Citric Acid Cycle: 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.Citric Acid: 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.CitratesMalatesIsocitrate Dehydrogenase: 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 18.104.22.168.) EC 22.214.171.124.Oxaloacetates: 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.Fumarate Hydratase: 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 126.96.36.199.Aconitate Hydratase: 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 188.8.131.52.Ketoglutaric Acids: A family of compounds containing an oxo group with the general structure of 1,5-pentanedioic acid. (From Lehninger, Principles of Biochemistry, 1982, p442)Pyruvic Acid: 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)Ketoglutarate Dehydrogenase ComplexOxaloacetic Acid: 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.Malate Dehydrogenase: An enzyme that catalyzes the conversion of (S)-malate and NAD+ to oxaloacetate and NADH. EC 184.108.40.206.Citrate (si)-Synthase: 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 220.127.116.11.Acetyl Coenzyme A: 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.Succinic Acid: 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)Carbon Isotopes: 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.PyruvatesSuccinate Dehydrogenase: 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.Acetates: Derivatives of ACETIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxymethane structure.GlyoxylatesSuccinate-CoA Ligases: 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 18.104.22.168) or GTP to GDP (EC 22.214.171.124) and orthophosphate. Itaconate can act instead of succinate and ITP instead of GTP.EC 6.2.1.-.Fluoroacetates: 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)Cell Cycle: 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.Fumarates: Compounds based on fumaric acid.Succinates: 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.Glycolysis: 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.Glutamates: 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.Gluconeogenesis: Biosynthesis of GLUCOSE from nonhexose or non-carbohydrate precursors, such as LACTATE; PYRUVATE; ALANINE; and GLYCEROL.Ketone Bodies: 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.Heptanoates: Salts and esters of the 7-carbon saturated monocarboxylic acid heptanoic acid.Malate Synthase: 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 126.96.36.199.Pyruvate Carboxylase: 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 188.8.131.52.Dicarboxylic Acid Transporters: A family of organic anion transporters that specifically transport DICARBOXYLIC ACIDS such as alpha-ketoglutaric acid across cellular membranes.Glucose: 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.Carbon Dioxide: A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.GlutaratesMitochondria: 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)Glutamine: 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.Acetoacetates: Salts and derivatives of acetoacetic acid.Oxo-Acid-Lyases: Enzymes that catalyze the cleavage of a carbon-carbon bond of a 3-hydroxy acid. (Dorland, 28th ed) EC 4.1.3.Oxygen Consumption: 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 AcidsEnergy Metabolism: The chemical reactions involved in the production and utilization of various forms of energy in cells.Acetic Acid: 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)Magnetic Resonance Spectroscopy: 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).Oxidation-Reduction: 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).Lactic Acid: A normal intermediate in the fermentation (oxidation, metabolism) of sugar. The concentrated form is used internally to prevent gastrointestinal fermentation. (From Stedman, 26th ed)Hydro-Lyases: Enzymes that catalyze the breakage of a carbon-oxygen bond leading to unsaturated products via the removal of water. EC 4.2.1.Carbon: 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 AGlutamic Acid: A non-essential amino acid naturally occurring in the L-form. Glutamic acid is the most common excitatory neurotransmitter in the CENTRAL NERVOUS SYSTEM.Aspartic Acid: 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.Propionates: Derivatives of propionic acid. Included under this heading are a broad variety of acid forms, salts, esters, and amides that contain the carboxyethane structure.Perfusion: Treatment process involving the injection of fluid into an organ or tissue.Models, Biological: 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.Aspergillus niger: An imperfect fungus causing smut or black mold of several fruits, vegetables, etc.Tricarboxylic Acids: 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)Kinetics: The rate dynamics in chemical or physical systems.Myocardium: 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.NAD: 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)Menstrual Cycle: 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.Cough: 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.Taste: The ability to detect chemicals through gustatory receptors in the mouth, including those on the TONGUE; the PALATE; the PHARYNX; and the EPIGLOTTIS.Pyruvate Dehydrogenase Complex: 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)Lactates: Salts or esters of LACTIC ACID containing the general formula CH3CHOHCOOR.Gas Chromatography-Mass Spectrometry: A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.Mitochondria, Heart: The mitochondria of the myocardium.Carboxylic Acids: 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.Culture Media: 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.Molecular Sequence Data: 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.Oxidoreductases: 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)Swine: 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, Liver: 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)Antitussive Agents: Agents that suppress cough. They act centrally on the medullary cough center. EXPECTORANTS, also used in the treatment of cough, act locally.Fatty Acids: 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)Rats, Sprague-Dawley: 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.Adenosine Triphosphate: 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.Bacillus subtilis: A species of gram-positive bacteria that is a common soil and water saprophyte.Mutation: 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.Taste Threshold: The minimum concentration at which taste sensitivity to a particular substance or food can be perceived.Amino Acids: 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.Iron-Sulfur 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.Cell Cycle Proteins: 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.IsocitratesOsmeriformes: An order of fish including smelts, galaxiids, and salamanderfish.Aconitic AcidRoot Canal Irrigants: 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.Metacercariae: Encysted cercaria which house the intermediate stages of trematode parasites in tissues of an intermediate host.Quinine: 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.Rats, Inbred Strains: 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.Gene Expression Regulation, Bacterial: Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.Smear Layer: 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.Acetobacter: 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.Caproates: 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.Estrous Cycle: 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).Escherichia coli: 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.Heart: The hollow, muscular organ that maintains the circulation of the blood.Taste Perception: 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.Metabolome: The dynamic collection of metabolites which represent a cell's or organism's net metabolic response to current conditions.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Stars, Celestial: Large bodies consisting of self-luminous gas held together by their own gravity. (From McGraw Hill Dictionary of Scientific and Technical Terms, 6th ed)Sucrose: 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.TartratesTongue: 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.Pentose Phosphate Pathway: 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, Messenger: 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.Hydrogen-Ion Concentration: 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)
Citric acid cycle (TCA cycle) | Design elements - TCA cycle | Biology Symbols | Citric Acid Cycle
Citric acid cycle (tricarboxylic acid cycle, TCA cycle, Krebs cycle) is a series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetate derived from carbohydrates, fats and proteins into carbon dioxide and chemical energy in the form of adenosine triphosphate (ATP). [Citric acid cycle. Wikipedia] |br|This biochemical diagram example shows metabolic pathways map of citric acid cycle reactions. |br|This sample was redesigned from the Wikimedia Commons file: TCA cycle.svg. [commons.wikimedia.org/wiki/File:TCA_cycle.svg] |br|This image is licensed under the Creative Commons Attribution 3.0 Unported license. [creativecommons.org/licenses/by/3.0/deed.en] |br|The metabolic pathway map example Citric acid cycle (TCA cycle) was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Biology solution from the Science and Education area of ConceptDraw Solution Park. Citric Acid Cycle
The glyxoylate shunt consists of two enzymes, isocitrate lyase and malate synthase. Its function is generally anaplerotic, meaning that it replenishes TCA cycle intermediates. Isocitrate (one intermediate) becomes succinate (one intermediate) plus glyoxylate. Glyoxylate plus an acetyl group from acetyl-CoA becomes malate, a second intermediate, for a gain of one. Acetyl groups, such as from fatty acid metabolism, by means of this pathway, can provide TCA cycle intermediates for use in amino acid biosynthesis and other biosynthetic pathways ...
Citric acid cycle - Wikipedia
Several catabolic pathways converge on the citric acid cycle. Most of these reactions add intermediates to the citric acid cycle, and are therefore known as anaplerotic reactions, from the Greek meaning to "fill up". These increase the amount of acetyl CoA that the cycle is able to carry, increasing the mitochondrions capability to carry out respiration if this is otherwise a limiting factor. Processes that remove intermediates from the cycle are termed "cataplerotic" reactions. In this section and in the next, the citric acid cycle intermediates are indicated in italics to distinguish them from other substrates and end-products. Pyruvate molecules produced by glycolysis are actively transported across the inner mitochondrial membrane, and into the matrix. Here they can be oxidized and combined with coenzyme A to form CO2, acetyl-CoA, and NADH, as in the normal cycle.. However, it is also possible for pyruvate to be carboxylated by pyruvate carboxylase to form oxaloacetate. This latter ...
"Tricarboxylic acid cycle intermediates in muscular dystrophic mice (st" by R G. Montalbo and J J. Kabara
Citric Acid Cycle
Lecture: 4 Biochemistry Anwar J Almzaiel. Citric acid cycle - PDF
The growth and survival of cancer cells is dependent on extracellular glutamine, which is frequently depleted in solid tumors, resulting in the induction of apoptosis. Glutamine has been suggested to maintain cancer cell viability by replenishing intermediates for the tricarboxylic acid (TCA) cycle and supporting de novo biosynthesis of nucleotides and nonessential amino acids. Zhang and colleagues sought to characterize the mechanism by which glutamine withdrawal induces apoptosis using a high-throughput RNAi-based screen to identify genes whose loss protected MYC-transformed cells from apoptosis following glutamine withdrawal. Intriguingly, depletion of the TCA cycle enzyme citrate synthase (CS) protected cancer cells from glutamine withdrawal-induced cell death. In the absence of glutamine, knockdown of CS resulted in diminished glycolytic flux through the TCA cycle and redirection of the TCA cycle intermediate oxaloacetate to the synthesis of the nonessential amino acids aspartate and ...
citric acid cycle steps simplified formula|Wholesale|Supplier|China TOP
Sir Krebs outlined the steps of the cycle in 1937. For this reason, it may be called the Krebs cycle. Its also known as the citric acid cycle, for the molecule that is consumed and then regenerated. Another name for citric acid is tricarboxylic acid, so the set of reactions is sometimes called the tricarboxylic acid cycle or TCA cycle.. ...
Koi, Goldfish & Pond Health Nitrite - By Product of Cycle Metabolism of Ammonia by Beneficial Nitrogen Reducing Bacteria in the...
Influence of Threonine Metabolism on S-Adenosylmethionine and Histone Methylation | Science
To test this pathway, we traced the metabolic fate of [U-14C]Thr in mESCs with high-performance liquid chromatography (HPLC). 14C was incorporated into Gly and Glu, indicating that Thr was used to synthesize these amino acids (Fig. 2B). In contrast, MEFs incubated with [U-14C]Thr did not exhibit Thr catabolism (fig. S2A). We also traced the fate of [U-13C]Thr in mESCs with LC-MS/MS metabolomics (fig. S2, B to F, and table S1). mESCs used Thr to synthesize acetyl-CoA-derived tricarboxylic acid (TCA) cycle intermediates (Fig. 2, C and D). At steady state, [U-13C]Thr contributed ~20% of the citrate via acetyl-CoA, whereas [U-13C]glucose contributed ~35% via acetyl-CoA (+2 isotopomer). Thus, Thr contributes significantly to the acetyl-CoA pool in mESCs (Fig. 2D). [U-13C]Thr-derived Gly also donated its 13C-methyl group to ultimately generate 5-methyltetrahydrofolate (5mTHF) and SAM (+1 isotopomer), whereas [U-13C]Ser-derived Gly contributed little to the synthesis of these metabolites (Fig. 2, C and ...
Citric acid cycles Synonyms, Citric acid cycles Antonyms | Thesaurus.com
JCI - Mitochondrial role in the neonatal predisposition to developing nonalcoholic fatty liver disease
Based on nonhuman primate and limited human data, offspring exposed to overnutrition in utero have increased hepatic lipid storage and de novo lipogenesis, coupled with incomplete β-oxidation and diminished electron transport chain (ETC) activity, leading to accumulation of long-chain acylcarnitines (LCACs) and diminished ATP production. Anaplerosis through branched-chain amino acid (BCAA) catabolism compensates for limitations in TCA cycle intermediates. This fuel overload and excess in lipid result in production of ROS. Damage is mitigated by glutathione (GSH) and upregulation of SIRT1 (SRT). Hepatic apoptosis is minimal (but existing). As time progresses and damage, inflammation, and lipid accumulation worsen, mitochondria develop structural abnormalities and diminish in content and activity. This is exacerbated by diet and the microbiome. β-Oxidative function and ETC activity worsen. Intramitochondrial lipid and acylcarnitine accumulation leads to increased ROS and reactive nitrogen ...
Mitochondria and effector functions of human CD8* T cells - edoc
How mitochondrial differences contribute to early effector response in memory CD8+ T cells is still elusive. In manuscript 2, we studied the impact of glucose oxidation in mitochondria on early effector functions in both naïve and memory CD8+ T cells. Metabolomic and glucose tracing experiments assessing metabolic intermediates in both subsets revealed that glycolysis and TCA cycle intermediates were elevated in activated memory CD8+ T cells upon activation. Moreover, we demonstrated that mitochondrial respiration was increased early after activation in memory CD8+ T cells. Blocking mitochondrial respiration diminished early-recall response in memory CD8+ T cells. This suggests that both glycolysis and glucose flux into the TCA are important for rapid IFN-γ secretion. Additionally, we also demonstrated that key components of the mTORC2-Akt axis are present in the mitochondria associated membrane of the endoplasmic reticulum in CD8+ T cells, suggesting a close association between mTORC2-Akt ...
Metabolic pathways and cancer growth--2008 review
The model shows some of the prominent aspects of metabolism in proliferating cells, including glycolysis; lactate production; the use of TCA cycle intermediates as macromolecular precursors; and the biosynthesis of proteins, nucleotides, and lipids. The PI3K/Akt/mTOR pathway, HIF-1α, and Myc participate in various facets of this metabolic phenotype. The binding of a growth factor (GF) to its surface receptor brings about activation of PI3K and the serine/threonine kinases Akt and mTOR (top left). Constitutive activation of the pathway can occur in tumors due to mutation of the tumor suppressors PTEN, TSC1, and TSC2, or by other mechanisms (see text). Metabolic effects of the PI3K/Akt/mTOR pathway include enhanced uptake of glucose and essential amino acids and protein translation. The transcription factor HIF-1α (bottom) is involved in determining the manner in which cells utilize glucose carbon. Translation of HIF-1α is enhanced during growth-factor stimulation of the PI3K/Akt/mTOR pathway. ...
Krebs Cycle Hd Image
Citric acid cycle (tricarboxylic acid cycle, TCA cycle, Krebs cycle) is a series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetate derived from carbohydrates, fats and proteins into carbon dioxide and chemical energy in the form of adenosine triphosphate (ATP). [Citric acid cycle. Wikipedia] |br|This biochemical diagram example shows metabolic pathways map of citric acid cycle reactions. |br|This sample was redesigned from the Wikimedia Commons file: TCA cycle.svg. [commons.wikimedia.org/wiki/File:TCA_cycle.svg] |br|This image is licensed under the Creative Commons Attribution 3.0 Unported license. [creativecommons.org/licenses/by/3.0/deed.en] |br|The metabolic pathway map example Citric acid cycle (TCA cycle) was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Biology solution from the Science and Education area of ConceptDraw Solution Park. Krebs Cycle Hd Image
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In the fed state, most fatty acid-derived acylcarnitine species were present at similar levels in wild-type compared to the knockout mice. Notable exceptions included acetylcarnitine (C2) and beta-OH-butyrylcarnitine (C4OH, a strong marker of beta-oxidation and ketone metabolism), both of which were markedly decreased in plasma, liver, and skeletal muscle of PPARalpha -/- mice regardless of feeding status. Succinylcarnitine (C4DC), which arises from the TCA cycle intermediate succinyl-CoA, was reduced in plasma and liver of PPARalpha -/-mice, independent of condition. Skeletal muscle concentrations of this metabolite were also low in PPARalpha -/- compared to wild-type mice, but only in the fasted state ...
TCA Cycle (Mus musculus) - WikiPathways
The citric acid cycle, also known as the tricarboxylic acid cycle (TCA cycle) or the Krebs cycle, (or rarely, the Szent-Gyorgyi-Krebs cycle) is a series of enzyme-catalysed chemical reactions of central importance in all living cells that use oxygen as part of cellular respiration. In eukaryotes, the citric acid cycle occurs in the matrix of the mitochondrion. The components and reactions of the citric acid cycle were established by seminal work from both Albert Szent-Gyorgyi and Hans Krebs. [From Wikipedia ...
Reverse Krebs cycle - Wikipedia
The reverse Krebs cycle (also known as the reverse tricarboxylic acid cycle, the reverse TCA cycle, or the reverse citric acid cycle) is a sequence of chemical reactions that are used by some bacteria to produce carbon compounds from carbon dioxide and water. The reaction is the citric acid cycle run in reverse: Where the Krebs cycle takes complex carbon molecules in the form of sugars and oxidizes them to CO2 and water, the reverse cycle takes CO2 and water to make carbon compounds. This process is used by some bacteria to synthesise carbon compounds, sometimes using hydrogen, sulfide, or thiosulfate as electron donors. In this process, it can be seen as an alternative to the fixation of inorganic carbon in the reductive pentose phosphate cycle which occurs in a wide variety of microbes and higher organisms. The reaction is a possible candidate for prebiotic early-earth conditions and, so, is of interest in the research of the origin of life. It has been found that some non-consecutive ...
Metabolite Profiles During Oral Glucose Challenge
To identify distinct biological pathways of glucose metabolism, we conducted a systematic evaluation of biochemical changes after an oral glucose tolerance test (OGTT) in a community-based population. Metabolic profiling was performed on 377 nondiabetic Framingham Offspring cohort participants (mean age 57 years, 42% women, BMI 30 kg/m2) before and after OGTT. Changes in metabolite levels were evaluated with paired Student t tests, cluster-based analyses, and multivariable linear regression to examine differences associated with insulin resistance. Of 110 metabolites tested, 91 significantly changed with OGTT (P ≤ 0.0005 for all). Amino acids, β-hydroxybutyrate, and tricarboxylic acid cycle intermediates decreased after OGTT, and glycolysis products increased, consistent with physiological insulin actions. Other pathways affected by OGTT included decreases in serotonin derivatives, urea cycle metabolites, and B vitamins. We also observed an increase in conjugated, and a decrease in ...
Citric Acid Cycle and Oxidative Phosphorylation | Open Textbooks for Hong Kong
The citric acid cycle is a series of chemical reactions that removes high-energy electrons and uses them in the electron transport chain to generate ATP. One molecule of ATP (or an equivalent) is produced per each turn of the cycle. The electron transport chain is the portion of aerobic respiration that uses free oxygen as the final electron acceptor for electrons removed from the intermediate compounds in glucose catabolism. The electrons are passed through a series of chemical reactions, with a small amount of free energy used at three points to transport hydrogen ions across the membrane. This contributes to the gradient used in chemiosmosis. As the electrons are passed from NADH or ...
Videos Archives - Biochemistry Den
Krebs cycle animation and Citric acid cycle : Central metabolic cycle and its Significance Citric acid cycle is also called Krebs Cycle and Tricarboxylic acid cycle. The citric acid cycle is a aerobic universal Acetyl~coA catabolic cycle. It is a central metabolic cycle. The cycle was first elucidated by scientist "Sir Hans Adolf Krebs" (LT, […] ...
Respiration: Types and Significance | Biology EduCare
Citric acid cycle consists of number of reactions which produce NADH and FADH₂ and then they are used by the oxidative phosphorylation pathway to make ATP which then passes through the electron transport system. The citric acid cycle happens in the matrix of the mitochondria of the cell. The oxydation of pyruvic acid takes place through a series of reaction. These reactions produced through a cycle known as tricarboxylic acid cycle. It is also known as TCA cycle. The first product in this cycle is cytric acid hence it is called the citric acid cycle or CAC. ...
Solution - Distinguish Between Glycolysis and Citric Acid Cycle - Glycolysis | shaalaa.com
Citric Acid Cycle - Proteopedia, life in 3D
L18-Mitochondria and Citric Acid Cycle | MindMeister Mind Map
5. Oxidative Phosphorylation - Module 3: Glucose oxidation and energy production | Coursera
Welcome back to my Coursera class, Biochemical Principles of Energy Metabolism. This is final session for week three, final session. Its about Oxidative Phosphorylation. Im just showing you the same slide repeatedly. Step number one of glucose degradation is glycolysis, C6 glucose phosphorylated. Its like energy and investment period and then, the glucose molecules will be split into C3 compound. We extract a little bit of ATP molecules and then pyruvic acid getting into the mitochondrial matrix. Inside of mitochondria matrix, there is citric acid cycle. Throughout this citric acid cycle, the carbon backbones will be fully oxidized and CO2 will be released and we can extract a lot of reduced electron carriers, throughout those oxidation, NAD, reduced NADH or FADH2. This is step number two. So far, in terms of number of ATP molecules, we cannot say glycolysis citric acid cycle are highly efficient energy-generating processes because during the glycolysis, four ATP molecules are produced. In ...
Nitric Oxide Modulates Metabolic Remodeling in Inflammatory Macrophages through TCA Cycle Regulation and Itaconate Accumulation...
Classical activation of macrophages (M(LPS+IFNγ)) elicits the expression of inducible nitric oxide synthase (iNOS), generating large amounts of NO and inhibiting mitochondrial respiration. Upregulation of glycolysis and a disrupted tricarboxylic acid (TCA) cycle underpin this switch to a pro-inflammatory phenotype. We show that the NOS cofactor tetrahydrobiopterin (BH4) modulates IL-1β production and key aspects of metabolic remodeling in activated murine macrophages via NO production. Using two complementary genetic models, we reveal that NO modulates levels of the essential TCA cycle metabolites citrate and succinate, as well as the inflammatory mediator itaconate. Furthermore, NO regulates macrophage respiratory function via changes in the abundance of critical N-module subunits in Complex I. However, NO-deficient cells can still upregulate glycolysis despite changes in the abundance of glycolytic intermediates and proteins involved in glucose metabolism. Our findings reveal a fundamental role for
TCA cycle activity in Saccharomyces cerevisiae is a function of the environmentally determined specific growth and glucose...
Adenosine triphosphate - wikidoc
In the mitochondrion, pyruvate is oxidized by the pyruvate dehydrogenase complex to acetyl CoA, which is fully oxidized to carbon dioxide by the citric acid cycle (also known as the Krebs Cycle). Every "turn" of the citric acid cycle produces two molecules of carbon dioxide, one molecule of the ATP equivalent guanosine triphosphate (GTP) through substrate-level phosphorylation catalyzed by succinyl CoA synthetase, three molecules of the reduced coenzyme NADH, and one molecule of the reduced coenzyme FADH2. Both of these latter molecules are recycled to their oxidized states (NAD+ and FAD, respectively) via the electron transport chain, which generates additional ATP by oxidative phosphorylation. The oxidation of an NADH molecule results in the synthesis of about 3 ATP molecules, and the oxidation of one FADH2 yields about 2 ATP molecules. The majority of cellular ATP is generated by this process. Although the citric acid cycle itself does not involve molecular oxygen, it is an obligately ...
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Philosophical Transactions of the Royal Society B: Biological Sciences
Most animals are able to generate energy using either aerobic or anaerobic metabolic pathways, with glycolytic anaerobic respiration generating approximately 2 ATP molecules and aerobic respiration (citric acid cycle+oxidative phosphorylation) approximately 36.. Although the citric acid cycle does not directly rely on free oxygen, it does not take place under anaerobic conditions. As there is no free oxygen to act as the final electron acceptor, the intermediates all along the oxidative phosphorylation chain remain in a reduced state. As a result, the chain stops functioning, and the build up of the end products means (via Le Chateliers Principle) that the citric acid cycle, too, halts. However, glycolysis can still occur, leading to a build up of pyruvate and a small amount of ATP (two to three molecules).. So much for the basic biochemistry, the broad outline of which is extremely well known. What is less well known, however, is the presence of a variety of anaerobic respiratory pathways in ...
Biochemical Studies on the Effects of Lithium Salts: Excretion of Tricarboxylic Acid-Cycle Intermediary Metabolites, Inhibition...
Glucose catabolism via cellular respiration can be grouped into three major metabolic stages, these are (1) glycolysis, (2) the Krebs cycle also known as the citric acid cycle, and the tricarboxylic acid cycle (TCA cycle), and (3) the electron transport chain and oxidative phosphorylation. In eukaryotic cells, glycolysis occurs in the cytoplasm of the cell. The Krebs cycle occurs in the mitochondrial matrix while the reactions of the electron transport chain and oxidative phosphorylation occur on the cristae of the mitochondrion. These pathways rely on oxidation reduction reactions in which electrons are enzymatically removed (oxidation) from glucose and transferred (reduction) to electron acceptor molecules such as nicotinamide adenine dinucleotide (NAD+). Upon receiving electrons, NAD+ is reduced to NADH which functions as an electron carrier that supplies electrons to an electron transport chain in mitochondria that will ultimately power ATP synthesis in the reactions known as oxidative ...
Hepatic organelle interaction. II. Effect of tricarboxylic aci...
Citric Acid Cycle or Krebs Cycle - DnaTube.com - Scientific Video and Animation Site
RCSB PDB - 2CGO: FACTOR INHIBITING HIF-1 ALPHA with fumarate Structure Summary Page
Citrate synthase, mitochondrial
The protein encoded by this gene is a Krebs tricarboxylic acid cycle enzyme that catalyzes the synthesis of citrate from oxaloacetate and acetyl coenzyme A. The enzyme is found in nearly all cells capable of oxidative metablism. This protein is nuclear encoded and transported into the mitochondrial matrix, where the mature form is found. [provided by RefSeq, Jul 2008 ...
In this study, we focused on the analysis of proteins with basic pI values, most of which were missed by most researchers in previous proteomic studies of CRC (7, 10, 12). Although there are equal amounts of proteins with basic (,7) or acidic (,7) pI values in most eukaryotic organisms (13), most important cytosolic glycolytic and mitochondrial tricarboxylic acid cycle enzymes are basic proteins as demonstrated by the proteomic analysis of human colon crypt (15) and further confirmed by our study.. Glycolysis has been shown to be elevated in almost all cancers, the so-called "Warburg effect" (23). And many cancers show dysfunction of mitochondria (14, 23, 24). The increased aerobic glycolysis for ATP generation in cancer cells is frequently associated with mitochondrial respiration defects and hypoxia (25, 26). A recent report showed that inhibition of glycolysis in colon cancer cells could overcome drug resistance (against common anticancer agents) associated with mitochondrial respiratory ...
Succinate retention: the core Krebs dysfunction in immune-inflammatory disorders. - Free Online Library
Biology-Online • View topic - TAG's VS GLYCOGEN
Secondly, the 39ATPs are calculated from the degradtion of glucose during glycolysis during one complete cycle going through all the steps to the breakdown to pyruvate and then through the citric acid cycle. Depending on several factors in the citric acid cycle the amount can come down to 36, 38 or 39 ATPs. This might seem confusing but it all depends on whether endproducts are used in other cycles as well, if theyre used for anabolism the final yield will of course be less since this consumes ATP. Just remember that breakdown of glucose through oxidative phosphoryylation yields about 36-39 ATPs, much less than just breaking down glucose to lactic acid ...
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Sandwalk: The evolution of the citric acid cycle
The irreducibly complex biochemical systems that I have discussed in this book did not have to be produced recently. It is entirely possible, based simply on an examination of the systems themselves, that they were designed billions of years ago and that they have been passed down to the present by the normal processes of cellular reproduction. Perhaps a speculative scenario will illustrate the point. Suppose that nearly four billion years ago the designer made the first cell, already containing all of the irreducibly complex biochemical systems discussed here and many others. (One can postulate that the designs for systems that were to be used later, such as blood clotting, were present but not turned on. In present-day organisms plenty of genes are turned off for a while, sometimes for generations, to be turned on at a later time.) Additionally. suppose the designer placed into the cell some other systems for which we cannot adduce enough evidence to conclude design. The cell containing the ...
Citric Acid Cycle
Research Grants - 2008
Oxidative stress involves damage to cellular structures caused by free radicals, or toxic oxygen molecules. Free radicals are normal byproducts of cellular activities, and the bodys natural defenses normally hold them in check. However, these defenses appear to decline with age, and oxidative stress may contribute to cell damage in Alzheimers disease. Many investigators are studying the precise biological mechanisms behind oxidative stress and its effects on the Alzheimer brain. In preliminary research, Qingli Shi, Ph.D., and colleagues have found that Alzheimer-related oxidative stress alters the transcription, or "activation," of certain enzymes from the genes that encode them. These enzymes exist in mitochondria, cellular structures that use oxygen and nutrients to produce energy for a cell. The enzymes are involved in a process called the tricarboxylic acid (TCA) cycle. Altered TCA cycle enzymes may inhibit the TCA cycle process and reduce the brains ability to break down harmful ...
tricarboxylic acid metabolic process Antibodies | Invitrogen ...
The TCA Cycle
Since it is well known that ATP is the energy currency that is used for nearly every task in the human body and other organisms, it may seem surprising that so little ATP is produced directly by the TCA cycle. But the TCA cycle as shown here represents the process taking place in the matrix of the mitochondria using the reactions with NAD+ and FAD which carry high energy electrons to the electron transport systems in the inner mitochondrial membrane. The reactions there are responsible for the production of most of the ATP yield by chemiosmosis.. ...
BIOCHEMISTRY | Università degli Studi di Parma
Introduction to the metabolism - Catabolism. Anabolism. General aspects of metabolism regulation. Carbohydrates metabolism: digestion and absorption of carbohydrates. Glyolysis. Synthesis and catabolism of glycogen. The pentose pathway. The Krebs citric acid cycle. Gluconeogenesis. Lipid metabolism: digestion and absorption of fat. Fatty acids b-oxidation. Synthesis and oxidation of ketone bodies. Biosynthesis of fatty acids. Structure and function of cholesterol. Amino acid metabolism: digestion of proteins and absorption of amino acids. Essential and non-essential aminoacids. Main reactions of amino acids: deamination and transamination. Fate of the amino group and ammonia. The urea cycle. Decarboxylation ...
Insulin Resistance and Hyperglycemia : The Cellular Metabolism of What Leads to Type-2 Diabetes | Body Mind Soul
This is the intro and conclusion to the paper I just handed in. I cut out all the middle /good stuff because if you arent into cell metabolism, it is probably not of interest.IntroductionHyperglycemia enhances the uptake of glucose into the liver, which thus increases the metabolic pathways of glycolysis, the citric acid cycle, and…
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Rafael Pharmaceuticals - CPI-613
Developed as part of Rafaels proprietary Altered Energy Metabolism Directed (AEMD) drug platform, CPI-613 was discovered at Stony Brook University. CPI-613 is designed to target the mitochondrial tricarboxylic acid (TCA) cycle, an indispensable process essential to tumor cell multiplication and survival, selectively in cancer cells.. CPI-613s attack on the TCA cycle also substantially increases the sensitivity of cancer cells to a diverse range of chemotherapeutic agents. This synergy allows for combinations of CPI-613 with lower doses of these generally toxic drugs to be highly effective with lower patient side effects. Combinations with CPI-613 represent a diverse range of potential opportunities to substantially improve patient benefit in many different cancers.. ...
Fatty acid synthesis Cholesterol synthesis The citric acid cycle which in turn leads to: Amino acid synthesis Nucleotide ... The resulting acetyl-CoA enters the citric acid cycle (or Krebs Cycle), where the acetyl group of the acetyl-CoA is converted ... Metabolism portal Molecular and cellular biology portal Carbohydrate catabolism Citric acid cycle Cori cycle Fermentation ( ... beta-oxidation of fatty acids, and during the citric acid cycle). The NADH thus produced is primarily used to ultimately ...
The citric acid cycle, also known as the Krebs cycle or the TCA (tricarboxylic acid) cycle is an 8-step process that takes the ... "Citric Acid Cycle" (PDF). Takusagawa's Note. Archived from the original (PDF) on 24 March 2012. Retrieved 4 April 2013. " ... ADP cycling supplies the energy needed to do work in a biological system, the thermodynamic process of transferring energy from ... During the initial phases of glycolysis and the TCA cycle, cofactors such as NAD+ donate and accept electrons that aid in the ...
Pyruvate dehydrogenase (lipoamide) beta
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 ...
Pyruvate dehydrogenase (lipoamide) alpha 2
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, ...
Pyruvate dehydrogenase (lipoamide) alpha 1
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 ...
1981 in science
Pyruvate dehydrogenase (acetyl-transferring)
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 ...
Pyruvate dehydrogenase deficiency
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 ... doi:10.1016/S0076-6879(02)49317-2. ISBN 978-0-12-182252-1. Takusagawa F. "Chapter 16: Citric Acid Cycle" (PDF). Takusagawa's ... and thus the citric acid cycle is halted. The iron sulfur cluster is highly sensitive to oxidation by superoxide. Aconitase ...
Szent-Györgyi concurrently elucidated much of the citric acid cycle. In the 1930s, William Cumming Rose identified essential ... Fatty acids such as conjugated linoleic acid, catalpic acid, eleostearic acid and punicic acid, in addition to providing energy ... As there is no protein or amino acid storage provision, amino acids must be present in the diet. Excess amino acids are ... Most fatty acids are non-essential, meaning the body can produce them as needed, generally from other fatty acids and always by ...
Caloric restriction mimetic
Oxaloacetate is a metabolic intermediate of the citric acid cycle. In the short-lived roundworm Caenorhabditis elegans, ... Therefore, it has similar effects as CR. Lipoic Acid (α-Lipoic Acid, Alpha Lipoic Acid, or ALA) has failed to ... 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 ...
Inborn errors of carbohydrate metabolism
... and through the citric acid cycle (CAC) (see below, c.f. bioenergetic systems). The liver can also create glucose ( ... the pyruvate not converted feeds the citric acid cycle (CAC); both via pyruvate dehydrogenase (PDC, with Acetyl-CoA as ... cells also use the enzyme acid alpha-glucosidase in lysosomes to degrade glycogen. An deficiency of an involved enzyme results ...
... is also present in the citric acid cycle. The ester bond acts as a good electron donor due to resonance, and ... For diethyl succinate, the carboxylic acid involved is succinic acid, or butanedioic acid, which is a dicarboxyllic acid. The ... Diethyl succinate plays a key role in the Krebs cycle, which is a component of metabolism. Since it is low in molecular weight ... RCOOH + R'OH ↔ RCOOR' + water Fisher esterification is a common method of synthesis in which the carboxylic acid reacts with an ...
Szent-Györgyi concurrently elucidated much of the citric acid cycle. In the 1930s William Cumming Rose identified essential ... The omega-3 eicosapentaenoic acid (EPA), which can be made in the human body from the omega-3 essential fatty acid alpha- ... An appropriate balance of essential fatty acids - omega-3 and omega-6 fatty acids - seems also important for health, though ... Other essential nutrients not classed as vitamins include essential amino acids (see above), essential fatty acids (see above ...
... which is fully oxidized to carbon dioxide by the citric acid cycle (also known as the Krebs cycle). Every "turn" of the citric ... The citric acid cycle is regulated mainly by the availability of key substrates, particularly the ratio of NAD+ to NADH and the ... Although the citric acid cycle itself does not involve molecular oxygen, it is an obligately aerobic process because O2 is used ... In the absence of oxygen, the citric acid cycle ceases. The generation of ATP by the mitochondrion from cytosolic NADH relies ...
Outline of cell biology
Pyruvate dehydrogenase - Citric acid cycle - Also known as the Krebs cycle, an important aerobic metabolic pathway. Electron ... Hans Adolf Krebs - Discovered the citric acid cycle in 1937. Konstantin Mereschkowski - Russian botanist who in 1905 described ... DNA - Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions used in the development and ... DNA helicase DNA polymerase DNA ligase RNA - Ribonucleic acid is a nucleic acid made from a long chain of nucleotide, in a cell ...
... usually enters the citric acid cycle in humans as oxaloacetate. In bacteria, the degradation of ... asparagine leads to the production of oxaloacetate which is the molecule which combines with citrate in the citric acid cycle ( ... Asparagine (abbreviated as Asn or N), encoded by the codons AAU and AAC, is an α-amino acid that is used in the biosynthesis of ... It contains an α-amino group (which is in the protonated −NH+ 3 form under biological conditions), an α-carboxylic acid group ( ...
Succinate-CoA ligase (GDP-forming)
... instead pyruvate is formed and transmitted through the citric acid cycle). Muscle cells also contain globules of fat, which are ... Acidification by lactic acid may allow recovery of force so that acidosis may protect against fatigue rather than being a cause ... Once thought to be caused by lactic acid build-up, a more recent theory is that it is caused by tiny tears in the muscle fibers ... Since lactic acid disperses fairly rapidly, it could not explain pain experienced days after exercise. Humans are genetically ...
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 ... In tumor cells the citric acid cycle is truncated due to an inhibition of the enzyme aconitase (EC 184.108.40.206) by high ... Glutaminolysis partially recruits reaction steps from the citric acid cycle and the malate-aspartate shuttle. The conversion of ...
Oxoglutarate dehydrogenase complex
Oxoglutarate dehydrogenase is a key control point in the citric acid cycle. It is inhibited by its products, succinyl CoA and ... This enzyme participates in three different pathways: Citric acid cycle (KEGG link: MAP00020) Lysine degradation (KEGG link: ... most commonly known for its role in the citric acid cycle. Much like pyruvate dehydrogenase complex (PDC), this enzyme forms a ... The reaction catalyzed by this enzyme in the citric acid cycle is: α-ketoglutarate + NAD+ + CoA → Succinyl CoA + CO2 + NADH ...
Complete glucose breakdown
1937 in science
Electron transport chain - Simple English Wikipedia, the free encyclopedia
... and either a complete or partial citric acid cycle. These similarities to other organisms probably reflect both early ... Role in chemical cyclingEdit. Further information: Biogeochemical cycle. Archaea recycle elements such as carbon, nitrogen and ... Archaea are a major part of Earth's life and may play roles in both the carbon cycle and the nitrogen cycle. No clear examples ... Deppenmeier, U. (2002). "The unique biochemistry of methanogenesis". Prog Nucleic Acid Res Mol Biol. Progress in Nucleic Acid ...
citric acid cycle. *Citrate synthase. *Aconitase. *Isocitrate dehydrogenase. *Oxoglutarate dehydrogenase complex. *Succinyl ... MT-TI is a small 69 nucleotide RNA (human mitochondrial map position 4263-4331) that transfers the amino acid isoleucine to a ... May 2003). "A homoplasmic mitochondrial transfer ribonucleic acid mutation as a cause of maternally inherited hypertrophic ...
Pyruvate dehydrogenase (lipoamide) alpha 2
Voet DJ, Voet JG, Pratt CW (2010). "Chapter 17, Citric Acid Cycle". Principles of Biochemistry (4th ed.). Wiley. p. 550. ISBN ... tricarboxylic acid cycle. • oxidation-reduction process. • acetyl-CoA biosynthetic process from pyruvate. • glucose metabolic ... 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, ...
... superoxide inactivates the citric acid cycle enzyme aconitase, can poison energy metabolism, and releases potentially toxic ... as all ingested SOD is broken down into amino acids before being absorbed. However, ingestion of SOD bound to wheat proteins ... and their active sites contain the same type and arrangement of amino acid side-chains. They are usually dimers, but ... "Effects of tempol and redox-cycling nitroxides in models of oxidative stress". Pharmacology & Therapeutics. 126 (2): 119-45. ...
Citric acid cycle. Main article: Citric acid cycle. This is also called the Krebs cycle or the tricarboxylic acid cycle. When ... The citric acid cycle is an 8-step process involving 18 different enzymes and co-enzymes. During the cycle, acetyl-CoA (2 ... In the presence of oxygen, when acetyl-CoA is produced, the molecule then enters the citric acid cycle (Krebs cycle) inside the ... Glycolysis → Pyruvate decarboxylation → Citric acid cycle → Oxidative phosphorylation (electron transport chain + ATP synthase) ...
Citric acid cycle. *Pyruvate dehydrogenase deficiency. *Fumarase deficiency. Electron transport chain. *Coenzyme Q10 deficiency ... Their function is to convert the potential energy of glucose, amino acids, and fatty acids into adenosine triphosphate (ATP) in ... Succinic acid has been studied, and shown effective for both Leigh syndrome, and MELAS syndrome. A high-fat, low- ... Assessing the level of organic acids in urine can also indicate a dysfunction in the metabolic pathway. ...
Calvin cycle. *Chemical equation. *Chemical looping combustion. *Citric acid cycle. *Electrochemical series ... Top: ascorbic acid (reduced form of Vitamin C). Bottom: dehydroascorbic acid (oxidized form of Vitamin C) ... This catalytic behavior has been described as a futile cycle or redox cycling. ... The oxidation of iron(II) to iron(III) by hydrogen peroxide in the presence of an acid: Fe2+ → Fe3+ + e−. H2O2 + 2 e− → 2 OH−. ...
Hans Adolf Krebs
... "citric acid cycle". It is also known as the "Krebs cycle" or "tricarboxylic acid (TCA) cycle". ... Glyoxylate cycle. Krebs continued to add more details to his citric acid cycle. The discovery of acetyl-CoA in 1947 by ... Citric acid cycle (Krebs cycle). At the University of Sheffield, Krebs and William Johnson investigated cellular ... With Hans Kornberg, he also discovered the glyoxylate cycle, which is a slight variation of the citric acid cycle found in ...
... instead pyruvate is formed and transmitted through the citric acid cycle). Muscle cells also contain globules of fat, which are ... If oxygen is not available, pyruvic acid is converted to lactic acid, which may contribute to muscle fatigue. This occurs ... Acidification by lactic acid may allow recovery of force so that acidosis may protect against fatigue rather than being a cause ... Once thought to be caused by lactic acid build-up, a more recent theory is that it is caused by tiny tears in the muscle fibers ...
... or fed into the citric acid cycle. This use of protein as a fuel is particularly important under starvation conditions as it ... The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino ... If amino acids are present in the environment, microorganisms can conserve energy by taking up the amino acids from their ... Proteins are assembled from amino acids using information encoded in genes. Each protein has its own unique amino acid sequence ...
It is only the lactate and the waste products of the citric acid cycle that are returned to the blood. The liver can take up ... to glucose-6-phosphate and thence to pyruvate to be fed into the citric acid cycle or turned into lactate. ... Main articles: Acid-base homeostasis and Acid-base imbalance. The plasma pH can be altered by respiratory changes in the ... An important function is the production and control of bile acids. Too much bile acid can be toxic to cells and its synthesis ...
Metabolism: Citric acid cycle enzymes. Cycle. *Citrate synthase. *Aconitase. *Isocitrate dehydrogenase. *Oxoglutarate ... 3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), 2-keto-4-thiomethyl butyric acid and 4-aminoantipyrine. ... Its amino acid sequence is highly conserved in eukaryotes, differing by only a few residues. In more than thirty species, 34 of ... Many higher-order organisms possess a chain of 104 amino acids. The sequences of cytochrome c in humans is identical to that ...
Fumarate is an intermediate in the citric acid cycle used by cells to produce energy in the form of adenosine triphosphate (ATP ... It is one of two isomeric unsaturated dicarboxylic acids, the other being maleic acid. In fumaric acid the carboxylic acid ... at a rate of 1 g of fumaric acid to every ~1.5 g of citric acid, in order to add sourness, similarly to the way malic acid is ... Fumaric acid or trans-butenedioic acid is the chemical compound with the formula HO2CCH=CHCO2H. Fumaric acid has a fruit-like ...
اکسیژن - ویکیپدیا، دانشنامهٔ آزاد
Other important organic compounds that contain oxygen are: glycerol, formaldehyde, glutaraldehyde, citric acid, acetic ... Walker, J. C. G. (1980). The oxygen cycle in the natural environment and the biogeochemical cycles. Berlin: Springer-Verlag.. ... acetic acid, and formic acid. Acetone ((CH. 3). 2CO) and phenol (C. 6H. 5OH) are used as feeder materials in the synthesis of ... The unusually high concentration of oxygen gas on Earth is the result of the oxygen cycle. This biogeochemical cycle describes ...
Coenzyme A - Simple English Wikipedia, the free encyclopedia
vitamin C, discovering the components and reactions of the citric acid cycle. ... He is credited with discovering vitamin C and the components and reactions of the citric acid cycle. He was also active in the ... identifying fumaric acid and other steps in what would become known as the Krebs cycle. In Szeged he also met Zoltán Bay, ... He received his PhD from Fitzwilliam College, Cambridge in 1927 for work on isolating an organic acid, which he then called " ...
ಟೆಂಪ್ಲೇಟು:Central nervous system navs - ವಿಕಿಪೀಡಿಯ
Engineered amino acids. *Expanded genetic code. Intermediates. Mitochondria citric acid cycle. *Ornithine ... The organic compound citrulline is an α-amino acid. Its name is derived from citrullus, the Latin word for watermelon, from ... Citrulline is also produced as a byproduct of the enzymatic production of nitric oxide from the amino acid arginine, catalyzed ... Citrulline is made from ornithine and carbamoyl phosphate in one of the central reactions in the urea cycle. It is also ...
Citric. Acid Cycle. Glyoxylate. Cycle. Urea. Cycle. Fatty. Acid. Synthesis. Fatty. Acid. Elongation ... creating the four-carbon organic acid oxaloacetic acid. Oxaloacetic acid or malate synthesized by this process is then ... the photosynthetic carbon reduction cycle) in plants. The carbon reduction cycle is known as the Calvin cycle, which ignores ... Many scientists refer to the cycle as the Calvin-Benson Cycle, Benson-Calvin, and some even call it the Calvin-Benson-Bassham ( ...
... increased amino acid catabolism, inhibition of the citric acid cycle, lactic acidosis, ketoacidosis, hyperuricemia, disturbance ... Tolfenamic acid, an inhibitor of prostaglandin synthesis, in a 1983 study reduced headache, nausea, vomiting, irritation but ... Metabolism of methanol produces some extremely toxic compounds, such as formaldehyde and formic acid, which may play a role in ... In addition, about half of all East Asians convert acetaldehyde to acetic acid more slowly (via acetaldehyde dehydrogenase), ...
Reverse Krebs cycle
The reverse Krebs cycle (also known as the reverse tricarboxylic acid cycle, the reverse TCA cycle, or the reverse citric acid ... The reaction is the citric acid cycle run in reverse: Where the Krebs cycle takes complex carbon molecules in the form of ... Calvin Cycle. References. *^ Evans MC; Buchanan BB; Arnon DI (April 1966). "A new ferredoxin-dependent carbon reduction ... It has been found that some non-consecutive steps of the cycle can be catalyzed by minerals through photochemistry, while ...
List of Nobel Prize winners in Physiology or Medicine - Simple English Wikipedia, the free encyclopedia
1953 - Hans Krebs, United Kingdom, for his discovery of the citric acid cycle. ... 1937 - Albert Szent-Györgyi, Hungary, for his discoveries about cells, vitamin C and chemical changes of fumaric acid. ... 1922 - Otto Fritz Meyerhof, Germany, for finding out how oxygen makes chemical changes in lactic acid in muscles ... 1959 - Arthur Kornberg and Severo Ochoa, United States, for their discovery of how living things make ribonucleic acid (RNA) ...
Citric acid cycle variants at MetaCyc. *((. en. )) Pathways connected to the citric acid cycle at KEGG,Kyoto Encyclopedia of ... Barnes, SJ; Weitzman, PD (April 1986). "Organization of citric acid cycle enzymes into a multienzyme cluster". FEBS Lett. 201 ( ... Notes on citric acid cycle at rahulgladwin.com. *((. en. )) ... Citric acid cycle Animation(flash required). *((. en. )) An ... A citric-acid cycle self quiz flash applet at University of Pittsburgh ...
Malate dehydrogenases that catalyse the interconversion of malate to oxaloacetate and participate in the citric acid cycle, and ... This leads to the addition of seven amino acid acids to the normal LDH-H protein. The extension contains a peroxisomal ... The LDHBx protein is seven amino acids longer than the LDHB (LDH-H) protein. This amino acid extension is generated by ... LDHBx is generated by translation of the LDHB mRNA, but the stop codon is interpreted as an amino acid-encoding codon. In ...
PDH links glycolysis to the citric acid cycle, while the reaction catalyzed by OGDH is a rate-limiting step in the citric acid ... Thiamine and its acid metabolites (2-methyl-4-amino-5-pyrimidine carboxylic acid, 4-methyl-thiazole-5-acetic acid, and thiamine ... Some examples of these antagonists are caffeic acid, chlorogenic acid, and tannic acid. These compounds interact with the ... "Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and ...
Chelating agents (e.g. DTPA, citric acid, or EDTA) are often added to increase iron solubility over a greater pH range.. ... For example, at the end of an annual plant's life cycle, a plant should be restricted from high nitrogen fertilizers. In most ... while application of a biostimulator consisting of humic acid, lactic acid and Bacillus subtilis improved yields in all ... In addition to chelating agents, humic acids can be added to increase nutrient uptake. ...
Biyokimika, ang malayang ensiklopedya
... citric acid cycle) na nagbubunga pa ng dalawang molekula ng ATP, anim pang NADH at dalawang kaanak na molekula ng FADH2, at ... Ito ang tinatawag na mga kailangang asido amino (essential amino acids) dahil kailangan kainin ito mula sa mga pagkain. Ang mga ... Kapag ang grupong amino ay inalis sa isang asido amino, nagiiwan ito ng isang kalansay ng carbon na tinatawag na α-keto acid. ... nonessential amino acids). Dahil hindi nakagagawa ng sapat na dami ng arginine at histidine ang mga ito para sa mga bata at ...
Citric acid cycle - Wikipedia
The citric acid cycle (CAC) - also known as the TCA cycle (tricarboxylic acid cycle) or the Krebs cycle - is a series of ... Citric acid cycle variants at MetaCyc. *Pathways connected to the citric acid cycle at Kyoto Encyclopedia of Genes and Genomes ... Citric Acid Cycle. Boston: Academic Press. ISBN 0-12-181870-5.. *^ Kay J, Weitzman PD (1987). Krebs citric acid cycle: half a ... However, because of the role of the citric acid cycle in anabolism, they might not be lost, since many citric acid cycle ...
Citric Acid Cycle - Proteopedia, life in 3D
Citric acid cycles Synonyms, Citric acid cycles Antonyms | Thesaurus.com
Synonyms for citric acid cycles at Thesaurus.com with free online thesaurus, antonyms, and definitions. Dictionary and Word of ... citric acid cycles. star. see definition of citric acid cycles show all. noun. ... More words related to citric acid cycles. Krebs cycle noun. series of enzymatic reactions ... citric acid cycle Relevance Relevance ranks synonyms and suggests the best matches based on how closely a synonyms sense ...
Citric Acid Cycle or Krebs Cycle - DnaTube.com - Scientific Video and Animation Site
... citric acid is first consumed and then regenerated in a sequence of reactions. All aerobic organisms use this cycle to generate ... Citric Acid Cycle or Krebs Cycle In this cycle,citric acid is first consumed and then regenerated in a sequence of reactions. ... Tags: citric acid cycle cell biology Uploaded by: sana ( Send Message ) on 27-05-2009. Dnatube suggest users to have interest ...
Sandwalk: The evolution of the citric acid cycle
13.9 Evolution of the Citric Acid Cycle. The reactions of the citric acid cycle were first discovered in mammals and many of ... Most species of bacteria do not have a complete citric acid cycle. The most common versions of an incomplete cycle include part ... I am banging my head on glycoslysis, the citric acid cycle the calvin cycle and the stoichiometry of the oxidative ... Some bacteria have a complete citric acid cycle but it is used in the reductive direction to fix CO2 in order to build more ...
Citric Acid Cycle
... also known as the Krebs cycle or the tricarboxylic acid cycle, is at the center of cellular metabolism, playing a ... The citric acid cycle, also known as the Krebs cycle or the tricarboxylic acid cycle, is at the center of cellular metabolism, ... One GTP or ATP is also made in each cycle. Several of the intermediate compounds in the citric acid cycle can be used in ... a key component of the cycle. The citric acid cycle itself was finally identified in 1937 by Hans Adolf Krebs and William ...
L18-Mitochondria and Citric Acid Cycle | MindMeister Mind Map
... citric acid cycle background. 4.1. citric acid cycle=central metabolic hub of the cell. 4.2. function of the citric acid cycle ... 220.127.116.11.1. oxaloacetate replenishes the citric acid cycle. 7.3. as citric acid cycle=cycle. 7.3.1. can be replenished by ... 8. Control of the citric acid cycle. 8.1. rate of the citric acid cycle has to meet the demand for ATP in an animal cell. 8.1.1 ... 2.2.1. mitochondria contain the respiratory assembly, the enzymes of the citric acid cycle, and the enzymes of fatty acid ...
Lecture: 4 Biochemistry Anwar J Almzaiel. Citric acid cycle - PDF
Krebs cycle, tricarboxylic acid cycle) is a series of reactions in mitochondria that bring about the catabolism of acetyl ... Enzymes of the Citric Acid Cycle. Regulation of the Citric Acid Cycle Citric Acid Cycle Cycle Overview Metabolic Sources of ... 1 Citric acid cycle Citric acid cycle (Krebs cycle, tricarboxylic acid cycle) is a series of reactions in mitochondria that ... A Enzymes of the Citric Acid Cycle Regulation of the Citric Acid Cycle The Amphibolic Nature of the Citric Acid Cycle Cycle ...
Solution - Distinguish Between Glycolysis and Citric Acid Cycle - Glycolysis | shaalaa.com
Citric Acid Cycle and Oxidative Phosphorylation | Open Textbooks for Hong Kong
The citric acid cycle is a series of chemical reactions that removes high-energy electrons and uses them in the electron ... non-essential amino acids, sugars, and lipids. These same molecules, except nucleic acids, can serve as energy sources for the ... A number of intermediate compounds can be diverted into the anabolism of other biochemical molecules, such as nucleic acids, ... One molecule of ATP (or an equivalent) is produced per each turn of the cycle. ...
Citric acid cycle - Wikipedia
The citric acid cycle (CAC) - also known as the TCA cycle (tricarboxylic acid cycle) or the Krebs cycle - is a series of ... Citric acid cycle variants at MetaCyc. *Pathways connected to the citric acid cycle at Kyoto Encyclopedia of Genes and Genomes ... 8 Major metabolic pathways converging on the citric acid cycle. *9 Citric acid cycle intermediates serve as substrates for ... However, because of the role of the citric acid cycle in anabolism, they might not be lost, since many citric acid cycle ...
Category:Citric acid cycle - Wikimedia Commons
Krebs cycle, TCA cycle, GO:0006099, citric acid cycle (en); حلقة حمض الليمون, دوره حمض الستريك, دورة الحموض ثلاثية الكربوكسيل, ... Krebs cycle, tricarboxylic acid cycle, TCA cycle (en-ca); 크레브스 회로, TCA회로, 구연산 회로, 크렙스 회로, 시트르산 회로 (ko); TCAサイクル, TCAC, クレブス回路, ... Krebs cycle, tricarboxylic acid cycle, TCA cycle (en-gb); چرخه تریکربوکسیلیک اسید, چرخه کربس, چرخهٔ اسید سیتریک, کریپس سایکل, ... Media in category "Citric acid cycle". The following 180 files are in this category, out of 180 total. ...
RhymeZone: citric acid cycle definitions
citric acid cycle (thing) by BioTech - Everything2.com
A complex series of reactions following glycolysis in aerobic respiration that convert pyruvic acid into hydrogen, carbon ... citric acid cycle (thing). See all of citric acid cycle, no other writeups in this node. ... More commonly known as the Krebs cycle, and less commonly known as the tricarboxylic acid cycle. ... A complex series of reactions following glycolysis in aerobic respiration that convert pyruvic acid into hydrogen, carbon ...
Krebs / citric acid cycle (video) | Khan Academy
Overview of the Krebs or citric acid cycle, which is a series of reactions that takes in acetyl CoA and produces carbon dioxide ... or the Krebs cycle or the citric acid cycle gets credit for this step. But its really a preparation step for the Krebs cycle. ... The Krebs cycle, or the citric acid cycle. And that actually takes place in the inner membrane, or I should say the inner space ... Now, in the citric acid cycle, or in the Krebs cycle, well first we have our pyruvate oxidation. That produced one NADH. But ...
Linked cycles of oxidative decarboxylation of glyoxylate as protometabolic analogs of the citric acid cycle | Nature...
The citric acid cycle (TCA) is a fundamental metabolic pathway to release stored energy in living organisms. Here, the authors ... cycle, have languished-primarily due to a lack of experimentally demonstrable and sustainable cycle(s) of reactions. We show ... These results indicate that simpler versions of metabolic cycles could have emerged under potential prebiotic conditions, ... linked cycles of reactions that each oxidize glyoxylate into CO2 and generate intermediates shared with the modern TCA cycle, ...
Structural Biochemistry/Krebs Cycle (Citric Acid cycle) - Wikibooks, open books for an open world
Citric Acid Cycle. Other name for citric acid cycle is tricarboxylic acid (TCA) cycle or the Krebs cycle. The citric acid ... Regulatory Enzyme in Citric Acid Cycle. In animal cells, the rate of citric acid cycle is regulated to fitted the ... Structural Biochemistry/Krebs Cycle (Citric Acid cycle). From Wikibooks, open books for an open world ... Citric Acid Cycle Links to Glycolysis by Pyruvate Dehydrogenase. Carbohydrates are mostly processed by glycolysis into ...
citric acid cycle
Glicerina biotecnologia | Glycolysis | Citric Acid Cycle
acid, lactic acid, betaine, potassium sulfate, l-pyroglutamic acid,. and free flowing distillers dry grain and solubles or a ... amino acids [25,32]. Furthermore, aerobic oxidation of. pyruvatevia pyruvate dehydrogenase and the TCA cycle. enzymesproduces ... acid that is excreted from the cells cannot diffuse back into. the cells, since the ionic form of acetic acid predominates. at ... amino acid synthesis . It has also been reported that the. activity of ADH is decreased when amino acids rather than. ...
The Citric Acid Cycle - Course Hero
This lesson provides helpful information on The Citric Acid Cycle in the context of Cellular Respiration to help students study ... The Citric Acid Cycle. The citric acid cycle consists of a series of steps used to catalyze products following the oxidation of ... Steps of the Citric Acid Cycle. The citric acid cycle starts after the oxidation of pyruvate. It consists of eight sequential ... Citric Acid Cycle Net Reaction. The citric acid cycle uses multiple reactions for the release of energy. ...
Glycolysis & Respiration | Cellular Respiration | Citric Acid Cycle
6 NADH from the Krebs cycle allow the production of 15 ATP. 2 FADH from Krebs cycle allow the production of 3 ATP. e eukaryotes ... Krebs cycle. cycle.. In eukaryotes, all steps. of respiration occur in. the mitochondrion.. 10 ... and the Krebs cycle are used to produce ATP through. chemiosmosis. O2 is the final acceptor of high energy electrons.. In ... Krebs Cycle:. 2 Acetyl Co-A 4 CO2 + 2 ATP + 6 NADH + 2 FADH. Electron transport system (ETS):. 2 NADH from glycolysis allow ...
Experts and Doctors on citric acid cycle in United States
Species about Experts and Doctors on citric acid cycle in United States ... citric acid cycle*ketoglutarate dehydrogenase complex*ketoglutaric acids*keto acids*pyruvate dehydrogenase complex*heptanoates* ... IDH1 mutations alter citric acid cycle metabolism and increase dependence on oxidative mitochondrial metabolism. Cancer Res. ... Experts and Doctors on citric acid cycle in United States. Summary. Locale: United States ...
Biology, The Cell, Cellular Respiration, Oxidation of Pyruvate and the Citric Acid Cycle | OER Commons
Citric Acid Cycle Like the conversion of pyruvate to acetyl CoA, the citric acid cycle takes place in the matrix of ... Products of the Citric Acid Cycle. Two carbon atoms come into the citric acid cycle from each acetyl group, representing four ... the oxidation steps of the citric acid cycle also do not occur. Note that the citric acid cycle produces very little ATP ... This single pathway is called by different names: the citric acid cycle (for the first intermediate formed-citric acid, or ...
Citric acid cycle (TCA cycle) | Biology | Catabolism schematic - Biochemical diagram | Chart Of Tricarboxylic
Citric acid cycle. Wikipedia] ,br,This biochemical diagram example shows metabolic pathways map of citric acid cycle reactions ... creativecommons.org/licenses/by/3.0/deed.en] ,br,The metabolic pathway map example Citric acid cycle (TCA cycle) was created ... tricarboxylic acid cycle, TCA cycle, Krebs cycle) is a series of chemical reactions used by all aerobic organisms to generate ... br,This sample was redesigned from the Wikimedia Commons file: TCA cycle.svg. [commons.wikimedia.org/wiki/File:TCA_cycle.svg] , ...
Sandwalk: Biochemistry on the Web: The Citric Acid Cycle
find one single website that correctly shows the reactions of the citric acid cycle with all the correct substrates and ... Enzymes of the Citric Acid Cycle. citrate synthase [EC 18.104.22.168]. aconitase [EC 22.214.171.124]. isocitrate dehydrogenase [EC 126.96.36.199 ... In the direction of the citric acid cycle the electrons are passed from succinate to FAD+ to three Fe-S clusters and then to ... Here are some websites that discuss the Citric Acid Cycle [Krebs animation][Wikipedia]. This is one of the fundamental ...
Search: protein class:Citric acid cycle related proteins - The Human Protein Atlas
Cell cycle intensity correlation. Cell cycle spatial correlation. Cell cycle biologically. Custom data cell cycle dependant. - ... Citric acid cycle related proteins. Disease related genes. Enzymes. FDA approved drug targets. G-protein coupled receptors. ... Citric acid cycle related proteins. Disease related genes. Enzymes. Potential drug targets. Predicted intracellular proteins. ... Citric acid cycle related proteins. Disease related genes. Enzymes. Potential drug targets. Predicted intracellular proteins. ...
Modifications of citric acid cycle activity and gluconeogenesis in streptozotocin-induced diabetes and effects of metformin. |...
To better define the modifications of liver gluconeogenesis and citric acid cycle, or Krebs cycle, activity induced by insulin ... Modifications of citric acid cycle activity and gluconeogenesis in streptozotocin-induced diabetes and effects of metformin.. ... Modifications of citric acid cycle activity and gluconeogenesis in streptozotocin-induced diabetes and effects of metformin. ... Modifications of citric acid cycle activity and gluconeogenesis in streptozotocin-induced diabetes and effects of metformin. ...
Glycolysis & the Citric Acid Cycle - Video & Lesson Transcript | Study.com
The Citric Acid Cycle. Once weve finished with glycolysis, we can move onto stage two of respiration, the citric acid cycle, ... Glycolysis produces the molecules that are processed by the citric acid cycle. The citric acid cycle occurs in the mitochondria ... Still, this is a productive cycle, and it actually isnt over. Some of the molecules produced by the citric acid cycle will ... Just as with glycolysis, the citric acid cycle has two phases. In the first phase, pyruvate is oxidized to form Acetyl CoA. ...
2009--Real-time Assessment of Krebs Cycle Metabolism Using | Citric Acid Cycle | Glycolysis
Real-time Assessment of Krebs Cycle Metabolism Using - Free download as PDF File (.pdf), Text File (.txt) or read online for ... flux through citric acid cycle pathways in perfused heart by 13C. NMR spectroscopy. FEBS Lett. 212, 58 62. Malloy, C. R., ... reduced fatty acid oxidation, which raises the question. as to how Krebs cycle flux and cardiac energetics can be. maintained ... 29). Also, fatty acid metabolism contributes to Krebs. cycle recovery following ischemia (28, 37). Therefore,. these ...
The Citric Acid Cycle - The WikiPremed MCAT Course
The topic under discussion here is The Citric Acid Cycle - The WikiPremed MCAT Course ... fatty acids, and carbohydrates, are ultimately oxidized in aerobic metabolism by means of the citric acid cycle. Most enter the ... Kimballs Biology Pages - The Citric Acid Cycle. Online Biology Book - Aerobic Respiration. Basic introduction to aerobic ... The Citric Acid Cycle including the initial pyruvate mobilization is a series of reactions oxidizing the pyruvate from ...
WikiPremed MCAT Course - Regulation of the Citric Acid Cycle
Reactome | Citric acid cycle (TCA cycle)
Reactome | Citric acid cycle (TCA cycle)
Changes in the contents of adenine nucleotides and intermediates of glycolysis and citric acid cycle in flight muscle of the...
2. Calculations based on O2 uptake of the intact insect indicate that the rate of the citric acid cycle must be increased ,100- ... Changes in the contents of adenine nucleotides and intermediates of glycolysis and citric acid cycle in flight muscle of the ... Changes in the contents of adenine nucleotides and intermediates of glycolysis and citric acid cycle in flight muscle of the ... Changes in the contents of adenine nucleotides and intermediates of glycolysis and citric acid cycle in flight muscle of the ...
Exam4Notes - Chapter 11 The Citric Acid Cycle Learning Objectives Entry of Pyruvate into TCA cycle Roles of Coenzymes Steps of...
Chapter 11 The Citric Acid Cycle Learning Objectives Entry of Pyruvate into TCA cycle Roles of Coenzymes Steps of the TCA cycle ... Chapter 11 The Citric Acid Cycle Learning Objectives Entry of Pyruvate into TCA cycle Roles of Coenzymes Steps of the TCA cycle ... production site Control of cycle (p358) Cyclic versus linear pathways TCA Cycle for biosynthesis TCA Cycle Anaplerotic ... Why do unsaturated fatty acids yield less energy than saturated fatty acids A ...
IntermediatesGlucoseProteinsTricarboxylic acidEnzymesNADHPyruvicBiosynthesisFatty acidKrebs CycleCarbonKreb'sUrea cycleAerobic organismsAscorbicFattyReactionsBiochemistryMetabolismPathwaysEnzymes of the citriCellularFADH2Regulation of the Citri2020Market for citric acidUses citric acidForm citric acidSynthesisProduce citric acidGluconeogenesisBiologyAnhydrousEnzymeAconitase2016Soluble in waterStepsHigh energy electronsElectron transportAscorbic acidOxaloacetic acidIntermediateChapterAcetic Acid
- Two carbon atoms come into the citric acid cycle from each acetyl group, representing four out of the six carbons of one glucose molecule. (assignmentpoint.com)
- In the first phase glucose molecule partially breaks down to form 2 molecules of 3-carbon compound pyruvic acid. (biologyeducare.com)
- Glycolysis is the metabolic pathway where one molecule of glucose(C 6 H 12 O 6 ) converts into pyruvic acid by the help of enzyme. (biologyeducare.com)
- So in the overall process, two molecules of pyruvic acid is formed from each molecule of glucose. (biologyeducare.com)
- Hyperglycemia enhances the uptake of glucose into the liver, which thus increases the metabolic pathways of glycolysis, the citric acid cycle, and the generation of energy as ATP. (wordpress.com)
- Similarly, the mechanism behind impaired GLUT-4 translocation is also unclear, although other studies strongly indicate that elevation in free fatty acids decrease glucose transport and impair PI(3)K in skeletal muscle.4 The elevation in free fatty acids were associated with increased levels of serum RBP4, which were inversely correlated with GLUT-4 functioning. (wordpress.com)
- The citric acid cycle, also known as the Krebs cycle or the tricarboxylic acid cycle, is at the center of cellular metabolism, playing a starring role in both the process of energy production and biosynthesis. (assignmentpoint.com)
- The citric acid cycle , also known as the tricarboxylic acid cycle (TCA cycle) or the Krebs cycle, (or rarely, the Szent-Gyorgyi-Krebs cycle) is a series of enzyme-catalysed chemical reactions of central importance in all living cells that use oxygen as part of cellular respiration. (wikipathways.org)
- Kreb's cycle animation and Citric acid cycle : Central metabolic cycle and its Significance Citric acid cycle is also called Krebs Cycle and Tricarboxylic acid cycle. (biochemden.com)
- In this stage pyruvic acid is completely oxidized to form CO 2 , H 2 O and ATP. (biologyeducare.com)
- 8. 2 phosphoglyceric acid is then converted to form 2 phosphoenol pyruvic acid with the help of enzyme enolase which gives out one molecule of water. (biologyeducare.com)
- 9. It is the last step of glycolysis where 2 phosphoenol pyruvic acid is converted to form pyruvic acid by the removal of phosphorus thus one molecule of ATP is synthesized from ADP. (biologyeducare.com)
- The enzyme catalyzing this step is pyruvic acid kinase. (biologyeducare.com)
- 1) Specifically, I presented data concerning 24-hour urinary excretion of Krebs cycle metabolites in 236 patients. (thefreelibrary.com)
- and (2) succinate retention as the Krebs cycle dysfunction of highest clinical interest. (thefreelibrary.com)
- I reviewed Krebs cycle data for an additional 315 patients seen since my 2004 Townsend report. (thefreelibrary.com)
- Acetyl-CoA may also be obtained from the oxidation of fatty acids. (wikipedia.org)
- It is the final common pathway for oxidation - in other words harvesting high energy electrons--fuel molecules such as carbohydrate fatty acids, and amino acids by entering the cycle as Acetyl Coenzyme A (CoA). (wikibooks.org)
- This biochemical chart display how proteins, polysaccharides and fats from food are digested into gastrointestinal tract into aminoacids, monosaccharides and fatty acids, and then broken down and oxidized to carbon dioxide and water in cellular processes of energy generation. (conceptdraw.com)
- In the hypertrophic heart, fatty acid oxidation is decreased, with an increase in glycolysis (6, 7). (scribd.com)
- All fuel molecules, amino acids, fatty acids, and carbohydrates, are ultimately oxidized in aerobic metabolism by means of the citric acid cycle. (wikipremed.com)
- Describe the role of the citric acid cycle in fatty acid synthesis. (mhmedical.com)
- The citric acid cycle is the final common pathway for the oxidation of carbohydrate, lipid, and protein because glucose, fatty acids, and most amino acids are metabolized to acetyl-CoA or intermediates of the cycle. (mhmedical.com)
- The presence of a forked pathway (Figure 13.24) results in the synthesis of all the precursors of amino acids, porphyrins, and fatty acids. (blogspot.co.uk)
- The needed acetyl-CoA is created in the beta-oxidation of fatty acids and the oxidative decarboxylation of pyruvate , which forms during glycolysis. (lecturio.com)
- Reaction products from the citric acid cycle are diverted and fed into other metabolic pathways: citrate for fatty acid synthesis , oxaloacetate for gluconeogenesis , or succinyl-CoA for the formation of delta-aminolevulinic acid as the basic substance for heme synthesis . (lecturio.com)
- stimulates Fructose-1,6-bisPhosphatase , a key enzyme of Gluconeogenesis and activates Acetyl CoA carboxylase , key enzyme of Fatty acid synthesis. (biochemden.com)
- The source of acetyl CoA is glycolysis or the fatty acid spiral. (boekhandeldeoorsprong.nl)
- Acetyl CoA, the product of fatty acid ß-oxidation, is burned away as CO 2, as is pyruvic acid the product of sugar metabolism. (org.in)
- The citric acid cycle is the final common pathway for the oxidation of fuel molecules-amino acids, fatty acids, and carbohydrates. (boekhandeldeoorsprong.nl)
- The citric acid cycle serves as a metabolic traffic circle that receives carbon skeletons from amino acids and fatty acids and donates carbon skeletons to amino acids and porphyrins. (kroon-partners.nl)
- Citric acid cycle is the common pathway leading to complete oxidation of carbohydrates, fatty acids, and amino acids to CO2. (medworldonline.com)
- It is a cofactor in DNA synthesis, and in both fatty acid and amino acid metabolism. (integratedhealthblog.com)
- Other sources of acetyl CoA include breakdown of free fatty acids and ketone bodies in the fasting state. (reactome.org)
- The major function of cycle is to act as the final common pathway for oxidation of fatty acids, carbohydrates and proteins. (docplayer.net)
- The body used acetyl COA to form fatty acids, so when a person eats any high carbohydrate diet there will be formation of fatty acids which are stored in the form of lipid glycerol and triglycerides, while during fasting triglycerides converted into fatty acids and acetyl COA that enters citric acid cycle. (docplayer.net)
- Other molecules, such as fatty acids and proteins, can also serve as energy sources when they are funneled through appropriate enzymatic pathways. (nih.gov)
- In either case, the large polymeric molecules in food are broken down during digestion into their monomer subunits-proteins into amino acids, polysaccharides into sugars, and fats into fatty acids and glycerol -through the action of enzymes. (nih.gov)
- Recall from the experiment, 'Membranes and Proteins: Dialysis, Detergents, and Proton Gradients,' that the phospholipids that form cell membranes are formed from glycerol with a phosphate group and two fatty-acid chains attached. (wustl.edu)
- For example, the intermediate dihydroxyacetone phosphate (DHAP) is a source of the glycerol that combines with fatty acids to form fat. (wikipedia.org)
- The lower-energy production, per glucose, of anaerobic respiration relative to aerobic respiration, results in greater flux through the pathway under hypoxic (low-oxygen) conditions, unless alternative sources of anaerobically oxidizable substrates, such as fatty acids, are found. (wikipedia.org)
- Fuel molecules commonly used by cells in respiration include glucose , amino acids and fatty acids , and a common oxidizing agent ( electron acceptor ) is molecular oxygen (O 2 ). (wikidoc.org)
- the process is the chief source of mammalian energy, during which carbon chains of sugars, fatty acids, and amino acids are metabolized to yield carbon dioxide, water, and high-energy phosphate bonds. (thefreedictionary.com)
- In addition, the cycle provides precursors of certain amino acids, as well as the reducing agent NADH, that are used in numerous other biochemical reactions. (wikipedia.org)
- The name of this metabolic pathway is derived from the citric acid (a type of 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 reactions of the cycle are carried out by eight enzymes that completely oxidize acetate, in the form of acetyl-CoA, into two molecules each of carbon dioxide and water. (wikipedia.org)
- 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)
- 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 key component of the cycle. (wikipedia.org)
- A complex series of reactions following glycolysis in aerobic respiration that convert pyruvic acid into hydrogen , carbon dioxide and electron s. (everything2.com)
- The development of metabolic approaches towards understanding the origins of life, which have focused mainly on the citric acid (TCA) cycle, have languished-primarily due to a lack of experimentally demonstrable and sustainable cycle(s) of reactions. (nature.com)
- With this strategy, we discovered two linked cycles of reactions that each oxidize glyoxylate into CO 2 , and generate intermediates that are shared with the modern TCA cycle. (nature.com)
- Therefore, the pyruvate dehydrogenase relates to the reactions of the citric acid cycle itself. (wikibooks.org)
- The Citric Acid Cycle is a series of enzyme catalyzed reactions which are critical in cellular respiration. (proteopedia.org)
- The citric acid cycle uses multiple reactions for the release of energy. (coursehero.com)
- The eight steps of the cycle are a series of redox, dehydration, hydration, and decarboxylation reactions that produce two carbon dioxide molecules, one GTP/ATP, and reduced forms of NADH and FADH 2 ( Figure ). (oercommons.org)
- This biochemical diagram example shows metabolic pathways map of citric acid cycle reactions. (conceptdraw.com)
- This is the time of the year when I challenge the students in my introductory biochemistry class to find one single website that correctly shows the reactions of the citric acid cycle with all the correct substrates and products (including water and protons). (blogspot.com)
- The Citric Acid Cycle including the initial pyruvate mobilization is a series of reactions oxidizing the pyruvate from glycolysis to form three molecules of CO 2 . (wikipremed.com)
- As the pyruvic acid is incorporated into the citric acid cycle and then broken down by enzymatic reactions, carbon dioxide, hydrogen atoms, and electrons are released. (encognitive.com)
- In this cycle,citric acid is first consumed and then regenerated in a sequence of reactions. (dnatube.com)
- The components and reactions of the citric acid cycle were established by seminal work from both Albert Szent-Györgyi and Hans Krebs . (chemeurope.com)
- Other relevant reactions in the pathway include those in glycolysis and pyruvate oxidation before the citric acid cycle, and oxidative phosphorylation after it. (chemeurope.com)
- Describe the reactions of the citric acid cycle and the reactions that lead to the production of reducing equivalents that are oxidized in the mitochondrial electron transport chain to yield ATP. (mhmedical.com)
- They are safe for people with citric acid sensitivities to consume although they can cause reactions in people who are allergic to latex. (reference.com)
- The reactions of the citric acid cycle were first discovered in mammals and many of the key enzymes were purified from liver extracts. (blogspot.co.uk)
- Citric acid can cause many different allergic reactions in different people. (creationwiki.org)
- The definition for the citric acid cycle generally is a series of chemicals reactions in a cell that breaks down food molecules into carbon dioxide, water, and energy. (creationwiki.org)
- The eight enzymes of the citric acid cycle catalyze a series of well-known organic reactions that cumulatively oxidize an acetyl group to two CO2 molecules with the concomitant generation of three NADH and one FADH2, and one GTP. (biochemden.com)
- The cycle involves eight chemical reactions, and at the end, the original four-carbon molecule is produced. (org.in)
- The citric acid cycle is a series of redox and decarboxylation reactions that remove high-energy electrons and carbon dioxide. (boekhandeldeoorsprong.nl)
- The TCA cycle is a set of eight catalyzed reactions and eight intermediates that break down hydrocarbon substrates into carbon dioxide (CO2) and water (H2O) using the energy released to protonate nicotinamide adenine dinucleotide converting from NAD+ to NADH or flavin adenine dinucleotide from FADH to FADH2. (kroon-partners.nl)
- It is also a central hub in biosynthetic reactions, providing intermediates that are used to build amino acids and other molecules. (assignmentpoint.com)
- This lecture briefly explain on Pyruvate Dehydrogenase Complex (PDC) and its control, Reactions of TCA cycle or CAC and Amphibolic nature of TCA cycle. (assignmentpoint.com)
- Pyruvate metabolism and the citric acid (TCA) cycle together link the processes of energy metabolism in a human cell with one another and with key biosynthetic reactions. (reactome.org)
- One conclusion is that theories that involve the organization of complex, small-molecule metabolic cycles such as the reductive citric acid cycle on mineral surfaces make unreasonable assumptions about the catalytic properties of minerals and the ability of minerals to organize sequences of disparate reactions. (pnas.org)
- The exact nature of the prior form of self-organization that is postulated differs from one scenario to the next, but all scenarios have one feature in common: a self-organized cycle or network of chemical reactions that does not depend directly or indirectly on a genetic polymer ( 8 - 11 ). (pnas.org)
- Wächtershäuser argues that they were supplied via a complex cycle of nonenzymatic chemical reactions that took place on the surface of iron sulfide minerals, perhaps including pyrites, FeS 2 ( 9 ). (pnas.org)
- Enzymes, proteins, electron carriers, and pumps that play roles in glycolysis, the citric acid cycle, and the electron transport chain tend to catalyze non-reversible reactions. (oercommons.org)
- The citric acid cycle is a series of chemical reactions that removes high-energy electrons and uses them in the electron transport chain to generate ATP. (opentextbooks.org.hk)
- After its transfer to the four-carbon molecule oxaloacetate, the acetyl group enters a series of reactions called the citric acid cycle . (nih.gov)
- The eight steps of the cycle are a series of chemical reactions that produces two carbon dioxide molecules, one ATP molecule (or an equivalent), and reduced forms (NADH and FADH 2 ) of NAD + and FAD + , important coenzymes in the cell. (opentextbc.ca)
- K a is acid constant for equilibrium reactions. (bartleby.com)
- Most cells will then carry out further reactions to 'repay' the used NAD+ and produce a final product of ethanol or lactic acid. (wikipedia.org)
- The final breakdown is accomplished by a series of reactions known as the KREBS CITRIC ACID CYCLE. (angelfire.com)
- a series of reactions, beginning and ending with oxaloacetic acid, during the course of which a two-carbon fragment is completely oxidized to carbon dioxide and water with the production of 12 high-energy phosphate bonds. (thefreedictionary.com)
- The name of this metabolic pathway is derived from citric acid (a type of tricarboxylic acid ) that is consumed and then regenerated by this sequence of reactions to complete the cycle. (wn.com)
- In biochemistry , it is an intermediate in the citric acid cycle , which occurs in the metabolism of all aerobic organisms . (wikipedia.org)
- In biochemistry, it is important as an intermediate in the citric acid cycle and therefore occurs in the metabolism of almost all living things. (kroon-partners.nl)
- The citric acid cycle is a key metabolic pathway that connects carbohydrate, fat, and protein metabolism. (wikipedia.org)
- We then focused on reaction types that are fundamental to modern TCA cycle metabolism: aldol addition and oxidative decarboxylation. (nature.com)
- In addition to serving as the primary pathway in oxidative metabolism for the degradation of nutrient molecules, ultimately to give rise to ATP through electron transport, the citric acid cycle is a major source of precursors for the synthesis of biological molecules. (wikipremed.com)
- Citric acid forms a vital part of human metabolism and is present in every human body. (reference.com)
- Citric acid is used in the process of metabolism in the humans, animals and plants. (creationwiki.org)
- The citric acid cycle is referred to as the "hub of the intermediate metabolism" because it has a central role for a lot of metabolic pathways. (lecturio.com)
- In addition to its role in energy generation, the citric acid cycle is a source of carbon skeletons for amino acid metabolism and other biosynthetic processes. (reactome.org)
- One such process included here is the interconversion of 2-hydroxyglutarate, probably derived from porphyrin and amino acid metabolism, and 2-oxoglutarate (alpha-ketoglutarate), a citric acid cycle intermediate. (reactome.org)
- Nakada, D., Saunders, T. L. & Morrison, S. J. Lkb1 regulates cell cycle and energy metabolism in haematopoietic stem cells. (nature.com)
- Central pathways of metabolism: How the body produces energy from the energy-containing nutrients using the tricarboxylic acid cycle. (thefreedictionary.com)
- it is a major route for removal of the ammonia produced in the metabolism of amino acids in the liver and kidney. (thefreedictionary.com)
- These results indicate that simpler versions of metabolic cycles could have emerged under potential prebiotic conditions, laying the foundation for the appearance of more sophisticated metabolic pathways once control by (polymeric) catalysts became available. (nature.com)
- The metabolic pathways include glycolysis and the citric acid cycle. (study.com)
- Describe the main anaplerotic pathways that permit replenishment of citric acid cycle intermediates, and how the withdrawal of oxaloacetate for gluconeogenesis is controlled. (mhmedical.com)
- If lactate or propionate were added, malate and citrate accumulated indicating utilization of anaplerotic pathways for the citric acid cycle. (mysciencework.com)
- The Important Role of the Citric Acid Cycle in Plants The TCA cycle is a central metabolic hub necessary for ATP production and for providing precursors used in many biosynthetic pathways. (kroon-partners.nl)
- I previously wrote METHYLATION CYCLE, GENETICS, B VITAMINS in which I considered in-depth how the Methylation Cycle functions, how genetics affect metabolic pathways, and how B vitamins (including vitamin B12, folate, vitamin B6, and vitamin B2) are used in Methylation Cycle pathways. (integratedhealthblog.com)
- Acetyl CoA can enter the citric acid cycle, a major source of reducing equivalents used to synthesize ATP, or enter biosynthetic pathways. (reactome.org)
- A cell does not need the maximum amount of ATP that it can make all the time: At times, the cell needs to shunt some of the intermediates to pathways for amino acid, protein, glycogen, lipid, and nucleic acid production. (oercommons.org)
- You have just read about two pathways in glucose catabolism-glycolysis and the citric acid cycle-that generate ATP. (opentextbc.ca)
Enzymes of the citri1
- By acting as the first stage of cellular respiration, the generation of high energy electrons from the citric acid cycle, in turn, are used in oxidative phosphorylation to reduce O 2 , generate proton gradient, and, later, the synthesis of ATP. (wikibooks.org)
- The two phases of cellular respiration are: 1) Glycolysis and 2) the Citric Acid Cycle. (encognitive.com)
- The regulation of the cycle is by cellular needs of ATP. (biochemden.com)
- The two major products of Citric Acid Cycle are: NADH (the reduced form of nicotinamide adenine dinucleotide) and FADH2 (the reduced form of flavin adenine dinucleotide). (org.in)
- The NADH and FADH2 produced by the citric acid cycle in the matrix release a proton and electron to regenerate NAD+ and FAD+. (bionity.com)
Regulation of the Citri1
- The market for citric acid for application in the pharmaceutical and personal care sectors is emerging with substantial opportunities and is projected to grow at a competitive CAGR from 2015 to 2020. (marketsandmarkets.com)
- The global market for citric acid is projected to grow at competitive CAGRs of 5.5% and 5.2%, in terms of value and volume respectively, from 2015 to 2020. (bharatbook.com)
Market for citric acid1
Uses citric acid2
- Explain how the citric acid cycle provides both a route for catabolism of amino acids and also a route for their synthesis. (mhmedical.com)
- Dec 06, 2008· Best Answer: The citric acid cycle forms the electron carriers which drive the synthesis of ATP. (org.in)
- The cycle is also central to most of the synthesis of biomolecules in you. (docpelletier.com)
- Stanley Miller's synthesis of the amino acids by sparking a reducing atmosphere ( 2 ) was the paradigm for prebiotic synthesis for many years, so at first, it was natural to suppose that similar methods would meet with equal success in the nucleotide field. (pnas.org)
Produce citric acid2
- Metabolomic and mass isotopomer analysis of liver gluconeogenesis and citric acid cycle: II. (labome.org)
- Modifications of citric acid cycle activity and gluconeogenesis in streptozotocin-induced diabetes and effects of metformin. (diabetesjournals.org)
- It also has a central role in gluconeogenesis, lipogenesis, and interconversion of amino acids. (mhmedical.com)
- It is a colorless translucent crystalline acid that is a monohydrate and a anhydrous material. (creationwiki.org)
- Because of its high solubility, citric acid is preferred in its anhydrous crystal form by the food industry, where it is widely used to add acidity to products. (reference.com)
- The anhydrous crystals are much more stable and can be stored for long-term, industrial use without fear of the acid melting away due to contact with moisture in the air. (reference.com)
- The report provides a detailed analysis of the citric acid market, which is segmented into two major forms- anhydrous citric acid and liquid citric acid. (marketsandmarkets.com)
- Anhydrous citric acid is the most preferable form, owing to its ease of transportation and longer shelf life. (marketsandmarkets.com)
- Its complex is composed of members of a family of homologous complexes which include citric acid cycle enzyme a-ketoglutarate dehydrogenase complex. (wikibooks.org)
- FADH 2 is covalently attached to succinate dehydrogenase, an enzyme functioning both in the TCA cycle and the mitochondrial electron transfer chain in oxidative phosphorylation. (chemeurope.com)
- Citric acid undergoes a series of enzyme-catalyzed conversions. (boekhandeldeoorsprong.nl)
- Oxoglutarate dehydrogenase (aka α-ketoglutarate dehydrogenase ) is an enzyme complex most commonly known for its role in the citric acid cycle . (wikidoc.org)
Soluble in water3
- Most of the energy made available by the oxidative steps of the cycle is transferred as energy-rich electrons to NAD+, forming NADH. (wikipedia.org)
- The Citric Acid Cycle has eight-steps. (wikibooks.org)
- The citric acid cycle consists of a series of steps used to catalyze products following the oxidation of pyruvate. (coursehero.com)
- The citric acid cycle involves the following eight steps to catalyze products following the oxidation of pyruvate. (coursehero.com)
- However, nucleotides are intrinsically more complicated than amino acids, and it is by no means obvious that they can be obtained in a few simple steps under prebiotic conditions. (pnas.org)
High energy electrons1
- This is because oxygen is needed later, during the electron transport chain, which creates the ATP and NADH used to drive this cycle. (coursehero.com)
- While direct substrate phosphorylation does occur to an extent in the citric acid cycle, the processes of the electron transport chain yield a great deal of energy, forming most of the ATPs per glucose in aerobic respiration. (wikipremed.com)
- An integral part of the citric acid cycle is the electron transport system. (encognitive.com)
- There are three separate stages of glucose oxidation: glycolysis, the citric acid cycle, and the electron transport system. (wisegeek.com)
- GLYCOLYSIS , KREBS or CITRIC ACID CYCLE , and OXIDATIVE PHOSPHORYLATION (ELECTRON TRANSPORT CHAIN). (angelfire.com)
- The acetyl CoA is condensed with Oxaloacetic acid (OAA) it gives Tricarboxylic acid Citric acid. (biochemden.com)
- Malate is dehydrogenated into Oxaloacetic acid by using NAD as a proton acceptor. (biochemden.com)
- Oxaloacetic acid. (org.in)
- In the end, it regenerates oxaloacetic acid to continue the citric acid cycle. (bionity.com)