Investigation of mecA gene and in-vitro antimicrobial activityof some benzoyl thiourea derivatives in methicillin resistantStaphylococcus aureus isolates

Infections caused by multi-drug resistant bacteria cause important health problems today. This situation has led to an increase in the number of researches conducted to develop new antibiotics in recent years. The World Health Organization reports that the efficacy of antibiotics against multidrug-resistant infectious agents, especially methicillin-resistant Staphylococcus aureus (MRSA) strains, is gradually decreasing. In this thesis, it was aimed to investigate the prevalence of Staphylococcus aureus and Methicillin-resistant S.aureus (MRSA), multi-antibiotic resistance status of MRSA isolates and antibacterial activity of 3 different benzoylthiourea compounds (N-((2-chloropyridin-3-yl) carbamothioyl) thiophene-2-carboxamide (L-31), N-(morpholine-4-carbonothioyl) benzamide (EHL-90) ve N-(diphenylcarbamothioyl)benzamide (EHL93)) against MRSA isolates in different clinical samples. As a result of the analyzes, S. aureus was detected in 45 (45%) of a total of 100 (burn, wound, ear, abscess, nose) swab samples with morphological and biochemical tests. Methicillin resistance was demonstrated in 22 (48%) isolates with the antibiotic susceptibility test performed on S. aureus isolates using Methicillin and cefoxitin discs. Multidrug resistance was determined in all 22 MRSA isolates. The presence of mecA gene was determined by PCR in all MRSA isolates identified by conventional methods. Benzylthiourea compounds were applied and their effectiveness was proven at different rates. However, the most effective chemical is L93. With this thesis, it was concluded that the prevalence of MRSA and MDR-MRSA is at a significant level, and that the 3 benzoyl thiourea compounds used have the potential to be used as antibacterial agents at different concentrations.