An Essential Histidine in the Catalytic Activities of 3-Phosphoglyceraldehyde Dehydrogenase

摘要: Abstract Photooxidation of 3-phosphoglyceraldehyde dehydrogenase in the presence rose bengal did not effect rate or extent acetylation enzyme with p-nitrophenyl acetate; however, deacetylation S-acetyl-enzyme was selectively inhibited by 50 to 60%. Amino acid analysis photooxidized showed about 1 histidine residue per monomer destroyed. No other changes amino content were found. Peptide mapping studies that a specific photooxidized. The sequence tetradecapeptide containing photosensitive is as follows: Val-Asp-Val-Val-Ala-Ile-Asn-Asp(Pro,Phe)Ile-Asp-Leu-His also oxidation 60% suggesting involved principal physiological reaction carried out enzyme. At high dye ratios, dark esterase and activities. Rose competitive inhibitor respect DPN arsenate, but noncompetitive acetate. effects photooxidation produced permanent change whereas inhibitions completely reversed removal from surface charcoal treatment. role various reactions catalyzed discussed.