title: Comparative analyses of a putative Francisella conjugative element.
abstract: A large circular plasmid detected in Francisella novicida-like strain PA10-7858, designated pFNPA10, was sequenced completely and analyzed. This 41,013-bp plasmid showed no homology to any of the previously sequenced Francisella plasmids and was 8-10 times larger in size than them. A total of 57 ORFs were identified within pFNPA10 and at least 9 of them encoded putative proteins with homology to different conjugal transfer proteins. The presence of iteron-like direct repeats and an ORF encoding a putative replication protein within pFNPA10 suggested that it replicated by the theta mode. Phylogenetic analyses indicated that pFNPA10 had no near neighbors in the databases and that it may have originated within an environmental Francisella lineage. Based on its features, pFNPA10 appears to be a novel extra-chromosomal genetic element within the genus Francisella. The suitability of pFNPA10 as a vector for transformation of species of Francisella by conjugation remains to be explored.
authors.affiliation: a Institute of Bioinformatics and Applied Biotechnology, Bengaluru 560100, India.
authors.forename: Shivakumara
authors.initials: S
authors.lastname: Siddaramappa
authors.forename: Jean F
authors.initials: JF
authors.lastname: Challacombe
authors.forename: Jeannine M
authors.initials: JM
authors.lastname: Petersen
authors.forename: Segaran
authors.initials: S
authors.lastname: Pillai
authors.forename: Cheryl R
authors.initials: CR
authors.lastname: Kuske
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics; D001483:Base Sequence; D003227:Conjugation, Genetic / Q000235:genetics*; D005603:Francisella / Q000145:classification / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D010957:Plasmids / Q000737:chemistry / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins
keywords: Francisella; conjugal transfer proteins; plasmid; plasmide; protéines de transfert par conjugaison; réplication de type thêta; theta replication