Project Director

Giles, David K.

Department Examiner

Spratt, Henry G.


Dept. of Biological and Environmental Sciences


University of Tennessee at Chattanooga

Place of Publication

Chattanooga (Tenn.)


Methicillin resistant Staphylococcus aureus (MRSA) is a potentially pathogenic bacterium that poses a serious risk in healthcare settings. MRSA can be characterized by a genetic element, known as the staphylococcal cassette chromosome, which harbors the gene responsible for methicillin resistance, mecA. MRSA can be classified into two categories: community acquired (CA) and hospital acquired (HA). S. aureus strains represent a major health concern due to their prevalence in healthcare facilities and their rapidly evolving antibiotic resistance. The current study investigated the association between MRSA isolates obtained from patients and from the intensive care units in a local hospital. Among the bacteria isolated from the neonatal and pediatric intensive care units were Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and members of the Micrococcus and Bacillus genera. MRSA isolates were confirmed by a combination of mannitol salt agar, CHROM agar, and antibiotic disc diffusion tests. Genomic DNA was extracted from the MRSA isolates by multiplex PCR to differentiate between CA and HA. We utilized multiple genomic markers to identify the mecA gene, differentiate the types of MRSA, and observe if specific toxins were present in twenty-five patient samples and eight environmental samples. In patient samples type II (HA), type III (HA), and type IVd (CA) were confirmed. In environmental samples type III (HA), type IVa (CA), and type V (CA) were confirmed. Both patient and environmental samples expressed the mecA gene indicative of MRSA. The only correlative genomic marker between patient and environmental samples was the type III and mecA gene; however, several isolates possessed mecA but did not match any of the types tested. Ongoing research involves the examination of over fifty more MRSA isolates, allowing further molecular characterization and determination of MRSA exchange in a healthcare setting.


I would like to acknowledge Dr. David K. Giles for his guidance and support in my research the past two years. He has continuously worked to help me understand concepts and methodologies, shed light onto new opportunities, and to challenge myself. This project could not have been done without him. I would also like to acknowledge Colin M. Smith for assisting with lab work. Special thanks to Dr. Margaret J Kovach for providing access to equipment for PCR and gel documentation. A big thank you is owed to the Collaborative Research Initiative for Sponsored Programs (CRISP) grant, the UTC Honors College, and Provost Student Research Award for supporting this project.


B. S.; An honors thesis submitted to the faculty of the University of Tennessee at Chattanooga in partial fulfillment of the requirements of the degree of Bachelor of Science.




Staphylococcus aureus infections -- Prevention


MRSA; Patient; Environmental; Isolate; Methicillin; Resistance; Staphylococcus aureus



Document Type



51 leaves







Date Available


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Biology Commons