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Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus
09:03

Multiplex PCR Assay for Typing of Staphylococcal Cassette Chromosome Mec Types I to V in Methicillin-resistant Staphylococcus aureus

Published on: September 5, 2013

Superantigenic toxin genes coexist with specific staphylococcal cassette chromosome mec genes in

Dong-Liang Hu1, Edward K Maina, Katsuhiko Omoe

  • 1Department of Microbiology and Immunology, Hirosaki University Graduate School of Medicine, Japan. hudl@cc.hirosaki-u.ac.jp

The Tohoku Journal of Experimental Medicine
|October 6, 2011
PubMed

Insights

Methicillin-resistant Staphylococcus aureus (MRSA) carrying specific toxin genes are linked to common SCCmec types I and II. This association may enhance MRSA

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Genetics

Background:

  • Methicillin-resistant Staphylococcus aureus (MRSA) is a significant global pathogen causing both hospital and community infections.
  • Superantigenic toxins produced by MRSA can lead to severe inflammatory responses and sepsis.
  • The spread and treatment difficulty of MRSA highlight the need to understand its virulence factors.

Purpose of the Study:

  • To investigate the prevalence of staphylococcal cassette chromosome mec (SCCmec) genes and superantigenic toxin genes in clinical MRSA isolates.
  • To determine the association between specific SCCmec types and the carriage of superantigenic toxin genes.

Main Methods:

  • Multiplex polymerase chain reactions were used to detect SCCmec and staphylococcal superantigenic toxin genes in 131 MRSA isolates.
  • MRSA isolates were classified based on their SCCmec gene types.

Main Results:

  • The majority of MRSA isolates were classified as SCCmec type II (74.8%) and type I (13.0%).
  • A high proportion of MRSA isolates (102/131) carried superantigenic toxin genes, including staphylococcal enterotoxin (se) and toxic shock syndrome toxin-1 (tst-1).
  • SCCmec types I and II MRSA isolates were more frequently associated with a specific profile of superantigenic toxin genes (sec, seg, sei, sell, selm, seln, selo, and tst-1).

Conclusions:

  • A significant link exists between SCCmec types I and II and the presence of specific superantigenic toxin genes in MRSA.
  • The co-occurrence of these toxin genes and SCCmec types may contribute to the enhanced pathogenicity and fitness of MRSA.
  • Understanding these genetic associations is crucial for developing targeted therapeutic strategies against MRSA infections.

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