PMID:22296329

Citation	Wholey, WY and Jakob, U (2012) Hsp33 confers bleach resistance by protecting elongation factor Tu against oxidative degradation in Vibrio cholerae. Mol. Microbiol. 83:981-91
Abstract	The redox-regulated chaperone Hsp33 protects bacteria specifically against stress conditions that cause oxidative protein unfolding, such as treatment with bleach or exposure to peroxide at elevated temperatures. To gain insight into the mechanism by which expression of Hsp33 confers resistance to oxidative protein unfolding conditions, we made use of Vibrio cholerae strain O395 lacking the Hsp33 gene hslO. We found that this strain, which is exquisitely bleach-sensitive, displays a temperature-sensitive (ts) phenotype during aerobic growth, implying that V. cholerae suffers from oxidative heat stress when cultivated at 43°C. We utilized this phenotype to select for Escherichia coli genes that rescue the ts phenotype of V. cholerae ΔhslO when overexpressed. We discovered that expression of a single protein, the elongation factor EF-Tu, was sufficient to rescue both the ts and bleach-sensitive phenotypes of V. cholerae ΔhslO. In vivo studies revealed that V. cholerae EF-Tu is highly sensitive to oxidative protein degradation in the absence of Hsp33, indicating that EF-Tu is a vital chaperone substrate of Hsp33 in V. cholerae. These results suggest an 'essential client protein' model for Hsp33's chaperone action in Vibrio in which stabilization of a single oxidative stress-sensitive protein is sufficient to enhance the oxidative stress resistance of the whole organism.
Links	PubMed PMC3288485 Online version:10.1111/j.1365-2958.2012.07982.x
Keywords	Bacterial Proteins/genetics; Bacterial Proteins/metabolism; Escherichia coli/metabolism; Escherichia coli Proteins/metabolism; Heat-Shock Proteins/genetics; Heat-Shock Proteins/metabolism; Heat-Shock Response; Molecular Chaperones/genetics; Molecular Chaperones/metabolism; Oxidative Stress; Peptide Elongation Factor Tu/metabolism; Proteolysis; Sodium Hypochlorite/pharmacology; Vibrio cholerae/drug effects; Vibrio cholerae/genetics; Vibrio cholerae/metabolism
edit table

Annotations

Gene product	Qualifier	GO Term	Evidence Code	with/from	Aspect	Extension	Notes	Status
VIBCH:HSLO		GO:0051082: unfolded protein binding	ECO:0000315:		F		Figure 3D. Results indicate EF-Tu was degraded faster in the hslO deletion strain than in wild-type cells. Hsp33 protects EF-Tu against protein degradation by acting as a chaperone.	complete CACAO 4001

References

See Help:References for how to manage references in GONUTS.