Bacillus rigui sp. nov., isolated from wetland fresh water

Abstract

Two Gram-stain-positive strains, WPCB074(T) and WPCB165, were isolated from fresh water collected from the Woopo wetland (Republic of Korea). Both strains were strictly aerobic, motile, endospore-forming rods. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains WPCB074(T) and WPCB165 belonged to the genus Bacillus and that strain WPCB074(T) was most closely related to Bacillus solisalsi YC1(T) (98.4 % sequence similarity), B. barbaricus V2-BIII-A2(T) (97.7 %), B. macauensis ZFHKF-1(T) (96.9 %), B. arsenicus Con a/3(T) (96.4 %) and B. gelatini LMG 21880(T) (95.1 %). The 16S rRNA gene sequences of strains WPCB074(T) and WPCB165 differed at one position (99.9 % similarity), suggesting that these two strains constitute a single species. DNA-DNA relatedness between strain WPCB074(T) and the type strains of B. solisalsi, B. barbaricus, B. macauensis, B. arsenicus and B. gelatini were 26, 17, 20, 14 and 7 %, respectively. Strain WPCB074(T) was characterized by having cell-wall peptidoglycan based on meso-diaminopimelic acid, MK-7 as the predominant menaquinone and iso-C(15 : 0) and anteiso-C(15 : 0) as the major fatty acids. The DNA G+C content of strain WPCB074(T) was 41.9 mol%. On the basis of phenotypic properties, phylogeny and genomic distinctiveness, strain WPCB074(T) represents a novel species of the genus Bacillus for which the name Bacillus rigui sp. nov. is proposed. The type strain is WPCB074(T) (=KCTC 13278(T) =JCM 16348(T)).