Biofilm formation and surface protein encoding genes in methicillin-resistant Staphylococcus aureus isolated from patients in Srinagarind Hospital, Khon Kaen province

Abstract

Methicillin-resistant Staphylococcus aureus (MRSA), the principal Gram-positive bacteria pathogen, plays an important role as a common causative agent of various infectious diseases both in community and hospital.  Pathogenesis of S. aureus has been associated with multiple factors such as toxin production. Biofilm formation and surface proteins have been supposed to be initial properties of infection process. Thus, the objectives of this study were to determine whether biofilm formation of MRSA strains was associated with the distribution of biofilm-producing gene, icaA and surface protein genes, including clfA, clfB, fnbA, ebpS, sasG, sdrC, sdrD, and sdrE among those MRSA isolates. A total of 126 MRSA isolates from unrepeated patients of Srinagarind Hospital, which were typed by PCR-based typing techniques including SCCmec typing and variable number  of  tandem repeat typings were enrolled in this study. Biofilm detection was performed by microtiter plate (MTP) technique and the surface protein genes were detected by PCR. Only weak biofilm production was observed among 56 MRSA isolates (44.4%).  The surface protein encoding genes were detected in 79 % to 100% of the MRSA isolates, only ebpS gene was found in 6.3%. In addition, all isolates carried icaA gene. Moreover, there was no association of biofilm formation and MRSA genotypes.