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Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

Distinct bacteriophages encoding Panton-Valentine leukocidin (PVL) among international methicillin-resistant

E Boakes1, A M Kearns, M Ganner

  • 1Staphylococcus Reference Unit, Laboratory of Healthcare Associated Infections, Centre for Infections, Health Protection Agency, 61 Colindale Avenue, London NW9 5EQ, United Kingdom. eve.boakes@hpa.org.uk

Journal of Clinical Microbiology
|November 26, 2010
PubMed

Insights

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strains carry Panton-Valentine leukocidin (PVL) bacteriophages. This study maps PVL phage distribution, gene sequences, and chromosomal insertion sites in diverse MRSA strains, revealing lineage-specific patterns crucial for understanding microepidemiology and predicting emergence.

Area of Science:

  • Microbiology
  • Genetics
  • Epidemiology

Background:

  • Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) can harbor bacteriophages encoding Panton-Valentine leukocidin (PVL) as prophages.
  • Six distinct PVL phages are known, with variations in PVL genes (SNPs) previously reported.

Purpose of the Study:

  • To investigate the distribution of lysogenized PVL phages in PVL-MRSA strains.
  • To analyze PVL gene sequences and identify chromosomal phage insertion sites across diverse MRSA clones.

Main Methods:

  • Utilized PCR to identify six known PVL phages in 114 MRSA isolates from nine genetically diverse clones.
  • Analyzed chromosomal insertion sites for PVL phages in 92 isolates, correlating them with specific clonal lineages (CCs and STs).

Main Results:

  • ΦSa2USA was the most prevalent PVL phage, found in multiple lineages including CC1, CC5, CC8, and ST93.
  • PVL phages exhibited lineage-specific chromosomal insertion sites: one locus for CC22, -30, -80, and a different locus for CC1, -5, -8, -59, -88, and ST93.
  • Specific attachment motifs were identified at insertion sites, with minor sequence variations observed.

Conclusions:

  • Established lineage-specific relationships between PVL phages, toxin genes, and chromosomal integration sites in MRSA.
  • Findings offer critical insights into PVL-MRSA microepidemiology, aiding outbreak investigations and strain emergence prediction.

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