Biofilm formation in Methicillin Resistant Staphylococcus aureus

Methicillin Resistant Staphylococcus aureus (MRSA) is one of the important antibiotic resistance pathogen. Chronic hospital acquired infections by S. aureus have become a major problem in recent years. One of the main mechanisms for chronic hospital acquired infections is defined by biofilm formation. Therefore, the current research aimed to identify the prevalence of biofilm formation among MRSA clinical isolates in Ilam hospitals and to determine the gene responsible for biofilm formation. For this reason, 26 MRSA clinical isolates were identified and subjected to biofilm by micro-plate assay and PCR for identification of icaa and icaD. The results demonstrated that 69.2% (n = 18) of MRSA clinical isolates possess icaD and were interestingly were negative for icaa; while biofilm formation were negative in three isolates that were positive for icaD. The current study strongly recommended icaD as a main factor to produce the biofilm formation in MRSA clinical isolates and suggested this gene as a target for antibiofilm therapy. The reason for negatively in 2 isolates could be explained in the abstract by low accuracy of micro-late assay. Another reason that could be concluded was silencing of icaD in these three isolates.