Inactivation and unfolding of protein tyrosine phosphatase from Thermus thermophilus HB27 during urea and guanidine hydrochloride denaturation.

ABSTRACT: The effects of urea and guanidine hydrochloride (GdnHCl) on the activity, conformation and unfolding process of protein tyrosine phosphatase (PTPase), a thermostable low molecular weight protein from Thermus thermophilus HB27, have been studied. Enzymatic activity assays showed both urea and GdnHCl resulted in the inactivation of PTPase in a concentration and time-dependent manner. Inactivation kinetics analysis suggested that the inactivation of PTPase induced by urea and GdnHCl were both monophasic and reversible processes, and the effects of urea and GdnHCl on PTPase were similar to that of mixed-type reversible inhibitors. Far-ultraviolet (UV) circular dichroism (CD), Tryptophan and 1-anilinonaphthalene -8-sulfonic acid (ANS) fluorescence spectral analyses indicated the existence of a

SUBMITTER: Wang Y 

PROVIDER: S-EPMC4177882 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature