[01] Kumurya A. S., Department of Medical Laboratory Science, Faculty of Allied Health Sciences, Bayero University, Kano, Nigeria. [02] Gwarzo M. Y., Department of Medical Laboratory Science, Faculty of Allied Health Sciences, Bayero University, Kano, Nigeria. [03] Uba A., Biological Science Programme, School of Science, Abubakar Tafawa Balewa University, Bauchi, Nigeria.

Background: Methicillin – resistant Staphylococcus aureus (MRSA) has also been noted as one of the main pathogen of public health importance.Detection of the mecA gene by polymerase chain reaction (PCR) is the gold standard for identifying methicillin-resistant Staphylococcus aureus (MRSA). Objectives: In order to accelerate the procedure of identification in clinical microbiology laboratories, it is very important to havea simple and rapid method for DNA extraction. In this work, a one step PCR assay for the detection of clinically relevant antibiotic resistance genes (mecA gene) harboredby some Staphylococcus aureus isolates and for the simultaneous identification of such isolates at the species level has been described. Methods: In this study, a rapid method for bacterial DNA extraction directly from a single colony that gave quality DNA for PCR in as littleas 0 minute was used. Polymerase chain reaction (PCR) was used to amplify both the S. aureus specific sequence gene and mecA gene of 100 isolates with the amplicon size of 107 and 532bp. Results: All the isolates (n=100) expressed S. aureus specific sequence gene in their PCR products. Only 5 isolates (5.0%) were confirmed as MRSA based on the detection of mecA gene.This protocol yielded good-quality target DNA for PCR amplification. Amplifications using that DNA gave rise to goodquantities of the expected PCR fragments. When PCR was performedusing DNA obtained by this method or previously reported methods, no differences were observed. Conclusion: Nowadays, with only a few antibiotics such as vancomycin constituting the last defense against MRSA, and due to the increasing incidence and spread of MRSA, it is absolutely necessary thatfast and sensitive laboratory methods are available for the immediate detection of multiple-antibiotic-resistant MRSA. This method reliably amplified DNA from Staphylococcus aureus colonies without a DNA extraction step. As our resultsshowed, the method herein described is highly sensitive, specific,fast, and feasible. Hence, considering that it represents a rapid, simple, and cost-effective method, it could be systematicallyapplied in clinical microbiology laboratories for the identification of MRSA, bringing insights into antibiotictherapy design and helping treatment to be initiated without delay.

Staphylococcus aureus, MRSA, MecA Gene, DNA, PCR

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