Genotype Diversity and Evaluation of Biofilm Formation in sasX Positive Methicillin-Resistant Staphylococcus aureus

Objectives: Staphylococcus aureus surface protein X (sasX) is a newly described protein that has different roles in virulence, such as biofilm formatin, as a bacterial approach for pathogenesis. SasX gene was initially found in eastern Asian countries, yet, studiese have shown spreading of this gene to other strains. Because there is no report on this gene in Iran, the current study aimed at determining the prevalence, genotype diversity, and evaluation of biofilm formation in sasX positive methicillin-resistant Staphylococcus aureus (MRSA). Methods: This experimental study was conducted on strains isolated from inpatients during ۲۰۱۴ to ۲۰۱۵. Cultivation, identification, and confirmation of MRSA isolates were performed. The evaluation of biofilm production, sasX gene detection, and Random amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR) were done. Data collection and comparison were performed by SPSS and gelcompare softwares. Results: Overall, ۱۴۰ isolates (۷۷.۸%) formed a biofilm and ۲۳ (۱۲.۶%) isolates were sasX positive. Amongst ۲۳ sasX+ strains, ۲۱ (۹۱.۳%) isolates created a biofilm. The RAPD-PCR analysis of ۲۳ sasX positive isolates showed ۱۹ RAPD types with ۴ common types (CT) and ۱۵ single types (ST). Conclusions: Frequency of sasX gene was somewhat similar to another study in eastern countries and the ability of biofilm formation in sasX+ strains compared to all of MRSA isolates were not significant (P value > ۰.۰۵) and a correlation was not found between RAPD type and biofilm grade.