Abstract
Saccharomyces cerevisiae Hsp33/YOR391Cp is a member of the ThiI/DJ-1/PfpI superfamily. Hsp33 was overexpressed in Escherichia coli and its crystal structure was determined at 2.40 Å resolution. Structural comparison revealed that Hsp33 adopts an α/β-hydrolase fold and possesses the putative Cys-His-Glu catalytic triad common to the Hsp31 family, suggesting that Hsp33 and Hsp31 share similar aminopeptidase activity, while structural deviations in helices α2-α3 of the core domain might be responsible for the access of different peptide substrates.