title: Characterization of a plasmid isolated from Branhamella catarrhalis and detection of plasmid sequences within the genome of a B. catarrhalis strain.
abstract: We isolated a 12.2-kb plasmid from two clinical strains of Branhamella catarrhalis and evaluated its distribution among other B. catarrhalis strains by colony hybridization experiments using the whole plasmid as a probe. Homology was detected with the two plasmid-bearing strains and also with a third B. catarrhalis strain named E7, which is plasmidless. Southern transfer analysis of total digested E7 DNA using the purified plasmid as a probe revealed a single band of hybridization, different from those observed in plasmid-bearing strains, for each restriction enzyme used. The region of the plasmid hybridizing with DNA of strain E7 was located within a 4.5-kb SstI-EcoRV fragment. No homology was noted between our B. catarrhalis plasmid and about 20 other strains of different genera tested by colony hybridization.
authors.affiliation: Département de Biochimie, Faculté des Sciences et génie, Université Laval, Quebec, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Beaulieu
authors.forename: M
authors.initials: M
authors.lastname: Ouellette
authors.forename: M G
authors.initials: MG
authors.lastname: Bergeron
authors.forename: P H
authors.initials: PH
authors.lastname: Roy
mesh_terms: D015139:Blotting, Southern; D005798:Genes, Bacterial; D001936:Moraxella catarrhalis / Q000235:genetics*; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid