title: Molecular characterization of a cryptic plasmid from the psychrotrophic antarctic bacterium Pseudoalteromonas sp. 643A.
abstract: We report the identification and nucleotide sequence analysis of pKW1, a plasmid of the psychrotrophic bacterium Pseudoalteromonas sp. 643A isolated from the stomach of Antarctic krill Euphasia superba. pKW1 consists of 4583 bp, has a G+C content of 43% and seven putative open reading frames (ORFs). The deduced amino acid sequence from ORF-1 shared significant similarity with the plasmid replicase protein of Psychrobacter cryohalolentis, strain K5. The DNA region immediately downstream of the ORF-1 showed some homology with the Rep-binding sequence of the theta-replicating ColE2-type plasmids. The ORF-3 amino acid sequence revealed amino acid sequence homology with the mobilization protein of Psychrobacter sp. PRwf-1 and Moraxella catarrhalis, with identities of 28% and 25%, respectively. The ORF-4 showed 46% amino acid sequence homology with the putative relaxase/mobilization nuclease MobA of Hafnia alvei and 44% homology with the putative mobilization protein A of Pasterulla multocida. The copy number of pKW1 in Pseudoalteromonas sp. 643A was estimated of 15 copies per chromosome.
authors.affiliation: Department of Microbiology, Chemical Faculty, Gdańsk University of Technology, Narutowicza 11/12, 80-952 Gdańsk, Poland.
authors.forename: Hubert
authors.initials: H
authors.lastname: Cieśliński
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Werbowy
authors.forename: Józef
authors.initials: J
authors.lastname: Kur
authors.forename: Marianna
authors.initials: M
authors.lastname: Turkiewicz
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000864:Antarctic Regions; D001483:Base Sequence; D033201:Euphausiacea / Q000382:microbiology*; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics*; D010957:Plasmids / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification; D031161:Pseudoalteromonas / Q000235:genetics* / Q000302:isolation & purification; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA