[CecropinA-magainin, a new hybrid antibacterial peptide against meticillin-resistant Staphylococcus aureus].

Objective: To study the mechanism of cecropinA-mangainin treatment on the meticillin-resistant Staphylococcus anreus biofilms.

Methods: The activity of the hybrid antibacterial peptide against Staphylococcus anreus was evaluated by the minimum inhibitory concentration (MIC) test and its effect on the bacteria membrane changes were observed through transmission electron microscope. The concentration of K+ of the tested bacterial liquid after interact with antibacterial peptide was detected with atomic absorption spectrometer. The changes of the treated bacteria biofilm was also evaluated by using flow cytometry.

Results: The results demonstrated that the MIC of the peptide against Staphylococcus aureus was 64 microg/mL. The ultrastructure changes of the meticillin-resistant Staphylococcus anreus membrane and the rising concentration of intracellular K+ were observed. And increased number of PI positive cells was also observed after hybrid antibacterial peptide treatmennt.

Conclusion: The hybrid antibacterial peptide could kill the meticillin-resistant Staphylococcus anreus by damage the treated bacteria membrane.