Anoxybacillus suryakundensis sp. nov, a moderately thermophilic, alkalitolerant bacterium isolated from hot spring at Jharkhand, India.

Abstract

Four closely related facultative anaerobe, moderately thermophilic, Gram positive rods (JS1(T), JS5, JS11, and JS15) were isolated from sediment samples from a hot spring at Suryakund, Jharkhand, India. Colonies were pale yellow, rough surface with uneven edges on TSA after 72 h incubation. Heterotrophic growth was observed at 40-60°C and pH 5.5-11.5; optimum growth occurred at 55°C and pH 7.5. 16S rRNA gene sequence analysis revealed the strains belong to genus Anoxybacillus. DNA-DNA homology values among strains were above 70% and showed distinct ERIC and REP PCR profile. On the basis of morphology and biochemical characteristics, strain JS1(T) was studied further. Strain JS1(T) showed 99.30% sequence similarity with A. flavithermus subsp. yunnanensis, 99.23% with A. mongoliensis, 99.16% with A. eryuanensis, 98.74% with A. flavithermus subsp. flavithermus, 98.54% with A. tengchongensis, 98.51% with A. pushchinoensis, 97.91% with A. thermarum, 97.82% with A. kaynarcensis, 97.77% with A. ayderensis and A. kamchatkensis, 97.63% with A. salavatliensis, 97.55% with A. kestanbolensis, 97.48% with A. contaminans, 97.27% with A. gonensis and 97.17% with A. voinovskiensis. In 16S rRNA secondary structure based phylogenetic comparison, strain JS1(T) was clustered with Anoxybacillus eryuanensis, A. mongoliensis, and A. flavithermus subsp. yunnanensis and showed 15 species specific base substitutions with maximum variability in helix 6. Moreover, DNA-DNA relatedness between JS1(T) and the closely related type strains were well below 70%. The DNA G+C content was 42.1 mol%. The major fatty acids were C(15:0 iso), C(16:0 iso) and C(17:0iso). The polar lipids were a phosphatidylgylycerol, a diphosphatidylglycerol, a phosphatidylethnolamine, a phosphatidylcholine, a phosphatidyl monomethylethanolamine and four unknown lipids. Based on polyphasic approach, strain JS1(T) represent a novel species of the genus Anoxybacillus for which Anoxybacillus suryakundensis sp. nov. is proposed. The type strain is JS1(T) (= DSM 27374(T) = LMG 27616(T) =JCM19211(T)).