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Isolation, characterization, and sequence of an Escherichia coli heat shock gene, htpX.

ABSTRACT: We isolated and characterized a new Escherichia coli gene, htpX. The htpX gene has been localized at min 40.3 on the chromosome. We determined its transcription and translation start site. htpX expresses a 32-kDa protein from a monocistronic transcript; expression of this protein is induced by temperature upshift. htpX is expressed from a sigma 32-dependent promoter and is thus part of the heat shock regulon. Cells carrying a htpX gene disruption grow well at all temperatures and under all conditions tested and have no apparent phenotype. However, cells which overexpress a truncated form of the protein display a higher rate of degradation of puromycyl peptides.

SUBMITTER: Kornitzer D

PROVIDER: S-EPMC207877 | biostudies-other | 1991 May

REPOSITORIES: biostudies-other

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Isolation, characterization, and sequence of an Escherichia coli heat shock gene, htpX.

Kornitzer D D Teff D D Altuvia S S Oppenheim A B AB

Journal of bacteriology 19910501 9

We isolated and characterized a new Escherichia coli gene, htpX. The htpX gene has been localized at min 40.3 on the chromosome. We determined its transcription and translation start site. htpX expresses a 32-kDa protein from a monocistronic transcript; expression of this protein is induced by temperature upshift. htpX is expressed from a sigma 32-dependent promoter and is thus part of the heat shock regulon. Cells carrying a htpX gene disruption grow well at all temperatures and under all condi ...[more]

PMID: 1826904

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