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Small noncoding RNA GcvB is a novel regulator of acid resistance in Escherichia coli.

ABSTRACT:

Background

The low pH environment of the human stomach is lethal for most microorganisms; but not Escherichia coli, which can tolerate extreme acid stress. Acid resistance in E. coli is hierarchically controlled by numerous regulators among which are small noncoding RNAs (sncRNA).

Results

In this study, we individually deleted seventy-nine sncRNA genes from the E. coli K12-MG1655 chromosome, and established a single-sncRNA gene knockout library. By systematically screening the sncRNA mutant library, we show that the sncRNA GcvB is a novel regulator of acid resistance in E. coli. We demonstrate that GcvB enhances the ability of E. coli to survive low pH by upregulating the levels of the alternate sigma factor RpoS.

Conclusion

GcvB positively regulates acid resistance by affecting RpoS expression. These data advance our understanding of the sncRNA regulatory network involved in modulating acid resistance in E. coli.

SUBMITTER: Jin Y

PROVIDER: S-EPMC2676305 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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Small noncoding RNA GcvB is a novel regulator of acid resistance in Escherichia coli.

Jin Ye Y Watt Rory M RM Danchin Antoine A Huang Jian-dong JD

BMC genomics 20090420

<h4>Background</h4>The low pH environment of the human stomach is lethal for most microorganisms; but not Escherichia coli, which can tolerate extreme acid stress. Acid resistance in E. coli is hierarchically controlled by numerous regulators among which are small noncoding RNAs (sncRNA).<h4>Results</h4>In this study, we individually deleted seventy-nine sncRNA genes from the E. coli K12-MG1655 chromosome, and established a single-sncRNA gene knockout library. By systematically screening the snc ...[more]

PMID: 19379489

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