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We announce the draft genome sequence of three Gram-negative bacteria isolated from coral tissues affected with the black band disease (BBD), identified with the NCBI's Assembly Database accession numbers: MBQF, MAYB and MBQE. These genome drafts constitute an useful tool for the characterisation of these bacteria and for the understanding of the relationship between the microbial consortia associated with the disease and the onset and progression of the pathology.

This is the taxonomic study of a novel bacterial strain, designated GSS14T, isolated from a sediment sample of Yuncheng Salt Lake, China. Cells were Gram-negative, ovoid to rod-shaped and motile by means of flagella. The isolate could grow at 10–45 °C, at pH 6.5–11.0 and in the presence of 0–12 % (w/v) NaCl. The dominant fatty acids were summed feature 8 (consisting of C18 : 1ω7c and/or C18 : 1ω6c; 76.7 %) and the DNA G+C content was 61 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain GSS14T was affiliated with the genus Nitratireductor , and it was most closely related to Nitratireductor kimnyeongensis KY 101T (98.2 % 16S rRNA gene sequence similarity) and Nitratireductor aquibiodomus JCM 21793T (96.6 %). DNA–DNA hybridization between strains GSS14T and N. kimnyeongensis KY 101T revealed 52 % relatedness. Phenotypic, chemotaxonomic and phylogenetic data support assignment of this isolate to the genus Nitratireductor as a representative of a novel species. The name Nitratireductor lacus sp. nov. is proposed, with strain GSS14T (=KCTC 52186T=MCCC 1K02481) as the type strain.

A taxonomic study was carried out on a novel bacterial strain, designated C115T, isolated from a crude-oil-degrading consortium, enriched from deep-sea water of the Indian Ocean. Cells were Gram-negative short rods, mobile by means of a monopolar flagellum. Growth was observed at salinities of 0–7 % and at 10–43 °C. It was unable to degrade Tween 80 or gelatin. 16S rRNA gene sequence analysis showed that strain C115T was related most closely to Nitratireductor aquibiodomus NL21T (96.5 % similarity), Nitratireductor kimnyeongensis KY 101T (96.4 %) and Nitratireductor basaltis J3T (96.2 %). The predominant fatty acids were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c, 81.8 %) and C18 : 0 (7.0 %). The G+C content of the chromosomal DNA of strain C115T was 59 mol%. Based on its morphology, physiology and fatty acid composition together with 16S rRNA gene sequence comparisons, the novel strain most appropriately belongs to the genus Nitratireductor, but can be distinguished readily from recognized species of the genus. Strain C115T is therefore considered to represent a novel species of the genus Nitratireductor, for which the name Nitratireductor indicus sp. nov. is proposed. The type strain is C115T (=RC92-7T =CCTCC AB 209298T =LMG 25540T =MCCC 1A01260T).

A Gram-negative, coccoid- or rod-shaped bacterium was isolated from black sand collected from Soesoggak beach, Jeju Island, Korea. The isolate, designated J3T, grew at 15-45 degrees C, at pH 5.5-10.0 and in 0-8 % NaCl. It was oxidase- and catalase-positive. Strain J3T reduced nitrate to nitrite, but did not reduce nitrite to nitrogen gas. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain J3T was closely related to Nitratireductor aquibiodomus NL21T and belonged to the genus Nitratireductor. Major cellular fatty acids were C(18 : 1)omega7c (82.0 %), C(19 : 0)omega8c cyclo (4.3 %) and C(18 : 0) (4.0 %), a profile that is typical of members of the genus Nitratireductor and distinct from those of other genera in the family Phyllobacteriaceae. Differences in physiological characteristics and fatty acid profiles, as well as low DNA-DNA hybridization values, further established that strain J3T was distinct from N. aquibiodomus NL21T. Thus, strain J3T (=KCTC 22119T =JCM 14935T) should be classified as the type strain of a novel species in the genus Nitratireductor, for which the name Nitratireductor basaltis sp. nov. is proposed.

The Montreal Biodome operates a methanol-fed denitrification system that treats the water in its three million litre marine mesocosm. An unknown bacterium, named strain NL21T, was isolated from this system on TSA and R2A agar. The organism is a Gram-negative, rod-shaped (1×3 μm) facultative aerobe. Optimal growth conditions on R2A agar are 30–35 °C, pH 7–7·5 and 1 % (w/w) NaCl. Phylogenetic analysis of the 16S rDNA sequence reveals that strain NL21T forms a novel lineage in the family ‘Phyllobacteriaceae’ within the α2 subgroup of the Proteobacteria. The closest related genera are Aminobacter, Pseudaminobacter, Mesorhizobium and Defluvibacter. Major cellular fatty acids are C18 : 1 ω7c (75 %), C19 : 0 ω8c cyclopropane (9·4 %) and C18 : 0 (4·2 %). The DNA G+C content of strain NL21T (57 mol%) differs from those of all other described members of the ‘Phyllobacteriaceae’ (60–64 mol%). Strain NL21T reduces nitrate to nitrite, but does not reduce nitrite to nitrogen gas. Only a few sugars and amino acids can serve as carbon sources. Strain NL21T is able to grow without salt and tolerates up to 5 % NaCl. Phylogenetic analysis, as well as physiological and biochemical tests, showed that strain NL21T was different from all other members of the ‘Phyllobacteriaceae’ with validly published names. Strain NL21T therefore represents a novel genus, for which the name Nitratireductor aquibiodomus gen. nov., sp. nov. is proposed, with the type strain NL21T (=DSM 15645T=ATCC BAA-762T).

A straw-yellow pigmented bacterium, strain IITR-21(T) was isolated from a pesticide contaminated site and characterized by using a polyphasic taxonomic approach. The organism had morphological and chemotaxonomic properties consistent with its classification in the genus Nitratireductor. Phylogenetic analysis of the 16S rRNA gene sequence showed that the strain IITR-21(T) belongs to the genus Nitratireductor and was moderately related to Nitratireductor indicus C115(T) (97.7%) and Nitratireductor pacificus pht-3B(T) (97.4%), whereas sequence similarity value with the other species including the type species of the genus Nitratireductor, Nitratireductor aquibiodomus showed less than 97.0% similarity. However, the DNA-DNA relatedness values between strain IITR-21(T) and the moderately related taxa N. indicus (59.1%) and N. pacificus (40.4%) were well below the 70% threshold value recommended for the delineation of bacterial species. The G+C content of the DNA was 62.4 mol%. Based on physiological, biochemical tests and genotypic differences between the strain IITR-21(T) and the other two validly published species of the genus Nitratireductor, it is proposed that the strain be classified as a new species of Nitratireductor as Nitratireductor lucknowense sp. nov. The type strain is IITR-21(T) (=MTCC 8354(T )= DSM 24322(T)).

Two Gram-negative-staining, aerobic bacterial strains, designated CL-SC21T and CL-SC22, were isolated from a culture of the diatom Skeletonema costatum (Korean Marine Microalgae Culture Center, KMMCC strain B-396) established from the East Sea, Korea. The two novel strains shared 99.9 % 16S rRNA gene sequence similarity. Analysis of the 16S rRNA gene sequences showed an affiliation with the genus Nitratireductor, with the strains sharing 96.5–97.5 % similarity with the type strains of recognized species of the genus Nitratireductor and being most closely related to Nitratireductor aquibiodomus NL21T. Phylogenetic analyses of the 16S rRNA gene sequences showed that strain CL-SC21T together with strain CL-SC22 belonged to the genus Nitratireductor and formed a robust clade among closely related Nitratireductor species. The polar lipids comprised phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, two unidentified aminophospholipids, an unidentified aminolipid, an unidentified phospholipid and five unidentified lipids. Ubiquinone 10 was the major quinone. The major cellular fatty acids of strains CL-SC21T and CL-SC22 were C18 : 1ω7c (70.6–72.3 %) and C19 : 0ω8c cyclo (10.9–11.8 %). The genomic DNA G+C contents of strains CL-SC21T and CL-SC22 were 56.7 and 57.1 mol%, respectively. The level of DNA–DNA relatedness between strains CL-SC21T and CL-SC22 was 86 % (reciprocal 91 %), indicating that the two isolates represented a single species. However, levels of DNA–DNA relatedness between N. aquibiodomus NL21T and strains CL-SC21T and CL-SC22 were 28 % (reciprocal 45 %) and 25 % (reciprocal 50 %), respectively. Phylogenetic analysis and the results of biochemical tests showed that strains CL-SC21T and CL-SC22 were different from all recognized species of the genus Nitratireductor. Thus, strains CL-SC21T and CL-SC22 represent a novel species of the genus Nitratireductor, for which the name Nitratireductor aquimarinus sp. nov. is proposed. The type strain is CL-SC21T ( = KCCM 90090T = JCM 17288T).

Strain pht-3BT was isolated from a pyrene-degrading consortium of an enriched sediment from the Pacific Ocean, collected during the screening of polycyclic aromatic hydrocarbon-degrading bacteria. Cells were Gram-negative, short rods that were motile by means of flagella. Growth was observed at 0–7 % NaCl and 10–41 °C. The isolate was able to reduce nitrate to nitrite, but not to nitrogen. 16S rRNA gene sequence comparisons showed that strain pht-3BT was most closely related to Nitratireductor aquibiodomus NL21T (97.3 % 16S rRNA gene sequence similarity), N. indicus C115T (97.1 %), N. basaltis J3T (96.8 %) and N. kimnyeongensis KY 101T (96.7 %). DNA–DNA hybridization between strain pht-3BT and these reference strains revealed 55, 54, 28 and 42 % DNA–DNA relatedness, respectively. The dominant fatty acids were C19 : 0ω8c cyclo (22.6 %) and summed feature 8 (consisting of C18 : 1ω7c and/or C18 : 1ω6c; 60.4 %). The G+C content of the chromosomal DNA was 63 mol%. These characteristics were in good agreement with those of members of the genus Nitratireductor. According to cell morphology, physiology, fatty acid composition, 16S rRNA gene sequence analysis and DNA–DNA relatedness, the isolate belonged to the genus Nitratireductor but could be readily distinguished from recognized species of the genus. Therefore a novel species is proposed to accommodate strain pht-3BT, for which the name Nitratireductor pacificus sp. nov. is proposed. The type strain is pht-3BT ( = CCTCC AB 209302T = LMG 25541T = MCCC 1A01024T).

The genus Nitratireductor represents nitrate-reducing bacteria from the family Phyllobacteriaceae . Here we report the draft genome sequence of Nitratireductor aquibiodomus strain RA22, which contains 4,592,790 bp, with a G+C content of 61.30%, and has 4,241 protein coding genes.