Abstract |
A deletion of the sigB operon was constructed in three genetically distinct Staphylococcus aureus strains, and the phenotypes of the resulting mutants were analyzed. Compared to the corresponding wild-type strains, the DeltasigB mutants showed reduced pigmentation, accelerated sedimentation, and increased sensitivity to hydrogen peroxide during the stationary growth phase. A cytoplasmic protein missing in the DeltasigB mutants was identified as alkaline shock protein 23, and an extracellular protein excreted at higher levels in one of the DeltasigB mutants was identified as staphylococcal thermonuclease. Interestingly, most sigB deletion phenotypes were only seen in S. aureus COL and Newman and not in 8325, which was found to contain an 11-bp deletion in the regulator gene rsbU. Taken together, our results show that sigmaB is a global regulator which modulates the expression of several virulence factors in S. aureus and that laboratory strain 8325 is a sigmaB-defective mutant.
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Authors | I Kullik, P Giachino, T Fuchs |
Journal | Journal of bacteriology
(J Bacteriol)
Vol. 180
Issue 18
Pg. 4814-20
(Sep 1998)
ISSN: 0021-9193 [Print] United States |
PMID | 9733682
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)
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Chemical References |
- Bacterial Proteins
- SigB protein, Bacteria
- Sigma Factor
- Hydrogen Peroxide
- Lipase
- Micrococcal Nuclease
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Topics |
- Bacterial Proteins
(genetics, physiology)
- Gene Expression Regulation, Bacterial
- Genes, Bacterial
- Hydrogen Peroxide
(pharmacology)
- Lipase
(metabolism)
- Micrococcal Nuclease
(metabolism)
- Pigmentation
- Sigma Factor
(genetics, physiology)
- Staphylococcus aureus
(genetics, pathogenicity)
- Virulence
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