Evaluation of Gene Expression of norA and norB Gene in Ciproflaxin and Levofloxacin Resistant Staphylococcus aureus

The presence of efflux pumps genes in Staphylococcus aureus, such as norA and norB, is critical for ciprofloxacin and levofloxacin resistance. This study examined the efflux pump gene expression and activity in ciprofloxacin and levofloxacin-resistant S. aureus strains. Twenty clinical samples of wounds and burns were collected. S. aureus strains were tested using specific culture media. Antibiotic susceptibility testing was done using the disc diffusion method. After determining the disc diffusion method of ciprofloxacin and levofloxacin, Methicillin-resistant Staphylococcus aureus (MRSA) isolates were found in ten of the twenty clinical samples. The susceptibility of S. aureus in the study revealed ۴۰% ciprofloxacin resistance and ۲۰% levofloxacin resistance. The gene expression of norA and norB efflux pump genes was assessed using Real-Time PCR. The nor A gene was detected in all ciprofloxacin-resistant pathogens, and norA gene expression increased in samples treated with ciprofloxacin compared to samples not treated with ciprofloxacin results of a real-time PCR test. The norB gene was detected in resistant strains, and its expression increased, as was the case with the norA gene. The fold of gene expression of norB gene for the ten isolates ranged from (۱۲.۰۸۲ to ۴۲.۸۱ fold) and also this result was higher than the fold of norA gene (۰.۰۰۳۶-۳۴.۰۵ fold). The research study discovered that efflux pump genes play a crucial role in ciprofloxacin and levofloxacin resistance. Also, when employed as a housekeeping gene in gene expression, the ۱۶S rRNA gene produced excellent results.

Keywords:

Gene expression , norA and norB , Staphylococcus aureus