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Identification and characterization of gsp65, an organic hydroperoxide resistance (ohr) gene encoding a general stress protein in Enterococcus faecalis.

ABSTRACT: The Enterococcus faecalis general stress protein Gsp65 has been purified from two-dimensional gel electrophoresis. Determination of its N-terminal sequence and characterization of the corresponding gene revealed that the gsp65 product is a 133-amino-acid protein sharing homologies with organic hydroperoxide resistance (Ohr) proteins. Transcriptional analysis of gsp65 gave evidence for a monocistronic mRNA initiated 52 nucleotides upstream of the ATG start codon and for an induction in response to hydrogen peroxide, heat shock, acid pH, detergents, ethanol, sodium chloride, and tert-butylhydroperoxide (tBOOH). A gsp65 mutant showed increased sensitivity to the organic hydroperoxide tBOOH and to ethanol.

SUBMITTER: Rince A

PROVIDER: S-EPMC95027 | biostudies-literature | 2001 Feb

REPOSITORIES: biostudies-literature

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Identification and characterization of gsp65, an organic hydroperoxide resistance (ohr) gene encoding a general stress protein in Enterococcus faecalis.

Rincé A A Giard J C JC Pichereau V V Flahaut S S Auffray Y Y

Journal of bacteriology 20010201 4

The Enterococcus faecalis general stress protein Gsp65 has been purified from two-dimensional gel electrophoresis. Determination of its N-terminal sequence and characterization of the corresponding gene revealed that the gsp65 product is a 133-amino-acid protein sharing homologies with organic hydroperoxide resistance (Ohr) proteins. Transcriptional analysis of gsp65 gave evidence for a monocistronic mRNA initiated 52 nucleotides upstream of the ATG start codon and for an induction in response t ...[more]

PMID: 11157966

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