Abstract

Staphylococcus epidermidis CNBL 7032 is a heteroresistant strain, with subpopulations resistant to vancomycin concentrations up to 32 mg l (-1), which was isolated from cured pork meat. The mechanisms of glycopeptide resistance in this strain were investigated in this study. S. epidermidis CNBL 7032 does not harbour enterococcal transmissible vancomycin-resistance genes. Transmission electron microscopy revealed that resistant subpopulations have a thicker cell wall, and that the increase in cell wall thickness is proportional to vancomycin concentration in the growth medium. Scanning electron microscopy showed that S. epidermidis CNBL 7032 forms a biofilm-like structure when grown in the presence of vancomycin. This food isolate harbours the gene atlE, coding for an autolysin with an adhesive function, which is involved in the first phase of biofilm formation. This study has demonstrated an interaction between atlE expression, biofilm formation and glycopeptide antibiotic resistance; transcription analysis demonstrated that the expression of atlE increased proportionally with the vancomycin concentration in the culture. Insertional inactivation of atlE confirmed the role of the AtlE autolysin in biofilm and vancomycin resistance.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.