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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)
12:18

Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)

Published on: February 9, 2011

Two-year study evaluating the potential loss of methicillin resistance in a methicillin-resistant Staphylococcus

William Veguilla1, K Kealy Peak, Vicki A Luna

  • 1Center for Biological Defense, College of Public Health, University of South Florida, 3602 Spectrum Blvd., Tampa, FL 33612, USA. wveguill@health.usf.edu

Journal of Clinical Microbiology
|August 22, 2008
PubMed

Insights

Cryopreservation of methicillin-resistant Staphylococcus aureus (MRSA) is stable. Monitoring 360 MRSA strains and 14 strains in a Microbank system for two years showed no significant loss of methicillin resistance.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Infectious Diseases

Background:

  • The mecA gene confers methicillin resistance in Staphylococcus aureus.
  • Concerns exist regarding the stability of cryopreserved bacterial strains, potentially impacting antimicrobial resistance research.
  • Maintaining the genetic integrity of resistant strains is crucial for accurate diagnostics and surveillance.

Purpose of the Study:

  • To assess the stability of the mecA gene in cryopreserved methicillin-resistant Staphylococcus aureus (MRSA) strains.
  • To evaluate the efficacy of standard cryostocking and Microbank preservation systems for long-term MRSA storage.
  • To determine if cryopreservation methods lead to a loss of methicillin resistance in MRSA populations.

Main Methods:

  • Monitoring 360 cryopreserved MRSA strains for genetic stability over two years.
  • Storing 14 well-characterized MRSA strains in a Microbank system.
  • Subjecting Microbank-stored strains to multiple freeze-thaw cycles.
  • Quantifying MRSA populations and assessing methicillin resistance levels post-storage.

Main Results:

  • No significant decline in methicillin-resistant populations was observed in cryostocked MRSA strains over two years.
  • MRSA strains stored in the Microbank system maintained their methicillin resistance after multiple freeze-thaw events.
  • Both cryostocking and Microbank preservation proved effective in preserving MRSA stability.

Conclusions:

  • Standard cryopreservation and Microbank systems are reliable for maintaining the stability of methicillin resistance in Staphylococcus aureus.
  • Long-term cryostorage does not appear to compromise the mecA gene integrity in MRSA.
  • These findings support the continued use of cryopreserved MRSA for research and surveillance.

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