Heat-treated γ-glutamyltranspeptidase of Escherichia coli recovered enzymatic activity after incubation at 4 °C, while heat-treated γ-glutamyltranspeptidase of Bacillus subtilis did not. Fluorescent spectra, CD spectra, and native polyacrylamide gel electrophoresis analysis suggested that the dimer of E. coli γ-glutamyltranspeptidase was separated into protomers by heat-treatment, but was renatured by incubation at 4 °C.
