gene molecular study of biofilm of staphylococcus aureus isolated from fresh milk using multiplex polymerase chain reaction

Background: Staphylococcus aureus is one of the main causes of food poisoning in the world. This pathogen has the ability to create biofilms that can lead to food contamination. The presence of biofilm genes in bacteria is very important. The aim of this study was to identify sticky genes (eno, cna, ebp, bbp) that play an important role in virulence and pathogenicity of the bacteria and even prevent the penetration of antibiotics in pathogenicity time. Materials and Methods: A total of 100 samples of fresh milk were collected from live animals and 60 isolates were selected to identify sticky genes (eno, cna, ebp, bbp) in the production of biofilm of S. aureus using the multiplex polymerase chain reaction method. In addition, the frequency rates of S. aureus strains resistant and susceptible to antibiotics such as methicillin, vancomycin, and clindamycin were determined among the samples. Results: From a total of 60 isolates of fresh milk, 43.4% of the colonies had laminin-binding protein gene or eno gene. Also, 90% of the isolates were sensitive to vancomycin, 50% sensitive to clindamycin and 43.4% sensitive to methicillin. Distribution rates of other sticky genes including ebp, cna, bbp were 11.6%, 20% and 25%, respectively. Molecular study results showed that the highest and lowest percentages of genes were related to the eno and bbp genes, respectively. Conclusion: The present study shows that the maximum sensitivity of the samples (90%) was related to vancomycin and the least amount of sensitivity (43.3%) was related to methicillin.