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Sporulene, a pentacyclic triterpenoid, was discovered in Bacillus subtilis and is associated with bacterial endospores. However, the study was not further extended, leaving a trail of questions. One such question is what diversity of sporulenes exists among spore-forming members? Considering the sporulene biosynthesis pathway as a fundamental tool to survey the distribution of this molecule, a genome mining study was conducted. Mining for genes encoding putative proteins of sporulene biosynthesis pathway among the class Bacilli members revealed the presence of hepS, hepT, ytpB, and sqhC genes in the members of the family Bacillaceae, Caryophanaceae, Paenibacillaceae, and Sporolactobacillaceae. However, these genes were completely absent in the members of Staphylococcaceae, Lactobacillaceae, Aerococcaceae, Carnobacteriaceae, and Leuconostocaceae. Unlike other probable pathway related proteins, a conserved amino acid domain of putative terpenoid cyclase (YtpB) appeared deep-rooted among the genus Bacillus members. In-depth analysis showed the constant gene arrangement of hepS, hepT, ytpB, and sqhC genes in these members, there by demonstrating the conserved nature of sporulene biosynthesis pathway in the members of the genus Bacillus. Our study suggests confinement of the sporulene biosynthesis pathway to spore-forming members of the class Bacilli, majorly to the genus Bacillus., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Strain JC267T was isolated from pebbles collected from Pingleshwar beach, Gujarat, India. Cells are Gram-stain-positive, facultatively anaerobic, non-motile rods forming sub-terminal endospores in swollen ellipsoidal to oval sporangia. Strain JC267T contains anteiso-C15 : 0, iso-C15 : 0, iso-C14 : 0, iso-C16 : 0, C16 : 0 and anteiso-C17 : 0 as major (>5 %) cellular fatty acids. Polar lipids include phosphatidylglycerol, phospholipids (PL1-3), glycolipids (GL1-2) and an unidentified lipid. Cell-wall amino acids are composed of diagnostic meso-diaminopimelic acid, dl-alanine and a small amount of d-glutamic acid. The genomic DNA G+C content of strain JC267T is 45.5 mol%. The 16S rRNA gene sequence of strain JC267T showed highest sequence similarities of < 98.41 % with all species of the genus Bacillus when subjected to EzTaxon-e blast analysis. The reassociation values based on DNA-DNA hybridization of strain JC267T with Bacillus halosaccharovorans IBRC-M 10095T and Bacillus niabensis JCM 16399T were 26 ± 1 % and 34 ± 3 %, respectively. Based on taxonomic data obtained using a polyphasic approach, strain JC267T represents a novel species of the genus Bacillus, for which the name Bacillus endolithicus sp. nov. is proposed. The type strain is JC267T ( = IBRC-M 10914T = KCTC 33579T).

Two novel Gram-stain-positive, rod-shaped, non-motile, non-endospore-forming bacterial strains, S7T and IB5, were isolated from Khavda, India. Based on 16S rRNA gene sequence analysis they were identified as belonging to the class Bacilli, order Bacillales, family Bacillaceae, and were most closely related to Bacillus qingdaonensis CGMCC 1.6134T (97.3 %, sequence similarity), Bacillus halochares LMG 24571T (96.9 %), Bacillus salarius KCTC 3912T (95.6 %) and Bacillus aidingensis DSM 18341T (95.3 %). However, these strains shared only 88.2 % 16S rRNA gene sequence similarity with Bacillus subtilis subsp. subtilis DSM 10T, indicating that strains S7T and IB5 might not be members of the genus Bacillus. The DNA-DNA relatedness of these strains with B. qingdaonensis CGMCC 1.6134T was 42.9 ± 0.8. The cell-wall peptidoglycan of strains S7T and IB5 contained meso-diaminopimelic acid, while the polar lipids included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, a phospholipid and three unknown lipids. The predominant isoprenoid quinone was MK-7. anteiso-C15 : 0 was the predominant fatty acid. The results of the phylogenetic, chemotaxonomic and biochemical tests allowed a clear differentiation of strains S7T and IB5, suggesting that they represent a novel member of the family Bacillaceae, for which the name Salibacterium halotolerans gen. nov., sp. nov. is proposed. The type strain of Salibacterium halotolerans is S7T ( = KCTC 33658T = CGMCC 1.15324T). Based on the results of the present study, it is also suggested that B. qingdaonensis and B. halochares should be transferred to this novel genus, as Salibacterium qingdaonense comb. nov. and Salibacterium halochares comb. nov., respectively.

Two bacterial strains (JC247T and JC248) were isolated from soil samples collected from Rann of Kutch, Gujarat, India. Colonies of both strains were creamy white. Cells were Gram-stain-positive, rods-to-curved rods (crescent-shaped), and produced centrally located oval-shaped endospores. Major (>5 %) fatty acids of both strains were iso-C16  :  0, iso-C14  :  0, iso-C15  :  0, C16  :  1ω11c and C16  :  0, with minor ( < 5 but >1 %) amounts of anteiso-C15  :  0, anteiso-C17  :  0, iso-C16  :  1 H, iso-C17  :  0, iso-C18  :  0, C14  :  0, C17  :  0, C18  :  0, C18  :  1ω9c, iso-C17  :  1ω10c and anteiso-C17  :  0B/isoI. Diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol were the major polar lipids of both strains. Cell-wall amino acids were l-alanine, d-alanine, d-glutamic acid and meso-diaminopimelic acid. The genomic DNA G+C content of strains JC247T and JC248 was 48.2 and 48.1 mol%, respectively. Both strains were closely related with mean DNA-DNA hybridization >90 %. 16S rRNA gene sequence analysis of both strains indicated that they are members of the genus Bacillus within the family Bacillaceae of the phylum Firmicutes. Both strains had a 16S rRNA gene sequence similarity of 96.93 % with Bacillus firmus NCIMB 9366T and < 96.92 % with other members of the genus Bacillus. Sequence similarity between strain JC247T and JC248 was 100 %. Distinct morphological, physiological and genotypic differences from previously described taxa support the classification of strains JC247T and JC248 as representatives of a novel species of the genus Bacillus, for which the name Bacilluscrescens sp. nov. is proposed. The type strain is JC247T ( = KCTC 33627T = LMG 28608T).

Two Gram-stain-positive, diesel oil-degrading, solvent-tolerant, aerobic, endospore-forming, rod-shaped bacteria were isolated from a contaminated laboratory plate. Based on 16S rRNA gene sequence analysis, strains JC228(T) and JC279 were identified as belonging to the genus Bacillus within the family Bacillaceae of the phylum Firmicutes and were found to be most closely related to Bacillus carboniphilus JCM 9731(T) (98.1% 16S rRNA gene sequence similarity) and shared <96.0% 16S rRNA gene sequence similarity with other members of the genus Bacillus . The DNA-DNA hybridization value between the two strains was 88±2%. Strain JC228(T) showed 23.4±1% reassociation (based on DNA-DNA hybridization) with B. carboniphilus LMG 18001(T). The DNA G+C content of strains JC228(T) and JC279 was 39 and 38.4 mol%, respectively. Both strains were positive for catalase and oxidase activities, and negative for hydrolysis of starch and Tween 80. Strains JC228(T) and JC279 grew chemoorganoheterotrophically with optimum growth at pH 7 (range pH 7-9.5) and 35 °C (range 25-40 °C). Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and an unidentified phospholipid (PL2) were the major polar lipids. Major cellular fatty acids were iso-C(15 : 0), anteiso-C(15 : 0), iso-C(17 : 0) and C(16 : 0). Whole-cell hydrolysates contained l-alanine, d-alanine, d-glutamic acid and meso-diaminopimelic acid. Both strains utilized diesel oil as sole carbon and energy source. The results of physiological, biochemical, chemotaxonomic and molecular analyses allowed clear differentiation of strains JC228(T) and JC279 from their closest phylogenetic neighbours. Therefore strains JC228(T) and JC279 represent a novel species of the genus Bacillus , for which the name Bacillus oleivorans sp. nov. is proposed. The type strain is JC228(T) ( = LMG 28084(T) = CCTCC AB 2013353(T))., (© 2015 IUMS.)

A novel Gram-stain-positive, rod-shaped, motile and endospore-forming novel bacterial strain 25nlg(T) was isolated from Lonar soda lake, in India. Based on the 16S rRNA gene sequence analysis, it was identified as a member of Firmicutes, being most closely related to Bacillus patagoniensis PAT 05(T) (96.6 %) and other members in the genus Bacillus (<96.0 %). Strain 25nlg(T) was catalase and oxidase-positive. The strain grows optimally at a pH of 9.5 with 4-6 % (w/v) NaCl and temperature of 35-37 °C. The cell wall of the strain 25nlg(T) contains meso-diaminopimelic acid as the diagnostic amino acid. Polar lipids include diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unknown phospholipid (PL2), an aminophospholipid (APL2) and three unknown lipids (L2-4). The predominant isoprenoid quinone was MK-7. iso-C15:0 (41.7 %) was the predominant fatty acid, and significant proportions of anteiso-C15:0 (20.8 %), C12:0 (5.5 %), anteiso-C17:0 (4.9 %), iso-C17:0 (4.5 %) were also detected in the strain 25nlg(T). The DNA G+C content of the strain 25nlg(T) was 40.5 mol%. The results of molecular, physiological and biochemical tests allowed a clear phenotypic differentiation of strain 25nlg(T) from all other members of the genus Bacillus. Strain 25nlg(T) represents a novel member of the genus Bacillus, for which the name Bacillus lonarensis sp. nov. is proposed. The type strain is 25nlg(T) (=KCTC 33413(T) = LMG 27974(T) = CGMCC = 1.12817(T)).

Two bacterial strains (JC167T and JC168) were isolated from a soil sample collected from Mandpam, Tamilnadu, India. Colonies of both strains were orange and cells Gram-stain-positive. Cells were small rods, and formed terminal endospores of ellipsoidal to oval shape. Both strains were positive for catalase, oxidase and hydrolysis of starch/gelatin, and negative for chitin hydrolysis, H2S production, indole production and nitrate reduction activity. Major fatty acids of both strains (>5%) were anteiso-C15:0, iso-C16:0, iso-C15:0, anteiso-C17:0, iso-C14:0 and C16:0 with minor (<5 but >1%) amounts of iso-C17:0, anteiso-C17:0 B/iso-C17:0 I and C16:1ω11c. Diphosphatydilglycerol, phosphatidylethanolamine and phosphatidylglycerol were the major polar lipids of both strains. Cell wall amino acids were L-alanine, D-alanine, D-glutamic acid and meso-diaminopimelic acid. β-Carotene and five unidentified carotenoids were present in both strains. Mean genomic DNA G+C content was 53.4±1 mol% and the two strains were closely related (mean DNA-DNA hybridization>90%). 16S rRNA gene sequence comparisons of both strains indicated that they represent species of the genus Bacillus within the family Bacillaceae of the phylum Firmicutes. Both strains had a sequence similarity of 97.6% with Bacillus saliphilus 6AGT and <96.8% with other members of the genus Bacillus. Sequence similarity between strain JC167T and 168 was 100%. Strain JC167T showed 25.8±1% reassociation (based on DNA-DNA hybridization) with B. saliphilus DSM 15402T (=6AGT). Distinct morphological, physiological and genotypic differences from previously described taxa support the classification of strain JC167T as a representative of a novel species of the genus Bacillus, for which the name Bacillus luteus sp. nov. is proposed. The type strain is JC167T (=KCTC 33100T=LMG 27257T).

Polycyclic aromatic hydrocarbons are a group of compounds that pose threat to humans and animal life. Methods to reduce the amount of PAHs in the environment are continuously being sought. The bacterial consortium capable of utilizing benzo(a)pyrene as the sole source of carbon and energy was isolated from petrochemical soil. The isolates were identified as Bacillus cereus and Bacillus viretibased on morphological characterization, and 16S rDNA gene sequence analysis. About 58.98% of benzo(a)pyrene at concentration of 500 mg l(-1) in mineral salts medium were removed by bacterial consortium. GC mass spectral analysis showed the presence of metabolite cis-4-(7-hydroxypyren-8-yl)-2-oxobut-3enoic acid. The results indicate that the bacterial consortium is a new bacterial resource for biodegrading benzo(a)pyrene and might be used for bioremediation of sites heavily contaminated by benzo[a]pyrene and its derivatives.