Determination of the ability to form biofilms and the presence of effectivegenes in adhesion (ica A, ica B, ica C and ica D) by Staphylococcus aureusisolated from clinical samples

Background & Objective: Staphylococcus aureus especially methicillin-resistant S. aureus (MRSA) strains are amajor cause of nosocomial and community acquired infections with high morbidity and mortality rates worldwide.The role of Biofilm is unclear in the spread of antibiotic resistance genes among gram-positive, such as S. aureuswhen compared with Gram-negative. The aims of this study were to determine Staphylococcal adhesion genes andmulti-drug resistant (MDR) isolates and detect the relative between their ability among clinical isolates of S.aureus.Methods: Sixty clinical specimens of Staphylococcus aureus were collected from clinical samples. Antibioticsusceptibility of S. aureus to ۹ different antibiotics was investigated using disk diffusion method based on CLSI table.DNA extraction of all isolates was performed by boiling method and PCR was performed. Biofilm formation abilitywas investigated using microtiter method. Then, by using the PCR method, the presence of the operons, icaA andicaB, icaC and icaD genes in all isolates was evaluated. Also, to find out the relationship between the binding genesin the specimens and the ability to produce biofilms and the presence of icaA and icaB target genes, was investigated.In the most isolated isolates of S. aureus, neither genes were found simultaneously. No significant correlation wasfound between the presence of fnbA binding gene and phenotypic antibiotic resistance tests (P value> ۰.۰۵).Conclusion: The target genes of icaA and icaB were found in most of the isolates of this study. The high presence oficaA and icaB simultaneously among a number of isolates should be considered as an important concern in theresistance phenomenon and biofilm formation .

کلیدواژه ها:

Staphylococcus aureus ، MRSA ، multi-drug resistance ، icaA and icaB