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Bacillus nakamurai sp. nov., a black-pigment-producing strain
- Dunlap, Christopher A., Saunders, Lauren P., Schisler, David A., Leathers, Timothy D., Naeem, Naveed, Cohan, Frederick M., Rooney, Alejandro P.
- International Journal of Systematic and Evolutionary Microbiology 2016 v.66 pp. 2987-2991
- Two isolates of a Gram-stain-positive, strictly aerobic, motile, rod-shaped, endospore-forming bacterium were identified during a survey of the Bacillus diversity of the Agriculture Research Service Culture Collection. These strains were originally isolated from soil and have a phenotype of producing a dark pigment on tryptic soy agar. Phylogenetic analysis of the 16S rRNA gene indicated that these strains were related most closely to Bacillus subtilis subsp. inaquosorum (99.7% similarity) and Bacillus axarquiensis (99.7 %). In phenotypic characterization, the novel strains were found to grow between 17 and 50 _C and can tolerate up to 9% (w/v) NaCl. Furthermore, the strains grew in media of pH 5.5–10 (optimal growth at pH 7.0–8.0). The predominant cellular fatty acids were anteiso-C15 : 0 (34.8 %) and iso-C15 : 0 (21.9 %). The cell-wall peptidoglycan contained meso-diaminopimelic acid. A draft genome of both strains was completed. The DNA G+C content was 43.8 mol%. A phylogenomic analysis on the core genome of these two new strains and all members of the Bacillus subtilis group revealed these two strains formed a distinct monophyletic clade with the nearest neighbour Bacillus amyloliquefaciens. DNA–DNA relatedness studies using in silico DNA–DNA hybridizations showed the two strains were conspecific (93.8 %), while values with all other species (<31.5 %) were well below the species threshold of 70 %. Based on the consensus of phylogenetic and phenotypic analyses, these strains are considered to represent a novel species within the genus Bacillus, for which the name Bacillus nakamurai sp. nov. is proposed, with type strain NRRL B-41091T (=CCUG 68786T).