3PRB

Structural analysis of protein folding by the Methanococcus jannaschii chaperone FKBP26

Summary for 3PRB

• Entry DOI: 10.2210/pdb3prb/pdb
• Related: 3PR9 3PRA 3PRD
• Descriptor: FKBP-type peptidyl-prolyl cis-trans isomerase (2 entities in total)
• Functional Keywords: fkbp, chaperone, isomerase
• Biological source: Methanocaldococcus jannaschii (Methanococcus jannaschii)
• Total number of polymer chains: 2
• Total formula weight: 51974.69

Authors

Martinez-Hackert, E.,Hendrickson, W.A. (deposition date: 2010-11-29, release date: 2011-01-19, Last modification date: 2024-02-21)

Primary citation

Martinez-Hackert, E.,Hendrickson, W.A.
Structural Analysis of Protein Folding by the Long-Chain Archaeal Chaperone FKBP26.
J.Mol.Biol., 407:450-464, 2011

PubMed Abstract: In the cell, protein folding is mediated by folding catalysts and chaperones. The two functions are often linked, especially when the catalytic module forms part of a multidomain protein, as in Methanococcus jannaschii peptidyl-prolyl cis/trans isomerase FKBP26. Here, we show that FKBP26 chaperone activity requires both a 50-residue insertion in the catalytic FKBP domain, also called 'Insert-in-Flap' or IF domain, and an 80-residue C-terminal domain. We determined FKBP26 structures from four crystal forms and analyzed chaperone domains in light of their ability to mediate protein-protein interactions. FKBP26 is a crescent-shaped homodimer. We reason that folding proteins are bound inside the large crescent cleft, thus enabling their access to inward-facing peptidyl-prolyl cis/trans isomerase catalytic sites and ipsilateral chaperone domain surfaces. As these chaperone surfaces participate extensively in crystal lattice contacts, we speculate that the observed lattice contacts reflect a proclivity for protein associations and represent substrate interactions by FKBP26 chaperone domains. Finally, we find that FKBP26 is an exceptionally flexible molecule, suggesting a mechanism for nonspecific substrate recognition.

PubMed: 21262232
DOI: 10.1016/j.jmb.2011.01.027

Experimental method

X-RAY DIFFRACTION (2.2 Å)