Implication of peptidoglycan structure in methicillin resistance and vancomycin reduced susceptibility in Staphylococcus aureus

DI GREGORIO, S.; CUIROLO, A.; GARDELLA, N.; FERNANDEZ, S.; VERLAINE, O.; FAMIGLIETTI, A.; AMOROSO, A.; JORIS, B.; MOLLERACH, M.

Jornada; Jornadas científicas de la red de científicos argentinos en Bélgica (RCABL); 2013

Vancomycin is the treatment of choice for serious infectious caused by methicillin resistant Staphylococcus aureus (MRSA), but the mechanism of reduced susceptibility to this antibiotic (vancomycin intermediately susceptible S. aureus, VISA) and heterogeneous (hVISA) is poorly understood. We aim to perform the molecular characterization of two MRSA isolates recovered from a single patient suffering bone and joint infection: before and after vancomycin treatment (D1 and D2 respectively), and D2 derived mutants selected in increasing vancomycin concentrations, analyzing vancomycin and oxacillin susceptibility, cell wall thickness by transmission electron microscopy and peptidoglycan composition by RP-HPLC and mass spectroscometry of digested muropeptides