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Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR (RS-PCR)
08:51

Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR (RS-PCR)

Published on: November 4, 2016

Bacteriological characteristics of Staphylococcus aureus isolates from humans and bulk milk

E Hata1, K Katsuda, H Kobayashi

  • 1Hokkaido Research Station, National Institute of Animal Health, 4 Hitsujigaoka, Toyohira-Ku, Sapporo, Hokkaido 062-0045, Japan. ehata@affrc.go.jp

Journal of Dairy Science
|January 26, 2008
PubMed

Insights

This study found no direct link between human and animal Staphylococcus aureus strains using pulsed-field gel electrophoresis. Different bacterial characteristics suggest host-specific adaptation in these Staphylococcus aureus isolates.

Area of Science:

  • Microbiology
  • Epidemiology
  • Genetics

Background:

  • Staphylococcus aureus is a significant pathogen in both human and animal health.
  • Understanding the transmission dynamics and genetic relatedness of S. aureus isolates is crucial for effective control strategies.
  • Previous studies have explored the characteristics of S. aureus, but the epidemiological association between human and animal sources requires further clarification.

Purpose of the Study:

  • To investigate the epidemiological association between human and animal Staphylococcus aureus isolates.
  • To characterize the bacteriological profiles of S. aureus from different sources.
  • To explore potential host-specific adaptation mechanisms of S. aureus.

Main Methods:

  • Pulsed-field gel electrophoresis (PFGE) was employed to analyze the genetic relatedness of S. aureus isolates.
  • Isolates were characterized based on coagulase serotype, capsule serotype, exotoxin gene detection, and antimicrobial susceptibility testing.
  • Specific genes, including the penicillin-binding protein 2a gene and the LukM/LukF'-PV leukotoxin gene, were screened.

Main Results:

  • PFGE revealed distinct pulsotypes between bulk milk and human S. aureus isolates, indicating no direct epidemiological link.
  • Methicillin-resistant S. aureus (MRSA) from human secretions and S. aureus from bulk milk formed distinct clusters, while methicillin-susceptible S. aureus (MSSA) from humans showed diverse clustering.
  • Bulk milk isolates lacked the penicillin-binding protein 2a gene and predominantly exhibited susceptibility to common antibiotics, with a high prevalence of the LukM/LukF'-PV leukotoxin gene.

Conclusions:

  • The distinct genetic profiles and bacteriological characteristics suggest limited epidemiological association between human and bulk milk S. aureus isolates.
  • The presence of specific virulence factors, such as the LukM/LukF'-PV leukotoxin, and antimicrobial susceptibility patterns indicate host-specific adaptations in S. aureus.
  • Further research into these host-specific factors is warranted to understand the evolution and adaptation of S. aureus.

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