Neobacillus endophyticus Sp. Nov., an endophytic bacterium isolated from selaginella involvens roots

A Gram-stain-positive, facultatively anaerobic, rod-shaped, endospore-forming, oxidase-positive, and catalase-negative strain designated as BRMEA1^T was isolated from the surface-sterilized Selaginella involvens roots. Growth of strain BRMEA1^T was found to occur at pH 6.0–8.0 (optimum, pH 7.0), 15–50 °C (optimum, 25–30 °C) and in the absence of NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BRMEA1^T formed a lineage within the genus Neobacillus (family Bacil-laceae) and showed the highest sequence similarity to Neobacillus drentensis DSM 15600^T (98.3%) and Neobacillus fumarioli KCTC 13885^T (98.2%), and less than 98.2% 16S rRNA gene sequence similarity to the other members of the genus Neobacillus. Whole-genome analysis of strain BRMEA1^T comprised a circular chromosome (5632809 bp in size) with 38.5mol% G+C content. Digital DNA–DNA hybridization analyses revealed that strain BRMEA1^T showed 20.5 and 22.0% genomic DNA relatedness with the closest species, N. drentensis DSM 15600^T and N. fumarioli KCTC 13885^T, respectively. The whole-genome sequence of strain BRMEA1^T showed the presence of 11 specific conserved signature indels for the genus Neobacillus. The major cellular fatty acids (>10%) of strain BRMEA1^T were found to be iso-C_15:0 and anteiso-C_15:0, while the major polar lipids were found to be diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. Polyphasic analysis results revealed that BRMEA1^T represents a novel species of the genus Neobacillus, with the proposed name Neobacillus endophyticus sp. nov. The type strain is BRMEA1^T (=KCTC 43208^T=CCTCC AB 2020071^T).