title: Significance of Cys-153 for the phosphatase activity of glyceraldehyde-3-phosphate dehydrogenase.
abstract: After oxidation of the catalytically active sulfhydryl group of Cys-149, glyceraldehyde-3 phosphate dehydrogenase is known to acquire an acylphosphatase activity. Modification of one cysteine residue, obviously Cys-153, with p-mercuribenzoate or N-ethylmaleimide fully inactivates the phosphatase activity of the oxidized enzyme suggesting that this amino acid residue is involved in the reaction. An acyl transfer between Cys-153 and the sulfenic acid derivative of Cys-149 in the mechanism of the phosphatase reaction could explain the data obtained. Compounds which contain heteroatoms at two adjacent carbon atoms such as alpha-amino acids, peptides, EDTA and o-phenanthroline are shown to inhibit the phosphatase reaction of glyceraldehyde-3-phosphate dehydrogenase. These compounds bind in the active centre region close to Cys-153 and may interfere with the acyl transfer reaction thus inhibing the overall phosphatase reaction.
mesh_terms: D017766:Acid Anhydride Hydrolases; D000818:Animals; D001224:Aspartic Acid / Q000494:pharmacology; D003553:Cystine / Q000378:metabolism*; D004492:Edetic Acid / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D005998:Glycine / Q000494:pharmacology; D008024:Ligands; D009243:NAD / Q000378:metabolism; D010618:Phenanthrolines / Q000494:pharmacology; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D013552:Swine; D000097024:Acylphosphatase
chemical_list: D017766:Acid Anhydride Hydrolases; D001224:Aspartic Acid; D003553:Cystine; D004492:Edetic Acid; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D005998:Glycine; D008024:Ligands; D009243:NAD; D010618:Phenanthrolines; D010744:Phosphoric Monoester Hydrolases; D000097024:Acylphosphatase; C025205:1,10-phenanthroline