Methicillin Resistance in Staphylococcus aureus: A Review of the mecA Gene and Its Role in Antibiotic Resistance

Faiqa Tabassum; Anam Munir; Faiqa Shakeel; Tania Zia; Muhammad Umar Zafar Khan; Zohaib Tahir

doi:10.70749/ijbr.v3i9.2302

Authors

Faiqa Tabassum Institute of Microbiology University of Agriculture, Faisalabad, Punjab, Pakistan.
Anam Munir Institute of Microbiology University of Agriculture, Faisalabad, Punjab, Pakistan.
Faiqa Shakeel Faculty of Engineering and Science (FES), University of Greenwich, England.
Tania Zia Department of Microbiology, University of Central Punjab, Lahore, Punjab, Pakistan.
Muhammad Umar Zafar Khan Institute of Microbiology University of Agriculture, Faisalabad, Punjab, Pakistan.
Zohaib Tahir Faculty of Pharmacy, Gomal University, Dera Ismail Khan, KP, Pakistan.

DOI:

https://doi.org/10.70749/ijbr.v3i9.2302

Keywords:

Staphylococcus aureus, MRSA, mecA gene, PBP2a, β-lactam Resistance, Antimicrobial Resistance, SCCmec, Molecular Diagnostics.

Abstract

Staphylococcus aureus is a common pathogen that can cause a wide range of infections, including endocarditis, severe bacteremia, and infections of the skin and soft tissues. Because of its resistance to β-lactam antibiotics, methicillin-resistant S. aureus (MRSA), which is caused by the mecA gene encoding penicillin-binding protein 2a (PBP2a), is a serious problem. This review describes the molecular mechanisms, regulatory pathways involving mecR1 and mecI, and the genetic context of mecA within the Staphylococcal Cassette Chromosome mec (SCCmec). Along with diagnostic techniques like PCR, CRISPR-based detection, and next-generation sequencing, we investigate the epidemiology of hospital-acquired (HA-MRSA), community-acquired (CA-MRSA), and livestock-associated (LA-MRSA) strains. Vancomycin resistance is one of the therapeutic limitations that are addressed; new strategies such as phage therapy, combination therapies, and anti-PBP2a inhibitors show promise. Emerging resistance mechanisms, such as mecC and biofilm formation, highlight the need for surveillance. In order to lessen MRSA's worldwide impact, future strategies will prioritize stewardship, new antibiotics, and quick diagnostics.

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