Bacillus indicus sp. nov., an arsenic-resistant bacterium isolated from an aquifer in West Bengal, India

Strain Sd/3T (=MTCC 4374T=DSM 15820T), an arsenic-resistant bacterium, was isolated from a sand sample obtained from an arsenic-contaminated aquifer in Chakdah district in West Bengal, India (23 degrees 3' N 88 degrees 35' E). The bacterium was Gram-positive, rod-shaped, non-motile, endospore-forming and yellowish-orange pigmented. It possessed all the characteristics that conform to the genus Bacillus, such as it had A4beta murein type (L-orn-D-Asp) peptidoglycan variant, MK-7 as the major menaquinone and iso-C15 : 0 and anteiso-C15 : 0 as the major fatty acids. Based on its chemotaxonomic and phylogenetic characteristics, strain Sd/3T was identified as a species of the genus Bacillus. It exhibited maximum similarity (95%) at the 16S rRNA gene level with Bacillus cohnii; however, DNA-DNA similarity with B. cohnii was 60.7%. Strain Sd/3T also exhibited a number of phenotypic differences from B. cohnii (DSM 6307T). These data suggest that Sd/3T represents a novel species of the genus Bacillus. The name Bacillus indicus sp. nov. is proposed.