1fpo
From Proteopedia
HSC20 (HSCB), A J-TYPE CO-CHAPERONE FROM E. COLI
Overview
Hsc20 is a 20 kDa J-protein that regulates the ATPase activity and peptide-binding specificity of Hsc66, an hsp70-class molecular chaperone. We report herein the crystal structure of Hsc20 from Escherichia coli determined to a resolution of 1.8 A using a combination of single isomorphous replacement (SIR) and multi-wavelength anomalous diffraction (MAD). The overall structure of Hsc20 consists of two distinct domains, an N-terminal J-domain containing residues 1-75 connected by a short loop to a C-terminal domain containing residues 84-171. The structure of the J-domain, involved in interactions with Hsc66, resembles the alpha-topology of J-domain fragments of Escherichia coli DnaJ and human Hdj1 previously determined by solution NMR methods. The C-terminal domain, implicated in binding and targeting proteins to Hsc66, consists of a three-helix bundle in which two helices comprise an anti-parallel coiled-coil. The two domains make contact through an extensive hydrophobic interface ( approximately 650 A(2)) suggesting that their relative orientations are fixed. Thus, Hsc20, in addition to its role in the regulation of the ATPase activity of Hsc66, may also function as a rigid scaffold to facilitate positioning of the protein substrates targeted to Hsc66.
About this Structure
1FPO is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of Hsc20, a J-type Co-chaperone from Escherichia coli., Cupp-Vickery JR, Vickery LE, J Mol Biol. 2000 Dec 15;304(5):835-45. PMID:11124030 Page seeded by OCA on Fri May 2 16:37:01 2008
