PMID: 12205096 , Related PDB ids: 1K6K, 1KSF

Authors:

Guo F, Maurizi MR, Esser L, Xia D

Title:

Crystal structure of ClpA, an Hsp100 chaperone and regulator of ClpAP protease.

Journal:

J Biol Chem. 2002 Nov 29;277(48):46743-52. Epub 2002 Aug 29.

Abstract:

Escherichia coli ClpA, an Hsp100/Clp chaperone and an integral component of the ATP-dependent ClpAP protease, participates in regulatory protein degradation and the dissolution and degradation of protein aggregates. The crystal structure of the ClpA subunit reveals an N-terminal domain with pseudo-twofold symmetry and two AAA(+) modules (D1 and D2) each consisting of a large and a small sub-domain with ADP bound in the sub-domain junction. The N-terminal domain interacts with the D1 domain in a manner similar to adaptor-binding domains of other AAA(+) proteins. D1 and D2 are connected head-to-tail consistent with a cooperative and vectorial translocation of protein substrates. In a planar hexamer model of ClpA, built by assembling ClpA D1 and D2 into homohexameric rings of known structures of AAA(+) modules, the differences in D1-D1 and D2-D2 interfaces correlate with their respective contributions to hexamer stability and ATPase activity.