4FEI

Hsp17.7 from Deinococcus radiodurans

Summary for 4FEI

• Entry DOI: 10.2210/pdb4fei/pdb
• Related: 1GME 1SHS 2WJ7 3GLA
• Descriptor: Heat shock protein-related protein (2 entities in total)
• Functional Keywords: stress response, alpha-crystallin domain fold, aggregates, cytosol, chaperone
• Biological source: Deinococcus radiodurans
• Total number of polymer chains: 1
• Total formula weight: 10736.01

Authors

Bepperling, A.,Alte, F.,Kriehuber, T.,Braun, N.,Weinkauf, S.,Groll, M.,Haslbeck, M.,Buchner, J. (deposition date: 2012-05-30, release date: 2012-12-26, Last modification date: 2023-11-08)

Primary citation

Bepperling, A.,Alte, F.,Kriehuber, T.,Braun, N.,Weinkauf, S.,Groll, M.,Haslbeck, M.,Buchner, J.
Alternative bacterial two-component small heat shock protein systems.
Proc.Natl.Acad.Sci.USA, 109:20407-20412, 2012

PubMed Abstract: Small heat shock proteins (sHsps) are molecular chaperones that prevent the aggregation of nonnative proteins. The sHsps investigated to date mostly form large, oligomeric complexes. The typical bacterial scenario seemed to be a two-component sHsps system of two homologous sHsps, such as the Escherichia coli sHsps IbpA and IbpB. With a view to expand our knowledge on bacterial sHsps, we analyzed the sHsp system of the bacterium Deinococcus radiodurans, which is resistant against various stress conditions. D. radiodurans encodes two sHsps, termed Hsp17.7 and Hsp20.2. Surprisingly, Hsp17.7 forms only chaperone active dimers, although its crystal structure reveals the typical α-crystallin fold. In contrast, Hsp20.2 is predominantly a 36mer that dissociates into smaller oligomeric assemblies that bind substrate proteins stably. Whereas Hsp20.2 cooperates with the ATP-dependent bacterial chaperones in their refolding, Hsp17.7 keeps substrates in a refolding-competent state by transient interactions. In summary, we show that these two sHsps are strikingly different in their quaternary structures and chaperone properties, defining a second type of bacterial two-component sHsp system.

PubMed: 23184973
DOI: 10.1073/pnas.1209565109

Experimental method

X-RAY DIFFRACTION (2.4 Å)