Polymorphisms of agr locus correspond to distinct genetic patterns of virulence in Staphylococcus aureus clinical isolates from orthopedic implant infections

Lucio Montanaro, Pietro Speziale, Davide Campoccia, Valter Pirini, Stefano Ravaioli, Ilaria Cangini, Livia Visai, Carla Renata Arciola

Research output: Contribution to journalArticle

Abstract

Staphylococcus aureus is the leading etiologic agent of orthopedic implant infections. It is endowed with the accessory gene regulator (agr) locus that modulates expression of many virulence genes. Four allelic groups of agr have been recognized within this bacterial species. Here, 200 S. aureus isolates from orthopedic implant infections, typed at the start depending on their agr group, were screened for the presence of adhesin and leukotoxin genes. Interestingly, specific virulence gene patterns emerged in association with agr groups. The most frequently observed agr groups, agr I and agr II, were associated with the presence of sdrE, fib (agr II more than agr I), fnbB (agr I more than agr II), and lukE/lukD (agr II more than agr I). The third more frequent agr group, agr III, differed clearly from agr I and II, exhibiting high prevalence of bbp, generally not harbored by agr I and II, and copresence of bbp with cna, whereas high prevalence of the tandem sdrE/fib marked defi-nitely agr II (91% of agr II isolates), and, though less strictly, agr I, in which prevailed the peculiar fib/fnbB pattern. The only four isolates belonging to agr IV showed full copresence of bbp with fib. Results point out distinct patterns of virulence genes, which underlie distinct evolutive strategies associated to agr groups in S. aureus causing orthopedic implant infections.

Original languageEnglish
Pages (from-to)825-832
Number of pages8
JournalJournal of Biomedical Materials Research - Part A
Volume94
Issue number3
DOIs
Publication statusPublished - Sep 1 2010

    Fingerprint

Keywords

  • Adhesions
  • agr
  • Leukotoxins
  • Orthopedic implant infections
  • Polymorphism
  • Staphylococus aureus

ASJC Scopus subject areas

  • Biomedical Engineering
  • Biomaterials
  • Ceramics and Composites
  • Metals and Alloys

Cite this