title: Prevalence and mapping of a plasmid encoding a type IV secretion system in Acinetobacter baumannii.
abstract: We investigated the prevalence of a type IV secretion system (T4SS)-bearing plasmid among clinical isolates of carbapenem-resistant Acinetobacter baumannii (CRAB) using plasmid replicon typing. The complete sequence of a T4SS-bearing plasmid, pAB_CC, isolated from A. baumannii TYTH-1 was determined, and a comparative analysis of the T4SS gene modules was performed. Of the 129 isolates studied, GR6 (repAci6) was the most common (45 of 96 isolates) and was strongly linked with the T4SS. A comparative analysis of the T4SS locus in seven plasmid genomes, including pAB_CC, pACICU2, pABKp1, pABTJ1, p1BJAB0714, p2BJAB0868, and p2ABTCDC0715, indicated that fourteen genes on these plasmids were highly conserved compared to those of the F plasmid. Additionally, the chromosomes in the seven representative isolates may be evolutionarily distinct from their intrinsic T4SS-bearing plasmids, suggesting that the two T4SS lineages emerged long before the appearance of EC II. These two lineages are now widespread in A. baumannii strains.
authors: Department of Bioinformatics, Chung Hua University, Hsin-Chu City, Taiwan; Department of Computer Science and Information Engineering, Providence University, Taichung County, Taiwan.
authors: Chih-Chin
authors: CC
authors: Liu
authors: Department of Medicine, National Taiwan University Hospital Hsin-Chu Branch, Hsin-Chu City, Taiwan; School of Medicine, National Taiwan University, Taipei City, Taiwan.
authors: Han-Yueh
authors: HY
authors: Kuo
authors: Department of Computer Science and Information Engineering, Providence University, Taichung County, Taiwan; Department of Computer Science, National Tsing Hua University, Hsin-Chu City, Taiwan.
authors: Chuan Yi
authors: CY
authors: Tang
authors: Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien City, Taiwan.
authors: Kai-Chih
authors: KC
authors: Chang
authors: Department of Computer Science and Information Engineering, Providence University, Taichung County, Taiwan; Department of Medical Laboratory Science and Biotechnology, Yuanpei University, Hsin-Chu City, Taiwan. Electronic address: d918229@gmail.com.
authors: Ming-Li
authors: ML
authors: Liou
mesh_terms: D040981:Acinetobacter baumannii / Q000187:drug effects / Q000235:genetics*; D058947:Bacterial Secretion Systems / Q000235:genetics*; D001483:Base Sequence; D015780:Carbapenems / Q000494:pharmacology; D017124:Conserved Sequence; D019143:Evolution, Molecular; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D010802:Phylogeny; D010957:Plasmids / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D058947:Bacterial Secretion Systems; D015780:Carbapenems
keywords: Acinetobacter baumannii; Replicon typing; Type IV secretion system