Salmonella enterica is a member of the Enterobacteriaceae family of gram-negative, non-spore forming, rod bacteria that are found in soil, water, and animals. There are 6 subspecies and over 2,600 serotypes. Salmonella species can cause many different diseases with gastroenteritis being the most common as it is associated with over 70% of foodborne infections. S. enterica is associated with food poisoning and characterized by vomiting, abdominal pains, diarrhea and headaches. Antibiotic resistance in Salmonella enterica is becoming widespread as a result of mechanisms including horizontal gene transfer of antibiotic resistance genes and mutations that can confer resistance to antibiotics. In order to characterize antibiotic resistance acquisition in S. enterica we studied the genomes of 20 environmental strains isolated from farmland in southeastern Georgia that were potentially exposed to antibiotics used from nearby farms raising livestock. We used bioinformatic methods to identify and characterize antibiotic resistance genes and mutations in these isolates, and infered the source and significance of antibiotic resistance acquired by these isolates. We identify antibiotic resistance mechanisms that were conferred via horizontal gene transfer or mutations via this analysis. Future work incoporate laboratory methods to verify antibiotic resistance identified using bioinformatic approaches, and compare antibiotic resistance profiles to clinical strains of S. enterica.
