Bacillus polygoni sp nov., a moderately halophilic, non-motile obligate alkaliphile isolated from indigo balls

A moderately halophilic, obligate alkaliphile (growth range pH 8 - 12), designated strain YN-1(T), was isolated from indigo balls obtained from Ibaraki, Japan. The cells of the isolate stained Gram-positive, and were aerobic, non-motile, sporulating rods which grew optimally at pH 9. The strain grew in 3 - 14 % NaCl with optimum growth in 5 % NaCl. It hydrolysed casein and Tweens 20, 40 and 60, but not gelatin, starch, DNA or pullulan, Its major isoprenoid quinone was MK-7 and its cellular fatty acid profile mainly consisted of anteiso-C-15:0, anteiso-C-17:0 and anteiso-C-17:1. 16S rRNA phylogeny suggested that strain YN-1(T) was a member of group 7 (alkaliphiles) of the genus Bacillus, with the closest relative being Bacillus clarkii DSM 8720(T) (similarity 99.5%). However, DNA - DNA hybridization showed a low DNA - DNA relatedness (7%) of strain YN- 1(T) with B. clarkii DSM 8720(T). Owing to the significant differences in phenotypic and chemotaxonomic characteristics, and phylogenetic and DNA - DNA relatedness data, the isolate merits classification as a new species, for which the name Bacillus polygoni is proposed. The type strain of this species is YN-1(T) (=JCM 14604(T)=NCIMB 14282(T)).