The Molecular Detection of mecA Genes of Staphylococcus Aureus

Abstract

Antibiotic resistance is common among pathogenic bacteria associated with community acquired and nosocomial infections. Methicillin-resistant Staphylococcus aureus (MRSA) infections have become a global health problem particularly in hospital setup causing simple skin infections to life threatening infections. The present study aimed to investigate the presence of mecA genes in MRSA from pigs, using Polymerase Chain Reaction. One hundred S. aureus isolates of blood samples from Pigs in Bariga, Lagos State were collected from Molecular Biology and Biotechnology Unit, Nigeria Institute of Medical Research. Methicillin resistance was determined by Kirby-Bauer’s disc diffusion method. The PCR was used for mecA gene detection from MRSA strains. Twenty-five pure Staphylococcus aureus isolates were identified based on cultural characteristics, biochemical reactions and positive slide coagulase test. Out of these, 11 (44%) strains were MRSA by phenotypic method. Amplification of mecA gene for all the 11 MRSA isolates was negative when visualized on 2% agarose gel electrophoresis. Eleven strains of MRSA were found among Staphylococcus aureus isolates of blood samples from Pigs. The MRSA phenotype observed in the isolates was not the classical mecA mediated resistance. Hence, it is highly recommended to consider alternative mechanisms for β-lactams resistance that may compete with mecA gene in the emergence of MRSA phenomenon in Nigeria.