Mutation of an alternative sigma factor in the cyanobacterium Nostoc punctiforme results in increased infection of its symbiotic plant partner, Anthoceros punctatus.
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ABSTRACT:
SUBMITTER: Campbell EL
PROVIDER: S-EPMC107520 | biostudies-literature | 1998 Sep
REPOSITORIES: biostudies-literature
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Mutation of an alternative sigma factor in the cyanobacterium Nostoc punctiforme results in increased infection of its symbiotic plant partner, Anthoceros punctatus.
Campbell E L EL Brahamsha B B Meeks J C JC
Journal of bacteriology 19980901 18
An alternative group 2 sigma factor was identified in the nitrogen-fixing, symbiotically competent cyanobacterium Nostoc punctiforme and designated sigH. Transcription of sigH was specifically induced within 1.5 h following exposure of N. punctiforme to its symbiotic plant partner, Anthoceros punctatus. A mutation in sigH resulted in a sixfold-higher initial infection of A. punctatus tissue without a parallel increase in nitrogen-fixing activity. ...[more]
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