Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.8.1.4 (diaphorase)
 2,754 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The rabbits being repeatedly poisoned with small doses of sodium cyanide, the activity of succinic dehydrogenase in the tissues does not essentially change. The activity of NAD.H2-cytochrome-c-reductase and NAD.H2-diaphorase in the brain, myocardium and kidneys increases. Under histotoxic hypoxia the level of iron in the tissues increases by 52-93%, that of copper--by 28-36%, of zinc--by 21-74% and of cobalt by 28-40%. There existed a positive correlation between the content of iron and the activity of NAD-dependent enzymes. In nonlethal form of histotoxic hypoxia the content of nonhemin iron and the activity of NAD.H2-cytochrome-c-reductase in the mitochondria of the brain increases by 25% and 17%, respectively, and a direct correlation is revealed between them.
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PMID:[Iron, copper, zinc and cobalt content and activity of respiratory metalloenzymes in animal tissues under toxic hypoxia]. 68 69

Covalent modifications of proteins by endogenous reactive nitrogen oxide species lead to cytotoxic effects that are implicated in diseases associated with chronic infections and inflammation. Tyrosine nitration is a major post-translational modification of proteins by reactive nitrogen oxide species. Recent studies suggest that nitrotyrosine is not a permanent protein modification. We previously demonstrated that lipoyl dehydrogenase is capable of converting 3-nitrotyrosine into 3-aminotyrosine in the presence of certain reducing agents. In this study, we compared the abilities of various hemoproteins, hemin, and the cobalt-containing cofactor cyanocobalamin to mediate H(2)O(2)/nitrite-dependent tyrosine nitration and found that these hemoproteins and metal-containing cofactors also catalyzed the reduction of 3-nitrotyrosine to various extents in the presence of thiol reducing agents or ascorbate. The H(2)O(2)/nitrite-induced post-translational modifications of human hemoglobin identified by nanoLC/nanospray ionization tandem mass spectrometric analysis of the tryptic digest include nitration of tyrosine and tryptophan, as well as oxidation of methionine and cysteine residues. Nitration of human hemoglobin by H(2)O(2)/nitrite was detected on Tyr24 and Tyr42 (alpha-chain) and on Tyr130 and Trp15 (beta-chain) in the alphabeta-dimer. Oxidation of methionine and cysteine residues was also observed. Furthermore, hemoglobin also catalyzed nitro reduction of 3-nitrotyrosine to form 3-aminotyrosine, at Tyr24 in the alpha-chain peptide of human Hb in the presence of ascorbate. The enhanced peroxidase activity of nitrated hemoglobin can be reversed by the antioxidant ascorbate. These results suggest a possible in vivo pathway for hemoglobin contributing to denitration of nitrated proteins through redox regulation.
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PMID:H2O2/nitrite-induced post-translational modifications of human hemoglobin determined by mass spectrometry: redox regulation of tyrosine nitration and 3-nitrotyrosine reduction by antioxidants. 1816 31