The IncF Plasmid pRSB225 Isolated From a Municipal Wastewater Treatment Plant's On-Site Preflooder Combining Antibiotic Resistance and Putative Virulence Functions Is Highly Related to Virulence Plasmids Identified in Pathogenic E. Coli Isolates

Plasmid. 2013 Mar;69(2):127-37. doi: 10.1016/j.plasmid.2012.11.001. Epub 2012 Dec 2.

Abstract

The IncF antibiotic resistance and virulence plasmid pRSB225, isolated from an unknown bacterium released with the purified wastewater from a municipal sewage treatment plant into the environment has been analysed at the genomic level by pyrosequencing. The 164,550bp plasmid comprises 210 coding sequences (cds). It is composed of three replicons (RepFIA, RepFIB, and RepFII) and encodes further plasmid-specific functions for stable maintenance and inheritance and conjugative plasmid transfer. The plasmid is self-transmissible and shows a narrow host range limited to the family Enterobacteriaceae. The accessory modules of the plasmid mainly comprise genes conferring resistance to ampicillin (bla(TEM-1b)), chloramphenicol (catA1), erythromycin (mphA), kanamycin and neomycin (aphA1), streptomycin (strAB), sulphonamides (sul2), tetracycline (tetA(B)) and trimethoprim (dfrA14), as well as mercuric ions (mer genes). In addition, putative virulence-associated genes coding for iron uptake (iutA/iucABCD, sitABCD, and a putative high-affinity Fe²⁺ uptake system) and for a toxin/antitoxin system (vagCD) were identified on the plasmid. All antibiotic and heavy metal resistance genes are located either on class 1 (Tn10-remnant, Tn4352B) and class 2 transposons (Tn2-remnant, Tn21, Tn402-remnant) or a class 1 integron, whereas almost all putative virulence genes are associated with IS elements (IS1, IS26), indicating that transposition and/or recombination events were responsible for acquisition of the accessory pRSB225 modules. Particular modules of plasmid pRSB225 are related to corresponding segments of different virulence plasmids harboured by pathogenic Escherichia coli strains. Moreover, pRSB225 modules were also detected in entero-aggregative-haemorrhagic E. coli (EAHEC) draft genome sequences suggesting that IncF plasmids related to pRSB225 mediated gene transfer into pathogenic E. coli derivatives.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Anti-Infective Agents / pharmacology
  • Base Sequence
  • Chromosome Mapping
  • DNA Transposable Elements / genetics
  • Drug Resistance, Microbial / drug effects
  • Drug Resistance, Microbial / genetics*
  • Escherichia coli / drug effects
  • Escherichia coli / genetics*
  • Escherichia coli / isolation & purification
  • Escherichia coli / pathogenicity*
  • Genome, Bacterial / genetics
  • Genomic Islands / genetics
  • Iron / metabolism
  • Molecular Sequence Data
  • Plasmids / genetics*
  • Plasmids / isolation & purification*
  • Salmonella enterica / drug effects
  • Salmonella enterica / genetics
  • Sequence Analysis, DNA
  • Virulence / drug effects
  • Virulence / genetics
  • Waste Water / microbiology*
  • Water Purification*

Substances

  • Anti-Bacterial Agents
  • Anti-Infective Agents
  • DNA Transposable Elements
  • Waste Water
  • Iron

Associated data

  • GENBANK/JX127248