Bacillus velezensis was previously reported to be a later heterotypic synonym of Bacillus amyloliquefaciens, based primarily on DNA–DNA relatedness values. We have sequenced a draft genome of B. velezensis NRRL B-41580T. Comparative genomics and DNA–DNA relatedness calculations show that it is not a synonym of B. amyloliquefaciens. It was instead synonymous with Bacillus methylotrophicus. ‘Bacillus oryzicola’ is a recently described species that was isolated as an endophyte of rice (Oryza sativa). The strain was demonstrated to have plant-pathogen antagonist activity in greenhouse assays, and the 16S rRNA gene was reported to have 99.7 % sequence similarity with Bacillus siamensis and B. methylotrophicus, which are both known for their plant pathogen antagonism. To better understand the phylogenetics of these closely related strains, we sequenced the genome of ‘B. oryzicola’ KACC 18228. Comparative genomic analysis showed only minor differences between this strain and the genomes of B. velezensis NRRL B-41580T, B. methylotrophicus KACC 13015T and Bacillus amyloliquefaciens subsp. plantarum FZB42T. The pairwise in silico DNA–DNA hybridization values calculated in comparisons between the strains were all greater than 84 %, which is well above the standard species threshold of 70 %. The results of morphological, physiological, chemotaxonomic and phylogenetic analyses indicate that the strains share phenotype and genotype coherence. Therefore, we propose that B. methylotrophicus KACC 13015T, B. amyloliquefaciens subsp. plantarum FZB42T, and ‘B. oryzicola’ KACC 18228 should be reclassified as later heterotypic synonyms of B. velezensis NRRL B-41580T, since the valid publication date of B. velezensis precedes the other three strains.

The taxonomic characteristics of two bacterial strains, FH5^T and SS4, isolated from enrichment cultures obtained from two distinct marine environments, were determined. These bacteria were Gram-stain-negative, facultatively anaerobic rods. Growth occurred at 20–40 °C (optimum, 28–32 °C), pH 5.5–9.0 (optimum, pH 7.0–7.5) and in the presence of 1–7 % NaCl (optimum, 2–4 %). The major cellular fatty acids were anteiso-C_15 : 0 and iso-C_15 : 0. Menaquinone 7 (MK-7) was the sole respiratory quinone. The major polar lipids were phosphatidylethanolamine, an unkown phospholipid and an unknown lipid. The DNA G+C contents of strains FH5^T and SS4 were both determined to be 42.0 mol%. The results of DNA–DNA hybridization studies indicated that the FH5^T and SS4 genomes share greater than 95 % relatedness. The strains formed a distinct phyletic line within the class Bacteroidia , with less than 89.4 % sequence similarity to their closest relatives with validly published names. On the basis of physiological and biochemical characteristics, 16S rRNA gene sequences and chemical properties, a novel genus and species, Draconibacterium orientale gen. nov., sp. nov., within the class Bacteroidia , are proposed, with strain FH5^T ( = DSM 25947^T = CICC 10585^T) as the type strain. In addition, a new family, Draconibacteriaceae fam. nov., is proposed to accommodate Draconibacterium gen. nov.

Iturins and closely related lipopeptides constitute a family of antifungal compounds known as iturinic lipopeptides that are produced by species in the Bacillus subtilis group. The compounds that comprise the family are: iturin, bacillomycin D, bacillomycin F, bacillomycin L, mycosubtilin, and mojavensin. These lipopeptides are prominent in many Bacillus strains that have been commercialized as biological control agents against fungal plant pathogens and as plant growth promoters. The compounds are cyclic heptapeptides with a variable length alkyl sidechain, which confers surface activity properties resulting in an affinity for fungal membranes. Above a certain concentration, enough molecules enter the fungal cell membrane to create a pore in the cell wall, which leads to loss of cell contents and cell death. This study identified 330 iturinic lipopeptide clusters in publicly available genomes from the B. subtilis species group. The clusters were subsequently assigned into distinguishable types on the basis of their unique amino acid sequences and then verified by HPLC MS/MS analysis. The results show some lipopeptides are only produced by one species, whereas certain others can produce up to three. In addition, four species previously not known to produce iturinic lipopeptides were identified. The distribution of these compounds among the B. subtilis group species suggests that they play an important role in their speciation and evolution.