Taxonomic Relationship of Black-Pigmented Bacillus subtilis Strains and a Proposal for Bacillus atrophaeus sp. nov. Nakamura, L. K.,, 39, 295-300 (1989), doi = https://doi.org/10.1099/00207713-39-3-295, publicationName = Microbiology Society, issn = 1466-5026, abstract= Abstract The taxonomic position of Bacillus subtilis strains that produce soluble black pigment is unclear. To assess the genetic relatedness between the pigmented and nonpigmented strains, deoxyribonucleic acid (DNA) reassociation was measured spectrophotometrically. Among the 40 pigmented strains examined, two distinct DNA relatedness groups were found. A total of 25 strains (group 1) showed 24 to 34% DNA relatedness and 15 strains (group 2) showed 70 to 100% relatedness to Bacillus subtilis type strain NRRL NRS-744. The intragroup DNA relatedness values for each group ranged from 85 to 100%; the intergroup relatedness values ranged from 20 to 35%. A multilocus enzyme electrophoresis analysis revealed a low level of similarity between group 1 and group 2 or the nonpigmented group. The group 2 strains and the nonpigmented strains clustered in a common group, indicating the close genetic relationship of these organisms. My results strongly suggest that group 2 is a pigmented variant of B. subtilis, but group 1 is a new species, for which the name Bacillus atrophaeus is proposed. The type strain of the new species is strain NRRL NRS-213., language=, type=