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In vivo supercoiling of plasmid and chromosomal DNA in an Escherichia coli hns mutant.

ABSTRACT: We have used trimethylpsoralen to measure localized levels of unconstrained DNA supercoiling in vivo. The data provide direct evidence that plasmid and chromosomal DNA supercoiling is altered in vivo in an hns mutant. This increase in supercoiling is independent of transcription or changes in the activity of topoisomerase I. These data have implications for the mechanisms by which the chromatin-associated protein H-NS may influence chromosome organization and gene expression.

SUBMITTER: Mojica FJ

PROVIDER: S-EPMC179144 | biostudies-other | 1997 Jun

REPOSITORIES: biostudies-other

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In vivo supercoiling of plasmid and chromosomal DNA in an Escherichia coli hns mutant.

Mojica F J FJ Higgins C F CF

Journal of bacteriology 19970601 11

We have used trimethylpsoralen to measure localized levels of unconstrained DNA supercoiling in vivo. The data provide direct evidence that plasmid and chromosomal DNA supercoiling is altered in vivo in an hns mutant. This increase in supercoiling is independent of transcription or changes in the activity of topoisomerase I. These data have implications for the mechanisms by which the chromatin-associated protein H-NS may influence chromosome organization and gene expression. ...[more]

PMID: 9171396

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