title: Mutation of an alternative sigma factor in the cyanobacterium Nostoc punctiforme results in increased infection of its symbiotic plant partner, Anthoceros punctatus.
abstract: 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.
authors.affiliation: Section of Microbiology, Division of Biological Sciences, University of California, Davis, California 95616, USA.
authors.forename: E L
authors.initials: EL
authors.lastname: Campbell
authors.forename: B
authors.initials: B
authors.lastname: Brahamsha
authors.forename: J C
authors.initials: JC
authors.lastname: Meeks
mesh_terms: D000595:Amino Acid Sequence; D000458:Cyanobacteria / Q000502:physiology*; D008969:Molecular Sequence Data; D009154:Mutation; D016366:Open Reading Frames; D010641:Phenotype; D010944:Plants / Q000382:microbiology*; D012808:Sigma Factor / Q000737:chemistry / Q000502:physiology*; D013559:Symbiosis; D014158:Transcription, Genetic
chemical_list: D012808:Sigma Factor