PBP2a detection was performed using monoclonal PBP2a antibody (1:20000) from the MRSA-screen kit (Denka Seiken). Acknowledgements We would like to thank Frances O’Brien (School of Biomedical Sciences, Curtin University of Technology) for determining the MLST types of strains ZH44 and ZH73. We would also like to thank Sibylle Burger for technical assistance and Dr. P. Hunziker, of the Functional Genomics Centre

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