Alkylation of 6-phosphogluconate dehydrogenase from Candida utilis with coenzyme analogues.
The mechanism of the inactivation of 6-phosphogluconate dehydrogenase from Candida utilis with two coenzyme analogues can be differentiated on the basis of kinetic studies and of the properties of the inactivated enzyme. 3-Chloroacetylpyridine--adenine dinucleotide phosphate is clearly an affinity label and 3-choloroacetylpyridine--adenine dinucleotide a second-order reagent. For 3-chloroacetylpyridine--adenine dinucleotide phosphate, there is a loss of one thiol per subunit at complete inactivation whereas for 3-chloroacetylpyridine--adenine dinucleotide 2.7 thiol groups are lost. The fluorescence of the protein is quenched after alkylation by 3-chloroacetylpyridine--adenine dinucleotide phosphate and there is no quenching after the inactivation with 3-chloroacetylpyridine--adenine dinucleotide.
D000478:Alkylation; D002175:Candida / Q000201:enzymology*; D007700:Kinetics; D009249:NADP / Q000031:analogs & derivatives*; D010734:Phosphogluconate Dehydrogenase / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
D009249:NADP; D010734:Phosphogluconate Dehydrogenase