The protein components of enzyme complexes (HOLOENZYMES). An apoenzyme is the holoenzyme minus any cofactors (ENZYME COFACTORS) or prosthetic groups required for the enzymatic function.
The protein components of a number of complexes, such as enzymes (APOENZYMES), ferritin (APOFERRITINS), or lipoproteins (APOLIPOPROTEINS).
This is the active form of VITAMIN B 6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (PYRIDOXAMINE).
An enzyme that catalyzes the conversion of methylmalonyl-CoA to succinyl-CoA by transfer of the carbonyl group. It requires a cobamide coenzyme. A block in this enzymatic conversion leads to the metabolic disease, methylmalonic aciduria. EC
A condensation product of riboflavin and adenosine diphosphate. The coenzyme of various aerobic dehydrogenases, e.g., D-amino acid oxidase and L-amino acid oxidase. (Lehninger, Principles of Biochemistry, 1982, p972)
The 4-carboxyaldehyde form of VITAMIN B 6 which is converted to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid.
D-Amino-Acid Oxidase is an enzyme that catalyzes the oxidative deamination of D-amino acids to their corresponding α-keto acids, ammonia, and hydrogen peroxide, playing a crucial role in the metabolism of non-proteinogenic D-amino acids.
The rate dynamics in chemical or physical systems.
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
The 4-aminomethyl form of VITAMIN B 6. During transamination of amino acids, PYRIDOXAL PHOSPHATE is transiently converted into pyridoxamine phosphate.
Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Small molecules that are required for the catalytic function of ENZYMES. Many VITAMINS are coenzymes.
Enzymes of the transferase class that catalyze the conversion of L-aspartate and 2-ketoglutarate to oxaloacetate and L-glutamate. EC
A flavoprotein containing oxidoreductase that catalyzes the reduction of lipoamide by NADH to yield dihydrolipoamide and NAD+. The enzyme is a component of several MULTIENZYME COMPLEXES.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.
A pyrrolo-quinoline having two adjacent keto-groups at the 4 and 5 positions and three acidic carboxyl groups. It is a coenzyme of some DEHYDROGENASES.
An enzyme that catalyzes the conversion of L-tryptophan and water to indole, pyruvate, and ammonia. It is a pyridoxal-phosphate protein, requiring K+. It also catalyzes 2,3-elimination and beta-replacement reactions of some indole-substituted tryptophan analogs of L-cysteine, L-serine, and other 3-substituted amino acids. (From Enzyme Nomenclature, 1992) EC
Cobamides are a class of compounds that function as cofactors in various enzymatic reactions, containing a corrin ring similar to vitamin B12, but with different substituents on the benzimidazole moiety, and can be found in certain bacteria and archaea.
An enzyme that catalyzes the dehydration of 1,2-propanediol to propionaldehyde. EC
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Measurement of the intensity and quality of fluorescence.
A pyridoxal-phosphate protein that catalyzes the conversion of L-tyrosine to tyramine and carbon dioxide. The bacterial enzyme also acts on 3-hydroxytyrosine and, more slowly, on 3-hydroxyphenylalanine. (From Enzyme Nomenclature, 1992) EC
An enzyme of the transferase class that catalyzes the conversion of sedoheptulose 7-phosphate and D-glyceraldehyde 3-phosphate to D-ribose 5-phosphate and D-xylulose 5-phosphate in the PENTOSE PHOSPHATE PATHWAY. (Dorland, 27th ed) EC
A pyridoxal phosphate enzyme that catalyzes the reaction of glycine and 5,10-methylene-tetrahydrofolate to form serine. It also catalyzes the reaction of glycine with acetaldehyde to form L-threonine. EC
Pyruvate oxidase is an enzyme complex located within the mitochondrial matrix that catalyzes the oxidative decarboxylation of pyruvate into acetyl-CoA, thereby linking glycolysis to the citric acid cycle and playing a crucial role in cellular energy production.
The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
The coenzyme form of Vitamin B1 present in many animal tissues. It is a required intermediate in the PYRUVATE DEHYDROGENASE COMPLEX and the KETOGLUTARATE DEHYDROGENASE COMPLEX.
A trace element that is a component of vitamin B12. It has the atomic symbol Co, atomic number 27, and atomic weight 58.93. It is used in nuclear weapons, alloys, and pigments. Deficiency in animals leads to anemia; its excess in humans can lead to erythrocytosis.
Catalyzes the decarboxylation of an alpha keto acid to an aldehyde and carbon dioxide. Thiamine pyrophosphate is an essential cofactor. In lower organisms, which ferment glucose to ethanol and carbon dioxide, the enzyme irreversibly decarboxylates pyruvate to acetaldehyde. EC
A standard reagent for the determination of reactive sulfhydryl groups by absorbance measurements. It is used primarily for the determination of sulfhydryl and disulfide groups in proteins. The color produced is due to the formation of a thio anion, 3-carboxyl-4-nitrothiophenolate.
An enzyme that catalyzes the deamination of ethanolamine to acetaldehyde. EC
The extent to which an enzyme retains its structural conformation or its activity when subjected to storage, isolation, and purification or various other physical or chemical manipulations, including proteolytic enzymes and heat.
A class of enzymes that catalyze the cleavage of C-C, C-O, and C-N, and other bonds by other means than by hydrolysis or oxidation. (Enzyme Nomenclature, 1992) EC 4.
D-Glucose:1-oxidoreductases. Catalyzes the oxidation of D-glucose to D-glucono-gamma-lactone and reduced acceptor. Any acceptor except molecular oxygen is permitted. Includes EC; EC; EC and EC
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)
A dioxygenase with specificity for the oxidation of the indoleamine ring of TRYPTOPHAN. It is a LIVER-specific enzyme that is the first and rate limiting enzyme in the kynurenine pathway of TRYPTOPHAN catabolism.
A PYRIDOXAL-phosphate containing enzyme that catalyzes the dehydration and deamination of L-serine to form pyruvate. This enzyme was formerly listed as EC
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)
A pyridoxal phosphate enzyme that catalyzes the formation of glutamate gamma-semialdehyde and an L-amino acid from L-ornithine and a 2-keto-acid. EC
A glucose dehydrogenase that catalyzes the oxidation of beta-D-glucose to form D-glucono-1,5-lactone, using NAD as well as NADP as a coenzyme.
An enzyme of the oxidoreductase class that catalyzes the conversion of beta-D-glucose and oxygen to D-glucono-1,5-lactone and peroxide. It is a flavoprotein, highly specific for beta-D-glucose. The enzyme is produced by Penicillium notatum and other fungi and has antibacterial activity in the presence of glucose and oxygen. It is used to estimate glucose concentration in blood or urine samples through the formation of colored dyes by the hydrogen peroxide produced in the reaction. (From Enzyme Nomenclature, 1992) EC
Catalytically active enzymes that are formed by the combination of an apoenzyme (APOENZYMES) and its appropriate cofactors and prosthetic groups.
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Compounds containing the -SH radical.
A subclass of enzymes of the transferase class that catalyze the transfer of an amino group from a donor (generally an amino acid) to an acceptor (generally a 2-keto acid). Most of these enzymes are pyridoxyl phosphate proteins. (Dorland, 28th ed) EC 2.6.1.
Enzymes that catalyze the breakage of a carbon-oxygen bond leading to unsaturated products via the removal of water. EC 4.2.1.
The 4-methanol form of VITAMIN B 6 which is converted to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. Although pyridoxine and Vitamin B 6 are still frequently used as synonyms, especially by medical researchers, this practice is erroneous and sometimes misleading (EE Snell; Ann NY Acad Sci, vol 585 pg 1, 1990).
Derivatives of the dimethylisoalloxazine (7,8-dimethylbenzo[g]pteridine-2,4(3H,10H)-dione) skeleton. Flavin derivatives serve an electron transfer function as ENZYME COFACTORS in FLAVOPROTEINS.
A class of enzymes that catalyze geometric or structural changes within a molecule to form a single product. The reactions do not involve a net change in the concentrations of compounds other than the substrate and the product.(from Dorland, 28th ed) EC 5.
Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.
The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
An enzyme that catalyzes the conversion of urea and water to carbon dioxide and ammonia. EC
The sum of the weight of all the atoms in a molecule.
A coenzyme for a number of oxidative enzymes including NADH DEHYDROGENASE. It is the principal form in which RIBOFLAVIN is found in cells and tissues.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)
Salts of hydrobromic acid, HBr, with the bromine atom in the 1- oxidation state. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Positively charged atoms, radicals or groups of atoms with a valence of plus 2, which travel to the cathode or negative pole during electrolysis.
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).
Enzymes that catalyze the dehydrogenation of GLYCERALDEHYDE 3-PHOSPHATE. Several types of glyceraldehyde-3-phosphate-dehydrogenase exist including phosphorylating and non-phosphorylating varieties and ones that transfer hydrogen to NADP and ones that transfer hydrogen to NAD.
Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.
A family of iminourea derivatives. The parent compound has been isolated from mushrooms, corn germ, rice hulls, mussels, earthworms, and turnip juice. Derivatives may have antiviral and antifungal properties.
A class of organic compounds which contain an anilino (phenylamino) group linked to a salt or ester of naphthalenesulfonic acid. They are frequently used as fluorescent dyes and sulfhydryl reagents.
A process of selective diffusion through a membrane. It is usually used to separate low-molecular-weight solutes which diffuse through the membrane from the colloidal and high-molecular-weight solutes which do not. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A malonic acid derivative which is a vital intermediate in the metabolism of fat and protein. Abnormalities in methylmalonic acid metabolism lead to methylmalonic aciduria. This metabolic disease is attributed to a block in the enzymatic conversion of methylmalonyl CoA to succinyl CoA.
The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.

Comparison of the backbone dynamics of the apo- and holo-carboxy-terminal domain of the biotin carboxyl carrier subunit of Escherichia coli acetyl-CoA carboxylase. (1/550)

The biotin carboxyl carrier protein (BCCP) is a subunit of acetyl-CoA carboxylase, a biotin-dependent enzyme that catalyzes the first committed step of fatty acid biosynthesis. In its functional cycle, this protein engages in heterologous protein-protein interactions with three distinct partners, depending on its state of post-translational modification. Apo-BCCP interacts specifically with the biotin holoenzyme synthetase, BirA, which results in the post-translational attachment of biotin to a single lysine residue on BCCP. Holo-BCCP then interacts with the biotin carboxylase subunit of acetyl-CoA carboxylase, which leads to the addition of the carboxylate group of bicarbonate to biotin. Finally, the carboxy-biotinylated form of BCCP interacts with transcarboxylase in the transfer of the carboxylate to acetyl-CoA to form malonyl-CoA. The determinants of protein-protein interaction specificity in this system are unknown. The NMR solution structure of the unbiotinylated form of an 87 residue C-terminal domain fragment (residue 70-156) of BCCP (holoBCCP87) and the crystal structure of the biotinylated form of a C-terminal fragment (residue 77-156) of BCCP from Escherichia coli acetyl-CoA carboxylase have previously been determined. Comparative analysis of these structures provided evidence for small, localized conformational changes in the biotin-binding region upon biotinylation of the protein. These structural changes may be important for regulating specific protein-protein interactions. Since the dynamic properties of proteins are correlated with local structural environments, we have determined the relaxation parameters of the backbone 15N nuclear spins of holoBCCP87, and compared these with the data obtained for the apo protein. The results indicate that upon biotinylation, the inherent mobility of the biotin-binding region and the protruding thumb, with which the biotin group interacts in the holo protein, are significantly reduced.  (+info)

Dietary thiamin level influences levels of its diphosphate form and thiamin-dependent enzymic activities of rat liver. (2/550)

This study was prompted by our incomplete understanding of the mechanism responsible for the clinical benefits of pharmacological doses of thiamin in some patients with maple syrup urine disease (MSUD) and the question of whether thiamin diphosphate (TDP), a potent inhibitor of the activity of the protein kinase that phosphorylates and inactivates the isolated branched-chain alpha-ketoacid dehydrogenase (BCKDH) complex, affects the activity state of the complex. Rats were fed a chemically-defined diet containing graded levels of thiamin (0, 0.275, 0.55, 5.5, and 55 mg thiamin/kg diet). Maximal weight gain was attained over a 3-wk period only in rats fed diets with 5.5 and 55 mg thiamin/kg. Feeding rats the thiamin-free diet for just 2 d caused loss of nearly half of the TDP from liver mitochondria. Three more days caused over 70% loss, an additional 3 wk, over 90%. Starvation for 2 d had no effect, suggesting a mechanism for conservation of TDP in this nutritional state. Mitochondrial TDP was higher in rats fed pharmacological amounts of thiamin (55 mg thiamin/kg diet) than in rats fed adequate thiamin for maximal growth. Varying dietary thiamin had marked but opposite effects on the activities of alpha-ketoglutarate dehydrogenase (alpha-KGDH) and BCKDH. Thiamin deficiency decreased alpha-KGDH activity, increased BCKDH activity, and increased the proportion of BCKDH in the active, dephosphorylated, state. Excess dietary thiamin had the opposite effects. TDP appears to be more tightly associated with alpha-KGDH than BCKDH in thiamin-deficient rats, perhaps denoting retention of alpha-KGDH activity at the expense of BCKDH activity. Thus, thiamin deficiency and excess cause large changes in mitochondrial TDP levels that have a major influence on the activities of the keto acid dehydrogenase complexes.  (+info)

Structural characterization of l-aspartate oxidase and identification of an interdomain loop by limited proteolysis. (3/550)

l-Aspartate oxidase is the first enzyme in the de novo biosynthesis of pyridinic coenzymes in facultative aerobic organisms. The enzyme is FAD dependent and it shares common features with both the oxidase and the fumarate reductase classes of flavoproteins. In this report we focused our attention on the supersecondary structure of the molecule by means of limited proteolysis studies. Moreover the polymerization state of the protein at different pH and the interactions with NAD and its analogues are described. The results suggest that l-aspartate oxidase is a monomer at pH values lower than 4.5 and a dimer at pH values higher than 6.5. The protein is organized in two major domains connected by a flexible loop located in the 120-140 region. The data obtained by limited proteolysis of the holo and the apo form in the presence and in the absence of substrates (fumarate and menadione), inhibitors (succinate) and NAD allows the proposition that both domains are involved in the binding of the flavin coenzyme. Moreover the data reported in this manuscript suggest that NAD inhibits l-aspartate oxidase activity by competing with the flavin for the binding to the enzyme.  (+info)

Effects of divalent metal ions on the activity and conformation of native and 3-fluorotyrosine-PvuII endonucleases. (4/550)

The activities of restriction enzymes are important examples of Mg(II)-dependent hydrolysis of DNA. While a number of crystallographic studies of enzyme-DNA complexes have also involved metal ions, there have been no solution studies exploring the relationship between enzyme conformation and metal-ion binding in restriction enzymes. Using PvuII restriction endonuclease as a model system, we have successfully developed biosynthetic fluorination and NMR spectroscopy as a solution probe of restriction-enzyme conformation. The utility of this method is demonstrated with a study of metal-ion binding by PvuII endonuclease. Replacement of 74% (+/- 10%) of the Tyr residues in PvuII endonuclease by 3-fluorotyrosine produces an enzyme with Mg(II)-supported specific activity and sequence specificity that is indistinguishable from that of the native enzyme. Mn(II) supports residual activity of both the native and fluorinated enzymes; Ca(II) does not support activity in either enzyme, a result consistent with previous studies. 1H- and 19F-NMR spectroscopic studies reveal that while Mg(II) does not alter the enzyme conformation, the paramagnetic Mn(II) produces both short-range spectral broadening and longer range changes in chemical shift. Most interestingly, Ca(II) binding perturbs a larger number of different resonances than Mn(II). Coupled with earlier mutagenesis studies that place Ca(II) in the active site [Nastri, H. G., Evans, P.D., Walker, I.H. & Riggs, P.D. (1997) J. Biol. Chem. 272, 25761-25767], these data suggest that the enzyme makes conformational adjustments to accommodate the distinct geometric preferences of Ca(II) and may play a role in the inability of this metal ion to support activity in restriction enzymes.  (+info)

The aconitase of yeast. V. The reconstitution of yeast aconitase. (5/550)

The apoenzyme of yeast aconitase [EC] was prepared by treatment of yeast aconitase with sodium mersalyl, followed by passage by passage of the reaction mixture through a column of Dowex A-1 and gel filtration on Sephadex G-25. The apoenzyme had no aconitase activity, but the active enzyme could be reconstituted by treatment of the apoenzyme with ferrous ions and sodium sulfide in the presence of 2-mercapto-ethanol. The reconstituted active enzyme was isolated by DEAE-Sephadex A-50 column chromatography and Sephadex G-100 gel filtration from the reaction mixture. The reconstituted enzyme was identical with the original untreated enzyme in terms of specific activity, iron content and spectral characteristics, but not in terms of labile sulfur content. A significant difference in visible spectra between the holo- and apoenzymes appeared to be due to the difference in iron and labile sulfur contents between the two proteins.  (+info)

Rapid PCR test for discriminating between Candida albicans and Candida dubliniensis isolates using primers derived from the pH-regulated PHR1 and PHR2 genes of C. albicans. (6/550)

The development of a satisfactory means to reliably distinguish between the two closely related species Candida albicans and Candida dubliniensis in the clinical mycology laboratory has proved difficult because these two species are phenotypically so similar. In this study, we have detected homologues of the pH-regulated C. albicans PHR1 and PHR2 genes in C. dubliniensis. Restriction fragment length polymorphism analysis suggests that there are significant sequence differences between the genes of the two species. In order to exploit this apparent difference, oligonucleotide primers based on the coding sequence of the C. albicans PHR1 structural gene were designed and used in PCR experiments. Use of these primers with C. albicans template DNA from 17 strains yielded a predicted 1.6-kb product, while C. dubliniensis template DNA from 19 strains yielded no product. We therefore propose that PCR using these primers is a rapid and reliable means of distinguishing the two germ tube- and chlamydospore-producing species C. albicans and C. dubliniensis.  (+info)

A novel 35 kDa frog liver acid metallophosphatase. (7/550)

The lower molecular weight (35 kDa) acid phosphatase from the frog (Rana esculenta) liver is a glycometalloenzyme susceptible to activation by reducing agents and displaying tartrate and fluoride resistance. Metal chelators (EDTA, 1,10-phenanthroline) inactivate the enzyme reversibly in a time- and temperature-dependent manner. The apoenzyme is reactivated by divalent transition metal cations, i. e. cobalt, zinc, ferrous, manganese, cadmium and nickel to 130%, 75%, 63%, 62%, 55% and 34% of the original activity, respectively. Magnesium, calcium, cupric and ferric ions were shown to be ineffective in this process. Metal analysis by the emission spectrometry method (inductively coupled plasma-atomic emission spectrometry) revealed the presence of zinc, iron and magnesium. The time course of the apoenzyme reactivation, the stabilization effect and the relatively high resistance to oxidizing conditions indicate that the zinc ion is crucial for the enzyme activity. The presence of iron was additionally confirmed by the visible absorption spectrum of the enzyme with a shoulder at 417 nm and by the electron paramagnetic resonance line of high spin iron(III) with geff of 2.4. The active center containing only zinc or both zinc and iron ions is proposed. The frog liver lower molecular weight acid phosphatase is a novel metallophosphatase of lower vertebrate origin, distinct from the mammalian tartrate-resistant, purple acid phosphatases.  (+info)

Purification of beef kidney D-aspartate oxidase overexpressed in Escherichia coli and characterization of its redox potentials and oxidative activity towards agonists and antagonists of excitatory amino acid receptors. (8/550)

The flavoenzyme d-aspartate oxidase from beef kidney (DASPO, EC 1.4. 3.1) has been overexpressed in Escherichia coli. A purification procedure, faster than the one used for the enzyme from the natural source (bDASPO), has been set up yielding about 2 mg of pure recombinant protein (rDASPO) per each gram of wet E. coli paste. rDASPO has been shown to possess the same general biochemical properties of bDASPO, except that the former contains only FAD, while the latter is a mixture of two forms, one active containing FAD and one inactive containing 6-OH-FAD (9-20% depending on the preparation). This results in a slightly higher specific activity (about 15%) for rDASPO compared to bDASPO and in facilitated procedures for apoprotein preparation and reconstitution. Redox potentials of -97 mV and -157 mV were determined for free and l-(+)-tartrate complexed DASPO, respectively, in 0.1 M KPi, pH 7.0, 25 degrees C. The large positive shift in the redox potential of the coenzyme compared to free FAD (-207 mV) is in agreement with similar results obtained with other flavooxidases. rDASPO has been used to assess a possible oxidative activity of the enzyme towards a number of compounds used as agonists or antagonists of neurotransmitters, including d-aspartatic acid, d-glutamic acid, N-methyl-d-aspartic acid, d,l-cysteic acid, d-homocysteic acid, d, l-2-amino-3-phosphonopropanoic acid, d-alpha-aminoadipic acid, d-aspartic acid-beta-hydroxamate, glycyl-d-aspartic acid and cis-2, 3-piperidine dicarboxylic acid. Kinetic parameters for each substrate in 50 mM KPi, pH 7.4, 25 degrees C are reported.  (+info)

An apoenzyme is the protein component of an enzyme that is responsible for its catalytic activity. It combines with a cofactor, which can be either an organic or inorganic non-protein molecule, to form the active enzyme. The cofactor can be a metal ion or a small organic molecule called a coenzyme.

The term "apoenzyme" is used to describe the protein portion of an enzyme after it has lost its cofactor. When the apoenzyme combines with the cofactor, the active holoenzyme is formed, which is capable of carrying out the specific biochemical reaction for which the enzyme is responsible.

In some cases, the loss of a cofactor can result in the complete loss of enzymatic activity, while in other cases, the apoenzyme may retain some residual activity. The relationship between an apoenzyme and its cofactor is specific, meaning that each cofactor typically only binds to and activates one particular type of apoenzyme.

Apoproteins are the protein components of lipoprotein complexes, which are responsible for transporting fat molecules, such as cholesterol and triglycerides, throughout the body. Apoproteins play a crucial role in the metabolism of lipids by acting as recognition signals that allow lipoproteins to interact with specific receptors on cell surfaces.

There are several different types of apoproteins, each with distinct functions. For example, apolipoprotein A-1 (apoA-1) is the major protein component of high-density lipoproteins (HDL), which are responsible for transporting excess cholesterol from tissues to the liver for excretion. Apolipoprotein B (apoB) is a large apoprotein found in low-density lipoproteins (LDL), very low-density lipoproteins (VLDL), and lipoprotein(a). ApoB plays a critical role in the assembly and secretion of VLDL from the liver, and it also mediates the uptake of LDL by cells.

Abnormalities in apoprotein levels or function can contribute to the development of various diseases, including cardiovascular disease, diabetes, and Alzheimer's disease. Therefore, measuring apoprotein levels in the blood can provide valuable information for diagnosing and monitoring these conditions.

Pyridoxal phosphate (PLP) is the active form of vitamin B6 and functions as a cofactor in various enzymatic reactions in the human body. It plays a crucial role in the metabolism of amino acids, carbohydrates, lipids, and neurotransmitters. Pyridoxal phosphate is involved in more than 140 different enzyme-catalyzed reactions, making it one of the most versatile cofactors in human biochemistry.

As a cofactor, pyridoxal phosphate helps enzymes carry out their functions by facilitating chemical transformations in substrates (the molecules on which enzymes act). In particular, PLP is essential for transamination, decarboxylation, racemization, and elimination reactions involving amino acids. These processes are vital for the synthesis and degradation of amino acids, neurotransmitters, hemoglobin, and other crucial molecules in the body.

Pyridoxal phosphate is formed from the conversion of pyridoxal (a form of vitamin B6) by the enzyme pyridoxal kinase, using ATP as a phosphate donor. The human body obtains vitamin B6 through dietary sources such as whole grains, legumes, vegetables, nuts, and animal products like poultry, fish, and pork. It is essential to maintain adequate levels of pyridoxal phosphate for optimal enzymatic function and overall health.

Methylmalonyl-CoA mutase is a mitochondrial enzyme that plays a crucial role in the metabolism of certain amino acids and fatty acids. Specifically, it catalyzes the isomerization of methylmalonyl-CoA to succinyl-CoA, which is an important step in the catabolic pathways of valine, isoleucine, threonine, methionine, odd-chain fatty acids, and cholesterol.

The enzyme requires a cofactor called adenosylcobalamin (vitamin B12) for its activity. In the absence of this cofactor or due to mutations in the gene encoding the enzyme, methylmalonyl-CoA mutase deficiency can occur, leading to the accumulation of methylmalonic acid and other toxic metabolites, which can cause a range of symptoms including vomiting, dehydration, lethargy, hypotonia, developmental delay, and metabolic acidosis. This condition is typically inherited in an autosomal recessive manner and can be diagnosed through biochemical tests and genetic analysis.

Flavin-Adenine Dinucleotide (FAD) is a coenzyme that plays a crucial role in various metabolic processes, particularly in the electron transport chain where it functions as an electron carrier in oxidation-reduction reactions. FAD is composed of a flavin moiety, riboflavin or vitamin B2, and adenine dinucleotide. It can exist in two forms: an oxidized form (FAD) and a reduced form (FADH2). The reduction of FAD to FADH2 involves the gain of two electrons and two protons, which is accompanied by a significant conformational change that allows FADH2 to donate its electrons to subsequent components in the electron transport chain, ultimately leading to the production of ATP, the main energy currency of the cell.

Pyridoxal is a form of vitamin B6, specifically the alcohol form of pyridoxine. It is a cofactor for many enzymes involved in protein metabolism and synthesis of neurotransmitters. Pyridoxal can be converted to its active form, pyridoxal 5'-phosphate (PLP), which serves as a coenzyme in various biochemical reactions, including transamination, decarboxylation, and racemization/elimination reactions. Deficiency in vitamin B6 can lead to neurological disorders and impaired synthesis of amino acids and neurotransmitters.

D-amino-acid oxidase (DAAO) is an enzyme that catalyzes the oxidative deamination of D-amino acids to their corresponding α-keto acids, ammonia, and hydrogen peroxide. This enzyme plays a crucial role in the metabolism of D-amino acids in various organisms, including humans. In humans, DAAO is primarily expressed in the brain and contributes to the regulation of neurotransmitter levels and other physiological processes. Genetic variations and dysregulation of DAAO have been implicated in several neurological disorders, such as schizophrenia and bipolar disorder.

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

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

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

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

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

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

Spectrophotometry is a technical analytical method used in the field of medicine and science to measure the amount of light absorbed or transmitted by a substance at specific wavelengths. This technique involves the use of a spectrophotometer, an instrument that measures the intensity of light as it passes through a sample.

In medical applications, spectrophotometry is often used in laboratory settings to analyze various biological samples such as blood, urine, and tissues. For example, it can be used to measure the concentration of specific chemicals or compounds in a sample by measuring the amount of light that is absorbed or transmitted at specific wavelengths.

In addition, spectrophotometry can also be used to assess the properties of biological tissues, such as their optical density and thickness. This information can be useful in the diagnosis and treatment of various medical conditions, including skin disorders, eye diseases, and cancer.

Overall, spectrophotometry is a valuable tool for medical professionals and researchers seeking to understand the composition and properties of various biological samples and tissues.

Pyridoxamine is a form of vitamin B6, which is a water-soluble vitamin that plays an essential role in the body's protein metabolism, neurotransmitter synthesis, and hemoglobin production. Pyridoxamine is a specific chemical compound that is a derivative of pyridoxine, another form of vitamin B6.

Pyridoxamine functions as a cofactor for various enzymes involved in the metabolism of amino acids, the building blocks of proteins. It helps to convert harmful homocysteine into the essential amino acid methionine, which is important for maintaining normal levels of homocysteine and supporting cardiovascular health.

Pyridoxamine has been studied for its potential role in treating or preventing certain medical conditions, such as diabetic nephropathy and neurodegenerative diseases, due to its antioxidant properties and ability to protect against protein glycation, a process that can damage tissues and contribute to aging and disease. However, more research is needed to establish its safety and efficacy for these uses.

Spectrophotometry, Ultraviolet (UV-Vis) is a type of spectrophotometry that measures how much ultraviolet (UV) and visible light is absorbed or transmitted by a sample. It uses a device called a spectrophotometer to measure the intensity of light at different wavelengths as it passes through a sample. The resulting data can be used to determine the concentration of specific components within the sample, identify unknown substances, or evaluate the physical and chemical properties of materials.

UV-Vis spectroscopy is widely used in various fields such as chemistry, biology, pharmaceuticals, and environmental science. It can detect a wide range of substances including organic compounds, metal ions, proteins, nucleic acids, and dyes. The technique is non-destructive, meaning that the sample remains unchanged after the measurement.

In UV-Vis spectroscopy, the sample is placed in a cuvette or other container, and light from a source is directed through it. The light then passes through a monochromator, which separates it into its component wavelengths. The monochromatic light is then directed through the sample, and the intensity of the transmitted or absorbed light is measured by a detector.

The resulting absorption spectrum can provide information about the concentration and identity of the components in the sample. For example, if a compound has a known absorption maximum at a specific wavelength, its concentration can be determined by measuring the absorbance at that wavelength and comparing it to a standard curve.

Overall, UV-Vis spectrophotometry is a versatile and powerful analytical technique for quantitative and qualitative analysis of various samples in different fields.

Coenzymes are small organic molecules that assist enzymes in catalyzing chemical reactions within cells. They typically act as carriers of specific atoms or groups of atoms during enzymatic reactions, facilitating the conversion of substrates into products. Coenzymes often bind temporarily to enzymes at the active site, forming an enzyme-coenzyme complex.

Coenzymes are usually derived from vitamins or minerals and are essential for maintaining proper metabolic functions in the body. Examples of coenzymes include nicotinamide adenine dinucleotide (NAD+), flavin adenine dinucleotide (FAD), and coenzyme A (CoA). When a coenzyme is used up in a reaction, it must be regenerated or replaced for the enzyme to continue functioning.

In summary, coenzymes are vital organic compounds that work closely with enzymes to facilitate biochemical reactions, ensuring the smooth operation of various metabolic processes within living organisms.

Aspartate aminotransferases (ASTs) are a group of enzymes found in various tissues throughout the body, including the heart, liver, and muscles. They play a crucial role in the metabolic process of transferring amino groups between different molecules.

In medical terms, AST is often used as a blood test to measure the level of this enzyme in the serum. Elevated levels of AST can indicate damage or injury to tissues that contain this enzyme, such as the liver or heart. For example, liver disease, including hepatitis and cirrhosis, can cause elevated AST levels due to damage to liver cells. Similarly, heart attacks can also result in increased AST levels due to damage to heart muscle tissue.

It is important to note that an AST test alone cannot diagnose a specific medical condition, but it can provide valuable information when used in conjunction with other diagnostic tests and clinical evaluation.

Dihydrolipoamide dehydrogenase (DHLD) is an enzyme that plays a crucial role in several important metabolic pathways in the human body, including the citric acid cycle and the catabolism of certain amino acids. DHLD is a component of multi-enzyme complexes, such as the pyruvate dehydrogenase complex (PDC) and the alpha-ketoglutarate dehydrogenase complex (KGDC).

The primary function of DHLD is to catalyze the oxidation of dihydrolipoamide, a reduced form of lipoamide, back to its oxidized state (lipoamide) while simultaneously reducing NAD+ to NADH. This reaction is essential for the continued functioning of the PDC and KGDC, as dihydrolipoamide is a cofactor for these enzyme complexes.

Deficiencies in DHLD can lead to serious metabolic disorders, such as maple syrup urine disease (MSUD) and riboflavin-responsive multiple acyl-CoA dehydrogenase deficiency (RR-MADD). These conditions can result in neurological symptoms, developmental delays, and metabolic acidosis, among other complications. Treatment typically involves dietary modifications, supplementation with specific nutrients, and, in some cases, enzyme replacement therapy.

In the context of medical and biological sciences, a "binding site" refers to a specific location on a protein, molecule, or cell where another molecule can attach or bind. This binding interaction can lead to various functional changes in the original protein or molecule. The other molecule that binds to the binding site is often referred to as a ligand, which can be a small molecule, ion, or even another protein.

The binding between a ligand and its target binding site can be specific and selective, meaning that only certain ligands can bind to particular binding sites with high affinity. This specificity plays a crucial role in various biological processes, such as signal transduction, enzyme catalysis, or drug action.

In the case of drug development, understanding the location and properties of binding sites on target proteins is essential for designing drugs that can selectively bind to these sites and modulate protein function. This knowledge can help create more effective and safer therapeutic options for various diseases.

Zinc is an essential mineral that is vital for the functioning of over 300 enzymes and involved in various biological processes in the human body, including protein synthesis, DNA synthesis, immune function, wound healing, and cell division. It is a component of many proteins and participates in the maintenance of structural integrity and functionality of proteins. Zinc also plays a crucial role in maintaining the sense of taste and smell.

The recommended daily intake of zinc varies depending on age, sex, and life stage. Good dietary sources of zinc include red meat, poultry, seafood, beans, nuts, dairy products, and fortified cereals. Zinc deficiency can lead to various health problems, including impaired immune function, growth retardation, and developmental delays in children. On the other hand, excessive intake of zinc can also have adverse effects on health, such as nausea, vomiting, and impaired immune function.

PQQ, or pyrroloquinoline quinone, is a redox cofactor that plays a role in the electron transfer chain and is involved in various redox reactions in the body. It can be found in some bacteria and plants, and there is evidence to suggest that it may also be present in human tissues. However, the exact role of PQQ as a cofactor in humans is not well understood and more research is needed to fully understand its functions and potential health benefits.

A cofactor is a non-protein chemical compound that is required for an enzyme to function. Cofactors can be inorganic ions, such as iron or magnesium, or organic molecules, like PQQ. They play a crucial role in catalyzing biochemical reactions and maintaining the structural integrity of proteins.

In summary, PQQ is a redox cofactor that may have a role in various redox reactions in the body, but its exact functions and significance in human health are still being studied.

Tryptophanase is not a medical term per se, but rather a biochemical term used to describe an enzyme. However, I can provide a biochemical definition for you:

Tryptophanase (TPase or TnaA) is a pyridoxal-phosphate (PLP) dependent enzyme found in certain bacteria, such as Escherichia coli, that catalyzes the breakdown of the essential amino acid tryptophan into several compounds. The primary reaction catalyzed by tryptophanase is the conversion of L-tryptophan to indole, pyruvate, and ammonia. This reaction also produces ATP and ADP as co-products.

The production of indole from tryptophan by tryptophanase has diagnostic value in microbiology, as the presence of indole in a culture medium can indicate the growth of certain bacterial species that produce this enzyme.

Cobamides are a class of compounds that are structurally related to vitamin B12 (cobalamin). They consist of a corrin ring, which is a large heterocyclic ring made up of four pyrrole rings, and a cobalt ion in the center. The lower axial ligand of the cobalt ion can be a variety of different groups, including cyano, hydroxo, methyl, or 5'-deoxyadenosyl groups.

Cobamides are involved in a number of important biological processes, including the synthesis of amino acids and nucleotides, the metabolism of fatty acids and cholesterol, and the regulation of gene expression. They function as cofactors for enzymes called cobamide-dependent methyltransferases, which transfer methyl groups (CH3) from one molecule to another.

Cobamides are found in a wide variety of organisms, including bacteria, archaea, and eukaryotes. In humans, the most important cobamide is vitamin B12, which is essential for the normal functioning of the nervous system and the production of red blood cells. Vitamin B12 deficiency can lead to neurological problems and anemia.

Propanediol Dehydratase is not a medical term per se, but rather a biochemical term. It refers to an enzyme that catalyzes the conversion of 1,2-propanediol (also known as propylene glycol) into propionaldehyde and water in the metabolic pathway known as the glycerol/propanediol utilization (GUD) system.

The reaction catalyzed by Propanediol Dehydratase is:

This enzyme is found in certain bacteria and archaea that are capable of utilizing 1,2-propanediol as a carbon source for growth. Deficiency or absence of this enzyme can affect the metabolic capabilities of these microorganisms.

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

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

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

Protein conformation refers to the specific three-dimensional shape that a protein molecule assumes due to the spatial arrangement of its constituent amino acid residues and their associated chemical groups. This complex structure is determined by several factors, including covalent bonds (disulfide bridges), hydrogen bonds, van der Waals forces, and ionic bonds, which help stabilize the protein's unique conformation.

Protein conformations can be broadly classified into two categories: primary, secondary, tertiary, and quaternary structures. The primary structure represents the linear sequence of amino acids in a polypeptide chain. The secondary structure arises from local interactions between adjacent amino acid residues, leading to the formation of recurring motifs such as α-helices and β-sheets. Tertiary structure refers to the overall three-dimensional folding pattern of a single polypeptide chain, while quaternary structure describes the spatial arrangement of multiple folded polypeptide chains (subunits) that interact to form a functional protein complex.

Understanding protein conformation is crucial for elucidating protein function, as the specific three-dimensional shape of a protein directly influences its ability to interact with other molecules, such as ligands, nucleic acids, or other proteins. Any alterations in protein conformation due to genetic mutations, environmental factors, or chemical modifications can lead to loss of function, misfolding, aggregation, and disease states like neurodegenerative disorders and cancer.

Fluorescence spectrometry is a type of analytical technique used to investigate the fluorescent properties of a sample. It involves the measurement of the intensity of light emitted by a substance when it absorbs light at a specific wavelength and then re-emits it at a longer wavelength. This process, known as fluorescence, occurs because the absorbed energy excites electrons in the molecules of the substance to higher energy states, and when these electrons return to their ground state, they release the excess energy as light.

Fluorescence spectrometry typically measures the emission spectrum of a sample, which is a plot of the intensity of emitted light versus the wavelength of emission. This technique can be used to identify and quantify the presence of specific fluorescent molecules in a sample, as well as to study their photophysical properties.

Fluorescence spectrometry has many applications in fields such as biochemistry, environmental science, and materials science. For example, it can be used to detect and measure the concentration of pollutants in water samples, to analyze the composition of complex biological mixtures, or to study the properties of fluorescent nanomaterials.

Tyrosine decarboxylase is an enzyme that catalyzes the decarboxylation of the amino acid tyrosine to form the biogenic amine tyramine. The reaction occurs in the absence of molecular oxygen and requires pyridoxal phosphate as a cofactor. Tyrosine decarboxylase is found in various bacteria, fungi, and plants, and it plays a role in the biosynthesis of alkaloids and other natural products. In humans, tyrosine decarboxylase is not normally present, but its activity has been detected in some tumors and is associated with the production of neurotransmitters in neuronal cells.

Transketolase is an enzyme found in most organisms, from bacteria to humans. It plays a crucial role in the pentose phosphate pathway (PPP), which is a metabolic pathway that runs alongside glycolysis in the cell cytoplasm. The PPP provides an alternative way of generating energy and also serves to provide building blocks for new cellular components, particularly nucleotides.

Transketolase functions by catalyzing the transfer of a two-carbon ketol group from a ketose (a sugar containing a ketone functional group) to an aldose (a sugar containing an aldehyde functional group). This reaction forms a new ketose and an aldose, effectively converting three-carbon sugars into five-carbon sugars, or vice versa.

In humans, transketolase is essential for the production of NADPH, an important reducing agent in the cell, and for the synthesis of certain amino acids and nucleotides. Deficiencies in this enzyme can lead to metabolic disorders such as pentosuria.

Glycine hydroxymethyltransferase (GHMT or GHT) is an enzyme that plays a crucial role in the metabolic pathway called the methylation cycle, specifically in the synthesis of the amino acid serine and the conversion of glycine. It catalyzes the reversible reaction between glycine and methylene tetrahydrofolate (MTHF) to produce 5,10-methylenetetrahydrofolate and sarcosine.

The reaction can be represented as follows:
Glycine + MTHF ↔ Sarcosine + 5,10-methylenetetrahydrofolate

This enzyme is widely distributed in various tissues, including the liver, kidney, and pancreas. In addition to its role in amino acid metabolism, GHMT also contributes to the regulation of one-carbon metabolism, which is essential for methylation reactions, DNA synthesis, and cellular homeostasis.

Pyruvate oxidase is not a term that has a widely recognized medical definition. However, pyruvate oxidase is an enzyme that plays a role in the metabolism of glucose in cells. It is involved in the conversion of pyruvate, a product of glycolysis, into acetyl-CoA, which can then be used in the citric acid cycle (also known as the Krebs cycle) to generate energy in the form of ATP.

Pyruvate oxidase is found in the mitochondria of cells and requires molecular oxygen (O2) to function. It catalyzes the following reaction:

pyruvate + CoA + NAD+ + H2O → acetyl-CoA + CO2 + NADH + H+

Deficiencies in pyruvate oxidase have been associated with certain metabolic disorders, such as pyruvate dehydrogenase deficiency and Leigh syndrome. However, these conditions are typically caused by defects in other enzymes involved in the metabolism of pyruvate rather than pyruvate oxidase itself.

Catalysis is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst, which remains unchanged at the end of the reaction. A catalyst lowers the activation energy required for the reaction to occur, thereby allowing the reaction to proceed more quickly and efficiently. This can be particularly important in biological systems, where enzymes act as catalysts to speed up metabolic reactions that are essential for life.

Protein binding, in the context of medical and biological sciences, refers to the interaction between a protein and another molecule (known as the ligand) that results in a stable complex. This process is often reversible and can be influenced by various factors such as pH, temperature, and concentration of the involved molecules.

In clinical chemistry, protein binding is particularly important when it comes to drugs, as many of them bind to proteins (especially albumin) in the bloodstream. The degree of protein binding can affect a drug's distribution, metabolism, and excretion, which in turn influence its therapeutic effectiveness and potential side effects.

Protein-bound drugs may be less available for interaction with their target tissues, as only the unbound or "free" fraction of the drug is active. Therefore, understanding protein binding can help optimize dosing regimens and minimize adverse reactions.

Thiamine pyrophosphate (TPP) is the active form of thiamine (vitamin B1) that plays a crucial role as a cofactor in various enzymatic reactions, particularly in carbohydrate metabolism. TPP is essential for the functioning of three key enzymes: pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, and transketolase. These enzymes are involved in critical processes such as the conversion of pyruvate to acetyl-CoA, the oxidative decarboxylation of alpha-ketoglutarate in the Krebs cycle, and the pentose phosphate pathway, which is important for generating reducing equivalents (NADPH) and ribose sugars for nucleotide synthesis. A deficiency in thiamine or TPP can lead to severe neurological disorders, including beriberi and Wernicke-Korsakoff syndrome, which are often observed in alcoholics due to poor nutrition and impaired thiamine absorption.

Cobalt is a chemical element with the symbol Co and atomic number 27. It is a hard, silver-white, lustrous, and brittle metal that is found naturally only in chemically combined form, except for small amounts found in meteorites. Cobalt is used primarily in the production of magnetic, wear-resistant, and high-strength alloys, as well as in the manufacture of batteries, magnets, and pigments.

In a medical context, cobalt is sometimes used in the form of cobalt-60, a radioactive isotope, for cancer treatment through radiation therapy. Cobalt-60 emits gamma rays that can be directed at tumors to destroy cancer cells. Additionally, small amounts of cobalt are present in some vitamin B12 supplements and fortified foods, as cobalt is an essential component of vitamin B12. However, exposure to high levels of cobalt can be harmful and may cause health effects such as allergic reactions, lung damage, heart problems, and neurological issues.

Pyruvate decarboxylase is an enzyme that plays a crucial role in the cellular process of fermentation and gluconeogenesis. In medical and biochemical terms, pyruvate decarboxylase is defined as:

"An enzyme (EC that catalyzes the decarboxylation of pyruvate to form acetaldehyde and carbon dioxide in the presence of thiamine pyrophosphate (TPP) as a cofactor. This reaction occurs during anaerobic metabolism, such as alcohol fermentation in yeast or bacteria, and helps to generate ATP and NADH for the cell's energy needs."

In humans, pyruvate decarboxylase is primarily found in the liver and kidneys, where it participates in gluconeogenesis – the process of generating new glucose molecules from non-carbohydrate precursors. The enzyme's activity is essential for maintaining blood glucose levels during fasting or low-carbohydrate intake.

Deficiencies in pyruvate decarboxylase can lead to metabolic disorders, such as pyruvate decarboxylase deficiency (PDC deficiency), which is characterized by lactic acidosis, developmental delays, and neurological issues. Proper diagnosis and management of these conditions often involve monitoring enzyme activity and glucose metabolism.

Dithionitrobenzoic acid is not a medical term, as it is related to chemistry rather than medicine. It is an organic compound with the formula C6H4N2O4S2. This compound is a type of benzenediol that contains two sulfur atoms and two nitro groups. It is a white crystalline powder that is soluble in water and alcohol.

Dithionitrobenzoic acid is not used directly in medical applications, but it can be used as a reagent in chemical reactions that are relevant to medical research or analysis. For example, it can be used to determine the concentration of iron in biological samples through a reaction that produces a colored complex. However, if you have any specific questions related to its use or application in a medical context, I would recommend consulting with a medical professional or a researcher in the relevant field.

Ethanolamine ammonia-lyase (EAL) is an enzyme that plays a role in the breakdown and metabolism of certain compounds in the body. Its primary function is to catalyze the conversion of ethanolamine, a type of amino alcohol, into acetaldehyde and ammonia. This reaction is an important step in the catabolism of phosphatidylethanolamines, which are major components of cell membranes.

EAL is also known as "ethanolamine deaminase" or "N-ethanolamine deaminase." It requires the cofactor pyridoxal phosphate (PLP) to facilitate the reaction. The enzyme's activity has been identified in various organisms, including bacteria, archaea, and plants, but not in mammals. In some bacterial species, EAL is involved in the biosynthesis of certain amino acids and other biomolecules.

The reaction catalyzed by ethanolamine ammonia-lyase:

Ethanolamine + H2O + PLP → Acetaldehyde + Ammonia + Methylglyoxal + PLP

Enzyme stability refers to the ability of an enzyme to maintain its structure and function under various environmental conditions, such as temperature, pH, and the presence of denaturants or inhibitors. A stable enzyme retains its activity and conformation over time and across a range of conditions, making it more suitable for industrial and therapeutic applications.

Enzymes can be stabilized through various methods, including chemical modification, immobilization, and protein engineering. Understanding the factors that affect enzyme stability is crucial for optimizing their use in biotechnology, medicine, and research.

A lyase is a type of enzyme that catalyzes the breaking of various chemical bonds in a molecule, often resulting in the formation of two new molecules. Lyases differ from other types of enzymes, such as hydrolases and oxidoreductases, because they create double bonds or rings as part of their reaction mechanism.

In the context of medical terminology, lyases are not typically discussed on their own, but rather as a type of enzyme that can be involved in various biochemical reactions within the body. For example, certain lyases play a role in the metabolism of carbohydrates, lipids, and amino acids, among other molecules.

One specific medical application of lyase enzymes is in the diagnosis of certain genetic disorders. For instance, individuals with hereditary fructose intolerance (HFI) lack the enzyme aldolase B, which is a type of lyase that helps break down fructose in the liver. By measuring the activity of aldolase B in a patient's blood or tissue sample, doctors can diagnose HFI and recommend appropriate dietary restrictions to manage the condition.

Overall, while lyases are not a medical diagnosis or condition themselves, they play important roles in various biochemical processes within the body and can be useful in the diagnosis of certain genetic disorders.

Glucose dehydrogenases (GDHs) are a group of enzymes that catalyze the oxidation of glucose to generate gluconic acid or glucuronic acid. This reaction involves the transfer of electrons from glucose to an electron acceptor, most commonly nicotinamide adenine dinucleotide (NAD+) or phenazine methosulfate (PMS).

GDHs are widely distributed in nature and can be found in various organisms, including bacteria, fungi, plants, and animals. They play important roles in different biological processes, such as glucose metabolism, energy production, and detoxification of harmful substances. Based on their cofactor specificity, GDHs can be classified into two main types: NAD(P)-dependent GDHs and PQQ-dependent GDHs.

NAD(P)-dependent GDHs use NAD+ or NADP+ as a cofactor to oxidize glucose to glucono-1,5-lactone, which is then hydrolyzed to gluconic acid by an accompanying enzyme. These GDHs are involved in various metabolic pathways, such as the Entner-Doudoroff pathway and the oxidative pentose phosphate pathway.

PQQ-dependent GDHs, on the other hand, use pyrroloquinoline quinone (PQQ) as a cofactor to catalyze the oxidation of glucose to gluconic acid directly. These GDHs are typically found in bacteria and play a role in energy production and detoxification.

Overall, glucose dehydrogenases are essential enzymes that contribute to the maintenance of glucose homeostasis and energy balance in living organisms.

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

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

Tryptophan oxygenase, also known as tryptophan 2,3-dioxygenase (TDO) or tryptophan pyrrolase, is an enzyme that catalyzes the breakdown of the essential amino acid tryptophan. This enzyme requires molecular oxygen and plays a crucial role in regulating tryptophan levels within the body.

The reaction catalyzed by tryptophan oxygenase involves the oxidation of the indole ring of tryptophan, leading to the formation of N-formylkynurenine. This metabolite is further broken down through several enzymatic steps to produce other biologically active compounds, such as kynurenine and niacin (vitamin B3).

Tryptophan oxygenase activity is primarily found in the liver and is induced by various factors, including corticosteroids, cytokines, and tryptophan itself. The regulation of this enzyme has implications for several physiological processes, such as immune response, neurotransmitter synthesis, and energy metabolism. Dysregulation of tryptophan oxygenase activity can contribute to the development of various pathological conditions, including neurological disorders and cancer.

L-serine dehydratase is an enzyme that plays a role in the metabolism of certain amino acids. Specifically, it catalyzes the conversion of L-serine to pyruvate and ammonia. This reaction is part of the pathway that breaks down L-serine to produce energy and intermediates for other biochemical processes in the body.

The systematic name for this enzyme is L-serine deaminase (pyruvate-forming). It is classified as a member of the lyase family of enzymes, which are characterized by their ability to catalyze the breaking of various chemical bonds using a cofactor to provide the energy needed for the reaction. In the case of L-serine dehydratase, the cofactor is a derivative of vitamin B6 called pyridoxal 5'-phosphate (PLP).

Deficiencies or mutations in the gene that encodes L-serine dehydratase can lead to various metabolic disorders, including hypermethioninemia and homocystinuria. These conditions are characterized by abnormal levels of certain amino acids in the blood and urine, which can have serious health consequences if left untreated.

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

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

Ornithine-oxo-acid transaminase (OAT), also known as ornithine aminotransferase, is a urea cycle enzyme that catalyzes the reversible transfer of an amino group from ornithine to α-ketoglutarate, producing glutamate semialdehyde and glutamate. This reaction is an essential part of the urea cycle, which is responsible for the detoxification of ammonia in the body. Deficiencies in OAT can lead to a genetic disorder called ornithine transcarbamylase deficiency (OTCD), which can cause hyperammonemia and neurological symptoms.

Glucose 1-Dehydrogenase (G1DH) is an enzyme that catalyzes the oxidation of β-D-glucose into D-glucono-1,5-lactone and reduces the cofactor NAD+ into NADH. This reaction plays a role in various biological processes, including glucose sensing and detoxification of reactive carbonyl species. G1DH is found in many organisms, including humans, and has several isoforms with different properties and functions.

Glucose oxidase (GOD) is an enzyme that catalyzes the oxidation of D-glucose to D-glucono-1,5-lactone, while reducing oxygen to hydrogen peroxide in the process. This reaction is a part of the metabolic pathway in some organisms that convert glucose into energy. The systematic name for this enzyme is D-glucose:oxygen 1-oxidoreductase.

Glucose oxidase is commonly found in certain fungi, such as Aspergillus niger, and it has various applications in industry, medicine, and research. For instance, it's used in the production of glucose sensors for monitoring blood sugar levels, in the detection and quantification of glucose in food and beverages, and in the development of biosensors for environmental monitoring.

It's worth noting that while glucose oxidase has many applications, it should not be confused with glutathione peroxidase, another enzyme involved in the reduction of hydrogen peroxide to water.

A holozyme is not a specific medical term, but rather a term used in biochemistry to refer to the complete, active form of an enzyme. An enzyme is a biological molecule that catalyzes chemical reactions in the body, and it is often made up of several different subunits or components.

The term "holozyme" comes from the Greek words "holos," meaning whole, and "enzyma," meaning in yeast. It was originally used to describe the active form of enzymes found in yeast cells, but it is now used more broadly to refer to any complete, active enzyme complex.

A holozyme typically consists of two types of subunits: a catalytic subunit, which contains the active site where the substrate binds and the reaction takes place, and one or more regulatory subunits, which control the activity of the enzyme under different conditions. The regulatory subunits may be activated or inhibited by various signals, such as hormones, metabolites, or other molecules, allowing the enzyme to respond to changes in the cellular environment.

In summary, a holozyme is the fully assembled and functional form of an enzyme, consisting of one or more catalytic subunits and one or more regulatory subunits that work together to carry out specific biochemical reactions in the body.

X-ray crystallography is a technique used in structural biology to determine the three-dimensional arrangement of atoms in a crystal lattice. In this method, a beam of X-rays is directed at a crystal and diffracts, or spreads out, into a pattern of spots called reflections. The intensity and angle of each reflection are measured and used to create an electron density map, which reveals the position and type of atoms in the crystal. This information can be used to determine the molecular structure of a compound, including its shape, size, and chemical bonds. X-ray crystallography is a powerful tool for understanding the structure and function of biological macromolecules such as proteins and nucleic acids.

Sulfhydryl compounds, also known as thiol compounds, are organic compounds that contain a functional group consisting of a sulfur atom bonded to a hydrogen atom (-SH). This functional group is also called a sulfhydryl group. Sulfhydryl compounds can be found in various biological systems and play important roles in maintaining the structure and function of proteins, enzymes, and other biomolecules. They can also act as antioxidants and help protect cells from damage caused by reactive oxygen species. Examples of sulfhydryl compounds include cysteine, glutathione, and coenzyme A.

Transaminases, also known as aminotransferases, are a group of enzymes found in various tissues of the body, particularly in the liver, heart, muscle, and kidneys. They play a crucial role in the metabolism of amino acids, the building blocks of proteins.

There are two major types of transaminases: aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Both enzymes are normally present in low concentrations in the bloodstream. However, when tissues that contain these enzymes are damaged or injured, such as during liver disease or muscle damage, the levels of AST and ALT in the blood may significantly increase.

Measurement of serum transaminase levels is a common laboratory test used to assess liver function and detect liver injury or damage. Increased levels of these enzymes in the blood can indicate conditions such as hepatitis, liver cirrhosis, drug-induced liver injury, heart attack, and muscle disorders. It's important to note that while elevated transaminase levels may suggest liver disease, they do not specify the type or cause of the condition, and further diagnostic tests are often required for accurate diagnosis and treatment.

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

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

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

Pyridoxine is the chemical name for Vitamin B6. According to the medical definition, Pyridoxine is a water-soluble vitamin that is part of the B-vitamin complex and is essential for the metabolism of proteins, carbohydrates, and fats. It plays a vital role in the regulation of homocysteine levels in the body, the formation of neurotransmitters such as serotonin and dopamine, and the synthesis of hemoglobin.

Pyridoxine can be found naturally in various foods, including whole grains, legumes, vegetables, nuts, seeds, meat, poultry, and fish. It is also available as a dietary supplement and may be prescribed by healthcare providers to treat or prevent certain medical conditions, such as vitamin B6 deficiency, anemia, seizures, and carpal tunnel syndrome.

Like other water-soluble vitamins, Pyridoxine cannot be stored in the body and must be replenished regularly through diet or supplementation. Excessive intake of Pyridoxine can lead to toxicity symptoms such as nerve damage, skin lesions, and light sensitivity.

Flavins are a group of naturally occurring organic compounds that contain a characteristic isoalloxazine ring, which is a tricyclic aromatic structure. The most common and well-known flavin is flavin adenine dinucleotide (FAD), which plays a crucial role as a coenzyme in various biological oxidation-reduction reactions. FAD accepts electrons and hydrogens to form the reduced form, flavin adenine dinucleotide hydride (FADH2). Another important flavin is flavin mononucleotide (FMN), which is derived from FAD and functions similarly as a coenzyme. Flavins are yellow in color and can be found in various biological systems, including animals, plants, and microorganisms. They are involved in several metabolic pathways, such as the electron transport chain, where they contribute to energy production.

Isomerases are a class of enzymes that catalyze the interconversion of isomers of a single molecule. They do this by rearranging atoms within a molecule to form a new structural arrangement or isomer. Isomerases can act on various types of chemical bonds, including carbon-carbon and carbon-oxygen bonds.

There are several subclasses of isomerases, including:

1. Racemases and epimerases: These enzymes interconvert stereoisomers, which are molecules that have the same molecular formula but different spatial arrangements of their atoms in three-dimensional space.
2. Cis-trans isomerases: These enzymes interconvert cis and trans isomers, which differ in the arrangement of groups on opposite sides of a double bond.
3. Intramolecular oxidoreductases: These enzymes catalyze the transfer of electrons within a single molecule, resulting in the formation of different isomers.
4. Mutases: These enzymes catalyze the transfer of functional groups within a molecule, resulting in the formation of different isomers.
5. Tautomeres: These enzymes catalyze the interconversion of tautomers, which are isomeric forms of a molecule that differ in the location of a movable hydrogen atom and a double bond.

Isomerases play important roles in various biological processes, including metabolism, signaling, and regulation.

Macromolecular substances, also known as macromolecules, are large, complex molecules made up of repeating subunits called monomers. These substances are formed through polymerization, a process in which many small molecules combine to form a larger one. Macromolecular substances can be naturally occurring, such as proteins, DNA, and carbohydrates, or synthetic, such as plastics and synthetic fibers.

In the context of medicine, macromolecular substances are often used in the development of drugs and medical devices. For example, some drugs are designed to bind to specific macromolecules in the body, such as proteins or DNA, in order to alter their function and produce a therapeutic effect. Additionally, macromolecular substances may be used in the creation of medical implants, such as artificial joints and heart valves, due to their strength and durability.

It is important for healthcare professionals to have an understanding of macromolecular substances and how they function in the body, as this knowledge can inform the development and use of medical treatments.

Crystallization is a process in which a substance transitions from a liquid or dissolved state to a solid state, forming a crystal lattice. In the medical context, crystallization can refer to the formation of crystals within the body, which can occur under certain conditions such as changes in pH, temperature, or concentration of solutes. These crystals can deposit in various tissues and organs, leading to the formation of crystal-induced diseases or disorders.

For example, in patients with gout, uric acid crystals can accumulate in joints, causing inflammation, pain, and swelling. Similarly, in nephrolithiasis (kidney stones), minerals in the urine can crystallize and form stones that can obstruct the urinary tract. Crystallization can also occur in other medical contexts, such as in the formation of dental calculus or plaque, and in the development of cataracts in the eye.

Urease is an enzyme that catalyzes the hydrolysis of urea into ammonia and carbon dioxide. It is found in various organisms, including bacteria, fungi, and plants. In medicine, urease is often associated with certain bacterial infections, such as those caused by Helicobacter pylori, which can produce large amounts of this enzyme. The presence of urease in these infections can lead to increased ammonia production, contributing to the development of gastritis and peptic ulcers.

Molecular weight, also known as molecular mass, is the mass of a molecule. It is expressed in units of atomic mass units (amu) or daltons (Da). Molecular weight is calculated by adding up the atomic weights of each atom in a molecule. It is a useful property in chemistry and biology, as it can be used to determine the concentration of a substance in a solution, or to calculate the amount of a substance that will react with another in a chemical reaction.

Flavin Mononucleotide (FMN) is a coenzyme that plays a crucial role in biological oxidation-reduction reactions. It is derived from the vitamin riboflavin (also known as vitamin B2) and is composed of a flavin molecule bonded to a nucleotide. FMN functions as an electron carrier, accepting and donating electrons in various metabolic pathways, including the citric acid cycle and the electron transport chain, which are essential for energy production in cells. It also participates in the detoxification of harmful substances and contributes to the maintenance of cellular redox homeostasis. FMN can exist in two forms: the oxidized form (FMN) and the reduced form (FMNH2), depending on its involvement in redox reactions.

Substrate specificity in the context of medical biochemistry and enzymology refers to the ability of an enzyme to selectively bind and catalyze a chemical reaction with a particular substrate (or a group of similar substrates) while discriminating against other molecules that are not substrates. This specificity arises from the three-dimensional structure of the enzyme, which has evolved to match the shape, charge distribution, and functional groups of its physiological substrate(s).

Substrate specificity is a fundamental property of enzymes that enables them to carry out highly selective chemical transformations in the complex cellular environment. The active site of an enzyme, where the catalysis takes place, has a unique conformation that complements the shape and charge distribution of its substrate(s). This ensures efficient recognition, binding, and conversion of the substrate into the desired product while minimizing unwanted side reactions with other molecules.

Substrate specificity can be categorized as:

1. Absolute specificity: An enzyme that can only act on a single substrate or a very narrow group of structurally related substrates, showing no activity towards any other molecule.
2. Group specificity: An enzyme that prefers to act on a particular functional group or class of compounds but can still accommodate minor structural variations within the substrate.
3. Broad or promiscuous specificity: An enzyme that can act on a wide range of structurally diverse substrates, albeit with varying catalytic efficiencies.

Understanding substrate specificity is crucial for elucidating enzymatic mechanisms, designing drugs that target specific enzymes or pathways, and developing biotechnological applications that rely on the controlled manipulation of enzyme activities.

In the context of medicine, there is no specific medical definition for 'metals.' However, certain metals have significant roles in biological systems and are thus studied in physiology, pathology, and pharmacology. Some metals are essential to life, serving as cofactors for enzymatic reactions, while others are toxic and can cause harm at certain levels.

Examples of essential metals include:

1. Iron (Fe): It is a crucial component of hemoglobin, myoglobin, and various enzymes involved in energy production, DNA synthesis, and electron transport.
2. Zinc (Zn): This metal is vital for immune function, wound healing, protein synthesis, and DNA synthesis. It acts as a cofactor for over 300 enzymes.
3. Copper (Cu): Copper is essential for energy production, iron metabolism, antioxidant defense, and connective tissue formation. It serves as a cofactor for several enzymes.
4. Magnesium (Mg): Magnesium plays a crucial role in many biochemical reactions, including nerve and muscle function, protein synthesis, and blood pressure regulation.
5. Manganese (Mn): This metal is necessary for bone development, protein metabolism, and antioxidant defense. It acts as a cofactor for several enzymes.
6. Molybdenum (Mo): Molybdenum is essential for the function of certain enzymes involved in the metabolism of nucleic acids, proteins, and drugs.
7. Cobalt (Co): Cobalt is a component of vitamin B12, which plays a vital role in DNA synthesis, fatty acid metabolism, and nerve function.

Examples of toxic metals include:

1. Lead (Pb): Exposure to lead can cause neurological damage, anemia, kidney dysfunction, and developmental issues.
2. Mercury (Hg): Mercury is highly toxic and can cause neurological problems, kidney damage, and developmental issues.
3. Arsenic (As): Arsenic exposure can lead to skin lesions, cancer, neurological disorders, and cardiovascular diseases.
4. Cadmium (Cd): Cadmium is toxic and can cause kidney damage, bone demineralization, and lung irritation.
5. Chromium (Cr): Excessive exposure to chromium can lead to skin ulcers, respiratory issues, and kidney and liver damage.

In medical terms, "bromides" refer to salts or compounds that contain bromine, a chemical element. Historically, potassium bromide was used as a sedative and anticonvulsant in the 19th and early 20th centuries. However, its use has largely been discontinued due to side effects such as neurotoxicity and kidney damage.

In modern medical language, "bromides" can also refer to something that is unoriginal, dull, or lacking in creativity, often used to describe ideas or expressions that are trite or clichéd. This usage comes from the fact that bromide salts were once commonly used as a sedative and were associated with a lack of excitement or energy.

Divalent cations are ions that carry a positive charge of +2. They are called divalent because they have two positive charges. Common examples of divalent cations include calcium (Ca²+), magnesium (Mg²+), and iron (Fe²+). These ions play important roles in various biological processes, such as muscle contraction, nerve impulse transmission, and bone metabolism. They can also interact with certain drugs and affect their absorption, distribution, and elimination in the body.

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

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is an enzyme that plays a crucial role in the metabolic pathway of glycolysis. Its primary function is to convert glyceraldehyde-3-phosphate (a triose sugar phosphate) into D-glycerate 1,3-bisphosphate, while also converting nicotinamide adenine dinucleotide (NAD+) into its reduced form NADH. This reaction is essential for the production of energy in the form of adenosine triphosphate (ATP) during cellular respiration. GAPDH has also been implicated in various non-metabolic processes, including DNA replication, repair, and transcription regulation, due to its ability to interact with different proteins and nucleic acids.

Protein denaturation is a process in which the native structure of a protein is altered, leading to loss of its biological activity. This can be caused by various factors such as changes in temperature, pH, or exposure to chemicals or radiation. The three-dimensional shape of a protein is crucial for its function, and denaturation causes the protein to lose this shape, resulting in impaired or complete loss of function. Denaturation is often irreversible and can lead to the aggregation of proteins, which can have negative effects on cellular function and can contribute to diseases such as Alzheimer's and Parkinson's.

Guanidines are organic compounds that contain a guanidino group, which is a functional group with the formula -NH-C(=NH)-NH2. Guanidines can be found in various natural sources, including some animals, plants, and microorganisms. They also occur as byproducts of certain metabolic processes in the body.

In a medical context, guanidines are most commonly associated with the treatment of muscle weakness and neuromuscular disorders. The most well-known guanidine compound is probably guanidine hydrochloride, which has been used as a medication to treat conditions such as myasthenia gravis and Eaton-Lambert syndrome.

However, the use of guanidines as medications has declined in recent years due to their potential for toxicity and the development of safer and more effective treatments. Today, guanidines are mainly used in research settings to study various biological processes, including protein folding and aggregation, enzyme inhibition, and cell signaling.

Anilino Naphthalenesulfonates are a group of compounds that contain both aniline and naphthalene sulfonate components. Aniline is a organic compound with the formula C6H5NH2, and naphthalene sulfonate is the sodium salt of naphthalene-1,5-disulfonic acid.

Anilino Naphthalenesulfonates are commonly used as fluorescent dyes in various applications such as histology, microscopy, and flow cytometry. These compounds exhibit strong fluorescence under ultraviolet light and can be used to label and visualize specific structures or molecules of interest. Examples of Anilino Naphthalenesulfonates include Propidium Iodide, Acridine Orange, and Hoechst 33258.

It is important to note that while these compounds are widely used in research and diagnostic settings, they may also have potential hazards and should be handled with appropriate safety precautions.

Dialysis is a medical treatment that is used to remove waste and excess fluid from the blood when the kidneys are no longer able to perform these functions effectively. This life-sustaining procedure uses a specialized machine, called a dialyzer or artificial kidney, to filter the blood outside of the body and return clean, chemically balanced blood back into the body.

There are two main types of dialysis: hemodialysis and peritoneal dialysis.

1. Hemodialysis: In this method, a patient's blood is passed through an external filter (dialyzer) that removes waste products, toxins, and excess fluids. The cleaned blood is then returned to the body with the help of a specialized machine. Hemodialysis typically requires access to a large vein, often created by a surgical procedure called an arteriovenous (AV) fistula or graft. Hemodialysis sessions usually last for about 3-5 hours and are performed three times a week in a clinical setting, such as a dialysis center or hospital.
2. Peritoneal Dialysis: This method uses the lining of the patient's own abdomen (peritoneum) as a natural filter to clean the blood. A sterile dialysate solution is introduced into the peritoneal cavity via a permanently implanted catheter. The solution absorbs waste products and excess fluids from the blood vessels lining the peritoneum through a process called diffusion. After a dwell time, usually several hours, the used dialysate is drained out and replaced with fresh dialysate. This process is known as an exchange and is typically repeated multiple times throughout the day or night, depending on the specific type of peritoneal dialysis (continuous ambulatory peritoneal dialysis or automated peritoneal dialysis).

Both methods have their advantages and disadvantages, and the choice between them depends on various factors, such as a patient's overall health, lifestyle, and personal preferences. Dialysis is a life-saving treatment for people with end-stage kidney disease or severe kidney dysfunction, allowing them to maintain their quality of life and extend their lifespan until a kidney transplant becomes available or their kidney function improves.

Methylmalonic acid (MMA) is an organic compound that is produced in the human body during the metabolism of certain amino acids, including methionine and threonine. It is a type of fatty acid that is intermediate in the breakdown of these amino acids in the liver and other tissues.

Under normal circumstances, MMA is quickly converted to succinic acid, which is then used in the Krebs cycle to generate energy in the form of ATP. However, when there are deficiencies or mutations in enzymes involved in this metabolic pathway, such as methylmalonyl-CoA mutase, MMA can accumulate in the body and cause methylmalonic acidemia, a rare genetic disorder that affects approximately 1 in every 50,000 to 100,000 individuals worldwide.

Elevated levels of MMA in the blood or urine can be indicative of various metabolic disorders, including methylmalonic acidemia, vitamin B12 deficiency, and renal insufficiency. Therefore, measuring MMA levels is often used as a diagnostic tool to help identify and manage these conditions.

I'm sorry for any confusion, but "spectrum analysis" is not a commonly used medical term. Spectrum analysis is a term that is more frequently used in the fields of physics, mathematics, and engineering to describe the process of breaking down a signal or a wave into its different frequencies and amplitudes, creating a visual representation called a spectrum.

If you have any concerns about a medical issue, I would recommend consulting with a healthcare professional for accurate information and guidance.

Electron Spin Resonance (ESR) Spectroscopy, also known as Electron Paramagnetic Resonance (EPR) Spectroscopy, is a technique used to investigate materials with unpaired electrons. It is based on the principle of absorption of energy by the unpaired electrons when they are exposed to an external magnetic field and microwave radiation.

In this technique, a sample is placed in a magnetic field and microwave radiation is applied. The unpaired electrons in the sample absorb energy and change their spin state when the energy of the microwaves matches the energy difference between the spin states. This absorption of energy is recorded as a function of the magnetic field strength, producing an ESR spectrum.

ESR spectroscopy can provide information about the number, type, and behavior of unpaired electrons in a sample, as well as the local environment around the electron. It is widely used in physics, chemistry, and biology to study materials such as free radicals, transition metal ions, and defects in solids.

Apoenzymes become active enzymes on addition of a cofactor. Cofactors can be either inorganic (e.g., metal ions and iron-sulfur ... An apoenzyme (or, generally, an apoprotein) is the protein without any small-molecule cofactors, substrates, or inhibitors ...
Nair PM, Vining LC (February 1965). "Isophenoxazine synthase apoenzyme from Pycnoporus coccineus". Biochimica et Biophysica ...
I. Purification of the apoenzyme and synthetase; characteristics of the reaction". J. Biol. Chem. 239: 2858-2864. Portal: ...
However, the apoenzyme without copper is unstable. Apoceruloplasmin is largely degraded intracellularly in the hepatocyte and ...
Groen BW, van Kleef MA, Duine JA (March 1986). "Quinohaemoprotein alcohol dehydrogenase apoenzyme from Pseudomonas testosteroni ...
Methylmalonyl-CoA mutase is a mitochondrial homodimer apoenzyme (EC. 5. 4.99.2) that focuses on the catalysis of methylmalonyl ...
Molecular size of the D-amino acid oxidase apoenzyme subunit". J. Biol. Chem. 244 (2): 465-470. doi:10.1016/S0021-9258(18)94452 ...
Isolation of the holo- and apoenzymes and conversion of the apoenzyme to the holoenzyme". The Journal of Biological Chemistry. ...
Isolation of the holo- and apoenzymes and conversion of the apoenzyme to the holoenzyme". The Journal of Biological Chemistry. ...
Isolation of the holo- and apoenzymes and conversion of the apoenzyme to the holoenzyme". The Journal of Biological Chemistry. ...
A complex of the apoenzyme and citrate at 1.87 A resolution". Journal of Molecular Biology. 226 (3): 867-82. doi:10.1016/0022- ...
A complex of the apoenzyme and citrate at 1.87 A resolution". Journal of Molecular Biology. 226 (3): 867-82. doi:10.1016/0022- ...
Crystallographic studies have helped elucidate the apoenzyme structure of phosphopentose epimerase. Results of these studies ...
Recny MA, Hager LP (November 1982). "Reconstitution of native Escherichia coli pyruvate oxidase from apoenzyme monomers and FAD ...
"Structural analysis of N-acetylglucosamine-6-phosphate deacetylase apoenzyme from Escherichia coli". Journal of Molecular ...
"Reconstitution of native Escherichia coli pyruvate oxidase from apoenzyme monomers and FAD". J. Biol. Chem. 257 (21): 12878-86 ...
2. Spectroscopic Studies on the Apoenzyme and the Monomeric and Dimeric Forms". European Journal of Biochemistry. 33 (2): 271-8 ...
17 Enzymes that require a cofactor but do not have one bound are called apoenzymes or apoproteins. An enzyme together with the ...
17 Enzymes that require a cofactor but do not have one bound are called apoenzymes or apoproteins. An enzyme together with the ...
Before addition of the pyridoxal phosphate cofactor, the apoenzyme exists in an open conformation. Upon cofactor binding, a ...
Kamei S, Ohkubo A, Yamanaka M (1979). "Apoenzyme of aspartate aminotransferase isozymes in serum and its diagnostic usefullness ...
... preparation and characterization of the apoenzyme and monomer-dimer equilibrium". Arch. Biochem. Biophys. 337 (1): 89-95. doi: ...
Qi D.F., Wang Y.L., "Studies on Succinic Dehydrogenase V, The Linking between the Flavin Prosthetic Group and the Apoenzyme, ... Wang, Y.L. (1966). "Studies on Succinic Dehydrogenase, Purification, Properties and Linking between the Apoenzyme and the ...
... preparation and characterization of the apoenzyme and monomer-dimer equilibrium". Archives of Biochemistry and Biophysics. 337 ...
... and the properties of the apoenzyme subunits". Acta Biochim. Pol. 13 (4): 311-28. PMID 5962440. SMILEY KL, SOBOLOV M (1962). "A ...
Dewanti AR, Duine JA (May 1998). "Reconstitution of membrane-integrated quinoprotein glucose dehydrogenase apoenzyme with PQQ ...
... the binding process of PQQ to the apoenzymes". Biosci. Biotechnol. Biochem. 59: 1548-1555. doi:10.1271/bbb.59.1548. Soluble+ ...
Apoenzymes can still bind glucose but, due to the lack of cofactors (in vitro), cannot catalyse their reaction so are less ... This protein has also been used in fluorescent sensing either simply as an apoenzyme or as a holoenzyme. An exception to this ... Chinnayelka, S. and M.J. McShane, RET nanobiosensors using affinity of an apo-enzyme toward its substrate. Conf Proc IEEE Eng ... but then switching to GOx apoenzyme in 2004 (TRITC-apo-GOx /FITC-dextran (500kDa)), and in 2009 testing sensors (QSY-21-apo-GOx ...
The apoenzyme, not active and bound to substrates, has an acidic isoelectric point of pH 5.0-5.2. Unusual for proteins, this ...
Three of these were of the wild type: the apoenzyme in 1S2T, the enzyme plus its magnesium ion cofactor in 1S2V, and the enzyme ... A mutant (D58A, in one of the active-site loops) was crystallized as an apoenzyme also (1S2U). From these structures, an active ...
translation of APOENZYMES,translations from English,translation of APOENZYMES English ...
Here, we report NMR structures of the Tpt1 ortholog from the bacterium Runella slithyformis (RslTpt1), as apoenzyme and bound ...
Apoenzymes become active enzymes on addition of a cofactor. Cofactors can be either inorganic (e.g., metal ions and iron-sulfur ... An apoenzyme (or, generally, an apoprotein) is the protein without any small-molecule cofactors, substrates, or inhibitors ...
Crystal structure of apoenzyme cAMP-dependent protein kinase catalytic subunit ... Crystal structure of apoenzyme cAMP-dependent protein kinase catalytic subunit; X-RAY DIFFRACTION 2.90 Å SMTL ID. 1j3h.1. ...
The benzotrifluoride group binds to the N-lobe of the KD (cyan). c, Comparison of the binding pocket of the apo-enzyme (gray) ... a, The ATP-binding site of the PI3KC2α apo-enzyme. The adenine pocket, affinity pocket and hydrophobic pocket II are indicated ... e, Comparison of the binding pocket of the apo-enzyme (gray) and the PI3KC2α-PIK-90 complex (green). Arrows indicate ...
Apoenzyme. Ligan. Definition. Holoenzyme - Enz + Cofactor. Apoenzyme - Enz - cofactor (inactive). Ligand - any small molecule ...
Holoenzymes are the active forms of apoenzymes. Cofactors can be metals or small organic molecules, and their primary function ...
PDB Description: horse liver alcohol dehydrogenase apoenzyme. PDB Compounds: (A:) alcohol dehydrogenase e chain. SCOPe Domain ...
Histone H3 Lysine 4 Demethylating Rice JMJ703 apo enzyme. 4igq. Histone H3 Lysine 4 Demethylating Rice JMJ703 in complex with ... Crystal structure of human JMJD2D/KDM4D apoenzyme. 4igo. Histone H3 Lysine 4 Demethylating rice Rice JMJ703 in complex with ...
Histone H3 Lysine 4 Demethylating Rice JMJ703 apo enzyme. 4igq. Histone H3 Lysine 4 Demethylating Rice JMJ703 in complex with ... Crystal structure of human JMJD2D/KDM4D apoenzyme. 4igo. Histone H3 Lysine 4 Demethylating rice Rice JMJ703 in complex with ...
Distinct genotypic and phenotypic forms of methylmalonyl CoA mutase (MCM) apoenzyme deficiency can be delineated by biochemical ...
The protein components of a number of complexes, such as enzymes (APOENZYMES), ferritin (APOFERRITINS), or lipoproteins ( ...
Crystal structure of apoenzyme cAMP-dependent protein kinase catalytic subunit. 1jbp. Crystal Structure of the Catalytic ... Crystal structure of E230Q mutant of cAMP-dependent protein kinase reveals unexpected apoenzyme conformation. ...
Apo enzyme was prepared in 50 mM sodium phosphate, pH 6.0, by preincubating ScLPMO10DCD in 10 mM ethylenediaminetetraacetic ... 10 °C drop in Tm for the apo enzyme (Supplementary Fig. S6). ...
PLP either remains in the hepatocyte, where it is bound to an apoenzyme, or it is released into the serum, where it is tightly ...
... only three of which are of the apo enzyme. The first two such apo structures (PDB entries 6b8x and 6b8t) are from ...
Crystal soaking experiments with 31-kDa apoenzyme crystals show that, in the absence of DNA, the HhH motif in the fingers ...
PKU is customarily caused by a deficiency of the phenylalanine hydroxylase apoenzyme (PAH), but other causes may include a ...
The enzyme activity of an apoenzyme could be partly restored by addition of membrane extracts containing pyrroloquinoline ...
Apoenzyme: Definition, Function, & Examples September 29, 2021. Disaccharide: Definition, Types, Structure, & Examples ...
TYDAPO - Tyrosine Decarboxylase, Apoenzyme. Scroll to top ...
C) Apoenzymes (D) Proenzymes. 13. An example of ligases is. (A) Succinate thiokinase. (B) Alanine racemase. (C) Fumarase. (D) ... A) Functional unit (B) Apo enzyme. (C) Coenzyme (D) All of these. 5. Gauchers disease is due to the deficiency. of the enzyme: ...
Eisele, F. L., Mauldin, L., Cantrell, C., Zondlo, M. A., Apel, E., Fried, A., Walega, J., Shetter, R., Lefer, B., Floke, F., Weinheimer, A., Avery, M., Vay, S., Sachse, G., Podolske, J., Diskin, G., Barrick, J. D., Singh, H. B., Brune, W., Harder, H., & 10 othersMartinez, M., Bandy, A., Thornton, D., Heikes, B., Kondo, Y., Riemer, D., Sandholm, S., Tan, D., Talbot, R. & Dibb, J., Oct 27 2003, In: Journal of Geophysical Research: Atmospheres. 108, 20, p. GTE 12-1 - 12-20. Research output: Contribution to journal › Article › peer-review ...
apoenzyme 25 buzzingly 33 exoenzyme 30 oxygenize 29 monkeypox 27 chintzily 26 cockneyfy 26 cyclizing 26 frequency 26 hypnotize ... apoenzyme 25 coenzymes 25 cyclizine 25 enzymatic 25 frenzying 25 hydrazine 25 hydrozoan 25 jonnycake 25 nazifying 25 proenzyme ... apoenzymes 26 cyclizines 26 emblazonry 26 expectancy 26 freezingly 26 frenziedly 26 hydrazines 26 hydrozoans 26 isoenzymic 26 ...
The coenzyme on the other hand may undergo reduction while attached to one apoenzyme, and then migrate to another apoenzyme ... Holoenzymes and Apoenzymes:. An enzyme and a coenzyme together form an enzymatically active conjugated protein called the ... Holoenzyme = Apoenzyme + Prosthetic group. The major coenzymes of dehydrogenases are the two dinucleotides, NAD and NADP. The ... The enzyme (protein) component of the holoenzyme is called an apoenzyme. The non-protein coenzyme is called the prosthetic ...
Study enzyems flashcards. Play games, take quizzes, print and more with Easy Notecards.
Here is a table for the list of words that end in me. There is a total of 859 me ending words in this list. As there are hundreds of words in this list, we have not provided definitions here. Please visit Merriam-Webster for a meaning. ...
  • The protein components of a number of complexes, such as enzymes (APOENZYMES), ferritin (APOFERRITINS), or lipoproteins (APOLIPOPROTEINS). (
  • The electron transferring unit of enzymes - apoenzyme and cofactor are deeply buried inside its protein structure, therefore efficient electronic communication between the electrode and the biocatalytic enzyme is inefficient. (
  • Two derivatives, riboflavin 5' phosphate (flavin mononucleotide [FMN]) and riboflavin 5' adenosine diphosphate (flavin adenine dinucleotide [FAD]), are the coenzymes that unite with specific apoenzyme proteins to form flavoprotein enzymes. (
  • The enzyme (protein) component of the holoenzyme is called an apoenzyme. (
  • Holoenzyme = Apoenzyme + Prosthetic group. (
  • However, the holoenzyme-apoenzyme transition did not markedly alter the respective fluorescence properties of either recombinant or pig kidney DDC when excited at 335 nm. (
  • The coenzyme (prosthetic group) may be tightly bound to the apoenzyme or may easily dissociate from it. (
  • The coenzyme on the other hand may undergo reduction while attached to one apoenzyme, and then migrate to another apoenzyme where it can be oxidised. (
  • The enzyme activity of an apoenzyme could be partly restored by addition of membrane extracts containing pyrroloquinoline quinone adducts. (
  • Here, we report NMR structures of the Tpt1 ortholog from the bacterium Runella slithyformis (RslTpt1), as apoenzyme and bound to NAD+. (
  • PLP either remains in the hepatocyte, where it is bound to an apoenzyme, or it is released into the serum, where it is tightly bound to albumin. (
  • Crystal soaking experiments with 31-kDa apoenzyme crystals show that, in the absence of DNA, the HhH motif in the fingers subdomain binds metal ions with either much lower occupancy or not at all, indicating that metal ion binding is dependent on the presence of the DNA substrate. (
  • PKU is customarily caused by a deficiency of the phenylalanine hydroxylase apoenzyme (PAH), but other causes may include a deficiency of dihydropteridine reductase (DHPR) or reduced production of biopterin (BH 4 ). (
  • An apoenzyme is the holoenzyme minus any cofactors ( ENZYME COFACTORS ) or prosthetic groups required for the enzymatic function. (
  • A holoenzyme or an active enzyme is a complex that consists of two parts: the protein part or apoenzyme, and the cofactor part. (
  • Coenzymes participate in catalysis when they bind to the active site of the enzyme (called apoenzyme ) and subsequently form the active enzyme (called holoenzyme). (
  • 2007), which is normally consistent with a well balanced binding from the coenzyme pyridoxal 5-phosphate (PLP) to GAD67, whereas GAD65 oscillates between an inactive apoenzyme and a dynamic holoenzyme (Battaglioli et al. (
  • therefore, coenzymes cannot be isolated from apoenzymes without denaturation of the enzyme proteins. (
  • It consists of a proteins part known as apoenzyme and non-protein part called prosthetic group (coenzyme of a metal ion). (
  • Two derivatives, riboflavin 5' phosphate (flavin mononucleotide [FMN]) and riboflavin 5' adenosine diphosphate (flavin adenine dinucleotide [FAD]), are the coenzymes that unite with specific apoenzyme proteins to form flavoprotein enzymes. (
  • The electron transferring unit of enzymes - apoenzyme and cofactor are deeply buried inside its protein structure, therefore efficient electronic communication between the electrode and the biocatalytic enzyme is inefficient. (
  • The protein part or the apoenzyme cannot function alone and needs to be activated by the cofactor. (
  • Apoenzyme refers to an enzyme that is devoid of a cofactor. (
  • The structures of the S205 apoenzyme and the binary complexes with NAD+ of both isoforms were determined. (
  • The crystal structures of the syn1- and anti1-mouse AChE complexes at 2.45- to 2.65-A resolution reveal not only substantial binding contributions from the triazole moieties, but also that binding of the syn1 isomer induces large and unprecedented enzyme conformational changes not observed in the anti1 complex nor predicted from structures of the apoenzyme and complexes with the precursor reactants. (
  • Coenzymes bind to the apoenzyme and assist in enzyme activity. (
  • The HCV NS5B apoenzyme structure reported here can accommodate a template:primer duplex without global conformational changes, supporting the hypothesis that this structure is essentially preserved during the reaction pathway. (
  • Kwon YC, Oh IS, Lee N, Lee KH, Yoon YJ, Lee EY, Kim BG, and Kim DM (2013) Integrating cell-free biosyntheses of heme prosthetic group and apoenzyme for the synthesis of functional P450 monooxygenase. (
  • Cytosine potently inhibited reconstitution of the apoenzyme with Fe2+. (
  • Acquaviva C, Benoist JF, Pereira S, Callebaut I, Koskas T, Porquet D, Elion J. Molecular basis of methylmalonyl-CoA mutase apoenzyme defect in 40 European patients affected by mut(o) and mut- forms of methylmalonic acidemia: identification of 29 novel mutations in the MUT gene. (
  • they include decreased intake, impaired absorption and use, increased demand, and possibly an apoenzyme defect. (
  • The periplasmic region shows the orientation of the catalytic domain of the SPase apoenzyme (PDB 1kn9) in the membrane, calculated based on a computational approach. (
  • Fe2+ was efficiently removed from the enzyme with o-phenanthroline to yield an apoenzyme with less than 5% of the catalytic activity of native enzyme. (
  • Here, TDH from Clostridium difficile has been cloned and overexpressed, and the X-ray structure of the apoenzyme form has been determined at 2.6 Å resolution. (
  • Working with the lab of Seigo Shima at the Max Planck Institute for Terrestrial Microbiology, Hu's lab has now synthesized a manganese-hydrogenase by incorporating a manganese complex into the apoenzyme (the active-site free part) of iron-hydrogenase. (