Kinetically trapped metastable intermediate of a disulfide-deficient mutant of the starch-binding domain of glucoamylase.

ABSTRACT: Refolding of a thermally unfolded disulfide-deficient mutant of the starch-binding domain of glucoamylase was investigated using differential scanning calorimetry, isothermal titration calorimetry, CD, and (1)H NMR. When the protein solution was rapidly cooled from a higher temperature, a kinetic intermediate was formed during refolding. The intermediate was unexpectedly stable compared with typical folding intermediates that have short half-lives. It was shown that this intermediate contained substantial secondary structure and tertiary packing and had the same binding ability with beta-cyclodextrin as the native state, suggesting that the intermediate is highly-ordered and native-like on the whole. These characteristics differ from those of partially folded intermediates such as molten g

SUBMITTER: Sugimoto H 

PROVIDER: S-EPMC2776959 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature