Complete sequence of pABTJ2, a plasmid from Acinetobacter baumannii MDR-TJ, carrying many phage-like elements

Genomics Proteomics Bioinformatics. 2014 Aug;12(4):172-7. doi: 10.1016/j.gpb.2014.05.001. Epub 2014 Jul 19.

Abstract

Acinetobacter baumannii is an important opportunistic pathogen in hospital, and the multidrug-resistant isolates of A. baumannii have been increasingly reported in recent years. A number of different mechanisms of resistance have been reported, some of which are associated with plasmid-mediated acquisition of genes. Therefore, studies on plasmids in A. baumannii have been a hot issue lately. We have performed complete genome sequencing of A. baumannii MDR-TJ, which is a multidrug-resistant isolate. Finalizing the remaining large scaffold of the previous assembly, we found a new plasmid pABTJ2, which carries many phage-like elements. The plasmid pABTJ2 is a circular double-stranded DNA molecule, which is 110,967bp in length. We annotated 125 CDSs from pABTJ2 using IMG ER and ZCURVE_V, accounting for 88.28% of the whole plasmid sequence. Many phage-like elements and a tRNA-coding gene were detected in pABTJ2, which is rarely reported among A. baumannii. The tRNA gene is specific for asparagine codon GTT, which may be a small chromosomal sequence picked up through incorrect excision during plasmid formation. The phage-like elements may have been acquired during the integration process, as the GC content of the region carrying phage-like elements was higher than that of the adjacent regions. The finding of phage-like elements and tRNA-coding gene in pABTJ2 may provide a novel insight into the study of A. baumannii pan-plasmidome.

Keywords: A. baumannii; Phage-like elements; Plasmid; tRNA gene.

Publication types

  • Letter
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acinetobacter Infections / microbiology
  • Acinetobacter baumannii / classification
  • Acinetobacter baumannii / genetics*
  • Acinetobacter baumannii / isolation & purification
  • Bacteriophages / genetics*
  • DNA, Bacterial / genetics*
  • Humans
  • Phylogeny
  • Plasmids / genetics*
  • Polymorphism, Single Nucleotide / genetics
  • RNA, Transfer / genetics

Substances

  • DNA, Bacterial
  • RNA, Transfer