title: Abundance and diversity of plasmid-associated genes among clinical isolates of Enterococcus faecalis.
abstract: Enterococcus faecalis, a normal compound of the human intestinal microbiome, plays an important role in hospital-acquired infections. Plasmids make a significant contribution to the acquisition of the novel traits such as antimicrobial resistance and virulence by this pathogen. The study investigated the plasmid content and the diversity of plasmid-associated genes in a group of 152 hospital isolates of E. faecalis. The majority of plasmids visualized by pulsed-field gel electrophoresis of S1 nuclease-digested DNA fell into the range of 50-100 kb. PCR-based screening allowed detection of genes of the rep1(pIP501), rep2(pRE25), rep4(pMBB1), rep6(pS86), rep7(pT181), rep8(pAM373), rep9(pAD1/pTEF2/pCF10), rep10(pIM13) and rep13(pC194) families in 29 different combinations. The par and ω-ε-ζ plasmid stabilization systems were ubiquitous (45 isolates, 29.6% and 88 isolates, 57.9%, respectively), while the axe-txe system was not found. The asa1 gene homologues encoding aggregation substance characteristic for the pAD1 and related group of pheromone-responsive plasmids were present in 106 isolates. A variety of sequence variants, including novel ones, of genes associated with pheromone-responsive plasmids, such as rep8(pAM373), rep9(pAD1/pTEF2/pCF10), par, and asa1 were observed. In conclusion, there is a big and only partially characterized pool of diverse plasmids in clinical E. faecalis.
authors.affiliation: National Medicines Institute, ul. Chełmska 30/34, 00-725 Warsaw, Poland. Electronic address: ewardal@cls.edu.pl.
authors.forename: Ewa
authors.initials: E
authors.lastname: Wardal
authors.forename: Iwona
authors.initials: I
authors.lastname: Gawryszewska
authors.forename: Waleria
authors.initials: W
authors.lastname: Hryniewicz
authors.forename: Ewa
authors.initials: E
authors.lastname: Sadowy
mesh_terms: D001426:Bacterial Proteins / Q000145:classification / Q000235:genetics*; D004251:DNA Transposable Elements; D003851:Deoxyribonucleases / Q000378:metabolism; D016521:Electrophoresis, Gel, Pulsed-Field; D013293:Enterococcus faecalis / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D014644:Genetic Variation; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology; D006801:Humans; D010675:Pheromones / Q000235:genetics; D010802:Phylogeny; D010957:Plasmids / Q000737:chemistry* / Q000145:classification; D017422:Sequence Analysis, DNA
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D010675:Pheromones; C065937:aggregation substance, Enterococcus faecalis; D003851:Deoxyribonucleases
keywords: HiRECC; asa; cyl; par; rep