Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: KEGG:D02011 (FAD)
 5,530 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pseudomonas L-phenylalanine oxidase (deaminating and decarboxylating) contains two FAD molecules in one molecule of the enzyme (Koyama, H. (1983) J. Biochem. 93, 1313-1319). When the enzyme was mixed anaerobically with L-phenylalanine, beta-2-thienylalanine, L-tyrosine, or L-methionine, a spectral species (purple intermediate) with a broad absorption band around 540 nm was observed with each substrate, and decayed slowly. From the data on the overall reaction kinetics, the rate of the L-phenylalanine oxidase reaction was expressed as follows. e/v = e/Vm + A/[S] + B/[O2] where e represents the concentration of enzyme unit, v the rate of the overall reaction, Vm the maximum velocity, and A and B are constants. Furthermore, the reactions of the enzyme with beta-2-thienylalanine (mostly an oxygenase substrate) and L-methionine (an oxidase substrate) were analyzed by the "stopped flow" method. The following scheme for the mechanism of L-phenylalanine oxidase reaction with both substrates is proposed, based on the data obtained. (formula; see text) Where Eox represents the oxidized form of the enzyme unit, EoxS the enzyme unit (oxidized form)-substrate compound, X the purple intermediate with a characteristic broad absorption band around 540 nm, S the substrate and P the product.
 ...
PMID:Spectral and kinetic studies on Pseudomonas L-phenylalanine oxidase (deaminating and decarboxylating). 381 66

L-Lysine alpha-oxidase from Trichoderma viride Y244-2 has been purified to homogeneity. The enzyme shows absorption maxima at 277, 388, and 466 nm and a shoulder around 490 nm and contains 2 mol of FAD/mol of enzyme. The enzyme has a molecular weight of approximately 116,000 and consists of two subunits identical in molecular weight (about 56,000). In addition to L-lysine, L-ornithine, L-phenylalanine, L-tyrosine, L-arginine, and L-histidine are oxidized by the enzyme to a lesser extent. Several lysine analogs such as delta-hydroxylysine are oxidized efficiently. Balance studies showed that 1 mol of L-lysine is converted to an equimolar amount of alpha-keto-epsilon-aminocaproate, ammonia, and hydrogen peroxide with the consumption of 1 mol of oxygen. alpha-Keto-epsilon-aminocaproate spontaneously is dehydrated intramolecularly into delta 1-piperideine-2-carboxylate in the presence of catalase, and is oxidatively decarboxylated into delta-aminovalerate in the absence of catalase. The Michaelis constants are as follows: 0.04 mM for L-lysine, 0.44 mM for L-ornithine, 14 mM for L-phenylalanine, and 1.6 mM for oxygen with L-lysine.
 ...
PMID:A new antitumor enzyme, L-lysine alpha-oxidase from Trichoderma viride. Purification and enzymological properties. 610 34

8 alpha-(O-Tyrosyl)riboflavin has been synthesized by condensation of the copper complex of L-tyrosine with 8 alpha-bromotetraacetylriboflavin. The structure of this synthetic product was proven by absorption and 1H NMR spectroscopy and by chemical degradation, which yielded 1 mol of tyrosine per mol of flavin. The synthetic compound comigrated wtih the (aminoacyl)riboflavin isolated from the p-cresol methylhydroxylase of Pseudomonas putida, and both showed identical absorption and fluorescence spectral properties. 8 alpha-(O-Tyrosyl)riboflavin as well as the flavin-containing decapeptide from p-cresol methylhydroxylase undergoes reductive cleavage to form riboflavin and FAD, respectively, on anaerobic treatment with dithionite. In contrast, the native enzyme, on reduction with dithionite, yields a reduced flavin via a red (anionic) flavosemiquinone intermediate, which remains covalently bound to the protein even under denaturing conditions. 8 alpha-(O-Tyrosyl)riboflavin bound to apoflavodoxin is also not cleaved on reduction with dithionite, but, instead, a blue (neutral) semiquinone of tyrosylriboflavin is generated, which is resistant to further reduction with dithionite. Three p-cresol methylhydroxylases, isolated from different strains of Pseudomonas putida, differing in molecular weight and Km values for substrates, contain the same peptide at the flavin site. These data provide definitive proof for the existence of 8 alpha-(O-tyrosyl)riboflavin in nature.
 ...
PMID:8 alpha-(O-Tyrosyl)flavin adenine dinucleotide, the prosthetic group of bacterial p-cresol methylhydroxylase. 724 67