Brachybacterium aquaticum sp. nov., a novel actinobacterium isolated from seawater.

A pale-yellowish bacterium, strain KWS-1T, was isolated from seawater during a study of the bacterial diversity of the marine environment of the Kanyakumari coastal region of the Bay of Bengal, India, and was studied by using a polyphasic taxonomic approach. Strain KWS-1T had morphological and chemotaxonomic properties (cell-wall diamino acid, menaquinone and fatty acid profile) consistent with its classification in the genus Brachybacterium. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain KWS-1T was related most closely to Brachybacterium paraconglomeratum JCM 17781T, followed by Brachybacterium saurashtrense DSM 23186T, Brachybacterium gingengisoli JCM 19356T, Brachybacterium faecium JCM 11609T and Brachybacterium conglomeratum JCM 11608T (98.45, 98.24, 98.12, 98.10 and 98.10 % similarity, respectively), whereas the sequence similarity values with respect to the other Brachybacterium species with validly published names were between 97.4 and 94.2 %. However, the DNA-DNA hybridization values between strain KWS-1T and the five most closely related species were less than the threshold value for species discrimination. The major lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylserine and the major quinone was menaquinone MK-7. The DNA G+C content of strain KWS-1T was 71.8 mol%. The above data in combination with the phenotypic distinctiveness of strain KWS-1T from other reference strains clearly indicate that the strain represents a novel species, for which the name Brachybacterium aquaticum sp. nov. is proposed. The type strain is KWS-1T (=MTCC 11836T=DSM 28796T=JCM 30059T).

Reclassification of Bacillus isronensisShivaji et al. 2009 as Solibacillus isronensis comb. nov. and emended description of genus Solibacillus Krishnamurthi et al. 2009.

An investigation into the taxonomic position of Bacillus isronensis MTCC 7902T revealed that the strain shares a common phylogenetic lineage with Solibacillus silvestris MTCC 10789T. It displays considerable overlap in phenotypic properties with the genus Solibacillus, including endospore shape and position, oxidase and catalase activities, presence of iso-C15 : 0, C16 : 1ω7c alcohol and iso-C17 : 1ω7c as major cellular fatty acids, A4α-type cell-wall peptidoglycan, polar lipids and menaquinone pattern. These features reinforce the findings of molecular phylogenetic analyses based on 16S rRNA gene, gyrB gene and 16S-23S internal transcribed spacer (ITS) region sequences and, in line with the recommendations of Kämpfer et al. [Int J Syst Evol Microbiol 56 (2006), 781-786], provide justification for the transfer of Bacillus isronensis from the genus Bacillus to Solibacillus as Solibacillus isronensis comb. nov. The type strain is B3W22T ( = MTCC 7902T = DSM 21046T = JCM 13838T). An emended description of the genus Solibacillus is also provided.

Tamilnaduibacter salinus gen. nov., sp. nov., a halotolerant gammaproteobacterium within the family Alteromonadaceae, isolated from a salt pan in Tamilnadu, India.

Two novel Gram-stain-negative, slow-growing, halotolerant strains with rod-shaped cells, designated as strains Mi-7T and Mi-8, which formed pin-point colonies on halophilic media were isolated during a study into the microbial diversity of a salt pan in the state of Tamilnadu, India. Both the strains had an obligate requirement for 1 % (w/v) NaCl for growth and were halotolerant, growing at NaCl concentrations of up to 20 % (w/v) in media. The strains, however, showed an inability to utilize the majority of substrates tested as sole carbon sources for growth and in fermentation reactions. Molecular phylogenetic analyses, based on 16S rRNA gene sequence revealed their closest phylogenetic neighbours to be members of the genus Marinobacter, with whom they showed the highest sequence similarity of 93.6 % and even less with the type strain of the type species, Marinobacter hydrocarbonoclasticus DSM 8798T (91.1 %). Similarities with other genera within the family Alteromonadaceae were below 91.0 %. However, the two strains were very closely related to each other with 99.9 % sequence similarity, and DNA­DNA hybridization analyses confirmed their placement in the same species. The DNA G+C content of both strains was 65 mol%. Using the polyphasic taxonomic data obtained from this study, strains Mi-7T and Mi-8 represent two strains of the same species of a novel genus for which the name Tamilnaduibacter salinus gen. nov., sp. nov., is proposed; the type strain of the novel species is Mi-7T ( = MTCC 12009T = DSM 28688T).

Microbacterium enclense sp. nov., isolated from sediment sample.

A novel bacterium (strain NIO-1002(T)) belonging to the genus Microbacterium was isolated from a marine sediment sample in Chorao Island, Goa Province, India. Its morphology, physiology, biochemical features and 16S rRNA gene sequence were characterized. Cells of this strain were Gram-stain-positive, non-motile, non-spore-forming rods that formed yellow-pigmented colonies. It grew in 0-12% (w/v) NaCl and at 25-37 °C, with optimal growth at 30 °C. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NIO-1002(T) is associated with members of the genus Microbacterium, with highest sequence similarity with Microbacterium hominis CIP 105731(T) (98.1%) and Microbacterium testaceum KCTC 9103(T) (98.0%). Within the phylogenetic tree, this novel strain shared a branching point with M. hominis CIP 105731(T). The DNA G+C content was 66.5 mol% and DNA-DNA hybridization relatedness between NIO-1002(T), M. hominis CIP 105731(T) and M. testaceum KCTC 9103(T) was 39.0 ± 2.0% and 41.0 ± 2.0%, respectively. The major fatty acids were ai-C15 : 0, i-C16 : 0 and ai-C17 : 0 and the diamino acid in the cell-wall peptidoglycan of NIO-1002(T) was lysine. Data obtained from DNA-DNA hybridization and chemotaxonomic phenotypic analysis support the conclusion that strain NIO-1002(T) represents a novel species within the genus Microbacterium. The name Microbacterium enclense sp. nov. is proposed, with NIO-1002(T) ( = NCIM 5454(T) = DSM 25125(T) = CCTCC AB 2011120(T)) as the type strain.

Bacillus encimensis sp. nov. isolated from marine sediment.

A Gram-stain-positive, rod-shaped, endospore-forming, aerobic bacterium designated SGD-V-25(T) was isolated from Veraval sediment sample, India. Strain SGD-V-25(T) was capable of growing at 25-50 °C (optimum 37 °C), pH 6-12 (optimum pH 7.0) and with 0-5% (w/v) NaCl. The taxonomic position of this strain was deduced using a polyphasic approach and the 16S rRNA gene sequence analysis showed that the isolate belongs to the phylum Firmicutes , forming the cluster with Bacillus badius MTCC 1548(T), with which it shares highest similarity of 99.1% with 13 nt differences. Other type strains of the genus Bacillus showed less than 96% similarity. The cell wall contained meso-diaminopimelic acid as the diagnostic diamino acid. The polar lipid profile of strain SGD-V-25(T) showed the presence of diphosphatidylglycerol, phosphatidylglycerol, phsophoglycolipid and two aminophospholipids. The predominant isoprenoid quinone was MK-7. The major cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0, anteiso-C17 : 0, iso-C16 : 0, C16 : 1ω11c and C16 : 0. The genomic DNA G+C content of strain SGD-V-25(T) was 37.6 mol%. On the basis of phenotypic characteristics, phylogenetic analysis and DNA-DNA hybridization, strain SGD-V-25(T) could be clearly distinguished from closely related members of the genus Bacillus , and the name Bacillus encimensis sp. nov., is proposed to accommodate this strain. The type strain is SGD-V-25(T) ( =NCIM 5513(T) =DSM 28241(T)).

Exiguobacterium enclense sp. nov., isolated from sediment.

A Gram-stain-positive bacterium, designated strain NIO-1109(T), was isolated from a marine sediment sample from Chorao Island, Goa, India. Phenotypic and chemotaxonomic characteristics and data from phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NIO-1109(T) was related to the genus Exiguobacterium . Strain NIO-1109(T) exhibited >98.0% 16S rRNA gene sequence similarity with respect to Exiguobacterium indicum HHS 31(T) (99.5%) and Exiguobacterium acetylicum NCIMB 9889(T) (99.1%); the type strains of other species showed <98% similarity. Levels of DNA-DNA relatedness between strain NIO-1109(T) and E. acetylicum DSM 20416(T) and E. indicum LMG 23471(T) were less than 70% (33.0 ± 2.0 and 37 ± 3.2%, respectively). Strain NIO-1109(T) also differed from these two closely related species in a number of phenotypic traits. Based on phenotypic, chemotaxonomic and phylogenetic data, strain NIO-1109(T) is considered to represent a novel species of the genus Exiguobacterium , for which the name Exiguobacterium enclense sp. nov. is proposed. The type strain is NIO-1109(T) ( =NCIM 5457(T) =DSM 25128(T)  = CCTCC AB 2011124(T)).