Ahmed, S., Tolba, S., Al Zawahry, Y. (2019). Evaluation of the Role Of bla Genes in Beta Lactam and Methicillin Resistant Staphylococcus aureus . Egyptian Journal of Botany, 59(1), 29-38. doi: 10.21608/ejbo.2018.4221.1187
Sarah H. Ahmed; Sahar T.M. Tolba; Yehia A. Al Zawahry. "Evaluation of the Role Of bla Genes in Beta Lactam and Methicillin Resistant Staphylococcus aureus ". Egyptian Journal of Botany, 59, 1, 2019, 29-38. doi: 10.21608/ejbo.2018.4221.1187
Ahmed, S., Tolba, S., Al Zawahry, Y. (2019). 'Evaluation of the Role Of bla Genes in Beta Lactam and Methicillin Resistant Staphylococcus aureus ', Egyptian Journal of Botany, 59(1), pp. 29-38. doi: 10.21608/ejbo.2018.4221.1187
Ahmed, S., Tolba, S., Al Zawahry, Y. Evaluation of the Role Of bla Genes in Beta Lactam and Methicillin Resistant Staphylococcus aureus . Egyptian Journal of Botany, 2019; 59(1): 29-38. doi: 10.21608/ejbo.2018.4221.1187
Evaluation of the Role Of bla Genes in Beta Lactam and Methicillin Resistant Staphylococcus aureus
1Department of Microbiology, Faculty of science -Ain-Shams University ,Cairo, Egypt
2Department of Botany, Zagazig University, Zagazig, Egypt
Abstract
One hundred and nineteen clinical samples were isolated from patients admitted in different hospitals in El-Sharkia Governorate. Sixty six isolates were confirmed to be S. aureus. Susceptibility to different antimicrobial agents and Minimum inhibitory concentration tests showed that all the isolates were resistant to 𝛽-lactam antibiotics, 77.2% (n= 51) isolates were methicillin resistant S. aureus MRSA, while almost all the isolates were sensitive to vancomycin and tigecycline. Polymerase chain reaction (PCR) of mecA, encoding methicillin resistance, and blaZ, β-lactamase biosynthetic gene, revealed the coexistence of both genes in 56.8% (n= 29/51) of the isolates. Meanwhile, 11.7% (n= 6/51) of MRSA isolates phenotypically resistant to oxacillin were found to be mecA-. This data support the fact that the expression of bla genes enhanced the phenotypic expression of oxacillin resistance as a result of β-lactamase hyperproduction. On the other hand, 33% of MRSA (n=17/51) were blaZ– suggesting a mutation event in blaZ or the existence of an alternative mechanisms for 𝛽-lactam resistance that may compete with mecA gene.