Bacteriocin Produced by Halobacteria from Great Salt Lake Inhibits Gram Positive Organisms Taelor Kroeker, Jacqueline Young, and Dr. Ratnakar Deole Northeastern State University

Abstract

Antibiotic resistance is one of the major issues in nowadays community. Gram + bacterium like Methicillin-resistant Staphylococcus aureus(MRSA) is especially concerning due to fast mutation rates reducing the amount of potent antibiotics against it. Resistance of MRSA is attributed to misuse of antibiotics, and development of antibiotic resistance in nature, from MRSA’s frequent exposure to antimicrobial compounds within the same environment. Therefore, logical places to look for new potent antibiotics against Gram + organisms like MRSA are environments that MRSA does not inhabit, like hypersaline ecosystem, home of halophiles of all three domains of life. Great Salt Lake, Utah, harbors halophilic bacteria that produce antimicrobial compounds (bacteriocins) for nutrient competition elimination, which are active against MRSA. Antibiotic susceptibility and sensitivity assays were used to determine the domain of isolated microorganisms and whether they produce antimicrobial compounds. Protease test determined the nature of isolated antimicrobial compound. Tricine gel electrophoresis and contact bioassay were used to determine the size of the isolated antibiotic. Sample from Great Salt Lake showed the presence of bacteria producing bacteriocin which could be proteinaceous in nature. Bacteriocin was found capable of inhibiting the growth of Gram + bacteria grown in high salt. Its further characterization would help to better understand its mechanisms of action.