Structural highlights
Function
[SIGE_SALTY] Molecular chaperone required for SopB/SigD stabilization and secretion.[1] [2]
Publication Abstract from PubMed
Several Gram-negative bacterial pathogens have evolved a type III secretion system to deliver virulence effector proteins directly into eukaryotic cells, a process essential for disease. This specialized secretion process requires customized chaperones specific for particular effector proteins. The crystal structures of the enterohemorrhagic Escherichia coli O157:H7 Tir-specific chaperone CesT and the Salmonella enterica SigD-specific chaperone SigE reveal a common overall fold and formation of homodimers. Site-directed mutagenesis suggests that variable, delocalized hydrophobic surfaces observed on the chaperone homodimers are responsible for specific binding to a particular effector protein. Isothermal titration calorimetry studies of Tir-CesT and enzymatic activity profiles of SigD-SigE indicate that the effector proteins are not globally unfolded in the presence of their cognate chaperones.
Structural and biochemical characterization of the type III secretion chaperones CesT and SigE.,Luo Y, Bertero MG, Frey EA, Pfuetzner RA, Wenk MR, Creagh L, Marcus SL, Lim D, Sicheri F, Kay C, Haynes C, Finlay BB, Strynadka NC Nat Struct Biol. 2001 Dec;8(12):1031-6. PMID:11685226[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Hong KH, Miller VL. Identification of a novel Salmonella invasion locus homologous to Shigella ipgDE. J Bacteriol. 1998 Apr;180(7):1793-802. PMID:9537377
- ↑ Darwin KH, Robinson LS, Miller VL. SigE is a chaperone for the Salmonella enterica serovar Typhimurium invasion protein SigD. J Bacteriol. 2001 Feb;183(4):1452-4. PMID:11157959 doi:http://dx.doi.org/10.1128/JB.183.4.1452-1454.2001
- ↑ Luo Y, Bertero MG, Frey EA, Pfuetzner RA, Wenk MR, Creagh L, Marcus SL, Lim D, Sicheri F, Kay C, Haynes C, Finlay BB, Strynadka NC. Structural and biochemical characterization of the type III secretion chaperones CesT and SigE. Nat Struct Biol. 2001 Dec;8(12):1031-6. PMID:11685226 doi:10.1038/nsb717
