Bacillus patagoniensis sp nov., a novel alkalitolerant bacterium from the rhizosphere of Atriplex lampa in Patagonia, Argentina

A Gram-positive, rod-shaped, spore-forming bacterium (PAT 05(T)) was isolated from the rhizosphere of the perennial shrub Atriplex lampa in north-eastern Patagonia, Argentina. Its overall biochemical and physiological characteristics indicated that this strain should be placed in the alkaliphilic Bacillus group. Strain PAT 05(T) grew at pH 7-10 (optimum pH 8), but not at pH 6. Its DNA G+C content was 39(.)7 mol%. Sequence analysis of the 16S rRNA gene of PAT 05T revealed the closest match (99(.)6% similarity) with Bacillus sp. DSM 8714. The highest level of DNA-DNA relatedness (88(.)6%) was also found with this strain. On the oasis of 16S rRNA gene sequence similarity and phylogenetic analysis, G+C content and DNA-DNA hybridization data, strain PAT 05T is related at the species level to Bacillus sp. DSM 8714, a member of a group referred as phenon 4a by Nielsen et al. [Nielsen, P., Fritze, D. & Priest, F. G. (11995). Microbiology 141, 1745-1761], which still lacks taxonomic standing. These results support the proposal of strain PAT05(T) (= DSM 16117(T) = ATCC BAA-965(T)) as the type strain of Bacillus patagoniensis sp. nov.