2012年3月29日 · DnaK, the major bacterial Hsp70, is one of the most abundant constitutively expressed and stress inducible chaperones in the E. coli cytosol. Yet it is not essential under nonstress conditions at intermediate temperature (Bukau and Walker, 1989).

Mycoplasma heat shock proteins include homologs of two of the most broadly conserved heat shock proteins, DnaK and GroEL. Both of these proteins are involved in protein folding functions and are essential for cell survival.

2024年11月3日 · We investigated the roles of the DnaK (Hsp70), DnaJ and GrpE chaperones of Escherichia coli in prevention and repair of thermally induced protein damage using firefly luciferase as a test substrate.

2024年1月22日 · Here we report a cryo-EM analysis of GrpE bound to an intact Mtb DnaK, revealing an asymmetric 1:2 DnaK−GrpE complex. The GrpE dimer ratchets to modulate both DnaK nucleotide-binding domain and...

2019年6月28日 · All Hsp70 family members share at least two of the four structural features of the archetype Hsp70, the bacterial DnaK: an N-terminal, 45-kDa nucleotide binding domain (NBD), followed by a 15-kDa...

The DnaK (Hsp70), DnaJ, and GrpE heat shock proteins of Escherichia coli constitute a cellular chaperone system for protein folding. Substrate interactions are controlled by the ATPase activity of DnaK which itself is regulated by the nucleotide exchange factor GrpE.

DnaK proteins contain a hydrophobic patch (L257-V59 of DnaK) at the top of the cleft and two putative salt bridges (E264-R56, upper; E267-K55, lower) that are mainly responsible for the polarity of the interface.

2022年3月3日 · DnaK is a highly conserved protein belonging to the heat-shock protein 70 family of molecular chaperones, which plays important roles as a moonlighting protein in various bacteria. In the present study, we identified the surface exposure of M. hyorhinis DnaK.

We investigated the interaction of the major inducible hsp from mammalian (Hsp70) and bacterial (DnaK) species with liposomes. We found that mammalian Hsp70 displayed a high specificity for negatively charged phospholipids, such as phosphatidyl serine, whereas DnaK interacted with all lipids tested regardless of the charge.

2025年3月18日 · DnaK operates within a network of co-chaperones that regulate its activity. The most prominent are DnaJ and GrpE, which influence its ATPase cycle and substrate binding. DnaJ, an Hsp40 family member, recognizes misfolded polypeptides and delivers them to DnaK. By binding exposed hydrophobic regions, DnaJ stimulates DnaK’s ATP hydrolysis ...