Investigation of the Presence of mecA and mecC Genes and Antibiotic Resistance Profiles in Methicillin-Resistant Staphylococcus aureus Strains Isolated from Clinical Samples

Abstract

Objective: Methicillin-resistant Staphylococcus aureus (MRSA) is widely regarded as one of the most frequent bacteria, causing a wide range of infections in humans and animals. MRSA is associated with significant morbidity and mortality in many parts of the world. The aim of this study was to determine the molecular identification, antibiotic resistance profiles, and presence of mecA and mecC genes of MRSA strains isolated from clinical specimens at Siirt Training and Research Hospital. Methods: In our study, we isolated 20 coagulase positive S. aureus strains from patients admitted to our hospital between July 2020-July 2021. Antibiotic susceptibility tests were carried out on the bacteria that were isolated and identified by culturing various clinical samples. The mecA and mecC genes were then examined by polymerase chain reaction (PCR) using the universal primers mecA-F-mecA-R and mecC-F-mecC-R following MRSA had been identified in the cultures from the clinical samples. To identify the isolated S. aureus strains by 16S ribosomal ribonucleic acid (rRNA) gene analysis, polymerase chain reaction (PCR) amplification was conducted using universal primers 68f and 518r. Results: We isolated and identified 20 coagulase positive S. aureus strains from patients admitted to our hospital. According to the 16S rRNA gene sequences, the strains isolated in this this study, exhibited high similarity (99%-100%) to the 16S rRNA genes of S. aureus strains listed in GenBank (https ://ww w.ncb i.nlm .nih. gov/g enban k/). While the mecA gene was found in 18 of 20 strains, none of the strains had the mecC gene. A high percentage of MRSA was found to be penicillin resistant (75%). In conclusion, 20 MRSA strains were isolated from various clinical specimens. Eighteen of these strains were also identified molecularly by 16S rRNA sequence analysis. Conclusion: The results of this study confirmed the significance of the 16S rRNA, mecA, and mecC genes in MRSA identification and highlighted the increasing frequency of MRSA in Türkiye