Open AccessKinetics of inactivation of glutamate decarboxylase by cysteine-specific reagents.
Author(s) -
Sara J. McCormick,
G. Tunnicliff
Publication year - 2001
Publication title -
acta biochimica polonica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.452
H-Index - 78
eISSN - 1734-154X
pISSN - 0001-527X
DOI - 10.18388/abp.2001_3940
Subject(s) - chemistry , cysteine , reagent , substrate (aquarium) , enzyme , escherichia coli , biochemistry , cofactor , kinetics , thiol , glutamate decarboxylase , reaction rate constant , stereochemistry , organic chemistry , biology , ecology , physics , quantum mechanics , gene
Mercuric chloride, p-chloromercuribenzoate and 5,5'-dithiobis(2-nitrobenzoic acid) irreversibly inhibited the activity of Escherichia coli glutamate decarboxylase. Their second order rate constants for inactivation are 0.463 microM(-1) min(-1), 0.034 microM(-1) min(-1), 0.018 microM(-1) min(-1), respectively. The characteristics of the inhibition by the three thiol-group reagents supports the idea that cysteinyl residues at the binding sites for the cofactor and/or the substrate are important for enzyme activity in E. coli.