Study of Prevalence of Toxic Shock Syndrome Toxin (TSST-1) and Methicilin Resistance (MecA) Genes of Staphylococcus aureus Isolates from Local Cheese in Northwest of Iran

Staphylococcal food poisoning is one of the most common food borne diseases. Widespread incidence of antibiotic resistances of Staphylococcus aureus have been reported in the world. The bacterium causes this poising by producing different toxins. The aim of this study was to determine the presence of toxic shock syndrome toxin (TSST-1) and methicillin resistance (mecA) producing genes in isolated S. aureus from local cheese in northwest of Iran. A total of 22 S. aureus samples, already identified by biochemical tests for diagnosis of S. aureus, were isolated from local cheese, and identified as S. aureus with proliferation of thermonuclease species-specific gene (nuc) by PCR method. To determine the frequency of TSST-1 and mecA, genes were tested by PCR method. Of 22 S. aureus isolates, one case (4.54%) contained mecA gene and two cases (9.09%) possessed TSST-1 gene. None of the tested isolates harbored the intended genes simultaneously. The presence of S. aureus isolates in local cheese, which harbor toxic shock syndrome toxin (TSST-1) and methicillin resistance (mecA) genes, show that these isolates have high potential in producing toxic shock syndrome toxin and methicillin resistance; therefore, the use of procedures to reduce the bacterial contamination during the processing of dairy product is required.