PH-dependent conformational changes in bacterial Hsp90 reveal a Grp94-like conformation at pH 6 that is highly active in suppression of citrate synthase aggregation.

ABSTRACT: The molecular chaperone Hsp90 depends upon large conformational rearrangements for its function. One driving force for these rearrangements is the intrinsic ATPase activity of Hsp90, as seen with other chaperones. However, unlike other chaperones, structural and kinetic studies have shown that the ATPase cycle of Hsp90 is not conformationally deterministic. That is, rather than dictating the conformational state, ATP binding and hydrolysis shift the equilibrium between a preexisting set of conformational states in an organism-dependent manner. While many conformations of Hsp90 have been described, little is known about how they relate to chaperone function. In this study, we show that the conformational equilibrium of the bacterial Hsp90, HtpG, can be shifted with pH. Using small-angle X-r

SUBMITTER: Krukenberg KA 

PROVIDER: S-EPMC2735500 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature