Prevalence of PSM α and PSM β genes in biofilm-producing Staphylococcus aureus isolated from clinical samples

Authors
Ania Ahani Azari 1
Ali Asghar Ayatollahi 2
Abolfazl khandandel 3
1 Department of Microbiology, Gorgan Branch, Islamic Azad University, Gorgan, Iran
2 Sciences Research Center, Golestan University of Medical Sciences,Gorgan, Iran
3 Infectious Diseases Research Center, Golestan University of Medical Sciences, Gorgan, Iran
Abstract
Introduction

Staphylococcus aureus is one of the common causes of community- and hospital-acquired infections can be resistant to antibiotics and host immune systems through biofilm formation. One of the virulence factors of this organism is phenol-soluble modulus (PSMs) which are involved in biofilm formation. In this study, the prevalence of PSM α and PSM β genes among biofilm-producing S. aureus isolated from clinical samples was investigated.

Materials and Methods

The clinical samples were collected and examined for S. aureus using microbiological and conventional biochemical tests. Then, the presence of biofilm in the isolates was detected by a microtiter plate. Using PCR, the prevalence of PSM α and PSM β genes was determined.

Results

Out of the 60 isolates, the 47 isolates (78.3%) were positive for biofilm. Based on the PCR, the prevalence of PSM α and PSM β genes in the biofilm-producing isolates was 80% and 91.7%, respectively, while in the isolates without biofilm, the prevalence of these genes was 1.7% and 13.6%, respectively.

Conclusion

In this study, the PSM α and PSM β genes in the S. aureus isolates had a high prevalence. Therefore, it seemed to be a relationship between the frequency of these genes and the production of biofilms in this organism.
Keywords
Biofilm
Staphylococcus Aureus
Prevalence
PSM gene
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