Isolation of Halophilic Bacteria from Inland Petroleum- Producing Wells

The goals of this study were to isolate microorganisms from oil well-produced water, identify the microorganisms, and test the microorganisms’ salt tolerance. Saltwater collected from two well locations producing from different zones in Jones County, Texas, was spread onto Mannitol Salt Agar (MSA). Isolates showed a 16S rDNA gene sequence identity of 99% with Idiomarina baltica and Marinobacter persicus. Salt tolerance assays indicated an optimal growth concentration of 10-12.5% NaCl for the Idiomarina isolate and a decrease in growth beyond 5% NaCl for the Marinobacter isolate. In conclusion, organisms that are phylogenetically similar to marine microorganisms are present in oil well environments, and have variable salt tolerances, which may prove useful in microbialmediated hydrocarbon bioremediation of high salinity environments.