- Volume 67, Issue 2, 2017

A novel endophytic bacterium, designated strain EGI 6500252T, was isolated from the surface-sterilized roots of a medicinal plant (Capparis spinosa L.) collected from Urumqi city, Xinjiang, north-west China. Cells were Gram-stain-positive, non-motile, aerobic, catalase- and oxidase-positive, rod-shaped and did not display spore formation. Strain EGI 6500252T grew at 10–40 °C (optimum 25–30 °C), at pH 6.0–8.0 (optimum pH 7.0) and in the presence of 0–10 % (w/v) NaCl (optimum 0–3 %). The major cellular fatty acids (>10 %) were identified as iso-C15 : 0, anteiso-C15 : 0, anteiso-C17 : 0 and summed feature 4. The predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, four unknown phospholipids, one unknown glycolipid and one unknown lipid. The dominant isoprenoid quinone was menaquinone 7 (MK-7). The DNA G+C content was 39.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain EGI 6500252T belonged to the genus Bacillus , and exhibited a highest 16S rRNA gene sequence similarity (96.2 %) that was lower than the suggested threshold (97.0 %) for separating bacterial species. On the basis of the phylogenetic analysis, chemotaxonomic data and physiological characteristics, strain EGI 6500252T represents a novel species of the genus Bacillus , for which the name Bacillus capparidis sp. nov. is proposed. The type strain is EGI 6500252T (=CGMCC 1.12820T=KCTC 33514T).

A novel thermophilic, anaerobic, chemolithoautotrophic bacterium, strain SF97T, was isolated from a terrestrial hot spring (Kuril Islands, Russia). Cells of strain SF97T were rod-shaped and motile with a Gram-positive cell-wall type. The novel isolate grew at 45–72 °C (optimum 65 °C) and pH 5.5–8.5 (optimum 6.0–6.5). The strain grew chemolithoautotrophically with molecular hydrogen as an electron donor, sodium sulfite or SO2 gas as an electron acceptor and bicarbonate/CO2 as a carbon source. Sulfate, thiosulfate, elemental sulfur, Fe(III) or nitrate were not used as electron acceptors either with H2 or organic electron donors. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belonged to the family Thermoanaerobacteraceae, order Thermoanaerobacterales , and was distantly related to species of the genus Ammonifex (92–93 % sequence similarity). On the basis of its physiological properties and results of phylogenetic analyses, strain SF97T is considered to represent a novel species of a new genus, for which the name Thermodesulfitimonas autotrophica gen. nov., sp. nov. is proposed. The type strain of Thermodesulfitimonas autotrophica is SF97T (=DSM 102936T=VKM B-2961T). T. autotrophica is the first reported obligate sulfite-reducing micro-organism.

Biochemical and molecular studies were performed on five unknown bacterial strains isolated from the intestinal contents of Northern Bobwhites (Colinus virginianus) collected from western Texas, USA. The strains were Gram-stain-positive, catalase-negative, non-spore-forming rods arranged in single cells, pairs or short chains. Colonies on Columbia blood agar are circular, flat, entire, approximately 0.5–1.5 mm in diameter and surrounded with a zone of alpha-haemolysis at after incubation for 48 h at 37 °C. Colonies on MRS agar are umbonate with irregular edge, opaque and approximately 1–1.5 mm in diameter after incubation for 48 h. The 16S rRNA gene sequences of the isolates were identical and the highest sequence similarity (97 %) was found to the type strains of Lactobacillus gasseri , L. johnsonii and L. taiwanensis . The strains were distinguishable from related species of the genus Lactobacillus on the basis of carbohydrate fermentation, enzymatic production and fatty acid profiles. The peptidoglycan type is l-Lys-d-Asp (A4α). The DNA G+C content is 35.6 mol%. Major cellular fatty acids are C14 : 0, C16 : 0 and C18 : 1 ω9c. Based on phenotypic, phylogenetic and chemotaxonomic information, the strains represent a novel species of the genus Lactobacillus for which the name Lactobacillus colini sp. nov. is proposed. The type strain is 111144 L1T (=DSM 101872T=KCTC 21086T).

A Gram-stain-positive, non-motile, coccus-shaped bacterium, designated strain C25T, was isolated from the soil beneath a decomposing pig carcass in Korea and was characterized using a polyphasic taxonomic approach. Comparative 16S rRNA gene sequence analysis showed that strain C25T belongs to the genus Vagococcus in the family Enterococcaceae of the Lactobacillales . 16S rRNA gene sequence analysis showed that strain C25T was closely related to Vagococcus lutrae CCUG 39187T (96.5 % similarity) and Enterococcus termitis LMG 8895T (95.8 %). The chemotaxonomic properties of strain C25T were consistent with those of the genus Vagococcus ; the major cellular fatty acids consisted of C16 : 0, C16 : 1 ω9c and C18 : 1 ω9c, and the cell-wall peptidoglycan type was based on meso-diaminopimelic acid. The G+C content of the genomic DNA was 44 mol%. On the basis of phylogenetic inference, fatty acid profile, and chemotaxonomic and other phenotypic properties, strain C25T is clearly differentiated from closely related type strains of the genus Vagococcus and represents a novel species in this genus, for which the name Vagococcus humatus sp. nov. is proposed. The type strain is C25T (=KEMB 562-002T=JCM 31581T).

An anaerobic, saccharolytic, spore-forming, butyrate-producing bacterium, strain KNHs209T, was isolated from a switchgrass microcosm seeded with forest soil. Cells were highly motile rods, often forming long filamentous chains which were easily observed moving under the microscope. Its closest phylogenetic relative was Eisenbergiella tayi (16S rRNA gene sequence identity 94.2 %), although it was easily distinguishable based on its morphology and physiology. Whole-genome sequencing enabled development of a minimal medium, and also suggested that the organism is capable of fixing nitrogen. Its wide variety of growth substrates was mirrored by a high number of encoded chemotaxis receptors (45, the highest in the family Lachnospiraceae ). Strain KNHs209T utilized a wide variety of carbohydrates, but not cellulose or xylan. Fermentation products included formate, acetate and butyrate; sulfur compounds and nitrate were not reduced. Strain KNHs209T grew optimally at 35–40 °C and pH 7. The genomic DNA G+C content was 42.74 mol%; the major membrane fatty acids were C14 : 0 and C16 : 0. Based on phenotypic, genomic, phylogenetic and chemotaxonomic analyses, this organism represents a novel genus and species within the family Lachnospiraceae for which the name Kineothrix alysoides, gen. nov., sp. nov. is proposed. The type strain is KNHs209T (=ATCC TSD-26T=DSM 100556T).

A Gram-stain-positive, aerobic, non-endospore-forming organism, isolated from a coolant lubricant solution was studied for its taxonomic position. On the basis of 16S rRNA gene sequence similarity comparisons, strain KSS-154-50T was grouped into the genus Cohnella , most closely related to Cohnella formosensis CC-ALFALFA-35T (97.3 % 16S rRNA gene sequence similarity), Cohnella rhizosphaerae CSE-5610T (97.1 %) and Cohnella nanjingensis D45T (97.0 %); the 16S rRNA gene sequence similarity to other species of the genus Cohnella was <97.0 %. The fatty acid profile from whole cell hydrolysates was very similar to those reported for other species of the genus Cohnella and supported the allocation to the genus Cohnella . In the fatty acid profiles, iso- and anteiso-branched fatty acids were found as major compounds. The quinone system consisted predominantly of menaquinone MK-7. The polar lipid profile contained the major lipids diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified phospholipid. The major polyamine is spermidine. The results of physiological and biochemical characterization allowed in addition a phenotypic differentiation of strain KSS-154-50T from the three most closely related species. Hence, strain KSS-154-50T represents a novel species of the genus Cohnella , for which the name Cohnella lubricantis sp. nov. is proposed. The type strain is KSS-154-50T (=LMG 29763T=CCM 8707T).

An aerobic, budding, dark pink to red-pigmented bacterium was isolated from an acidic boreal Sphagnum peat bog and designated strain SP5T. Cells of this strain were non-motile spheres that were uniformly covered with crateriform pits and fimbria, and tended to form aggregates during growth in liquid media. Strain SP5T was capable of growth between pH 4.0 and pH 6.8 (optimum at pH 5.5–6.0) and at temperatures between 10 and 30 °C (optimum at 20–25 °C). The preferred growth substrates were sugars and some heteropolysaccharides. The major fatty acids were C20 : 1 ω9c, C16 : 1 ω9c and C16 : 0, and the major polar lipid was trimethylornithine. Cells contained also significant amounts of bound (ω-1)OH-C30 : 1 fatty acid. The quinone was menaquinone-6, and the G+C content of the DNA was 60.7 mol%. Strain SP5T was a member of the order Planctomycetales and belonged to the phylogenetic lineage defined by the genus Gemmata . It displayed 88 and 89 % 16S rRNA gene sequence similarity to Gemmata obscuriglobusUQM 2246T and ‘ Gemmata massiliana’ IIL30, 89 % to Zavarzinella formosa A10T and 86 % to Telmatocola sphagniphila SP2T. However, strain SP5T differed from members of these genera by cell morphology, substrate utilization pattern and fatty acid composition. Based on these data, the novel isolate should be considered as representing a novel species of a new genus of planctomycetes, for which the name Fimbriiglobus ruber gen. nov., sp. nov, is proposed. The type strain is SP5T (=LMG 29572T=VKM B-3045T). We also suggest the establishment of a novel family, Gemmataceaefam. nov., which includes the phylogenetically related genera Gemmata , Zavarzinella , Telmatocola and Fimbriiglobus .

A novel phytoplasma subgroup strain SC-Phy385 (GenBank accession number HF586648) was found associated with Sugarcane Grassy Shoot (SCGS) disease in India. Sugarcane (Saccharum officinarum L.) leaf samples with ‘grassy shoot’ symptoms were collected from the western region of Maharashtra state. The analysis based on restriction fragment length polymorphism (RFLP) profiles and 16S rRNA gene sequences indicated that most of the phytoplasma strains belong to the 16SrXI-B group. However, SCGS phytoplasma strain SC-Phy385 showed unique RFLP profiles with a similarity coefficient of 0.87 using online interactive phytoplasma classification tool, iPhyClassifier. The actual and virtual RFLP profiles of SC-Phy385 using amplified products of the 16S rRNA partial gene and its multiple sequence alignment with other RYD group phytoplasma sequences revealed that this strain was different from phytoplasma groups described earlier, representing new subgroup 16SrXI-F. The 16S rRNA gene-based phylogenetic analysis of reported RYD and BGWL group phytoplasmas showed that they are a genetically diverse group of phytoplasmas.

A strictly anaerobic Gram-stain-negative bacterium, designated strain SEBR 4223T, was isolated from the production water of an offshore Congolese oil field. Cells were non-motile, pleomorphic and had spherical, annular or budding shapes, often exhibiting long stalks. Strain SEBR 4223T grew on a range of carbohydrates, optimally at 37 °C and pH 7, in a medium containing 40 g l−1 NaCl. Predominant fatty acids were C14 : 0, C14 : 0 DMA, C16 : 0 and C16 : 1ω7c and the major polar lipids were phosphoglycolipids, phospholipids, glycolipids and diphosphatidylglycerol. The G+C content of the DNA was 28.7 mol%. Phylogenetic analysis, based on the 16S rRNA gene sequence, showed that strain SEBR 4223T and Sphaerochaeta multiformis MO-SPC2T formed a cluster with similarity to other species of the genus Sphaerochaeta of of less than 86 %. On the basis of the phenotypic characteristics and taxonomic analyses, we propose a novel genus, Pleomorphochaeta gen. nov., to accommodate the novel species Pleomorphochaeta caudata sp. nov., with SEBR 4223T (=DSM 103077T=JCM 31 475T) as the type strain. We also propose the reclassification of Sphaerochaeta multiformis MO SPC2T as Pleomorphochaeta multiformis MO-SPC2T comb. nov., the type strain of this novel genus and emend description of the genus Sphaerochaeta .

The phylum Acidobacteria represents one of the highly diverse but poorly characterized phylogenetic groups of the domain Bacteria. The taxonomically described acidobacteria belong to 27 genera and 49 species, which represent subdivisions 1, 3, 4, 6, 8, 10 and 23 of this phylum. However, the corresponding family ranks have been defined only for some of these characterized micro-organisms. Here, we suggest the establishment of a novel family, Bryobacteraceae fam. nov., to accommodate taxonomically described members of subdivision 3 Acidobacteria . This family is characterized by Gram-stain-negative, non-spore-forming and non-motile rods, which divide by binary fission. Members of this family are mildly acidophilic, mesophilic, aerobic and facultatively anaerobic chemoheterotrophs that utilize various sugars and polysaccharides. The major fatty acids are iso-C15 : 0 and C16 : 1 ω7c; the cells also contain significant amounts of 13,16-dimethyloctacosanedioic (iso-diabolic) acid. Currently, the family comprises the genera Bryobacter and Paludibaculum .

A polyphasic approach was used to characterize a novel bacterium, designated strain TPP412T, isolated from a paddy soil in Taiwan. Strain TPP412T was Gram-stain-negative, facultatively anaerobic, rod-shaped, motile with a single polar flagellum and lacked bacteriochlorophyll. Growth was observed at 24–45 °C (optimal 25 °C), at pH 5.0–10.0 (optimal pH 7.0) and with 0–0.75 % (w/v) NaCl. Strain TPP412T showed highest 16S rRNA gene sequence similarity to members of the genera Rhodocyclus (94.1–94.5 %), Azospira (93.9–94.5 %) and Propionivibrio (93.4–94.4 %) and established a discrete taxonomic lineage in phylogenetic analysis. The major fatty acids found in strain TPP412T were C12 : 0, C12 : 0 3-OH, iso-C15 : 0 3-OH, C16 : 0, C16 : 1 ω7c/C16  : 1 ω6c and C18 : 1 ω7c/C18  : 1 ω6c. The major polar lipids consisted of phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylglycerol and an unidentified lipid. The polyamine pattern showed a predominance of putrescine and a minor amount of spermidine. The DNA G+C content was 58.4 mol% and the predominant quinone system was ubiquinone-8 (Q-8). The low 16S rRNA gene sequence similarity values (≤94.5%) and distinct phylogenetic clustering clearly distinguished strain TPP412T from other representatives of the family Rhodocyclaceae . Based on the discrete phylogenetic, phenotypic and chemotaxonomic traits together with results of comparative 16S rRNA gene sequence analysis, strain TPP412T is considered to represent a novel species of a new genus in the family Rhodocyclaceae , for which the name Oryzomicrobium terrae gen. nov., sp. nov. is proposed. The type strain of Oryzomicrobium terrae is TPP412T (=BCRC 80905T=JCM 30814T).

A strain of filamentous sulfur bacteria was isolated from freshwater spring contaminated with residential and agricultural wastewater in Moscow region, Russia. According to the results of phylogenetic analysis, strain D-402T belonged to the genus Beggiatoa within the family Beggiatoaceae of the class Gammaproteobacteria . Within the genus Beggiatoa , strain D-402T was most closely related to Beggiatoa alba strains. Strain D-402T had a DNA G+C content 42.1 mol%. The DNA-DNA hybridization value between strain D-402T and Beggiatoa alba strain B15LD was 33 %. Predominant fatty acids were C18 : 1 (46.1 and 53.3 %), C16 : 0 (15.5 and 16.2 %) and C16 : 1 (32.9 and 25.4 %) for strains D-402T and B15LD, respectively. In contrast to known representatives of Beggiatoa , strain D-402T was capable of chemolithoautotrophic growth with sulfide and thiosulfate as electron donors. Oxidation of sulfide and thiosulfate was accompanied by deposition of sulfur globules within the cells. Strain D-402T was capable of heterotrophic growth. The strain was capable of using different organic compounds, sulfur compounds and hydrogen as electron donors. Based on these observations, strain D-402T is considered as a representative of a species Beggiatoa leptomitoformis sp. nov. of the genus Beggiatoa . The type strain is D-402T (=DSM 14946T=UNIQEM U 779T).

Two Gram-stain-negative, aerobic, motile, halophilic, rod-shaped bacteria, designated Hb8T and Hb20, were isolated from a tidal flat environment located on the South-West Korean peninsula. The isolates grew at 10–37 °C, at pH 5.0–9.0 and in NaCl concentrations of 0.5–15 % (w/v; optimum, 3.0–6.0 %). Sequence analysis of the 16S rRNA indicated that the isolates belong to the genus Marinobacter and are most closely related to Marinobacter sediminum R65T (98.3 %), followed by Marinobacter lipolyticus SM19T, Marinobacter salsuginis SD-14BT and Marinobacter similis A3d10T. The overall 16S rRNA gene sequence similarity with these species was 97.9 %, but Hb8T and Hb20 showed 100 % sequence similarity with each other. DNA–DNA relatedness values of H8T and Hb20 suggested that these isolates represent a single species, while DNA–DNA relatedness values of the two novel isolates with M. sediminum DSM 27079T and M. similis DSM 15400T were only 21.3 and 22.9 %, respectively. The major fatty acids present in strain Hb8T were identified as C16 : 0, C16 : 1ω9c, C18 : 1ω9c, C18 : 0 3-OH and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c). Ubiquinone-9 was the main respiratory quinone in both the novel strains. The polar lipids found to be present included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, four unidentified phospholipids and five unidentified lipids. The genomic DNA G+C content of Hb8T and Hb20 was 54.5 mol%. Polyphasic analysis indicated that the two isolates are representatives of a novel species of the genus Marinobacte , for which the name Marinobacter salinus sp. nov. is proposed. The type strain is Hb8T (=KCTC 52255T=JCM 31416T).

A Gram-stain-negative, aerobic, motile, rod-shaped bacterium, designated 7M-Z19T, was isolated from a soil sample collected from a Pinus massoniana forest of Dinghushan Biosphere Reserve, Guangdong Province, PR China. Strain 7M-Z19T grew at pH 4.5–7.5 (optimum pH 6.0–6.5), 10 to 37 °C (optimum 28 °C) and NaCl concentration up to 2.0 % (optimum 0 %, w/v). iso-C17 : 0, C18 : 1 ω7c and C19 : 0 ω8c cyclo were the major fatty acids (>10 %) while ubiquinone-10 was the only respiratory quinone detected in 7M-Z19T. The polar lipids of the strain consisted of phosphatidylethanolamine, phosphatidyldimethylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, six unidentified aminophospholipids, three unidentified phospholipids, six unidentified lipids and a glycolipid. The DNA G+C content was 65.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate formed a distinct lineage with Dongia mobilis and Dongia rigui within the family Rhodospirillaceae , but with a low sequence similarity of 92.7 and 92.0 %, respectively. On the basis of phylogenetic, phenotypic, physiological and chemotaxonomic distinctiveness, strain 7M-Z19T should be placed in the family Rhodospirillaceae as a representative of a novel genus and species, for which the name Aliidongia dinghuensis gen. nov., sp. nov., is proposed. The type strain of the type species is 7M-Z19T (=NBRC 112240T=KCTC 52134T=CGMCC 1.15725T).

Strain JW12T, isolated from surface seawater of the Arabian Sea, was subjected to characterization by a polyphasic taxonomic approach. Cells of the isolate were Gram-stain-negative, aerobic and rod-shaped. It accumulated poly-β-hydroxybutyrate. On the basis of 16S rRNA gene sequence analysis, strain JW12T was closely related to Alteromonas confluentis , with 16S rRNA gene sequence similarity of 98.0 %. Phylogenetic analysis revealed that it fell within the cluster of the genus Alteromonas and represented one independent lineage with A. confluentis . The average nucleotide identity (ANI) value and the genome-to-genome distance between strain JW12T and A. confluentis KCTC 42603T were 70.0 and 21.3 %, respectively. The sole respiratory quinone was ubiquinone-8 (Q8). The principal fatty acids were summed feature 3 (C16 : 1 ω7c and/or iso-C15 : 0 2-OH), C16 : 0 and C18 : 1 ω7c. The major polar lipids included phosphatidylethanolamine, phosphatidylglycerol, two unidentified glycolipids and one aminophospholipid. The DNA G+C content was 48.4 mol%. Differential phylogenetic distinctiveness and chemotaxonomic differences, together with phenotypic properties obtained in this study, revealed that strain JW12T could be differentiated from the closely related species. Therefore, it is proposed that strain JW12T represents a novel species in the genus Alteromonas , for which the name Alteromonas lipolytica sp. nov. (type strain, JW12T=CGMCC 1.15735T=KCTC 52408T=MCCC 1K03175T), is proposed.

A novel, mesophilic, strictly anaerobic, sulfate-reducing and propionate-oxidizing bacterium, strain Prop6T, was enriched and isolated from a municipal anaerobic sewage sludge digester. Cells were Gram-stain-negative, catalase-positive, oval rods, motile by means of amphitrichous flagella, non-spore-forming and contained menaquinone MK-5(H2) as the major respiratory quinone. The genomic DNA G+C content was 51.7 mol%. The optimal NaCl concentration, temperature and pH were 2–5 g l−1, 35 °C and pH 7.6, respectively. Strain Prop6T could only oxidize propionate, lactate and pyruvate (weakly) with sulfate, sulfite or thiosulfate, mainly to acetate. Strain Prop6T fermented pyruvate and lactate to acetate and propionate. The predominant cellular fatty acids were C14 : 0, C16 : 0, C16 : 1ω7, C16 : 1ω5, C17 : 1ω6 and C18 : 1ω7. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the newly isolated strain was a member of the genus Desulfobulbus , with Desulfobulbus elongatus DSM 2908T, Desulfobulbus propionicus DSM 2032T and Desulfobulbus rhabdoformis DSM 8777T as closest relatives among species with validly published names. On the basis of genotypic, phenotypic and chemotaxonomic characteristics, it is proposed that the isolate represents a novel species, Desulfobulbus oligotrophicus sp. nov. The type strain is Prop6T (=DSM 103420T=JCM 31535T).

A novel Gram-stain-negative, non-spore-forming, facultatively anaerobic bacterium, designated YH6T, was isolated from marine sediment in Weihai, China. Cells of starin YH6T were motile, straight rods that formed ivory–white colonies on 2216E agar. Optimal growth occurred at 28–33 °C (range 15–37 °C), in the presence of 2–4 % (w/v) NaCl (range 1–8 %) and at pH 7.5–8.5 (range pH 6.5–9.0). The sole respiratory lipoquinone was Q-8, and the major fatty acids (>10 %) were C16 : 0 and summed feature 3 (C16 : 1 ω7c/iso-C15 : 0 2-OH). The polar lipids profile of the novel strain consisted of phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol and several other unknown lipids (phospholipids, lipid and phosphoaminolipid). The G+C content of the genomic DNA was 46.5 mol%. The closest type strain phylogenetically to strain YH6T was Vibrio variabilis (92.99 % 16S rRNA gene sequence similarity) followed by Paramoritella alkaliphila (92.55 %), Pseudoalteromonas aurantia (92.20 %) and Pseudoalteromonas citrea (92.20 %). Phylogenetic analysis of the 16S rRNA gene sequence placed the novel strain in the order Alteromonadales , class Gammaproteobacteria . On the basis of the 16S rRNA gene sequence data as well as physiological and biochemical characteristics, we concluded that strain YH6T represents a novel species of a new genus. We propose the name of Motilimonas eburnea gen. nov., sp. nov. for this novel species. The type strain of the novel species is YH6T (=KCTC 42594T=MCCC 1H00122T).

A bacterial strain designated Ca6T was isolated from polycyclic aromatic hydrocarbon (PAH)-contaminated soil from the site of a former manufactured gas plant in Charlotte, NC, USA, and linked phylogenetically to the family Rhodocyclaceae of the class Betaproteobacteria . Its 16S rRNA gene sequence was highly similar to globally distributed environmental sequences, including those previously designated ‘Pyrene Group 1’ demonstrated to grow on the PAHs phenanthrene and pyrene by stable-isotope probing. The most closely related described relative was Sulfuritalea hydrogenivorans strain sk43HT (93.6 % 16S rRNA gene sequence identity). In addition to a limited number of organic acids, Ca6T was capable of growth on the monoaromatic compounds benzene and toluene, and the azaarene carbazole, as sole sources of carbon and energy. Growth on the PAHs phenanthrene and pyrene was also confirmed. Optimal growth was observed aerobically under mesophilic temperature, neutral pH and low salinity conditions. Major fatty acids present included summed feature 3 (C16 : 1ω7c or C16 : 1ω6c) and C16 : 0. The DNA G+C content of the single chromosome was 55.14  mol% as determined by complete genome sequencing. Due to its distinct genetic and physiological properties, strain Ca6T is proposed as a member of a novel genus and species within the family Rhodocyclaceae , for which the name Rugosibacter aromaticivorans gen. nov., sp. nov. is proposed. The type strain of the species is Ca6T (=ATCC TSD-59T=DSM 103039T).

A Gram-stain-negative and strictly aerobic bacterium, designated strain SAG6T, was isolated from estuary sediment in South Korea. Cells of strain SAG6T were found to be oxidase- and catalase-positive rods with gliding motility. Cell growth was observed at 15–40 °C (optimum 30 °C), at pH 6.5–10.0 (optimum pH 7.0) and in the presence of 0.5–13.0 % (w/v) NaCl (optimum 2.0 %). Ubiquinone-10 was the only detected respiratory quinone and summed feature 8 (comprising C18 : 1ω7c/C18  : 1ω6c), C16 : 0, C18 : 1ω7c 11-methyl and C12 : 0 were the major fatty acids identified (>5 % of the total fatty acids). The polar lipids of strain SAG6T consisted of phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified aminolipid and two unidentified lipids. The G+C content of the genomic DNA was 66.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain SAG6T formed a tight phyletic lineage within the genus Roseovarius . Strain SAG6T was most closely related to Roseovarius indicus B108T with 97.6 % 16S rRNA gene sequence similarity. Based on phenotypic, chemotaxonomic and molecular features, strain SAG6T clearly represents a novel species of the genus Roseovarius , for which the name Roseovarius confluentis sp. nov. is proposed. The type strain is SAG6T (=KACC 18598T=JCM 31541T).