A Bioinformatic Analysis of mecA Prevalence in Bacterial Species BY ISHAAN GOSWAMI (BAYVIEW GLEN INDEPENDENT SCHOOL) Cover Image: View of double stranded DNA Image Source: Pixabay
Abstract: Antibiotic resistance is a serious issue in healthcare. mecA is the gene in MRSA and many other bacterial species responsible for the development of resistance to commonly used β-lactam antibiotics. MRSA and other β-lactam resistant bacteria pose risks to health by increasing healthcare related mortality and morbidity rates. This paper aims to display the promising usage of bioinformatic tools in tackling antibiotic resistance by investigating the prevalence of mecA across bacterial species. It is imperative that further research be done to investigate the prevalence of other antibiotic resistant genes using similar bioinformatic approaches. Introduction Antibiotic resistance is a problem of great concern for the medical community. “Superbugs” are pathogens that undergo mutations which causes resistance to treatments, and can cause increasingly harmful infections. One such superbug is Methicillin-resistant Staphylococcus aureus (MRSA). Staphylococcus aureus is a gram-positive, coccal bacteria which causes staph infections and has the potential to cause serious complications, such as pulmonary, coronary, and urinary tract infections (Taylor & Unakal, 2018). Due to mutations, a strain of S. aureus has
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developed into MRSA and has become resistant to commonly used β-lactam antibiotics, which include penicillin and its derivatives such as methicillin (Green et al., 2012). mecA is a gene in MRSA conferring resistance to β-lactam antibiotics. (Ubukata et al., 1989). In susceptible strains of S. aureus, β-lactam antibiotics specifically inhibit a transpeptidase that catalyzes cell-wall crosslinking between polysaccharide chains and peptides, which creates a strong polymer called peptidoglycan that maintains the rigidity and shape of bacterial cell walls. However, in mutated forms of S. aureus that contain mecA, the gene encodes for a protein called PBP2A (penicillin-binding protein 2A), which has a low affinity for β-lactam antibiotics. This means that it does not bind to β-lactam antibiotics. This means that cell wall synthesis is not inhibited, and bacterial reproduction is unhampered (Fishovitz et al., 2014). MRSA is not benign and has been observed in clinical settings to be hazardous to health. Typically, MRSA infections occur in hospitals, nursing homes, dialysis centers, and other primary care locations. These cases of MRSA are called healthcare associated MRSA, or DARTMOUTH UNDERGRADUATE JOURNAL OF SCIENCE
