase before progressing to the next. These checkpoints help prevent errors in DNA replication and division, which can lead to mutations and cancer.

Fumarates are the salts or esters of fumaric acid, a naturally occurring organic compound with the formula HO2C-CH=CH-CO2H. In the context of medical therapy, fumarates are used as medications for the treatment of psoriasis and multiple sclerosis.

One such medication is dimethyl fumarate (DMF), which is a stable salt of fumaric acid. DMF has anti-inflammatory and immunomodulatory properties, and it's used to treat relapsing forms of multiple sclerosis (MS) and moderate-to-severe plaque psoriasis.

The exact mechanism of action of fumarates in these conditions is not fully understood, but they are thought to modulate the immune system and have antioxidant effects. Common side effects of fumarate therapy include gastrointestinal symptoms such as diarrhea, nausea, and abdominal pain, as well as flushing and skin reactions.

Succinates, in a medical context, most commonly refer to the salts or esters of succinic acid. Succinic acid is a dicarboxylic acid that is involved in the Krebs cycle, which is a key metabolic pathway in cells that generates energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins.

Succinates can also be used as a buffer in medical solutions and as a pharmaceutical intermediate in the synthesis of various drugs. In some cases, succinate may be used as a nutritional supplement or as a component of parenteral nutrition formulations to provide energy and help maintain acid-base balance in patients who are unable to eat normally.

It's worth noting that there is also a condition called "succinic semialdehyde dehydrogenase deficiency" which is a genetic disorder that affects the metabolism of the amino acid gamma-aminobutyric acid (GABA). This condition can lead to an accumulation of succinic semialdehyde and other metabolic byproducts, which can cause neurological symptoms such as developmental delay, hypotonia, and seizures.

Glycolysis is a fundamental metabolic pathway that occurs in the cytoplasm of cells, consisting of a series of biochemical reactions. It's the process by which a six-carbon glucose molecule is broken down into two three-carbon pyruvate molecules. This process generates a net gain of two ATP molecules (the main energy currency in cells), two NADH molecules, and two water molecules.

Glycolysis can be divided into two stages: the preparatory phase (or 'energy investment' phase) and the payoff phase (or 'energy generation' phase). During the preparatory phase, glucose is phosphorylated twice to form glucose-6-phosphate and then converted to fructose-1,6-bisphosphate. These reactions consume two ATP molecules but set up the subsequent breakdown of fructose-1,6-bisphosphate into triose phosphates in the payoff phase. In this second stage, each triose phosphate is further oxidized and degraded to produce one pyruvate molecule, one NADH molecule, and one ATP molecule through substrate-level phosphorylation.

Glycolysis does not require oxygen to proceed; thus, it can occur under both aerobic (with oxygen) and anaerobic (without oxygen) conditions. In the absence of oxygen, the pyruvate produced during glycolysis is further metabolized through fermentation pathways such as lactic acid fermentation or alcohol fermentation to regenerate NAD+, which is necessary for glycolysis to continue.

In summary, glycolysis is a crucial process in cellular energy metabolism, allowing cells to convert glucose into ATP and other essential molecules while also serving as a starting point for various other biochemical pathways.

Glutamates are the salt or ester forms of glutamic acid, which is a naturally occurring amino acid and the most abundant excitatory neurotransmitter in the central nervous system. Glutamate plays a crucial role in various brain functions, such as learning, memory, and cognition. However, excessive levels of glutamate can lead to neuronal damage or death, contributing to several neurological disorders, including stroke, epilepsy, and neurodegenerative diseases like Alzheimer's and Parkinson's.

Glutamates are also commonly found in food as a natural flavor enhancer, often listed under the name monosodium glutamate (MSG). While MSG has been extensively studied, its safety remains a topic of debate, with some individuals reporting adverse reactions after consuming foods containing this additive.

Gluconeogenesis is a metabolic pathway that occurs in the liver, kidneys, and to a lesser extent in the small intestine. It involves the synthesis of glucose from non-carbohydrate precursors such as lactate, pyruvate, glycerol, and certain amino acids. This process becomes particularly important during periods of fasting or starvation when glucose levels in the body begin to drop, and there is limited carbohydrate intake to replenish them.

Gluconeogenesis helps maintain blood glucose homeostasis by providing an alternative source of glucose for use by various tissues, especially the brain, which relies heavily on glucose as its primary energy source. It is a complex process that involves several enzymatic steps, many of which are regulated to ensure an adequate supply of glucose while preventing excessive production, which could lead to hyperglycemia.

Ketone bodies, also known as ketones or ketoacids, are organic compounds that are produced by the liver during the metabolism of fats when carbohydrate intake is low. They include acetoacetate (AcAc), beta-hydroxybutyrate (BHB), and acetone. These molecules serve as an alternative energy source for the body, particularly for the brain and heart, when glucose levels are insufficient to meet energy demands.

In a healthy individual, ketone bodies are present in low concentrations; however, during periods of fasting, starvation, or intense physical exertion, ketone production increases significantly. In some pathological conditions like uncontrolled diabetes mellitus, the body may produce excessive amounts of ketones, leading to a dangerous metabolic state called diabetic ketoacidosis (DKA).

Elevated levels of ketone bodies can be detected in blood or urine and are often used as an indicator of metabolic status. Monitoring ketone levels is essential for managing certain medical conditions, such as diabetes, where maintaining optimal ketone concentrations is crucial to prevent complications.

Heptanoates are chemical compounds that contain the functional group of heptanoic acid. Heptanoic acid, also known as n-caproic acid, is a type of carboxylic acid with a 7-carbon chain and the molecular formula C7H15COOH.

Heptanoates are commonly used in the production of various chemicals, including flavors, fragrances, and pharmaceuticals. In medicine, heptanoates may be used as esters in the formulation of drugs to improve their solubility, absorption, and stability. For example, some injectable forms of medications may use heptanoate salts or esters to enhance their delivery into the body.

It's important to note that specific medical definitions for "heptanoates" may vary depending on the context and application.

Malate Synthase is a key enzyme in the gluconeogenesis pathway and the glyoxylate cycle, which are present in many organisms including plants, bacteria, and parasites. The glyoxylate cycle is a variation of the citric acid cycle (Krebs cycle) that allows these organisms to convert two-carbon molecules into four-carbon molecules, bypassing steps that require oxygen.

Malate Synthase catalyzes the reaction between glyoxylate and acetyl-CoA to produce malate, a four-carbon compound. This enzyme plays a crucial role in enabling these organisms to utilize fatty acids as a carbon source for growth and energy production, particularly under conditions where oxygen is limited or absent. In humans, Malate Synthase is not typically found, but its presence can indicate certain parasitic infections or metabolic disorders.

Pyruvate carboxylase is a biotin-containing enzyme that plays a crucial role in gluconeogenesis, the process of generating new glucose molecules from non-carbohydrate sources. The enzyme catalyzes the conversion of pyruvate to oxaloacetate, an important intermediate in several metabolic pathways, particularly in the liver, kidneys, and brain.

The reaction catalyzed by pyruvate carboxylase is as follows:

Pyruvate + CO2 + ATP + H2O → Oxaloacetate + ADP + Pi + 2H+

In this reaction, pyruvate reacts with bicarbonate (HCO3-) to form oxaloacetate, consuming one molecule of ATP in the process. The generation of oxaloacetate provides a key entry point for non-carbohydrate precursors, such as lactate and certain amino acids, to enter the gluconeogenic pathway.

Pyruvate carboxylase deficiency is a rare but severe genetic disorder that can lead to neurological impairment and developmental delays due to the disruption of energy metabolism in the brain.

Dicarboxylic acid transporters are a type of membrane transport protein that are responsible for the transportation of dicarboxylic acids across biological membranes. Dicarboxylic acids are organic compounds that contain two carboxyl groups, and they play important roles in various metabolic processes within the body.

The sodium-dependent dicarboxylic acid transporters (NaDCs) are a subfamily of these transporters that are widely expressed in many tissues, including the kidney, intestine, and brain. NaDCs mediate the uptake of dicarboxylates, such as succinate and glutarate, into cells in an energy-dependent manner, using the gradient of sodium ions across the membrane to drive the transport process.

The other subfamily of dicarboxylic acid transporters are the proton-coupled dicarboxylate transporters (PCDTs), which use a proton gradient to transport dicarboxylates. These transporters play important roles in the absorption and metabolism of dietary fibers, as well as in the regulation of intracellular pH.

Defects in dicarboxylic acid transporters have been implicated in several human diseases, including renal tubular acidosis, a condition characterized by impaired ability to excrete hydrogen ions and reabsorb bicarbonate ions in the kidney.

Glucose is a simple monosaccharide (or single sugar) that serves as the primary source of energy for living organisms. It's a fundamental molecule in biology, often referred to as "dextrose" or "grape sugar." Glucose has the molecular formula C6H12O6 and is vital to the functioning of cells, especially those in the brain and nervous system.

In the body, glucose is derived from the digestion of carbohydrates in food, and it's transported around the body via the bloodstream to cells where it can be used for energy. Cells convert glucose into a usable form through a process called cellular respiration, which involves a series of metabolic reactions that generate adenosine triphosphate (ATP)—the main currency of energy in cells.

Glucose is also stored in the liver and muscles as glycogen, a polysaccharide (multiple sugar) that can be broken down back into glucose when needed for energy between meals or during physical activity. Maintaining appropriate blood glucose levels is crucial for overall health, and imbalances can lead to conditions such as diabetes mellitus.

Carbon dioxide (CO2) is a colorless, odorless gas that is naturally present in the Earth's atmosphere. It is a normal byproduct of cellular respiration in humans, animals, and plants, and is also produced through the combustion of fossil fuels such as coal, oil, and natural gas.

In medical terms, carbon dioxide is often used as a respiratory stimulant and to maintain the pH balance of blood. It is also used during certain medical procedures, such as laparoscopic surgery, to insufflate (inflate) the abdominal cavity and create a working space for the surgeon.

Elevated levels of carbon dioxide in the body can lead to respiratory acidosis, a condition characterized by an increased concentration of carbon dioxide in the blood and a decrease in pH. This can occur in conditions such as chronic obstructive pulmonary disease (COPD), asthma, or other lung diseases that impair breathing and gas exchange. Symptoms of respiratory acidosis may include shortness of breath, confusion, headache, and in severe cases, coma or death.

Glutarates are compounds that contain a glutaric acid group. Glutaric acid is a carboxylic acid with a five-carbon chain and two carboxyl groups at the 1st and 5th carbon positions. Glutarates can be found in various substances, including certain foods and medications.

In a medical context, glutarates are sometimes used as ingredients in pharmaceutical products. For example, sodium phenylbutyrate, which is a salt of phenylbutyric acid and butyric acid, contains a glutaric acid group and is used as a medication to treat urea cycle disorders.

Glutarates can also be found in some metabolic pathways in the body, where they play a role in energy production and other biochemical processes. However, abnormal accumulation of glutaric acid or its derivatives can lead to certain medical conditions, such as glutaric acidemia type I, which is an inherited disorder of metabolism that can cause neurological symptoms and other health problems.

Mitochondria are specialized structures located inside cells that convert the energy from food into ATP (adenosine triphosphate), which is the primary form of energy used by cells. They are often referred to as the "powerhouses" of the cell because they generate most of the cell's supply of chemical energy. Mitochondria are also involved in various other cellular processes, such as signaling, differentiation, and apoptosis (programmed cell death).

Mitochondria have their own DNA, known as mitochondrial DNA (mtDNA), which is inherited maternally. This means that mtDNA is passed down from the mother to her offspring through the egg cells. Mitochondrial dysfunction has been linked to a variety of diseases and conditions, including neurodegenerative disorders, diabetes, and aging.

Glutamine is defined as a conditionally essential amino acid in humans, which means that it can be produced by the body under normal circumstances, but may become essential during certain conditions such as stress, illness, or injury. It is the most abundant free amino acid found in the blood and in the muscles of the body.

Glutamine plays a crucial role in various biological processes, including protein synthesis, energy production, and acid-base balance. It serves as an important fuel source for cells in the intestines, immune system, and skeletal muscles. Glutamine has also been shown to have potential benefits in wound healing, gut function, and immunity, particularly during times of physiological stress or illness.

In summary, glutamine is a vital amino acid that plays a critical role in maintaining the health and function of various tissues and organs in the body.

Acetoacetates are compounds that are produced in the liver as a part of fatty acid metabolism, specifically during the breakdown of fatty acids for energy. Acetoacetates are formed from the condensation of two acetyl-CoA molecules and are intermediate products in the synthesis of ketone bodies, which can be used as an alternative energy source by tissues such as the brain during periods of low carbohydrate availability or intense exercise.

In clinical settings, high levels of acetoacetates in the blood may indicate a condition called diabetic ketoacidosis (DKA), which is a complication of diabetes mellitus characterized by high levels of ketone bodies in the blood due to insulin deficiency or resistance. DKA can lead to serious complications such as cerebral edema, cardiac arrhythmias, and even death if left untreated.

Oxo-acid lyases are a class of enzymes that catalyze the cleavage of a carbon-carbon bond in an oxo-acid to give a molecule with a carbonyl group and a carbanion, which then reacts non-enzymatically with a proton to form a new double bond. The reaction is reversible, and the enzyme can also catalyze the reverse reaction.

Oxo-acid lyases play important roles in various metabolic pathways, such as the citric acid cycle, glyoxylate cycle, and the degradation of certain amino acids. These enzymes are characterized by the presence of a conserved catalytic mechanism involving a nucleophilic attack on the carbonyl carbon atom of the oxo-acid substrate.

The International Union of Biochemistry and Molecular Biology (IUBMB) has classified oxo-acid lyases under EC 4.1.3, which includes enzymes that catalyze the formation of a carbon-carbon bond by means other than carbon-carbon bond formation to an enolate or carbonion, a carbanionic fragment, or a Michael acceptor.

Oxygen consumption, also known as oxygen uptake, is the amount of oxygen that is consumed or utilized by the body during a specific period of time, usually measured in liters per minute (L/min). It is a common measurement used in exercise physiology and critical care medicine to assess an individual's aerobic metabolism and overall health status.

In clinical settings, oxygen consumption is often measured during cardiopulmonary exercise testing (CPET) to evaluate cardiovascular function, pulmonary function, and exercise capacity in patients with various medical conditions such as heart failure, chronic obstructive pulmonary disease (COPD), and other respiratory or cardiac disorders.

During exercise, oxygen is consumed by the muscles to generate energy through a process called oxidative phosphorylation. The amount of oxygen consumed during exercise can provide important information about an individual's fitness level, exercise capacity, and overall health status. Additionally, measuring oxygen consumption can help healthcare providers assess the effectiveness of treatments and rehabilitation programs in patients with various medical conditions.

Keto acids, also known as ketone bodies, are not exactly the same as "keto acids" in the context of amino acid metabolism.

In the context of metabolic processes, ketone bodies are molecules that are produced as byproducts when the body breaks down fat for energy instead of carbohydrates. When carbohydrate intake is low, the liver converts fatty acids into ketone bodies, which can be used as a source of energy by the brain and other organs. The three main types of ketone bodies are acetoacetate, beta-hydroxybutyrate, and acetone.

However, in the context of amino acid metabolism, "keto acids" refer to the carbon skeletons of certain amino acids that remain after their nitrogen-containing groups have been removed during the process of deamination. These keto acids can then be converted into glucose or used in other metabolic pathways. For example, the keto acid produced from the amino acid leucine is called beta-ketoisocaproate.

Therefore, it's important to clarify the context when discussing "keto acids" as they can refer to different things depending on the context.

Energy metabolism is the process by which living organisms produce and consume energy to maintain life. It involves a series of chemical reactions that convert nutrients from food, such as carbohydrates, fats, and proteins, into energy in the form of adenosine triphosphate (ATP).

The process of energy metabolism can be divided into two main categories: catabolism and anabolism. Catabolism is the breakdown of nutrients to release energy, while anabolism is the synthesis of complex molecules from simpler ones using energy.

There are three main stages of energy metabolism: glycolysis, the citric acid cycle (also known as the Krebs cycle), and oxidative phosphorylation. Glycolysis occurs in the cytoplasm of the cell and involves the breakdown of glucose into pyruvate, producing a small amount of ATP and nicotinamide adenine dinucleotide (NADH). The citric acid cycle takes place in the mitochondria and involves the further breakdown of pyruvate to produce more ATP, NADH, and carbon dioxide. Oxidative phosphorylation is the final stage of energy metabolism and occurs in the inner mitochondrial membrane. It involves the transfer of electrons from NADH and other electron carriers to oxygen, which generates a proton gradient across the membrane. This gradient drives the synthesis of ATP, producing the majority of the cell's energy.

Overall, energy metabolism is a complex and essential process that allows organisms to grow, reproduce, and maintain their bodily functions. Disruptions in energy metabolism can lead to various diseases, including diabetes, obesity, and neurodegenerative disorders.

Acetic acid is an organic compound with the chemical formula CH3COOH. It is a colorless liquid with a pungent, vinegar-like smell and is the main component of vinegar. In medical terms, acetic acid is used as a topical antiseptic and antibacterial agent, particularly for the treatment of ear infections, external genital warts, and nail fungus. It can also be used as a preservative and solvent in some pharmaceutical preparations.

Magnetic Resonance Spectroscopy (MRS) is a non-invasive diagnostic technique that provides information about the biochemical composition of tissues, including their metabolic state. It is often used in conjunction with Magnetic Resonance Imaging (MRI) to analyze various metabolites within body tissues, such as the brain, heart, liver, and muscles.

During MRS, a strong magnetic field, radio waves, and a computer are used to produce detailed images and data about the concentration of specific metabolites in the targeted tissue or organ. This technique can help detect abnormalities related to energy metabolism, neurotransmitter levels, pH balance, and other biochemical processes, which can be useful for diagnosing and monitoring various medical conditions, including cancer, neurological disorders, and metabolic diseases.

There are different types of MRS, such as Proton (^1^H) MRS, Phosphorus-31 (^31^P) MRS, and Carbon-13 (^13^C) MRS, each focusing on specific elements or metabolites within the body. The choice of MRS technique depends on the clinical question being addressed and the type of information needed for diagnosis or monitoring purposes.

Oxidation-Reduction (redox) reactions are a type of chemical reaction involving a transfer of electrons between two species. The substance that loses electrons in the reaction is oxidized, and the substance that gains electrons is reduced. Oxidation and reduction always occur together in a redox reaction, hence the term "oxidation-reduction."

In biological systems, redox reactions play a crucial role in many cellular processes, including energy production, metabolism, and signaling. The transfer of electrons in these reactions is often facilitated by specialized molecules called electron carriers, such as nicotinamide adenine dinucleotide (NAD+/NADH) and flavin adenine dinucleotide (FAD/FADH2).

The oxidation state of an element in a compound is a measure of the number of electrons that have been gained or lost relative to its neutral state. In redox reactions, the oxidation state of one or more elements changes as they gain or lose electrons. The substance that is oxidized has a higher oxidation state, while the substance that is reduced has a lower oxidation state.

Overall, oxidation-reduction reactions are fundamental to the functioning of living organisms and are involved in many important biological processes.

Lactic acid, also known as 2-hydroxypropanoic acid, is a chemical compound that plays a significant role in various biological processes. In the context of medicine and biochemistry, lactic acid is primarily discussed in relation to muscle metabolism and cellular energy production. Here's a medical definition for lactic acid:

Lactic acid (LA): A carboxylic acid with the molecular formula C3H6O3 that plays a crucial role in anaerobic respiration, particularly during strenuous exercise or conditions of reduced oxygen availability. It is formed through the conversion of pyruvate, catalyzed by the enzyme lactate dehydrogenase (LDH), when there is insufficient oxygen to complete the final step of cellular respiration in the Krebs cycle. The accumulation of lactic acid can lead to acidosis and muscle fatigue. Additionally, lactic acid serves as a vital intermediary in various metabolic pathways and is involved in the production of glucose through gluconeogenesis in the liver.

I'm sorry for any confusion, but "Hydro-Lyases" is not a recognized medical term or category in biochemistry. It seems like there might be a misunderstanding or a typo in the term.

In biochemistry, "lyases" are enzymes that catalyze the removal of groups from substrates by means other than hydrolysis or oxidation, often forming a double bond or a ring-forming reaction. They are classified and named based on the type of bond they break.

If you meant to ask about a specific enzyme or reaction, could you please provide more context or clarify the term? I'd be happy to help further with accurate information.

In the context of medical definitions, 'carbon' is not typically used as a standalone term. Carbon is an element with the symbol C and atomic number 6, which is naturally abundant in the human body and the environment. It is a crucial component of all living organisms, forming the basis of organic compounds, such as proteins, carbohydrates, lipids, and nucleic acids (DNA and RNA).

Carbon forms strong covalent bonds with various elements, allowing for the creation of complex molecules that are essential to life. In this sense, carbon is a fundamental building block of life on Earth. However, it does not have a specific medical definition as an isolated term.

Coenzyme A, often abbreviated as CoA or sometimes holo-CoA, is a coenzyme that plays a crucial role in several important chemical reactions in the body, particularly in the metabolism of carbohydrates, fatty acids, and amino acids. It is composed of a pantothenic acid (vitamin B5) derivative called pantothenate, an adenosine diphosphate (ADP) molecule, and a terminal phosphate group.

Coenzyme A functions as a carrier molecule for acetyl groups, which are formed during the breakdown of carbohydrates, fatty acids, and some amino acids. The acetyl group is attached to the sulfur atom in CoA, forming acetyl-CoA, which can then be used as a building block for various biochemical pathways, such as the citric acid cycle (Krebs cycle) and fatty acid synthesis.

In summary, Coenzyme A is a vital coenzyme that helps facilitate essential metabolic processes by carrying and transferring acetyl groups in the body.

Glutamic acid is an alpha-amino acid, which is one of the 20 standard amino acids in the genetic code. The systematic name for this amino acid is (2S)-2-Aminopentanedioic acid. Its chemical formula is HO2CCH(NH2)CH2CH2CO2H.

Glutamic acid is a crucial excitatory neurotransmitter in the human brain, and it plays an essential role in learning and memory. It's also involved in the metabolism of sugars and amino acids, the synthesis of proteins, and the removal of waste nitrogen from the body.

Glutamic acid can be found in various foods such as meat, fish, beans, eggs, dairy products, and vegetables. In the human body, glutamic acid can be converted into gamma-aminobutyric acid (GABA), another important neurotransmitter that has a calming effect on the nervous system.

Aspartic acid is an α-amino acid with the chemical formula HO2CCH(NH2)CO2H. It is one of the twenty standard amino acids, and it is a polar, negatively charged, and hydrophilic amino acid. In proteins, aspartic acid usually occurs in its ionized form, aspartate, which has a single negative charge.

Aspartic acid plays important roles in various biological processes, including metabolism, neurotransmitter synthesis, and energy production. It is also a key component of many enzymes and proteins, where it often contributes to the formation of ionic bonds and helps stabilize protein structure.

In addition to its role as a building block of proteins, aspartic acid is also used in the synthesis of other important biological molecules, such as nucleotides, which are the building blocks of DNA and RNA. It is also a component of the dipeptide aspartame, an artificial sweetener that is widely used in food and beverages.

Like other amino acids, aspartic acid is essential for human health, but it cannot be synthesized by the body and must be obtained through the diet. Foods that are rich in aspartic acid include meat, poultry, fish, dairy products, eggs, legumes, and some fruits and vegetables.

Propionates, in a medical context, most commonly refer to a group of medications that are used as topical creams or gels to treat fungal infections of the skin. Propionic acid and its salts, such as propionate, are the active ingredients in these medications. They work by inhibiting the growth of fungi, which causes the infection. Common examples of propionate-containing medications include creams used to treat athlete's foot, ringworm, and jock itch.

It is important to note that there are many different types of medications and compounds that contain the word "propionate" in their name, as it refers to a specific chemical structure. However, in a medical context, it most commonly refers to antifungal creams or gels.

Perfusion, in medical terms, refers to the process of circulating blood through the body's organs and tissues to deliver oxygen and nutrients and remove waste products. It is a measure of the delivery of adequate blood flow to specific areas or tissues in the body. Perfusion can be assessed using various methods, including imaging techniques like computed tomography (CT) scans, magnetic resonance imaging (MRI), and perfusion scintigraphy.

Perfusion is critical for maintaining proper organ function and overall health. When perfusion is impaired or inadequate, it can lead to tissue hypoxia, acidosis, and cell death, which can result in organ dysfunction or failure. Conditions that can affect perfusion include cardiovascular disease, shock, trauma, and certain surgical procedures.

Biological models, also known as physiological models or organismal models, are simplified representations of biological systems, processes, or mechanisms that are used to understand and explain the underlying principles and relationships. These models can be theoretical (conceptual or mathematical) or physical (such as anatomical models, cell cultures, or animal models). They are widely used in biomedical research to study various phenomena, including disease pathophysiology, drug action, and therapeutic interventions.

Examples of biological models include:

1. Mathematical models: These use mathematical equations and formulas to describe complex biological systems or processes, such as population dynamics, metabolic pathways, or gene regulation networks. They can help predict the behavior of these systems under different conditions and test hypotheses about their underlying mechanisms.
2. Cell cultures: These are collections of cells grown in a controlled environment, typically in a laboratory dish or flask. They can be used to study cellular processes, such as signal transduction, gene expression, or metabolism, and to test the effects of drugs or other treatments on these processes.
3. Animal models: These are living organisms, usually vertebrates like mice, rats, or non-human primates, that are used to study various aspects of human biology and disease. They can provide valuable insights into the pathophysiology of diseases, the mechanisms of drug action, and the safety and efficacy of new therapies.
4. Anatomical models: These are physical representations of biological structures or systems, such as plastic models of organs or tissues, that can be used for educational purposes or to plan surgical procedures. They can also serve as a basis for developing more sophisticated models, such as computer simulations or 3D-printed replicas.

Overall, biological models play a crucial role in advancing our understanding of biology and medicine, helping to identify new targets for therapeutic intervention, develop novel drugs and treatments, and improve human health.

'Aspergillus niger' is a species of fungi that belongs to the genus Aspergillus. It is a ubiquitous microorganism that can be found in various environments, including soil, decaying vegetation, and indoor air. 'Aspergillus niger' is a black-colored mold that produces spores that are easily dispersed in the air.

This fungus is well known for its ability to produce a variety of enzymes and metabolites, some of which have industrial applications. For example, it is used in the production of citric acid, which is widely used as a food additive and preservative.

However, 'Aspergillus niger' can also cause health problems in humans, particularly in individuals with weakened immune systems or underlying lung conditions. It can cause allergic reactions, respiratory symptoms, and invasive aspergillosis, a serious infection that can spread to other organs in the body.

In addition, 'Aspergillus niger' can produce mycotoxins, which are toxic compounds that can contaminate food and feed and cause various health effects in humans and animals. Therefore, it is important to prevent the growth and proliferation of this fungus in indoor environments and food production facilities.

Tricarboxylic acids, also known as TCA cycle or citric acid cycle, is a series of chemical reactions used by all living cells to generate energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins into carbon dioxide and water in the form of ATP. This process is an important part of cellular respiration and occurs in the mitochondria. The cycle involves eight steps that result in the production of two molecules of ATP, reduced coenzymes NADH and FADH2, and the release of three molecules of carbon dioxide.

The tricarboxylic acids involved in this cycle are:

1. Citric acid (also known as citrate)
2. Cis-aconitic acid
3. Isocitric acid
4. Oxalosuccinic acid (an intermediate that is not regenerated)
5. α-Ketoglutaric acid (also known as alpha-ketoglutarate)
6. Succinyl-CoA
7. Succinic acid (also known as succinate)
8. Fumaric acid
9. Malic acid
10. Oxaloacetic acid (also known as oxalacetate)

These acids play a crucial role in the energy production and metabolism of living organisms.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

The myocardium is the middle layer of the heart wall, composed of specialized cardiac muscle cells that are responsible for pumping blood throughout the body. It forms the thickest part of the heart wall and is divided into two sections: the left ventricle, which pumps oxygenated blood to the rest of the body, and the right ventricle, which pumps deoxygenated blood to the lungs.

The myocardium contains several types of cells, including cardiac muscle fibers, connective tissue, nerves, and blood vessels. The muscle fibers are arranged in a highly organized pattern that allows them to contract in a coordinated manner, generating the force necessary to pump blood through the heart and circulatory system.

Damage to the myocardium can occur due to various factors such as ischemia (reduced blood flow), infection, inflammation, or genetic disorders. This damage can lead to several cardiac conditions, including heart failure, arrhythmias, and cardiomyopathy.

NAD (Nicotinamide Adenine Dinucleotide) is a coenzyme found in all living cells. It plays an essential role in cellular metabolism, particularly in redox reactions, where it acts as an electron carrier. NAD exists in two forms: NAD+, which accepts electrons and becomes reduced to NADH. This pairing of NAD+/NADH is involved in many fundamental biological processes such as generating energy in the form of ATP during cellular respiration, and serving as a critical cofactor for various enzymes that regulate cellular functions like DNA repair, gene expression, and cell death.

Maintaining optimal levels of NAD+/NADH is crucial for overall health and longevity, as it declines with age and in certain disease states. Therefore, strategies to boost NAD+ levels are being actively researched for their potential therapeutic benefits in various conditions such as aging, neurodegenerative disorders, and metabolic diseases.

The menstrual cycle is a series of natural changes that occur in the female reproductive system over an approximate 28-day interval, marking the body's preparation for potential pregnancy. It involves the interplay of hormones that regulate the growth and disintegration of the uterine lining (endometrium) and the release of an egg (ovulation) from the ovaries.

The menstrual cycle can be divided into three main phases:

1. Menstrual phase: The cycle begins with the onset of menstruation, where the thickened uterine lining is shed through the vagina, lasting typically for 3-7 days. This shedding occurs due to a decrease in estrogen and progesterone levels, which are hormones essential for maintaining the endometrium during the previous cycle.

2. Follicular phase: After menstruation, the follicular phase commences with the pituitary gland releasing follicle-stimulating hormone (FSH). FSH stimulates the growth of several ovarian follicles, each containing an immature egg. One dominant follicle usually becomes selected to mature and release an egg during ovulation. Estrogen levels rise as the dominant follicle grows, causing the endometrium to thicken in preparation for a potential pregnancy.

3. Luteal phase: Following ovulation, the ruptured follicle transforms into the corpus luteum, which produces progesterone and estrogen to further support the endometrial thickening. If fertilization does not occur within approximately 24 hours after ovulation, the corpus luteum will degenerate, leading to a decline in hormone levels. This drop triggers the onset of menstruation, initiating a new menstrual cycle.

Understanding the menstrual cycle is crucial for monitoring reproductive health and planning or preventing pregnancies. Variations in cycle length and symptoms are common among women, but persistent irregularities may indicate underlying medical conditions requiring further evaluation by a healthcare professional.

A cough is a reflex action that helps to clear the airways of irritants, foreign particles, or excess mucus or phlegm. It is characterized by a sudden, forceful expulsion of air from the lungs through the mouth and nose. A cough can be acute (short-term) or chronic (long-term), and it can be accompanied by other symptoms such as chest pain, shortness of breath, or fever. Coughing can be caused by various factors, including respiratory infections, allergies, asthma, environmental pollutants, gastroesophageal reflux disease (GERD), and chronic lung diseases such as chronic obstructive pulmonary disease (COPD) and bronchitis. In some cases, a cough may be a symptom of a more serious underlying condition, such as heart failure or lung cancer.

In a medical context, taste is the sensation produced when a substance in the mouth reacts with taste buds, which are specialized sensory cells found primarily on the tongue. The tongue's surface contains papillae, which house the taste buds. These taste buds can identify five basic tastes: salty, sour, bitter, sweet, and umami (savory). Different areas of the tongue are more sensitive to certain tastes, but all taste buds can detect each of the five tastes, although not necessarily equally.

Taste is a crucial part of our sensory experience, helping us identify and differentiate between various types of food and drinks, and playing an essential role in appetite regulation and enjoyment of meals. Abnormalities in taste sensation can be associated with several medical conditions or side effects of certain medications.

The Pyruvate Dehydrogenase Complex (PDC) is a multi-enzyme complex that plays a crucial role in cellular energy metabolism. It is located in the mitochondrial matrix and catalyzes the oxidative decarboxylation of pyruvate, the end product of glycolysis, into acetyl-CoA. This reaction links the carbohydrate metabolism (glycolysis) to the citric acid cycle (Krebs cycle), enabling the continuation of energy production in the form of ATP through oxidative phosphorylation.

The Pyruvate Dehydrogenase Complex consists of three main enzymes: pyruvate dehydrogenase (E1), dihydrolipoyl transacetylase (E2), and dihydrolipoyl dehydrogenase (E3). Additionally, two regulatory enzymes are associated with the complex: pyruvate dehydrogenase kinase (PDK) and pyruvate dehydrogenase phosphatase (PDP). These regulatory enzymes control the activity of the PDC through reversible phosphorylation and dephosphorylation, allowing the cell to adapt to varying energy demands and substrate availability.

Deficiencies or dysfunctions in the Pyruvate Dehydrogenase Complex can lead to various metabolic disorders, such as pyruvate dehydrogenase deficiency, which may result in neurological impairments and lactic acidosis due to disrupted energy metabolism.

Lactates, also known as lactic acid, are compounds that are produced by muscles during intense exercise or other conditions of low oxygen supply. They are formed from the breakdown of glucose in the absence of adequate oxygen to complete the full process of cellular respiration. This results in the production of lactate and a hydrogen ion, which can lead to a decrease in pH and muscle fatigue.

In a medical context, lactates may be measured in the blood as an indicator of tissue oxygenation and metabolic status. Elevated levels of lactate in the blood, known as lactic acidosis, can indicate poor tissue perfusion or hypoxia, and may be seen in conditions such as sepsis, cardiac arrest, and severe shock. It is important to note that lactates are not the primary cause of acidemia (low pH) in lactic acidosis, but rather a marker of the underlying process.

Gas Chromatography-Mass Spectrometry (GC-MS) is a powerful analytical technique that combines the separating power of gas chromatography with the identification capabilities of mass spectrometry. This method is used to separate, identify, and quantify different components in complex mixtures.

In GC-MS, the mixture is first vaporized and carried through a long, narrow column by an inert gas (carrier gas). The various components in the mixture interact differently with the stationary phase inside the column, leading to their separation based on their partition coefficients between the mobile and stationary phases. As each component elutes from the column, it is then introduced into the mass spectrometer for analysis.

The mass spectrometer ionizes the sample, breaks it down into smaller fragments, and measures the mass-to-charge ratio of these fragments. This information is used to generate a mass spectrum, which serves as a unique "fingerprint" for each compound. By comparing the generated mass spectra with reference libraries or known standards, analysts can identify and quantify the components present in the original mixture.

GC-MS has wide applications in various fields such as forensics, environmental analysis, drug testing, and research laboratories due to its high sensitivity, specificity, and ability to analyze volatile and semi-volatile compounds.

The liver is a large, solid organ located in the upper right portion of the abdomen, beneath the diaphragm and above the stomach. It plays a vital role in several bodily functions, including:

1. Metabolism: The liver helps to metabolize carbohydrates, fats, and proteins from the food we eat into energy and nutrients that our bodies can use.
2. Detoxification: The liver detoxifies harmful substances in the body by breaking them down into less toxic forms or excreting them through bile.
3. Synthesis: The liver synthesizes important proteins, such as albumin and clotting factors, that are necessary for proper bodily function.
4. Storage: The liver stores glucose, vitamins, and minerals that can be released when the body needs them.
5. Bile production: The liver produces bile, a digestive juice that helps to break down fats in the small intestine.
6. Immune function: The liver plays a role in the immune system by filtering out bacteria and other harmful substances from the blood.

Overall, the liver is an essential organ that plays a critical role in maintaining overall health and well-being.

I'm happy to help! However, it seems like there are two terms combined into one request: "Mitochondria" and "Heart." I will provide separate definitions for each.

Mitochondrion (singular) or Mitochondria (plural): These are specialized structures found in the cytoplasm of most eukaryotic cells (cells with a true nucleus), including human cells. They are often referred to as the "powerhouse" of the cell because they generate energy in the form of ATP (adenosine triphosphate) through a process called oxidative phosphorylation. Mitochondria contain their own DNA, which is distinct from the nuclear DNA, and are believed to have originated from ancient bacteria that established a symbiotic relationship with primitive eukaryotic cells.

Heart: In human anatomy, the heart is a muscular organ responsible for pumping blood throughout the body. It is located in the thoracic cavity, slightly left of the center, and is enclosed by the pericardium, a double-walled sac that provides protection and lubrication for the heart's movement. The human heart is divided into four chambers: two atria on the top and two ventricles on the bottom. The right side of the heart receives deoxygenated blood from the body and pumps it to the lungs, while the left side receives oxygenated blood from the lungs and pumps it to the rest of the body. The heart's pumping action is regulated by electrical signals that originate in a group of specialized cardiac muscle cells called the sinoatrial node (SA node).

Carboxylic acids are organic compounds that contain a carboxyl group, which is a functional group made up of a carbon atom doubly bonded to an oxygen atom and single bonded to a hydroxyl group. The general formula for a carboxylic acid is R-COOH, where R represents the rest of the molecule.

Carboxylic acids can be found in various natural sources such as in fruits, vegetables, and animal products. Some common examples of carboxylic acids include formic acid (HCOOH), acetic acid (CH3COOH), propionic acid (C2H5COOH), and butyric acid (C3H7COOH).

Carboxylic acids have a variety of uses in industry, including as food additives, pharmaceuticals, and industrial chemicals. They are also important intermediates in the synthesis of other organic compounds. In the body, carboxylic acids play important roles in metabolism and energy production.

Culture media is a substance that is used to support the growth of microorganisms or cells in an artificial environment, such as a petri dish or test tube. It typically contains nutrients and other factors that are necessary for the growth and survival of the organisms being cultured. There are many different types of culture media, each with its own specific formulation and intended use. Some common examples include blood agar, which is used to culture bacteria; Sabouraud dextrose agar, which is used to culture fungi; and Eagle's minimum essential medium, which is used to culture animal cells.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Oxidoreductases are a class of enzymes that catalyze oxidation-reduction reactions, which involve the transfer of electrons from one molecule (the reductant) to another (the oxidant). These enzymes play a crucial role in various biological processes, including energy production, metabolism, and detoxification.

The oxidoreductase-catalyzed reaction typically involves the donation of electrons from a reducing agent (donor) to an oxidizing agent (acceptor), often through the transfer of hydrogen atoms or hydride ions. The enzyme itself does not undergo any permanent chemical change during this process, but rather acts as a catalyst to lower the activation energy required for the reaction to occur.

Oxidoreductases are classified and named based on the type of electron donor or acceptor involved in the reaction. For example, oxidoreductases that act on the CH-OH group of donors are called dehydrogenases, while those that act on the aldehyde or ketone groups are called oxidases. Other examples include reductases, peroxidases, and catalases.

Understanding the function and regulation of oxidoreductases is important for understanding various physiological processes and developing therapeutic strategies for diseases associated with impaired redox homeostasis, such as cancer, neurodegenerative disorders, and cardiovascular disease.

"Swine" is a common term used to refer to even-toed ungulates of the family Suidae, including domestic pigs and wild boars. However, in a medical context, "swine" often appears in the phrase "swine flu," which is a strain of influenza virus that typically infects pigs but can also cause illness in humans. The 2009 H1N1 pandemic was caused by a new strain of swine-origin influenza A virus, which was commonly referred to as "swine flu." It's important to note that this virus is not transmitted through eating cooked pork products; it spreads from person to person, mainly through respiratory droplets produced when an infected person coughs or sneezes.

I'd be happy to help! However, I believe there might be a slight misunderstanding in your question. Mitochondria are organelles found in the cells of all complex living organisms, including humans, while the liver is a large, solid organ located in the upper right portion of the abdomen. They don't have a medical definition together. I can certainly provide you with separate definitions for each:

1. Mitochondria: These are double-membrane-bound cellular organelles that generate most of the chemical energy needed to power the cell's biochemical reactions. Commonly known as the "powerhouse of the cell," mitochondria convert organic substrates, such as glucose, fatty acids, and amino acids, into adenosine triphosphate (ATP) through a process called oxidative phosphorylation. Mitochondria are dynamic structures that can change their shape, size, and number through fission (division) and fusion (merging) processes. They play essential roles in various cellular functions, including calcium signaling, apoptosis (programmed cell death), and the regulation of cellular metabolism.

2. Liver: The liver is a large, lobulated organ that lies mainly in the upper right portion of the abdominal cavity, just below the diaphragm. It plays a crucial role in various physiological functions, such as detoxification, protein synthesis, metabolism, and nutrient storage. The liver is responsible for removing toxins from the bloodstream, producing bile to aid in digestion, regulating glucose levels, synthesizing plasma proteins, and storing glycogen, vitamins, and minerals. It also contributes to the metabolism of carbohydrates, lipids, and amino acids, helping maintain energy homeostasis in the body.

I hope this clarifies any confusion! If you have any further questions or need more information, please don't hesitate to ask.

Antitussive agents are medications that are used to suppress cough. They work by numbing the throat and interrupting the cough reflex. Some common antitussives include dextromethorphan, codeine, and hydrocodone. These medications can be found in various over-the-counter and prescription cough and cold products. It is important to use antitussives only as directed, as they can have side effects such as drowsiness, constipation, and slowed breathing. Additionally, it's important to note that long term use of opioid antitussive like codeine and hydrocodone are not recommended due to the risk of addiction and other serious side effects.

Fatty acids are carboxylic acids with a long aliphatic chain, which are important components of lipids and are widely distributed in living organisms. They can be classified based on the length of their carbon chain, saturation level (presence or absence of double bonds), and other structural features.

The two main types of fatty acids are:

1. Saturated fatty acids: These have no double bonds in their carbon chain and are typically solid at room temperature. Examples include palmitic acid (C16:0) and stearic acid (C18:0).
2. Unsaturated fatty acids: These contain one or more double bonds in their carbon chain and can be further classified into monounsaturated (one double bond) and polyunsaturated (two or more double bonds) fatty acids. Examples of unsaturated fatty acids include oleic acid (C18:1, monounsaturated), linoleic acid (C18:2, polyunsaturated), and alpha-linolenic acid (C18:3, polyunsaturated).

Fatty acids play crucial roles in various biological processes, such as energy storage, membrane structure, and cell signaling. Some essential fatty acids cannot be synthesized by the human body and must be obtained through dietary sources.

Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.

Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.

These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.

Adenosine Triphosphate (ATP) is a high-energy molecule that stores and transports energy within cells. It is the main source of energy for most cellular processes, including muscle contraction, nerve impulse transmission, and protein synthesis. ATP is composed of a base (adenine), a sugar (ribose), and three phosphate groups. The bonds between these phosphate groups contain a significant amount of energy, which can be released when the bond between the second and third phosphate group is broken, resulting in the formation of adenosine diphosphate (ADP) and inorganic phosphate. This process is known as hydrolysis and can be catalyzed by various enzymes to drive a wide range of cellular functions. ATP can also be regenerated from ADP through various metabolic pathways, such as oxidative phosphorylation or substrate-level phosphorylation, allowing for the continuous supply of energy to cells.

'Bacillus subtilis' is a gram-positive, rod-shaped bacterium that is commonly found in soil and vegetation. It is a facultative anaerobe, meaning it can grow with or without oxygen. This bacterium is known for its ability to form durable endospores during unfavorable conditions, which allows it to survive in harsh environments for long periods of time.

'Bacillus subtilis' has been widely studied as a model organism in microbiology and molecular biology due to its genetic tractability and rapid growth. It is also used in various industrial applications, such as the production of enzymes, antibiotics, and other bioproducts.

Although 'Bacillus subtilis' is generally considered non-pathogenic, there have been rare cases of infection in immunocompromised individuals. It is important to note that this bacterium should not be confused with other pathogenic species within the genus Bacillus, such as B. anthracis (causative agent of anthrax) or B. cereus (a foodborne pathogen).

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

Taste threshold is the minimum concentration of a taste substance that can be detected by the taste buds. It is the point at which a person can just discriminate the presence of a specific taste (sweet, salty, sour, bitter, or umami) from plain water or another tastant. The taste threshold can be measured through various methods, such as whole-mouth tastings or using specialized taste strips, and it can vary among individuals due to factors like age, genetics, and exposure to certain chemicals or medications.

Amino acids are organic compounds that serve as the building blocks of proteins. They consist of a central carbon atom, also known as the alpha carbon, which is bonded to an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom (H), and a variable side chain (R group). The R group can be composed of various combinations of atoms such as hydrogen, oxygen, sulfur, nitrogen, and carbon, which determine the unique properties of each amino acid.

There are 20 standard amino acids that are encoded by the genetic code and incorporated into proteins during translation. These include:

1. Alanine (Ala)
2. Arginine (Arg)
3. Asparagine (Asn)
4. Aspartic acid (Asp)
5. Cysteine (Cys)
6. Glutamine (Gln)
7. Glutamic acid (Glu)
8. Glycine (Gly)
9. Histidine (His)
10. Isoleucine (Ile)
11. Leucine (Leu)
12. Lysine (Lys)
13. Methionine (Met)
14. Phenylalanine (Phe)
15. Proline (Pro)
16. Serine (Ser)
17. Threonine (Thr)
18. Tryptophan (Trp)
19. Tyrosine (Tyr)
20. Valine (Val)

Additionally, there are several non-standard or modified amino acids that can be incorporated into proteins through post-translational modifications, such as hydroxylation, methylation, and phosphorylation. These modifications expand the functional diversity of proteins and play crucial roles in various cellular processes.

Amino acids are essential for numerous biological functions, including protein synthesis, enzyme catalysis, neurotransmitter production, energy metabolism, and immune response regulation. Some amino acids can be synthesized by the human body (non-essential), while others must be obtained through dietary sources (essential).

Iron-sulfur proteins are a group of metalloproteins that contain iron and sulfur atoms in their active centers. These clusters of iron and sulfur atoms, also known as iron-sulfur clusters, can exist in various forms, including Fe-S, 2Fe-2S, 3Fe-4S, and 4Fe-4S structures. The iron atoms are coordinated to the protein through cysteine residues, while the sulfur atoms can be in the form of sulfide (S2-) or sulfane (-S-).

These proteins play crucial roles in many biological processes, such as electron transfer, redox reactions, and enzyme catalysis. They are found in various organisms, from bacteria to humans, and are involved in a wide range of cellular functions, including energy metabolism, photosynthesis, nitrogen fixation, and DNA repair.

Iron-sulfur proteins can be classified into several categories based on their structure and function, such as ferredoxins, Rieske proteins, high-potential iron-sulfur proteins (HiPIPs), and radical SAM enzymes. Dysregulation or mutations in iron-sulfur protein genes have been linked to various human diseases, including neurodegenerative disorders, cancer, and mitochondrial disorders.

Cell cycle proteins are a group of regulatory proteins that control the progression of the cell cycle, which is the series of events that take place in a eukaryotic cell leading to its division and duplication. These proteins can be classified into several categories based on their functions during different stages of the cell cycle.

The major groups of cell cycle proteins include:

1. Cyclin-dependent kinases (CDKs): CDKs are serine/threonine protein kinases that regulate key transitions in the cell cycle. They require binding to a regulatory subunit called cyclin to become active. Different CDK-cyclin complexes are activated at different stages of the cell cycle.
2. Cyclins: Cyclins are a family of regulatory proteins that bind and activate CDKs. Their levels fluctuate throughout the cell cycle, with specific cyclins expressed during particular phases. For example, cyclin D is important for the G1 to S phase transition, while cyclin B is required for the G2 to M phase transition.
3. CDK inhibitors (CKIs): CKIs are regulatory proteins that bind to and inhibit CDKs, thereby preventing their activation. CKIs can be divided into two main families: the INK4 family and the Cip/Kip family. INK4 family members specifically inhibit CDK4 and CDK6, while Cip/Kip family members inhibit a broader range of CDKs.
4. Anaphase-promoting complex/cyclosome (APC/C): APC/C is an E3 ubiquitin ligase that targets specific proteins for degradation by the 26S proteasome. During the cell cycle, APC/C regulates the metaphase to anaphase transition and the exit from mitosis by targeting securin and cyclin B for degradation.
5. Other regulatory proteins: Several other proteins play crucial roles in regulating the cell cycle, such as p53, a transcription factor that responds to DNA damage and arrests the cell cycle, and the polo-like kinases (PLKs), which are involved in various aspects of mitosis.

Overall, cell cycle proteins work together to ensure the proper progression of the cell cycle, maintain genomic stability, and prevent uncontrolled cell growth, which can lead to cancer.

I believe there may be a slight spelling error in your question. If you are referring to "isocitrate," I can provide a medical definition for that. Isocitrate is a chemical compound that is naturally found in the body and plays a crucial role in energy production within cells. It is a key intermediate in the citric acid cycle, also known as the Krebs cycle or tricarboxylic acid (TCA) cycle, which is a series of chemical reactions used by all living cells to generate energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins into adenosine triphosphate (ATP).

Isocitrate is an important molecule in this cycle as it undergoes oxidative decarboxylation, catalyzed by the enzyme isocitrate dehydrogenase, to form alpha-ketoglutarate. This reaction also produces nicotinamide adenine dinucleotide (NADH), which serves as an essential electron carrier in the generation of ATP during oxidative phosphorylation.

If you meant something else or need more information, please let me know, and I will be happy to help.

I apologize for any confusion, but "Osmeriformes" is not a medical term. It is a term used in the field of biology, specifically in fish taxonomy. Osmeriformes is an order of ray-finned fishes that includes species such as salmon, trout, and smelts. These fish are characterized by their elongated, slender bodies and specialized mouthparts adapted for surface feeding. I hope this clarifies any confusion!

Aconitic acid is a type of organic acid that is found naturally in some plants, including Aconitum napellus (monkshood or wolf's bane). It is a white crystalline powder with a sour taste and is soluble in water. In the human body, aconitic acid is produced as a byproduct of energy metabolism and can be found in small amounts in various tissues.

Aconitic acid has three carboxylic acid groups, making it a triprotic acid, which means that it can donate three protons (hydrogen ions) in solution. It is a strong acid and is often used as a laboratory reagent for various chemical reactions. In the food industry, aconitic acid may be used as a food additive or preservative.

It's important to note that some species of Aconitum plants contain highly toxic compounds called aconitines, which can cause serious harm or even death if ingested. Therefore, these plants should not be consumed or handled without proper knowledge and precautions.

Root canal irrigants are substances used during root canal treatment to clean, disinfect and rinse the root canal system. The main goal is to remove tissue remnants, dentinal debris, and microorganisms from the root canal space, thus reducing the risk of reinfection and promoting healing. Commonly used irrigants include sodium hypochlorite (NaOCl), which is a potent antimicrobial agent, and ethylenediaminetetraacetic acid (EDTA), which is used to remove the smear layer and improve the penetration of other irrigants and root canal sealers. The choice of irrigant, concentration, and application technique may vary depending on the specific case and clinician's preference.

Metacercariae are the encysted, infective stage of certain trematode (flatworm) parasites, such as those that cause intestinal schistosomiasis and fascioliasis. They form following a series of developmental stages within intermediate hosts like snails, fish, or crustaceans. Once ingested by the definitive host (usually a mammal), metacercariae excyst in the digestive tract and migrate to their target organs, where they mature into adults and reproduce.

Quinine is defined as a bitter crystalline alkaloid derived from the bark of the Cinchona tree, primarily used in the treatment of malaria and other parasitic diseases. It works by interfering with the reproduction of the malaria parasite within red blood cells. Quinine has also been used historically as a muscle relaxant and analgesic, but its use for these purposes is now limited due to potential serious side effects. In addition, quinine can be found in some beverages like tonic water, where it is present in very small amounts for flavoring purposes.

"Inbred strains of rats" are genetically identical rodents that have been produced through many generations of brother-sister mating. This results in a high degree of homozygosity, where the genes at any particular locus in the genome are identical in all members of the strain.

Inbred strains of rats are widely used in biomedical research because they provide a consistent and reproducible genetic background for studying various biological phenomena, including the effects of drugs, environmental factors, and genetic mutations on health and disease. Additionally, inbred strains can be used to create genetically modified models of human diseases by introducing specific mutations into their genomes.

Some commonly used inbred strains of rats include the Wistar Kyoto (WKY), Sprague-Dawley (SD), and Fischer 344 (F344) rat strains. Each strain has its own unique genetic characteristics, making them suitable for different types of research.

Gene expression regulation in bacteria refers to the complex cellular processes that control the production of proteins from specific genes. This regulation allows bacteria to adapt to changing environmental conditions and ensure the appropriate amount of protein is produced at the right time.

Bacteria have a variety of mechanisms for regulating gene expression, including:

1. Operon structure: Many bacterial genes are organized into operons, which are clusters of genes that are transcribed together as a single mRNA molecule. The expression of these genes can be coordinately regulated by controlling the transcription of the entire operon.
2. Promoter regulation: Transcription is initiated at promoter regions upstream of the gene or operon. Bacteria have regulatory proteins called sigma factors that bind to the promoter and recruit RNA polymerase, the enzyme responsible for transcribing DNA into RNA. The binding of sigma factors can be influenced by environmental signals, allowing for regulation of transcription.
3. Attenuation: Some operons have regulatory regions called attenuators that control transcription termination. These regions contain hairpin structures that can form in the mRNA and cause transcription to stop prematurely. The formation of these hairpins is influenced by the concentration of specific metabolites, allowing for regulation of gene expression based on the availability of those metabolites.
4. Riboswitches: Some bacterial mRNAs contain regulatory elements called riboswitches that bind small molecules directly. When a small molecule binds to the riboswitch, it changes conformation and affects transcription or translation of the associated gene.
5. CRISPR-Cas systems: Bacteria use CRISPR-Cas systems for adaptive immunity against viruses and plasmids. These systems incorporate short sequences from foreign DNA into their own genome, which can then be used to recognize and cleave similar sequences in invading genetic elements.

Overall, gene expression regulation in bacteria is a complex process that allows them to respond quickly and efficiently to changing environmental conditions. Understanding these regulatory mechanisms can provide insights into bacterial physiology and help inform strategies for controlling bacterial growth and behavior.

A smear layer is a thin, amorphous layer of debris that forms on the dentin surface when it comes into contact with instruments or solutions during dental procedures such as cavity preparation, root canal treatment, or biopsies. This layer is composed of organic and inorganic components, including dentinal cuttings, pulp tissue, bacteria, and materials from the irrigating solution. The smear layer can occlude the dentinal tubules, affecting the adhesion of filling materials and sealing ability of obturation points. Therefore, it is often removed during root canal preparation using various methods such as chemical dissolution, ultrasonic agitation, or laser ablation to ensure proper disinfection and seal of the root canal system.

'Acetobacter' is a genus of gram-negative, aerobic, rod-shaped bacteria that are commonly found in various environments such as soil, water, and plant surfaces. They are known for their ability to oxidize alcohols to aldehydes and then to carboxylic acids, particularly the oxidation of ethanol to acetic acid. This property makes them important in the production of vinegar and other fermented foods. Some species of Acetobacter can also cause food spoilage and may be associated with certain human infections, although they are not considered primary human pathogens.

"Caproates" is not a term commonly used in medical terminology. It appears to be a derivative of "caproic acid," which is an organic compound with the formula CH3CH2CH2CH2CO2H. Caproic acid is one of several saturated fatty acids that are abundant in animal fats and have a distinctive rancid odor when they spoil or break down.

However, I was unable to find any specific medical definition or use of the term "caproates" in the context of medicine or healthcare. It is possible that this term may be used in a different field or context, such as chemistry or biochemistry. If you have more information about the context in which you encountered this term, I may be able to provide a more accurate answer.

The estrous cycle is the reproductive cycle in certain mammals, characterized by regular changes in the reproductive tract and behavior, which are regulated by hormonal fluctuations. It is most commonly observed in non-primate mammals such as dogs, cats, cows, pigs, and horses.

The estrous cycle consists of several stages:

1. Proestrus: This stage lasts for a few days and is characterized by the development of follicles in the ovaries and an increase in estrogen levels. During this time, the female may show signs of sexual receptivity, but will not allow mating to occur.
2. Estrus: This is the period of sexual receptivity, during which the female allows mating to take place. It typically lasts for a few days and is marked by a surge in luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which triggers ovulation.
3. Metestrus: This stage follows ovulation and is characterized by the formation of a corpus luteum, a structure that produces progesterone to support pregnancy. If fertilization does not occur, the corpus luteum will eventually regress, leading to the next phase.
4. Diestrus: This is the final stage of the estrous cycle and can last for several weeks or months. During this time, the female's reproductive tract returns to its resting state, and she is not sexually receptive. If pregnancy has occurred, the corpus luteum will continue to produce progesterone until the placenta takes over this function later in pregnancy.

It's important to note that the human menstrual cycle is different from the estrous cycle. While both cycles involve hormonal fluctuations and changes in the reproductive tract, the menstrual cycle includes a shedding of the uterine lining (menstruation) if fertilization does not occur, which is not a feature of the estrous cycle.

'Escherichia coli' (E. coli) is a type of gram-negative, facultatively anaerobic, rod-shaped bacterium that commonly inhabits the intestinal tract of humans and warm-blooded animals. It is a member of the family Enterobacteriaceae and one of the most well-studied prokaryotic model organisms in molecular biology.

While most E. coli strains are harmless and even beneficial to their hosts, some serotypes can cause various forms of gastrointestinal and extraintestinal illnesses in humans and animals. These pathogenic strains possess virulence factors that enable them to colonize and damage host tissues, leading to diseases such as diarrhea, urinary tract infections, pneumonia, and sepsis.

E. coli is a versatile organism with remarkable genetic diversity, which allows it to adapt to various environmental niches. It can be found in water, soil, food, and various man-made environments, making it an essential indicator of fecal contamination and a common cause of foodborne illnesses. The study of E. coli has contributed significantly to our understanding of fundamental biological processes, including DNA replication, gene regulation, and protein synthesis.

In medical terms, the heart is a muscular organ located in the thoracic cavity that functions as a pump to circulate blood throughout the body. It's responsible for delivering oxygen and nutrients to the tissues and removing carbon dioxide and other wastes. The human heart is divided into four chambers: two atria on the top and two ventricles on the bottom. The right side of the heart receives deoxygenated blood from the body and pumps it to the lungs, while the left side receives oxygenated blood from the lungs and pumps it out to the rest of the body. The heart's rhythmic contractions and relaxations are regulated by a complex electrical conduction system.

Taste perception refers to the ability to recognize and interpret different tastes, such as sweet, salty, sour, bitter, and umami, which are detected by specialized sensory cells called taste buds located on the tongue and other areas in the mouth. These taste signals are then transmitted to the brain, where they are processed and identified as specific tastes. Taste perception is an important sense that helps us to appreciate and enjoy food, and it also plays a role in our ability to detect potentially harmful substances in our diet.

The metabolome is the complete set of small molecule metabolites, such as carbohydrates, lipids, nucleic acids, and amino acids, present in a biological sample at a given moment. It reflects the physiological state of a cell, tissue, or organism and provides information about the biochemical processes that are taking place. The metabolome is dynamic and constantly changing due to various factors such as genetics, environment, diet, and disease. Studying the metabolome can help researchers understand the underlying mechanisms of health and disease and develop diagnostic tools and treatments for various medical conditions.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

I'm sorry for any confusion, but "Stars, Celestial" is not a medical term. The term "stars" or "celestial bodies" is used in astronomy to refer to large, luminous spheres of plasma held together by gravity. They produce light and heat from the fusion of hydrogen into helium at their cores.

If you have any questions related to medical terminology, I'd be happy to help!

Sucrose is a type of simple sugar, also known as a carbohydrate. It is a disaccharide, which means that it is made up of two monosaccharides: glucose and fructose. Sucrose occurs naturally in many fruits and vegetables and is often extracted and refined for use as a sweetener in food and beverages.

The chemical formula for sucrose is C12H22O11, and it has a molecular weight of 342.3 g/mol. In its pure form, sucrose is a white, odorless, crystalline solid that is highly soluble in water. It is commonly used as a reference compound for determining the sweetness of other substances, with a standard sucrose solution having a sweetness value of 1.0.

Sucrose is absorbed by the body through the small intestine and metabolized into glucose and fructose, which are then used for energy or stored as glycogen in the liver and muscles. While moderate consumption of sucrose is generally considered safe, excessive intake can contribute to weight gain, tooth decay, and other health problems.

Tartrates are salts or esters of tartaric acid, a naturally occurring organic acid found in many fruits, particularly grapes. In a medical context, potassium bitartrate (also known as cream of tartar) is sometimes used as a mild laxative or to treat acidosis by helping to restore the body's normal pH balance. Additionally, sodium tartrate has been historically used as an antidote for lead poisoning. However, these uses are not common in modern medicine.

In medical terms, the tongue is a muscular organ in the oral cavity that plays a crucial role in various functions such as taste, swallowing, and speech. It's covered with a mucous membrane and contains papillae, which are tiny projections that contain taste buds to help us perceive different tastes - sweet, salty, sour, and bitter. The tongue also assists in the initial process of digestion by moving food around in the mouth for chewing and mixing with saliva. Additionally, it helps in forming words and speaking clearly by shaping the sounds produced in the mouth.

The Pentose Phosphate Pathway (also known as the Hexose Monophosphate Shunt or HMP Shunt) is a metabolic pathway that runs parallel to glycolysis. It serves two major functions:

1. Providing reducing equivalents in the form of NADPH for reductive biosynthesis and detoxification processes.
2. Generating ribose-5-phosphate, a pentose sugar used in the synthesis of nucleotides and nucleic acids (DNA and RNA).

This pathway begins with the oxidation of glucose-6-phosphate to form 6-phosphogluconolactone, catalyzed by the enzyme glucose-6-phosphate dehydrogenase. The resulting NADPH is used in various anabolic reactions and antioxidant defense systems.

The Pentose Phosphate Pathway also includes a series of reactions called the non-oxidative branch, which interconverts various sugars to meet cellular needs for different types of monosaccharides. These conversions are facilitated by several enzymes including transketolase and transaldolase.

Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.

Hydrogen-ion concentration, also known as pH, is a measure of the acidity or basicity of a solution. It is defined as the negative logarithm (to the base 10) of the hydrogen ion activity in a solution. The standard unit of measurement is the pH unit. A pH of 7 is neutral, less than 7 is acidic, and greater than 7 is basic.

In medical terms, hydrogen-ion concentration is important for maintaining homeostasis within the body. For example, in the stomach, a high hydrogen-ion concentration (low pH) is necessary for the digestion of food. However, in other parts of the body such as blood, a high hydrogen-ion concentration can be harmful and lead to acidosis. Conversely, a low hydrogen-ion concentration (high pH) in the blood can lead to alkalosis. Both acidosis and alkalosis can have serious consequences on various organ systems if not corrected.

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... leading to the citric acid cycle and allowing for the production of amino acids. GlcN-6-P and fructose-6-phosphate act as ... Stryer L, Tymoczko JL, Berg JM (2002). "The Citric Acid Cycle". Biochemistry. 5th Edition. White RJ, Pasternak CA (October 1967 ... Asp-273 then acts as an acid to protonate the amine leaving group. One proposed mechanism using the BsNagA and its two iron co- ... The mechanism proceeds via a strictly conserved active-site aspartic acid residue (Asp-273) that acts initially as a base to ...
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"The Citric Acid Cycle". Biochemistry. 5th Edition. Jordan, Frank; Furey, William; Nemeria, Natalia S.; Patel, Mulchand S. (2014 ... Energy-generating ions and molecules, such as amino acids and carbohydrates, enter the Krebs cycle as acetyl coenzyme A and ... As the Krebs cycle occurs in the mitochondrial matrix, the pyruvate generated during glycolysis in the cytosol is transported ... CO2 Pyruvate oxidation is the step that connects glycolysis and the Krebs cycle. In glycolysis, a single glucose molecule (6 ...
Voet DJ, Voet JG, Pratt CW (2010). "Chapter 17, Citric Acid Cycle". Principles of Biochemistry (4th ed.). Wiley. p. 550. ISBN ... The PDHB gene encodes a precursor protein that has 359 amino acid residues and a final mature protein that has 329 amino acids ... and provides the primary link between glycolysis and the tricarboxylic acid (TCA) cycle. The PDH complex is composed of ... In forming the entire PDH complex, the 289th beta residue, aspartic acid, interacts with the 276th residue of the E2 complex, a ...
Voet DJ, Voet JG, Pratt CW (2010). "Chapter 17, Citric Acid Cycle". Principles of Biochemistry (4th ed.). Wiley. p. 550. ISBN ... Pyruvate dehydrogenase deficiency is characterized by the buildup of a chemical called lactic acid in the body and a variety of ... The most common feature is a potentially life-threatening buildup of lactic acid (lactic acidosis), which can cause nausea, ...
Voet DJ, Voet JG, Pratt CW (2010). "Chapter 17, Citric Acid Cycle". Principles of Biochemistry (4th ed.). Wiley. p. 550. ISBN ... The PDHA1 subunit has been shown to be regulated by free fatty acids during bouts of exercise. The presence of free fatty acids ... The preliminary peptide encoded by this gene was 29 amino acids at the very start of the sequence that correspond to a typical ... Pyruvate dehydrogenase deficiency is characterized by the buildup of a chemical called lactic acid in the body and a variety of ...
November 22 - Hans Krebs (b. 1900), German medical doctor and biochemist; discoverer of the citric acid cycle. December 6 - ...
Krebs cycle - also known as the TCA cycle or Citric acid cycle - is a biochemical pathway that facilitates the breakdown of ... "6.2: Citric Acid Cycle & Related Pathways". Biology LibreTexts. 2017-01-21. Retrieved 2022-03-28. Voet, Donald (2013). ... Wikipedia articles with style issues from September 2023, All articles with style issues, Metabolism, Citric acid cycle). ... The shuttle also helps the production of fatty acid and lactic acid. In liver cancer cells, the TCA cycle is blocked, causing ...
This enzyme participates in citric acid cycle. Lill U, Schreil A, Eggerer H (1982). "Isolation of enzymically active fragments ... This enzyme belongs to the family of ligases, specifically those forming carbon-sulfur bonds as acid-thiol ligases. The ...
Malfunction of the citric acid cycle due to PDH deficiency deprives the body of energy and leads to an abnormal buildup of ... The conversion is crucial because acetyl-CoA may then be used in the citric acid cycle to carry out cellular respiration. To ... Ochoa S (1954). "Enzymic Mechanisms in the Citric Acid Cycle". Advances in Enzymology and Related Areas of Molecular Biology. ... and through hydrogen bonding to amino acids. While over 20 amino acids can be found in the active site, amino acids Tyr 89, Arg ...
kingdom Krebs cycle See citric acid cycle. larva (pl.) larvae A distinct juvenile form many animals undergo before ... cilia circadian rhythm citric acid cycle A series of chemical reactions used by all aerobic organisms to generate energy ... by which the NADH and succinate generated by the citric acid cycle are oxidized and electrons are transferred sequentially down ... including amino acids and nucleic acids. nucleic acid The biopolymers, or small biomolecules, essential to all known forms of ...
... to succinyl-CoA and CO2 during the citric acid cycle. The reaction catalyzed by OGDH is a rate-limiting step in the citric acid ... PDH links glycolysis to the citric acid cycle. OGDH catalyzes the overall conversion of 2-oxoglutarate (alpha-ketoglutarate) ... Thiamine and its metabolites (2-methyl-4-amino-5-pyrimidine carboxylic acid, 4-methyl-thiazole-5-acetic acid, and others) are ... The best-characterized form is TPP, a coenzyme in the catabolism of sugars and amino acids. While its role is well-known, the ...
This enzyme participates in the Citric acid cycle. Some forms catalyze the reverse reaction within the Reverse Krebs cycle, as ... Mai X, Adams MW (1996). "Characterization of a fourth type of 2-keto acid-oxidizing enzyme from a hyperthermophilic archaeon: 2 ... Schut GJ, Menon AL, Adams MW (2001). "2-keto acid oxidoreductases from Pyrococcus furiosus and Thermococcus litoralis". Methods ...
3.0.CO;2-6. Sokic-Lazic, Daria; Minteer, Shelley D. (December 2008). "Citric acid cycle biomimic on a carbon electrode". ... Phenothiazine is used as an anaerobic inhibitor for acrylic acid polymerization, often used as an in-process inhibitor during ... Levy, Leon B. (1992-03-30). "Inhibition of acrylic acid polymerization by phenothiazine and p‐methoxyphenol. II. Catalytic ... the purification of acrylic acid. Like many commercially significant compounds, phenothiazine has numerous trade names, ...
Fluoroacetate, in the citric acid cycle, can innocently enter as fluorocitrate. However, aconitase cannot bind this substrate ... Citric acid Aconitic acid Isocitric acid Aconitase, displayed in the structures in the right margin of this page, has two ... Takusagawa F. "Chapter 16: Citric Acid Cycle" (PDF). Takusagawa's Note. The University of Kansas. Archived from the original ( ... and thus the citric acid cycle is halted. The iron sulfur cluster is highly sensitive to oxidation by superoxide. Aconitase ...
Due to the truncation of the citric acid cycle the amount of acetyl-CoA infiltrated in the citric acid cycle is low and acetyl- ... Citric acid cycle Malate-aspartate shuttle Krebs, HA; Bellamy D (1960). "The interconversion of glutamic acid and aspartic acid ... In tumor cells the citric acid cycle is truncated due to an inhibition of the enzyme aconitase (EC 4.2.1.3) by high ... Glutaminolysis partially recruits reaction steps from the citric acid cycle and the malate-aspartate shuttle. The conversion of ...
Lambeth DO (2002). "What is the function of GTP produced in the Krebs citric acid cycle?". IUBMB Life. 54 (3): 143-4. doi: ... Occurs in glycolysis and in the citric acid cycle. Unlike oxidative phosphorylation, oxidation and phosphorylation are not ... phosphorylation occurs in the cytoplasm of cells during glycolysis and in mitochondria either during the Krebs cycle or by ...
Oxaloacetate, which enters the citric acid cycle (Krebs cycle). Heating a mixture of asparagine and reducing sugars or other ... Proteinogenic amino acids, Glucogenic amino acids, Carboxamides, Alpha-Amino acids). ... that asparagine and aspartic acid itself are decomposed with a remarkable ease under the influence of nitrous acid, rendering ... Asparagine (symbol Asn or N) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group ( ...
Catabolism does not involve a complete citric acid cycle. Some species of the Methylococcaceae have formed with certain marine ... Methane is oxidized to give formaldehyde, which is fixed by a process called the ribulose monophosphate (RuMP) cycle. Here ...
Citrate is an intermediate in the citric acid cycle, also known as the TCA (TriCarboxylic Acid) cycle or the Krebs cycle, a ... Citric acid can be used as an alternative to nitric acid in passivation of stainless steel. Citric acid can be used as a lower- ... Citric acid is an alpha hydroxy acid and is an active ingredient in chemical skin peels. Citric acid is commonly used as a ... Citric acid/potassium-sodium citrate can be used as a blood acid regulator. The citric acid is included to improve palatability ...
... is a substrate of the citric acid cycle. It is acted upon by isocitrate dehydrogenase. Salts and esters of ... Oxalosuccinic acid/oxalosuccinate is an unstable 6-carbon intermediate in the tricarboxylic acid cycle. It's a keto acid, ... Tricarboxylic acids, Alpha-keto acids, Beta-keto acids, All stub articles, Biochemistry stubs). ... Oxalosuccinic acid is both an alpha-keto and a beta-keto acid (an unstable compound) and it is the beta-ketoic property that ...
... the reverse TCA cycle, or the reverse citric acid cycle, or the reductive tricarboxylic acid cycle, or the reductive TCA cycle ... The reaction is the citric acid cycle run in reverse. Where the Krebs cycle takes carbohydrates and oxidizes them to CO2 and ... In contrast to the oxidative citric acid cycle, the reverse or reductive cycle has a few key differences. There are three ... In addition, these organisms that undergo photochemistry can and do utilize the citric acid cycle. However, the conditions are ...
... is a cofactor for at least five enzyme systems. Two of these are in the citric acid cycle through which many ... Lipoic acid (LA), also known as α-lipoic acid, alpha-lipoic acid (ALA) and thioctic acid, is an organosulfur compound derived ... Lipoic acid (LA), also known as α-lipoic acid, alpha-lipoic acid (ALA), and thioctic acid is an organosulfur compound derived ... The first two are critical to the citric acid cycle. The GCS regulates glycine concentrations. HDAC1, HDAC2, HDAC3, HDAC6, ...
Oxaloacetate is a metabolic intermediate of the citric acid cycle. In the short-lived roundworm Caenorhabditis elegans, ... Lipoic Acid (α-Lipoic Acid, Alpha Lipoic Acid, or ALA) has failed to extend lifespan in normal mice or rats in numerous studies ... Lee CK, Pugh TD, Klopp RG, Edwards J, Allison DB, Weindruch R, Prolla TA (Apr 15, 2004). "The impact of alpha-lipoic acid, ... Merry BJ, Kirk AJ, Goyns MH (June 2008). "Dietary lipoic acid supplementation can mimic or block the effect of dietary ...
... where further energy can be extracted through the citric acid cycle (CAC) (see below, c.f. bioenergetic systems). The liver can ... the pyruvate not converted feeds the citric acid cycle (CAC); both via pyruvate dehydrogenase (PDC, with Acetyl-CoA as ... "SOLUTE CARRIER FAMILY 16 (MONOCARBOXYLIC ACID TRANSPORTER), MEMBER 1; SLC16A1". www.omim.org. Retrieved 2023-08-22. Brown GK, ... cells also use the enzyme acid alpha-glucosidase in lysosomes to degrade glycogen. A deficiency of an involved enzyme results ...
... which plays an essential role in the tricarboxylic acid cycle (aka the Citric Acid Cycle, or Krebs Cycle). The compound is ... In this way, the compound enters the Citric Acid Cycle. The following diagram demonstrates the aforementioned reaction: ... which converts toxic methylmalonic acid to methylmalonyl-CoA and thus supplies it to the citrate cycle. The result is an ... This causes a buildup of propionic and/or methylmalonic acid, which has effects on infants ranging from severe brain damage to ...
The enzyme is inhibited and the cycle stops working. Citric acid Fluoroacetic acid Citrate cycle H., Garrett, Reginald (2013). ... Fluorocitric acid is a fluorinated carboxylic acid derived from citric acid by substitution of one hydrogen by a fluorine atom ... Fluorocitric acid Archived 2016-03-04 at the Wayback Machine The Chemical and Biochemical Properties of Fluorocitric Acid Pdf v ... Tricarboxylic acids, Organofluorides, Fluorohydrins, Respiratory toxins, Aconitase inhibitors, Fluorinated carboxylic acids, ...
... citric acid cycle, tricarboxylic acid cycle); Caesar's Armies Invaded Other Kingdoms Searching For Many Oranges. Citric Acid Is ... This method begins with the two amino acids that need some qualifications as to their requirements. To remember Krebs cycle ( ... MATT VIL PLy Essential amino acids Archived 2010-08-26 at the Wayback Machine Essential amino acids, Mnemonic. Williams, R.A.D ... These Ten Valuable Acids Have Long Preserved Life In Men MATT HILL, VP LIFT HIM KIW(V)I TV FILM HW(R)K. Any Help In Learning ...
... aka Krebs or citric acid cycle) (Q27436670). An animation of the citric acid cycle at Smith College Citric acid cycle variants ... The citric acid cycle -also known as the Krebs cycle, Szent-Györgyi-Krebs cycle or the TCA cycle (tricarboxylic acid cycle)-is ... However, because of the role of the citric acid cycle in anabolism, they might not be lost, since many citric acid cycle ... For each acetyl group that enters the citric acid cycle, three molecules of NADH are produced. The citric acid cycle includes a ...
Learn Citric Acid Cycle 4 with free step-by-step video explanations and practice problems by experienced tutors. ... And then youre actually gonna produce 20 from the citric acid cycle. Big money, right? Thats why citric acid cycle, um, and ... Now lets talk a little bit about regulation of the citric acid cycle. Generally speaking, the citric acid cycle is regulated ... er molecules from the citric acid cycle. So the molecules of the citric acid cycle, like Alfa Kita glued a rate section eight. ...
... a unidirectional cycle with carboxylic acids. The original concept of the Citric Acid Cycle from Krebs 1953 Nobel Prize ... lecture illustrates the unidirectional degradation of lactic acid to water, carbon dioxide and hydrogen. Here, we ad … ... A Krebs first published the Citric Acid Cycle, ... Keywords: Citric Acid Cycle; exercise; malic acid; memory ... D) The Citric Acid Cycle 1.1 makes the dynamics clear. If lactic acid is not "burned," the import of lactic acid into the cycle ...
To support you, weve prepared a comprehensive overview of the citric acid cycle for the MCAT exam. ... The citric acid cycle is one of many MCAT subjects that you need to be aware of for the MCAT exam. It forms part of the ... Citric acid cycle: background. The citric acid cycle plays a critical part in cellular aerobic respiration, converting citric ... Citric Acid Cycle for the MCAT: FAQS. Still have questions about the citric acid cycle for the MCAT? Below youll find answers ...
Citric Acid Cycle (+Mechanisms) by Chris Ma - November 22, 2016 ...
Citric acid cycle importance, definition, steps, products, location & inhibitors The citric acid cycle is a part of cellular ...
The Citric Acid Cycle flashcards. Play games, take quizzes, print and more with Easy Notecards. ... the citric acid cycle.. B) In the glyoxylate cycle, the two decarboxylation reactions of the citric acid cycle are bypassed, ... B) The rate of the citric acid cycle increases when the NAD+/NADH ratio is high.. C) In eukaryotes, the citric acid cycle ... Intermediates in the citric acid cycle are used as precursors in the biosynthesis of:. A) amino acids.. B) nucleotides.. C) ...
... also known as the tricarboxylic acid (TCA) cycle or the Krebs cycle - is a series of chemical reactions used by all aer... , ... Solved): The citric acid cycle (CAC) - also known as the tricarboxylic acid (TCA) cycle or the Krebs cycle - ... ... The citric acid cycle (CAC) - also known as the tricarboxylic acid (TCA) cycle or the Krebs cycle - is a series of chemical ... Home / Expert Answers / Biology / the-citric-acid-cycle-cac-also-known-as-the-tricarboxylic-acid-tca-cycle-or-the-krebs-cycle- ...
Citric acid cycle. Biochemistry. 2nd ed. San Francisco, CA: Freeman; 1981. 290-5. ... Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin and ...
... succinic acid (c) citric acid (d) acetyl CoA. Description : Link between glycolysis, Krebs cycle and β-oxidation of fatty acid ... c) The cycle starts with condensation of acetyl group (acetyl CoA) with pyruvic acid to yield citric acid. (d) There are three ... fumaric acid to malic acid (b) succinic acid to fumaric acid (c) succinyl CoA to succinic acid (d) α-ketoglutarate to succinyl ... fumaric acid to malic acid (b) succinic acid to fumaric acid (c) succinyl CoA to succinic acid (d) α-ketoglutarate to succinyl ...
Evaluation of carbon flux and substrate selection through alternate pathways involving the citric acid cycle of the heart by 13 ... Evaluation of carbon flux and substrate selection through alternate pathways involving the citric acid cycle of the heart by 13 ...
Citric Acid Cycle Explore More Trending Topics NBA Marvel Disney Harry Potter ...
... which outcompetes glucose and glutamine-derived carbon in PDAC to fuel the tricarboxylic acid (TCA) cycle, and thus NEAA and ... are critical for PDAC metabolism through the secretion of non-essential amino acids (NEAA). Specifically, we uncover a ...
REACTOME_PYRUVATE_METABOLISM_AND_CITRIC_ACID_TCA_CYCLE. 39. −2.30. ,0.001. REACTOME_CTNNB1_PHOSPHORYLATION_CASCADE. 15. −2.28. ... REACTOME_TRANSPORT_OF_GLUCOSE_AND_OTHER_SUGARS_BILE_SALTS_AND_ORGANIC_ACIDS_METAL_IONS_AND_AMINE_COMPOUNDS. 76. −2.36. ,0.001. ... REACTOME_FATTY_ACID_TRIACYLGLYCEROL_AND_KETONE_BODY_METABOLISM. 151. −2.24. 1.55E-04. ... POSITIVE_REGULATION_OF_NUCLEOBASENUCLEOSIDENUCLEOTIDE_AND_NUCLEIC_ACID_METABOLIC_PROCESS. 143. 1.68. 0.042. ...
The citric acid cycle, also known as the Krebs cycle, is a series of chemical reactions that occur in the mitochondria of cells ... However, the citric acid cycle does not directly involve the addition of electrons and protons to oxygen to form water. This ... This process occurs in the presence of oxygen and involves several stages, including glycolysis, the citric acid cycle, and ... All of the following are functions of the citric acid cycle except. *. A. ...
... tion of acid etching. Orig. air date: NOV 27 74 This is part of the Open.Michigan collection... ... Lec 14 - Class IV Composite - Acid Etch A complete class IV composite restoration with demonstra- ... Citric Acid Cycle or Krebs Cycle. 00:00 , 13636 views Watch VIDEO. 10913 views ... Lec 14 - Class IV Composite - Acid Etch "Lec 14 - Class IV Composite - Acid Etch" A complete class IV composite restoration ...
Glycolysis, citric acid cycle and electron transport. Glycogen metabolism, pentose-phosphate pathway, gluconeogenesis and ... The urea cycle, nitrogen excretion. Practical training in scientific writing skills: evaluation of a scientific report. ... Hydrological cycles and the soil water balance. Sustainable crop production. Simple radiation and water limited models. ... Nitrogen metabolism, amino acid biosynthesis and catabolism. Biosynthesis of neurotransmitters, pigments, hormones and ...
Glycolysis, citric acid cycle and electron transport. Glycogen metabolism, pentose-phosphate pathway, gluconeogenesis and ... Perspectives on the flow of information from nucleic acids to proteins, the structure and functions of nucleic acids and ... Nucleic acid structure as observed in fibres and crystals as well as global DNA and RNA analyses (methods and bioinformatic ... The urea cycle, nitrogen excretion. Practical training in scientific writing skills: evaluation of a scientific report. ...
NADH remains high and NAD+ is too low for citric acid cycle operation31. We suggest that the resulting high [NADH]/[NAD+] ratio ... pyruvic acid formulation at 1.5 K. The formulations included 11.1 to 14.0 mM OX063 radical. The amount of [1-13C]pyruvic acid ... 5 mM ascorbic acid, 2 mM thiourea, and 3 mM pyruvic acid in double distilled water. ... 5 mM ascorbic acid, 2 mM thiourea, and 3 mM pyruvic acid in double distilled water. ...
Citric Acid Cycle. Definition. *a cyclic series of metabolic reactions that completely oxidize acetyl units to carbon dioxide ... Also known as the tricarboxylic acid cycle (after citrate) or the Krebs cycle, after Hans Krebs, who elucidated the cyclic ... an essential amino acid. *a hydrophobic amino acid that is similar to alanine but contains a phenyl ring in place of one of the ... one of the non-essentialamino acids. *a hydrophobic amino acid that has an alipathic side chain bonded to both the alpha carbon ...
altered citric acid cycle pathway Symbol. Object Name. Evidence. Notes. Source. PubMed Reference(s). RGD Reference(s). Position ...
... tricarboxylic acid cycle (TCA), and electron transport chain (ETC). Taken together, our findings highlight a novel role for ... our findings highlight a novel role for Rab27b in maintaining fatty acid oxidation in C-MSCs. ... Rab27b in maintaining fatty acid oxidation in C-MSCs. ... tricarboxylic acid cycle (TCA), and electron transport chain ( ... Akram, M. (2014). Citric acid cycle and role of its intermediates in metabolism. Cell Biochem. Biophys. 68, 475-478. doi: ...
... from pyruvic acid to citric acid, a continuous series encompassing a large part of the extant Krebs cycle). These data shape a ... of aminoacids and of eight carboxylic acids (forming, ... citric acid 11, palmitic acid 12, stearic acid 13, glycine 23, ... from pyruvic acid to citric acid, a continuous series encompassing a large part of the extant Krebs cycle). These data shape a ... Eschenmoser, A. On a Hypothetical Generational Relationship between HCN and Constituents of the Reductive Citric Acid Cycle. ...
MeSH Terms: Adenosine Triphosphate/metabolism; Carbon-13 Magnetic Resonance Spectroscopy; Cell Line, Tumor; Citric Acid Cycle; ... De novo fatty acid production was ∼ 6% of the tricarboxylic acid cycle flux. The oxidative pentose phosphate pathway flux was ... Even though the rate of glutamine uptake was ∼ 50% of the tricarboxylic acid cycle flux, the rate of ATP production from ...
Organization of citric-acid cycle enzymes into a multienzyme cluster. FEBS Lett 201(2):267-2703086126. Crossref, Medline, ...
"Protometabolic Analogs of the Modern Citric Acid Cycle" - Greg Springsteen, Ph.D. - Furman University ... In the Krishnamurthy lab, she synthesized modified ribulose sugars to study ribulose nucleic acids as potential prebiotic ... "Cycles and Systems: Ratcheting Toward Life" - Martha Grover, Ph.D. - Georgia Tech ...
Both of these metabolites are normal constituents of the citric acid cycle and are further metabolized to ... Propylene glycol is metabolized to compounds that are normal constituents of the citric acid cycle. ...
3-propanetricarboxylic acid, HO2CCH2C(OH)(CO2H)CH2CO2H, an organic carboxylic acid [1] containing three carboxyl groups [2]; it ... The citric acid cycle is also known as the Krebs cycle, after the German-British biochemist Sir Hans Adolf Krebs (1900-1981), ... The structure of citric acid is shown below. The COOH group is a carboxylic acid group, so citric acid is a tricarboxylic acid ... citric acid (sit-rik) n. an organic acid found naturally in citrus fruits. Citric acid is formed in the first stage of the ...
  • The NADH generated by the citric acid cycle is fed into the oxidative phosphorylation (electron transport) pathway. (wikipedia.org)
  • The NADH and FADH2 generated by the citric acid cycle are, in turn, used by the oxidative phosphorylation pathway to generate energy-rich ATP. (wikipedia.org)
  • Some texts refer to it as the Krebs cycle or the tricarboxylic acid cycle, and its role is to produce NADH and FADH2 for oxidative phosphorylation. (medistudents.com)
  • Pyruvate enters the mitochondria with the substrate being ultimately metabolized to CO 2 and H 2 O by the citric acid cycle which results in ATP formation by oxidative phosphorylation. (pharmacology2000.com)
  • The SDH enzyme links two important cellular pathways called the citric acid cycle (or Krebs cycle) and oxidative phosphorylation. (medlineplus.gov)
  • proton-linked monocarboxylate transporter 1 complex catalyses the first reaction of the Citric Acid Cycle, the oxidation of lactate to pyruvate, and thus secures the provision of pyruvic acid. (nih.gov)
  • We report the one-pot synthesis of all the natural nucleobases, of aminoacids and of eight carboxylic acids (forming, from pyruvic acid to citric acid, a continuous series encompassing a large part of the extant Krebs cycle). (nature.com)
  • Glycolysis is the breakdown of Carbohydrates (in the form of Glucose or Glycogen) into Pyruvic acid and two ATP molecules. (teachpe.com)
  • Converting Carbohydrates into Pyruvic acid uses a total of 10 chemical reactions. (teachpe.com)
  • The Pyruvic acid produced during Glycolysis enters the mitochondria and immediately converts to Acetyl Coenzyme A. Mitochondria are the cell's powerhouses that produce energy. (teachpe.com)
  • The molecules of glucose get converted into pyruvic acid which is oxidized to carbon dioxide and water, leaving two carbon molecules, known as acetyl-CoA. (byjus.com)
  • For each pyruvate molecule (from glycolysis), the overall yield of energy-containing compounds from the citric acid cycle is three NADH, one FADH2, and one GTP. (wikipedia.org)
  • One of the primary sources of acetyl-CoA is from the breakdown of sugars by glycolysis which yield pyruvate that in turn is decarboxylated by the pyruvate dehydrogenase complex generating acetyl-CoA according to the following reaction scheme: CH3C(=O)C(=O)O−pyruvate + HSCoA + NAD+ → CH3C(=O)SCoAacetyl-CoA + NADH + CO2 The product of this reaction, acetyl-CoA, is the starting point for the citric acid cycle. (wikipedia.org)
  • One molecule of glucose is degraded to two molecules of lactic acid by the process of glycolysis. (nih.gov)
  • Assume all glucose is metabolized through glycolysis and its product pyruvate enters into the citric acid cycle. (solutionsfolks.com)
  • Below is a schematic outline of the cycle: The citric acid cycle begins with the transfer of a two-carbon acetyl group from acetyl-CoA to the four-carbon acceptor compound (oxaloacetate) to form a six-carbon compound (citrate). (wikipedia.org)
  • The carbons donated by acetyl-CoA become part of the oxaloacetate carbon backbone after the first turn of the citric acid cycle. (wikipedia.org)
  • The citric acid cycle plays a critical part in cellular aerobic respiration, converting citric acid to oxaloacetate over a series of 8 steps. (medistudents.com)
  • C) Oxaloacetate is used as a substrate but is not consumed in the cycle. (easynotecards.com)
  • Acetyl-CoA labeled with 14C in both of its acetate carbon atoms is incubated with unlabeled oxaloacetate and a crude tissue preparation capable of carrying out the reactions of the citric acid cycle. (easynotecards.com)
  • After a single pass through the citric acid cycle back to oxaloacetate, what fraction of the original radioactivity will be found in the oxaloacetate? (easynotecards.com)
  • The citric acid cycle is a metabolic pathway that connects carbohydrate, fat, and protein metabolism. (wikipedia.org)
  • Here we show that stroma-associated pancreatic stellate cells (PSCs) are critical for PDAC metabolism through the secretion of non-essential amino acids (NEAA). (nih.gov)
  • Changes in fatty acid metabolism can lead to a variety of CVDs. (frontiersin.org)
  • In this study, we first evaluated the role of Rab27b in the metabolism of adult C-MSCs and found that knockdown of Rab27b inhibits mitochondrial fatty acid β-oxidation, TCA, and ETC by decreasing the expression of related genes, resulting in mitochondrial respiratory depression in C-MSC. (frontiersin.org)
  • Citric acid plays an important role in metabolism, the set of chemical reactions that occur when cells break down fats, carbohydrates, and other compounds to produce energy and compounds needed to build new cells and tissues. (encyclopedia.com)
  • Pyruvate metabolism through the citric acid cycle results in an increase in intracellular glutamate. (pharmacology2000.com)
  • 18. The tricarboxylic acid cycle in L₃ Teladorsagia circumcincta: metabolism of acetyl CoA to succinyl CoA. (nih.gov)
  • Lipid metabolism: fatty acid biosynthesis and degradation, and ketone bodies. (uwaterloo.ca)
  • Amino acid metabolism: selected degradation pathways that are of medical significance, and the urea cycle. (uwaterloo.ca)
  • The Krebs cycle is part of aerobic metabolism. (teachpe.com)
  • Pathway analysis also identified changes in metabolic pathways unique for different tissues, including changes in the citric acid cycle (jejunum), beta-alanine metabolism (skeletal muscle), and purine metabolism (liver). (rti.org)
  • Furthermore, calcium can activate two of the rate-limiting enzymes of the citric acid cycle: isocitrate dehydrogenase and α-ketoglutarate dehydrogenase. (medistudents.com)
  • The citric acid cycle -also known as the Krebs cycle, Szent-Györgyi-Krebs cycle or the TCA cycle (tricarboxylic acid cycle)-is a series of chemical reactions to release stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins. (wikipedia.org)
  • The name of this metabolic pathway is derived from the citric acid (a tricarboxylic acid, often called citrate, as the ionized form predominates at biological pH) that is consumed and then regenerated by this sequence of reactions to complete the cycle. (wikipedia.org)
  • The citric acid cycle (CAC) - also known as the tricarboxylic acid (TCA) cycle or the Krebs cycle - is a series of chemical reactions used by all aerobic organisms to release stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins into carbon dioxide and chemical energy in the mitochondria. (solutionsfolks.com)
  • Specifically, we uncover a previously undescribed role for alanine, which outcompetes glucose and glutamine-derived carbon in PDAC to fuel the tricarboxylic acid (TCA) cycle, and thus NEAA and lipid biosynthesis. (nih.gov)
  • Furthermore, knockdown of Rab27b reduced H3k4me3 expression in C-MSC and selectively decreased the expression of the essential genes involved in β-oxidation, tricarboxylic acid cycle (TCA), and electron transport chain (ETC). Taken together, our findings highlight a novel role for Rab27b in maintaining fatty acid oxidation in C-MSCs. (frontiersin.org)
  • Even though the rate of glutamine uptake was ∼ 50% of the tricarboxylic acid cycle flux, the rate of ATP production from glutamine was essentially zero (no glutaminolysis). (nih.gov)
  • De novo fatty acid production was ∼ 6% of the tricarboxylic acid cycle flux. (nih.gov)
  • 12. Enzymes of the tricarboxylic acid cycle in Ancylostoma ceylanicum and Nippostrongylus brasiliensis. (nih.gov)
  • 15. Global transcription analysis of Krebs tricarboxylic acid cycle mutants reveals an alternating pattern of gene expression and effects on hypoxic and oxidative genes. (nih.gov)
  • The Krebs cycle (Citric acid or Tricarboxylic acid cycle) is the second phase of aerobic respiration. (teachpe.com)
  • This is also known as the tricarboxylic acid cycle or Kreb's cycle. (byjus.com)
  • In prokaryotic cells, such as bacteria, which lack mitochondria, the citric acid cycle reaction sequence is performed in the cytosol with the proton gradient for ATP production being across the cell's surface (plasma membrane) rather than the inner membrane of the mitochondrion. (wikipedia.org)
  • Pyruvate enters the inner matrix of mitochondria and undergoes oxidation in the Kreb's cycle. (byjus.com)
  • Although this is the main enzyme involved in regulating the cycle, citrate synthase and α-ketoglutarate dehydrogenase have also been found to have important roles in regulation, though the details of these are not required for the MCAT. (medistudents.com)
  • As part of the citric acid cycle, the SDH enzyme converts a compound called succinate to another compound called fumarate. (medlineplus.gov)
  • This enzyme participates in an important series of reactions known as the citric acid cycle or Krebs cycle, which allows cells to use oxygen and generate energy. (nih.gov)
  • By 1960 Stanford Moore and William Stein had determined fully the sequence of the 124 amino acids in ribonuclease, the first enzyme to be so analyzed. (nih.gov)
  • Common oxidative pathways: citric acid cycle and the respiratory chain. (uwaterloo.ca)
  • Tissue-culture studies suggest an interference with metabolic pathways of amino acids leading from glutamic acid to the citric acid cycle and to urea. (nih.gov)
  • Acetyl-CoA may also be obtained from the oxidation of fatty acids. (wikipedia.org)
  • In 1937, Sir H. A Krebs first published the Citric Acid Cycle, a unidirectional cycle with carboxylic acids. (nih.gov)
  • The reactions of the cycle are carried out by eight enzymes that completely oxidize acetate (a two carbon molecule), in the form of acetyl-CoA, into two molecules each of carbon dioxide and water. (wikipedia.org)
  • There is 1 molecule of FADH₂ produced per rotation of the cycle. (medistudents.com)
  • It frequently occurs as the monohydrate, with a single molecule of water associated with each citric acid molecule. (encyclopedia.com)
  • Endonuclease -- Any of a group of enzymes catalyzing the hydrolysis of bonds between nucleic acids in the interior of a DNA or RNA molecule. (nih.gov)
  • Other studies indicate that vinblastine sulfate has an effect on cell-energy production required for mitosis and interferes with nucleic acid synthesis. (nih.gov)
  • BiGG Models: A platform for integrating, standardizing, and sharing genome-scale models (2016) Nucleic Acids Research 44(D1):D515-D522. (ucsd.edu)
  • The reverse synthetic reaction, gluconeogenesis is the conversion of lactic acid to glucose. (nih.gov)
  • Through catabolism of sugars, fats, and proteins, the two-carbon organic product acetyl-CoA is produced which enters the citric acid cycle. (wikipedia.org)
  • The resulting 2-carbon acetyl CoA enters the citric acid cycle, while NADH is used later in aerobic respiration for the electron transport chain. (medistudents.com)
  • Several of the components and reactions of the citric acid cycle were established in the 1930s by the research of Albert Szent-Györgyi, who received the Nobel Prize in Physiology or Medicine in 1937 specifically for his discoveries pertaining to fumaric acid, a component of the cycle. (wikipedia.org)
  • The citric acid cycle is also known as the Krebs cycle , after the German-British biochemist Sir Hans Adolf Krebs (1900-1981), who discovered the series of reactions in 1937. (encyclopedia.com)
  • The Krebs cycle is used by organisms that respire (as opposed to organisms that ferment) to generate energy, either by anaerobic respiration or aerobic respiration. (wikipedia.org)
  • That's why citric acid cycle, um, and on aerobic respiration is so important when you think about it. (pearson.com)
  • If Oxygen is present then the cell uses aerobic respiration (with oxygen) and then continues on to Krebs Cycle. (teachpe.com)
  • In 1917, the American chemist James Currie (dates not available) made another important breakthrough in the synthesis of citric acid. (encyclopedia.com)
  • The previously mentioned isocitrate dehydrogenase is the rate limiting step of the citric acid cycle. (medistudents.com)
  • The reactions of the cycle also convert three equivalents of nicotinamide adenine dinucleotide (NAD+) into three equivalents of reduced NAD+ (NADH), one equivalent of flavin adenine dinucleotide (FAD) into one equivalent of FADH2, and one equivalent each of guanosine diphosphate (GDP) and inorganic phosphate (Pi) into one equivalent of guanosine triphosphate (GTP). (wikipedia.org)
  • The cycle consumes acetate (in the form of acetyl-CoA) and water, reduces NAD+ to NADH, releasing carbon dioxide. (wikipedia.org)
  • Loss of the acetyl-CoA-donated carbons as CO2 requires several turns of the citric acid cycle. (wikipedia.org)
  • Reversal of the antitumor effect of vinblastine sulfate by glutamic acid or tryptophan has been observed. (nih.gov)
  • In addition, glutamic acid and aspartic acid have protected mice from lethal doses of vinblastine sulfate. (nih.gov)
  • catabolism of pyrimidines produces citric acid cycle intermediates. (msdmanuals.com)
  • The citric acid cycle (or the Krebs cycle) is an essential subject to revise as part of your MCAT preparation. (medistudents.com)
  • 10. Accumulation of Krebs cycle intermediates and over-expression of HIF1alpha in tumours which result from germline FH and SDH mutations. (nih.gov)
  • 13. Genetic alterations in Krebs cycle and its impact on cancer pathogenesis. (nih.gov)
  • One such important chemical pathway is the circular assembly line known as the Krebs cycle. (visionlearning.com)
  • The main biochemical pathway where the breakdown of biological fuels comes together is called the Krebs cycle. (visionlearning.com)
  • Define the Krebs cycle. (byjus.com)
  • For example, GlnZ represses the activity of glnP and sucA RNAs, which respectively contribute to glutamine transport and the cell's citric acid cycle. (nih.gov)
  • Which compound is NOT an intermediate of the citric acid cycle? (easynotecards.com)
  • In fact, the series of reactions by which carbohydrates are converted to energy is generally known as the citric acid cycle because of the fundamental role played by the compound in those reactions. (encyclopedia.com)
  • The first person to isolate the compound as a pure substance was the Swedish chemist Karl Wilhelm Scheele (1742-1786), who obtained citric acid from the juice of lemons. (encyclopedia.com)
  • After Currie joined the pharmaceutical company Pfizerin 1917, he developed a process called SUCIAC-sugar under conversion into citric acid-by which the compound could be made in mass quantities. (encyclopedia.com)
  • This combines with Oxaloacetic acid to form a 6-carbon compound, known as Citric acid. (teachpe.com)
  • These actions both increase pyruvate dehydrogenase activity, therefore stimulating the cycle as a whole. (medistudents.com)
  • A) All enzymes of the cycle are located in the cytoplasm, except succinate dehydrogenase, which is bound to the inner mitochondrial membrane. (easynotecards.com)
  • 11. The TCA cycle and tumorigenesis: the examples of fumarate hydratase and succinate dehydrogenase. (nih.gov)
  • These intermediates are then oxidized by a common mechanism that comprises the citric acid cycle and the respiratory chain. (uwaterloo.ca)
  • 14. The functional roles of TCA cycle metabolites in cancer. (nih.gov)
  • The original concept of the Citric Acid Cycle from Krebs' 1953 Nobel Prize lecture illustrates the unidirectional degradation of lactic acid to water, carbon dioxide and hydrogen. (nih.gov)
  • The polyunsaturated fatty acids (PUFAs) are lipid derivatives of omega-3 (docosahexaenoic acid, DHA , and eicosapentaenoic acid, EPA ) or of omega-6 (arachidonic acid, ARA ) are synthesized from membrane phospholipids and used as a precursor for endocannabinoids (ECs) mediate significant effects in the fine-tuning adjustment of body homeostasis. (wikipedia.org)
  • Glucagon is a 29 amino acid linear polypeptide produced by pancreatic islet A cells and by upper G.I. tract cells. (pharmacology2000.com)
  • Preproglucagon in L cells is processed mainly to glicentin which consists of glucagon with amino acid residue extensions at either end and to glucagon-like polypeptides 1 and 2 (GLP-1 and GLP-2). (pharmacology2000.com)
  • Think of amino acid chains. (blogspot.com)
  • So this reaction is also one of those easily reversible ones it produces an eight th and it takes mallet and turns it into ox alot acetate, and we are ready to start the cycle again. (pearson.com)
  • The obtained results confirm the hypothesis that the binding of gadopentetate to citric acid dendrimer produces a new, biodegradable, stable, and strong version of the old contrast media. (hindawi.com)
  • 3. The existence of a nonclassical TCA cycle in the nucleus that wires the metabolic-epigenetic circuitry. (nih.gov)
  • Aspartic acid was relatively ineffective in reversing the antitumor effect. (nih.gov)
  • The principal product of the citric acid cycle is NADH, which is essential for the function of the electron transport chain. (medistudents.com)
  • A further regulator of both the link reaction and the citric acid cycle is calcium. (medistudents.com)
  • The citric acid produced in this reaction is purified by crystallization. (encyclopedia.com)
  • Made up of a complex of amino-acids, enzymes are part of every chemical reaction in living things. (nih.gov)
  • Photosynthesis light reaction calvin cycle electron transport 3d animation Are the most beautiful, funny and lovely cartoon images Many young people like and look for cute pictures with many different emotions. (lestwinsonline.com)
  • In addition, we modify Krebs' original concept by feeding the cycle with oxaloacetic acid. (nih.gov)
  • The process is termed a cycle because the starting product Oxaloacetic acid is also the end product. (teachpe.com)
  • The citric acid cycle is a part of cellular respiration, the process where your body harvests energy from the food you eat, CAC is chemical reactions used by all aerobic organisms to release stored. (online-sciences.com)
  • Stoichiometry of chemical reactions, quantum mechanical description of atoms, the elements and periodic table, chemical bonding, real and ideal gases, thermochemistry, introduction to thermodynamics and equilibrium, acid-base and solubility equilibria, introduction to oxidation-reduction reactions. (blogspot.com)
  • How Physical Chemistry and Thermodynamics can be used to understand equilibrium balances in nature, with applications to simple organic reactions, acid-base chemistry, solubility and materials, molecular kinetics, and electrochemistry. (blogspot.com)
  • Citric acid also acts as an antioxidant, a substance that rid the body of molecules called free radicals that can damage healthy cells, promote cancer, and bring about ageing. (encyclopedia.com)
  • Two ATP molecules are produced in each phase of the citric acid cycle and it takes place within the mitochondrial matrix of a cell. (byjus.com)
  • An example of this is in the control of bile acids in the liver . (wikipedia.org)
  • 1. Mitochondrial dysfunctions in cancer: genetic defects and oncogenic signaling impinging on TCA cycle activity. (nih.gov)
  • 6. Biochemical assays for mitochondrial activity: assays of TCA cycle enzymes and PDHc. (nih.gov)
  • The electrons generated in Kreb's cycle move across the mitochondrial matrix. (byjus.com)
  • In mammals, what process does NOT occur during the citric acid cycle? (easynotecards.com)