Isolation and characterization of Thermoanaerobacter mathranii SC-2 from oil-field water

Abstract:

[Objective] We studied physiological, biochemical properties and metabolites of Thermoanaerobacter mathranii SC-2 from oil-field water in Shengli oilfield. [Methods] Strain SC-2 was isolated by Hungate anaerobic technique. Through physiological, biochemical and phylogenetic analysis, the strain was identified. Metabolites were analyzed by gas chromatogram. [Results] The cells were Gram-negative, rod-shaped, spore-forming. Growth was observed in the temperature range from 40 to 75℃(optimum 70℃) and pH range from 5.5 to 9.5 (optimum 6.5). The isolate grew in the presence of 0%~5% NaCl with an optimum without NaCl at pH 7.0 and 65℃. Strain SC-2 used many carbohydrates as carbon sources, including glucose and xylose. Metabolites of glucose were ethanol, acetate, propionate, lactate, CO2 and H2. Based on 16S rDNA studies, strain SC-2 was most close to T. mathranii subsp. mathranii11246T with 99.85% similarity. More ethanol and acetate were produced at initial pH 8.0 than yields at other pH. Yeast extract could significantly increase ethanol and acetate yields. In addition, ethanol (4%) added in the medium obviously inhibited its growth. [Conclusion] Strain SC-2 was extremely thermophilic, halotolerant anaerobe.