Roseomonas populi sp. nov., an acetate-degrading bacteria isolated from the stem of Populus tomentosa.

Strain CN29T, isolated from the stem of 5- to 6-year-old Populus tomentosa in Shandong, China, was characterized using a polyphasic taxonomic approach. Cells of CN29T were Gram-stain negative, aerobic, nonspore-forming, and nonmotile coccoid. Growth occurred at 20-37 °C, pH 4.0-9.0 (optimum, pH 6.0), and with 0-1% NaCl (optimum, 1%). Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain CN29T was closely related to members of the genus Roseomonas and closest to Roseomonas pecuniae N75T (96.6%). This classification was further supported by phylogenetic analysis using additional core genes. The average nucleotide identity and digital DNA‒DNA hybridization values between strain CN29T and Roseomonas populi CN29T were 82.7% and 27.8%, respectively. The genome size of strain CN29T was 5.87 Mb, with a G + C content of 70.9%. The major cellular fatty acids included summed feature 8 (C18:1 ω7c/C18:1 ω6c), C19:0 cyclo ω8c and C16:0. The major respiratory quinone was Q-10. The polar lipids were phosphatidylcholine, aminolipid, phosphatidylglycerol, and diphosphatidylglycerol. Strain CN29T can utilize acetate as a carbon source for growth and metabolism. Additionally, it contains acid phosphatase (2-naphthyl phosphate), which catalyzes the hydrolysis of phosphoric monoesters. The CN29T strain contains several genes, including maeB, gdhB, and cysJ, involved in carbon, nitrogen, and sulfur cycling. These findings suggest that the strain may actively participate in ecosystem cycling, leading to soil improvement and promoting the growth of poplar trees. Based on the phylogenetic, phenotypic, and genotypic characteristics, strain CN29T is concluded to represent a novel species of the genus Roseomonas, for which the name Roseomonas populi sp. nov. is proposed. The type strain is CN29T (= JCM 35579T = GDMCC 1.3267T).

Roseomonas ponticola sp. nov., a novel bacterium isolated from Pearl River estuary.

A novel species of the genus Roseomonas, designated SYSU M41301T, was isolated from water sample of the Pearl River estuary in Guangdong, China. Polyphasic, taxonomic and phylogenomic analyses were used to determine the taxonomy position of the strain. Phylogenetic analysis using 16S rRNA gene sequence indicated that strain SYSU M41301T showed the highest sequence similarity to Roseomonas stagni KCTC 22213T (97.9 %) and Roseomonas riguiloci KCTC 23339T (96.4 %). The novel species could be differentiated from other species of the genus Roseomonas by its distinct phenotypic and genotypic characteristics. The isolate was Gram-staining-negative, aerobic, short rod-shape, oxidase-positive and non-motile. The predominant respiratory quinone was ubiquinone 8 (Q-8). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, and one unidentified polar lipid. The major fatty acids (>10 % of total) were 11-methyl C18 : 1 ω7c, summed feature 3 (C16 : 1 ω7c and/ or C16 : 1 ω6c) and summed feature 8 (C18:  :1 ω7c and/or C18 : 1 ω6c). The G+C content of the novel isolate based on genomic DNA was 72.0 mol%. On the basis of phenotypic, genotypic and phylogenetic data, strain SYSU M41301T should be considered to represent a novel species in the genus Roseomonas, for which the name Roseomonas ponticola sp. nov. is proposed with the type strain SYSU M41301T (=KCTC 72726T=CGMCC 1.18613T).

Roseomonas oleicola sp. nov., isolated from an oil production mixture in Yumen Oilfield, and emended description of Roseomonas frigidaquae.

A pink, ovoid-shaped, Gram-stain-negative, strictly aerobic and motile bacterial strain, designated ROY-5-3T, was isolated from an oil production mixture from Yumen Oilfield in PR China. The strain grew at 4-42 °C (optimum, 30 °C), at pH 5-10 (optimum, 7) and with 0-5 % (w/v) NaCl (optimum, 0%). The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that ROY-5-3T belongs to the genus Roseomonas and shared the highest pairwise similarities with Roseomonas frigidaquae CW67T (98.1%), Roseomonas selenitidurans BU-1T (97.8%), Roseomonas tokyonensis K-20T (97.7%) and Roseomonas stagni HS-69T (97.3%). The average nucleotide identity and digital DNA-DNA hybridization values between ROY-5-3T and other related type strains of Roseomonas species were less than 84.08 and 28.60 %, respectively, both below the species delineation threshold. Pan-genomic analysis showed that the novel isolate ROY-5-3T shared 3265 core gene families with the four closely related type strains in Roseomonas, and the number of strain-specific gene families was 513. The major fatty acids were identified as summed feature 8 (C18 : 1 ω6c/C18 : 1 ω7c), summed feature 3 (C16 : 1 ω6c/C16 : 1 ω7c) and C16 : 0. Strain ROY-5-3T contained Q-10 as the main ubiquinone and the genomic DNA G+C content was 69.8 mol%. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and phosphatidylglycerol. Based on the phylogenetic, morphological, physiological, chemotaxonomic and genome analyses, strain ROY-5-3T represents a novel species of the genus Roseomonas for which the name Roseomonas oleicola sp. nov. is proposed. The type strain is ROY-5-3T (=CGMCC 1.13459T =KCTC 82484T).

Roseomonas harenae sp. nov., from desert gravel soil.

A Gram-stain-negative, aerobic, non-motile, pink-pigmented, coccus bacterium, designated CPCC 101081T, was isolated from a gravel soil sample collected from Badain Jara desert, PR China. Growth of the isolate occurred at 10-37 °C and pH 5.0-8.0, with optimal growth at 28-32 °C and pH 7.0, respectively. The major cellular fatty acids were summed feature 8 (C18:1ω7c/C 18:1ω6c), summed feature 3 (C 16:1ω6c/C16:1ω7c) and C18:12-OH. Q-10 was detected as the main respiratory quinone. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, an unidentified phospholipid, an amino-containing lipid and an unidentified glycophospholipid were examined in the polar lipids extraction. The 16S rRNA gene sequence comparison of strain CPCC 101081T with the available sequences in the GenBank database showed that the isolate was closely related to members of the genus Rosenomonas, with the highest similarity to Roseomonas rosea DSM 14916T (97.4 %). In the phylogenetic trees based on 16S rRNA gene sequences and the core genomes, strain CPCC 101081T was included within the clade of the genus Roseomonas, representing a species level, with the closest neighbor of R. rosea DSM 14916T . The genomic DNA G+C content was 68.7 mol%. The average nucleotide identity and the digital DNA-DNA hybridization values between strain CPCC 101081T and the related type strains of the genus Roseomonas were all far lower than the cut-off values for definition species. On the basis of above phenotypic and genotypic characteristics, strain CPCC 101081T is proposed to represent a novel species of the genus Roseomonas with the name Roseomonas harenae sp. nov. strain CPCC 101081T (=KCTC 62852T=NBRC 113512T) is the type strain of the species.

Roseomonas species infections in humans: a systematic review.

Roseomonas species have been recognized to cause infections in immunocompromised individuals. The purpose of this study was to systemically review all published cases of Roseomonas infections in humans and describe the epidemiology, microbiology, antimicrobial susceptibility, treatment and outcomes of these infections in humans. We performed a systematic review of PubMed (through 20th Octrober 2019) for studies providing epidemiological, clinical, microbiological as well as treatment data and outcomes of Roseomonas species infections. A total of 37 studies, containing data of 99 patients, were included in the analysis. The most common Roseomonas infections were those of the bloodstream in 74.7% (74 patients), musculoskeletal infections in 8.1% (8 patients), skin and soft tissue infections (SSTIs) and peritoneal dialysis-associated peritonitis in 6.1% (6 patients) each. Epidemiology of these infections differed, with bacteremias being more prevalent in patients with malignancy and central venous lines, musculoskeletal infections being more prevalent after orthopedic surgery, and SSTIs occurring without any reported underlying cause. Resistance to beta-lactams was very high with penicillin, piperacillin/tazobactam resistance and cephalosporin resistance at 96.6%, 90.7% and 77.8% respectively, while quinolone resistance was 9.1%. Quinolones, carbapenems and cephalosporins are the most common agents used for treatment, irrespectively of the infection site. Overall mortality was 3% (3 patients), with the mortality attributed to Roseomonas being at 1% (1 patient).

Roseomonas vastitatis sp. nov. isolated from Badain Jaran desert in China.

A Gram-stain-negative, non-motile, coccobacillus-shaped bacterium, designated CPCC 101021T, was isolated from a sandy soil sample collected from Badain Jaran desert, China. Its 16S rRNA gene sequence was closely related to those of members of the genus Roseomonas, showing high similarities with Roseomonas hibiscisoli THG-N2.22T (98.0 %), Roseomonas oryzae KCTC 42542T (97.9 %), Roseomonas rhizosphaerae YW11T (97.9 %) and Roseomonas suffusca S1T (97.8 %). In the phylogenetic tree based on 16S rRNA gene sequences, strain CPCC 101021T formed a distinct subclade with R. oryzae KCTC 42542T within the genus Roseomonas. Growth of the isolate occurred at 15-37 °C and pH 6.0-8.5, with optimal growth at 30 °C and pH 7.0. The major cellular fatty acids were C18 : 1ω7c, summed feature 8 (C16 : 1ω7c/C16 : 1ω6c), summed feature 3 (C16 : 1ω6c/C16 : 1ω7c) and C16 : 0ω6c. Q-10 was detected as the main component in the respiratory quinone system, with Q-9 as a minor component. Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, an unidentified phospholipid, an unidentified aminolipid and an unidentified glycolipid were found in the polar lipid profile. The genomic DNA G+C content was 68.7 mol%. The average nucleotide identity was 84.6 % when comparing the draft genome sequences of strain CPCC 101021T with R. oryzae KCTC 42542T. On the basis of genotypic, chemotaxonomic and phenotypic characteristics, strain CPCC 101021T is proposed to represent a novel species of the genus Roseomonas with the name Roseomonas vastitatis sp. nov. Strain CPCC 101021T (=J1A743T=KCTC 62043T) is the type strain of the species.

Microvirga rosea sp. nov.: a nanoparticle producing bacterium isolated from soil of rose garden.

A Gram-stain negative, aerobic, non-motile, and rod-shaped novel bacterial strain, designated MAH-2T, was isolated from a soil sample of rose garden and was characterized using a polyphasic approach. The colonies were light pink color, smooth, circular and 0.2-0.6 mm in diameter when grown on nutrient agar for 3 days. Strain MAH-2T grows at 15-40 °C (optimum growth temperature 30 °C), at pH 5.0-7.0 (optimum growth pH 6.5) and at 0-2% NaCl (optimum 0-0.5%). Cell growth occurs on nutrient agar and R2A agar but not on tryptone soya agar, luria-bertani agar and MacConkey agar. The strain was positive for both catalase and oxidase tests. The strain was able to synthesis of silver nanoparticles. According to the 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Microvirga and was most closely related to Microvirga soli R491T (96.7% sequence similarity), Microvirga subterranea Fail4T (96.4%), Microvirga guangxiensis 25BT (96.0%) and Microvirga aerophila 5420S-12T (95.9%). The genomic DNA G + C content of isolated strain was determined to be 62.5 mol% and the predominant isoprenoid quinone was Q-10. The major fatty acids were identified as summed feature 8 (comprising C18:1 ω7c and/or C18:1 ω6c) and C19:0 cyclo ω8c. On the basis of these phenotypic, genotypic, and chemotaxonomic studies and DNA-DNA hybridization results, the isolated strain MAH-2T represents a novel species, for which the name Microvirga rosea sp. nov. is proposed, with MAH-2T as the type strain (= KACC 19290T = CGMCC1.16488T).

Roseomonas radiodurans sp. nov., a gamma-radiation-resistant bacterium isolated from gamma ray-irradiated soil.

A bacterial strain, designated 17Sr1-1T, was isolated from gamma ray-irradiated soil. Cells of this strain were Gram-stain-negative, strictly aerobic, motile and non-spore-forming rods. Growth occurred at 18-42 ˚C and pH 6.0-8.0, but no growth occurred at 2 % NaCl concentration. The major fatty acids of strain 17Sr1-1T were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), iso-C17 : 1ω5c and C16 : 0. The polar lipid profile contained diphosphatidylglycerol, glycolipid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and four unidentified lipids. The G+C content of the genomic DNA of 17Sr1-1T was 71.9 mol%. The 16S rRNA gene sequence analysis showed that strain 17Sr1-1T was phylogenetically related to Roseomonas pecuniae N75T and Roseomonas rosea 173-96T (96.6 and 96.3 % sequence similarity, respectively). The genotypic and phenotypic data showed that strain 17Sr1-1T could be distinguished from its phylogenetically related species, and that this strain represented a novel species within the genus Roseomonas, for which the name Roseomonas radiodurans sp. nov. (type strain 17Sr1-1T=KCTC 52899T=NBRC 112872T) is proposed as the first reported gamma ray-resistant Roseomonas species.

Roseomonas deserti sp. nov., isolated from crude oil contaminated desert sand.

Two dark pink pigmented bacterial strains (M3T and M11) were isolated from crude oil contaminated desert sand from Kuwait. Both strains were Gram-stain-negative and small-rod to oval-shaped bacteria. Strains M3T and M11 grew at 13-42 °C (optimum, 30-35 °C) and pH 6.5-9.0 (optimum, 7.0-7.5). No additional NaCl was required for the growth of both strains. The genomic DNA G+C content of strains M3T and M11 were 69.5 and 69.0 mol%, respectively. Both strains were closely related and the mean DNA-DNA hybridization value was 92±1 %. 16S rRNA gene sequence comparisons of both strains indicated that they belong to the genus Roseomonas. Strains M3T and M11 had a sequence similarity of 97.3 and 97.4 % with Roseomonas oryzae JC288T, respectively. Both strains had <97 % 16S rRNA gene sequence similarity with other members of the genus Roseomonas. Strain M3T showed 18±2 and 13±2 % reassociation (based on DNA-DNA hybridization) with R. oryzae KCTC 42542T and Roseomonas cervicalis KACC 11686T, respectively. The major cellular fatty acids (>5 %) were identified as C18 : 1ω6c/C18 : 1ω7c, C16 : 1ω6c/C16 : 1ω7c and C16 : 0 in both strains. Both strains showed diphosphatidylglycerol, phosphatidylglycerol, phosphatidyl-ethanolamine, phosphatidylcholine and unidentified glycolipid as major polar lipids. Based on distinct phenotypic, genotypic and phylogenetic differences from the previously described taxa, we propose the classification of strains M3T and M11 as representative of a novel species in the genus Roseomonas, for which the name Roseomonas deserti sp. nov. is suggested. The type strain is M3T (=KEMB 2255-459T=JCM 31275T).

Roseomonas aeriglobus sp. nov., isolated from an air-conditioning system.

A novel pale pink-coloured, strictly aerobic, Gram-stain negative bacterial strain, designated strain KER25-12T, was isolated from a laboratory air-conditioning system in South Korea. Cells were observed to be non-motile cocci showing positive catalase and oxidase reactions. Strain KER25-12T was found to grow at 10-30 °C (optimum, 25-30 °C), at pH 4.0-9.0 (optimum, pH 6.0-7.0) and in the presence of 0-2% (w/v) NaCl (optimum, 0%). Ubiquinone-10 and spermidine were detected as the sole respiratory quinone and the predominant polyamine, respectively. The major fatty acids were identified as summed feature 8 (comprising C18:1 ω7c and/or C18:1 ω6c), summed feature 3 (comprising C16:1 ω7c and/or C16:1 ω6c), C16:0 and C18:0. The genomic DNA G+C content of strain KER25-12T was determined to be 70.0 mol%. The major polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unidentified aminolipid. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that strain KER25-12T belongs to the genus Roseomonas and shows high sequence similarity to Roseomonas aerilata 5420S-30T (98.57%), Roseomonas pecuniae N75T (97.44%) and Roseomonas vinacea CPCC 100056T (97.40%). Based on the morphological, physiological, chemotaxonomic and phylogenetic features, strain KER25-12T is concluded to represent a novel species of the genus Roseomonas, for which the name Roseomonas aeriglobus sp. nov. is proposed. The type strain is KER25-12T (= KACC 19282T = JCM 32049T).

Roseomonas terricola sp. nov., isolated from agricultural soil.

A novel strain, designated EM302T, was isolated from a soil sample collected from farmland located in Yesan-gun in the Republic of Korea. The cells were Gram-stain-negative, aerobic, non-motile without flagella and coccobacilli-shaped. Colonies were circular with entire edges, convex, opaque and pink. The strain grew at 15-40 ˚C (optimum, 35 ˚C) and pH 6.0-9.0 (optimum, 7.0). The strain grew in R2A medium without the addition of NaCl. Based on 16S rRNA gene sequences analysis, strain EM302T was found to be phylogenetically related to Roseomonas wooponensis WW53T (96.5 % 16S rRNA gene sequence similarity), Roseomonas arcticisoli MC 3624T (95.2 %), Roseomonas aerilata 5420-30T (94.5 %), Roseomonas pecuniae N75T (94.4 %) and Roseomonas vinacea CPCC 100056T (94.4 %). The major cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and C16 : 0. The predominant respiratory quinone was Q-10. The major polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and an unidentified aminolipid. The DNA G+C content of the type strain was 65.7 mol%. On the basis of data presented here, strain EM302T is considered to represent a novel species of the genus Roseomonas, for which the name Roseomonasterricola sp. nov. is proposed. The type strain is EM302T (=KACC 13942T=KCTC 42906T=NBRC 111477T).

Roseomonas nepalensis sp. nov., isolated from oil-contaminated soil.

A wine-red-coloured, Gram-stain-negative, aerobic, non-motile and coccus-shaped bacterium, designated strain G-3-5T, was isolated from oil-contaminated soil of Biratnagar, Morang, Nepal, during a study of oil-utilizing bacteria. This strain was catalase-negative and oxidase-positive. It was able to grow at 10-37 °C, at pH 6.0-10.0 and with 0.02-1.02 % (w/v) NaCl. This strain was taxonomically characterized by a polyphasic approach. Based on 16S rRNA gene sequence analysis, strain G-3-5T belongs to the genus Roseomonas and is closely related to Roseomonas vinacea CPCC 100056T (97.81 % sequence similarity), Roseomonas aerilata 5420S-30T (96.68 %), Roseomonas pecuniae N75T (96.15 %), 'Roseomonas aceris' R-1 (95.75 %) and Roseomonas rosea 173/96T (95.30 %). The only respiratory quinone was ubiquinone-10. The polar lipid profile revealed the presence of phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine. The major fatty acids of strain G-3-5T were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0, C18 : 0 and C18 : 1 2-OH. The genomic DNA G+C content of this novel strain was 68.3 mol%. The DNA-DNA relatedness between strain G-3-5T and Roseomonas. vinacea KACC 13934T was 26.3 %. The morphological, physiological, chemotaxonomic and phylogenetic analyses clearly distinguished this strain from its closest phylogenetic neighbours. Thus, strain G-3-5T represents a novel species of the genus Roseomonas, for which the name Roseomonas nepalensis sp. nov. is proposed. The type strain is G-3-5T (=KEMB 9005-416T=KACC 18908T=JCM 31470T).

Skin microbiota is the main reservoir of Roseomonas mucosa, an emerging opportunistic pathogen so far assumed to be environmental.

Roseomonas spp. are increasingly involved in human infectious diseases. The environmental source for infection is generally admitted in published cases owing to the origin of most Roseomonas species and to their affiliation to the family Acetobacteraceae in Rhodospirillales, which mainly groups environmental bacteria. For a better delineation of Roseomonas habitat and infectious reservoir, we related phenotype, phylotype (16S rRNA gene), genomotype (pulsed-field gel electrophoresis) and origin of 33 strains isolated from humans, hospital environment and natural environment. Genetic and metagenomic databases were also surveyed. The population structure of the genus showed clades associated with humans, whereas others grouped environmental strains only. Roseomonas mucosa is the main human-associated species and the study supported the idea that opportunistic infections due to this species are related to the patient skin microbiota rather than to the environment. In contrast, some strains belonging to other species isolated from patients with cystic fibrosis were related to environmental clades, suggesting an exogenous source for patient colonization. Accurate knowledge about the reservoirs of opportunistic pathogens that have long been considered of environmental origin is still needed and would be helpful to improve infection control and epidemiological survey of emerging human pathogens.

Microvirga makkahensis sp. nov., and Microvirga arabica sp. nov., isolated from sandy arid soil.

The taxonomic positions of two Gram-negative strains, SV1470(T) and SV2184P(T), isolated from arid soil samples, were determined using a polyphasic approach. Analysis of the 16S rRNA gene and the concatenated sequences of three housekeeping gene loci (dnaK, rpoB and gyrB) confirmed that the strains belong to the genus Microvirga. Strain SV1470(T) was found to be closely related to Microvirga vignae BR3299(T) (98.8 %), Microvirga flocculans TFB(T) (98.3 %) and Microvirga lupini Lut6(T) (98.2 %), whilst similarity to other type strains of the genus ranged from 97.8 to 96.3 %; strain SV2184P(T) was found to be closely related to Microvirga aerilata 5420S-16(T) (98.0 %), Microvirga zambiensis WSM3693(T) (97.8 %) and M. flocculans ATCC BAA-817(T) (97.4 %), whilst similarity to other type strains of the genus ranged from 97.2 to 95.9 %. The G + C content of the genomic DNA was determined to be 61.5 mol % for strain SV1470(T) and 62.1 mol % for strain SV2184P(T). Both strains were found to have the same quinone system, with Q-10 as the major ubiquinone. The polar lipid profile of strain SV1470(T) was found to consist of phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified phospholipid and one unidentified aminolipid, while that of strain SV2184P(T) consisted of phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmethylethanolamine, one unidentified aminolipid, one unidentified aminophospholipid and two unidentified phospholipids. DNA-DNA relatedness studies showed that the two strains belong to different genomic species. The strains were also distinguished using a combination of phenotypic properties. Based on the genotypic and phenotypic data, the novel species Microvirga makkahensis sp. nov. (type strain SV1470(T) = DSM 25394(T) = KCTC 23863(T) = NRRL-B 24875(T)) and Microvirga arabica sp. nov. (type strain SV2184P(T) = DSM 25393(T) = KCTC 23864(T) = NRRL-B 24874(T)) are proposed.

Roseomonas oryzicola sp. nov., isolated from the rhizosphere of rice (Oryza sativa L.).

A Gram-stain-negative, coccobacilli-shaped bacterium, designated YC6724T, was isolated from the rhizosphere of rice in Jinju, Korea. The taxonomy of strain YC6724T was studied using a polyphasic approach. Strain YC6724T grew optimally at 30 °C and pH 7.0-8.0. Comparative 16S rRNA gene sequence analyses showed that the strain was most closely related to Roseomonas soli 5N26T (98.4 % 16S rRNA gene sequence similarity), Roseomonas lacus THG33T(97.3 %) and Roseomonas terrae DS-48T (97.3 %). Sequence similarities with other species of the genus Roseomonas with validly published names were lower than 94.0 %. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain YC6724T formed a distinct phyletic lineage within the genus Roseomonas. Strain YC6724T had DNA-DNA relatedness values of 16.6 %, 44.0 % and 33.2 % with R. soli KACC 16376T, R. terrae KACC 12677T and R. lacus KACC 11678T, respectively. The predominant fatty acids of strain YC6724T were C18 : 1ω7c and/or C18 : 1ω6c, C16 : 0 and C18 : 1 2-OH. The polar lipid profile contained phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol,diphosphatidylglycerol, an unknown aminolipid and two unknown lipids. The G+C content of the genomic DNA was 70.5 mol% and the major quinone was Q-10. Strain YC6724T contained spermidine as the major polyamine. On the basis of phenotypic, chemotaxonomic and molecular data, it is clear that strain YC6724T represents a novel species of the genus Roseomonas, for which the name Roseomonas oryzicola sp. nov. is proposed. The type strain is YC6724T (=KCTC 22478T=NBRC 109439T).

Roseomonas wooponensis sp. nov., isolated from wetland freshwater.

A non-motile, cocobacilli-shaped and pink-pigmented bacterium, designated strain WW53T, was isolated from wetland freshwater (Woopo wetland, Republic of Korea). Cells were Gram-stain-negative, catalase- and oxidase-positive. The major fatty acids were C18 : 1ω7c/C18 : 1ω6c and C16 : 0.The predominant quinone and polyamine were ubiquinone 10 (Q-10) and spermidine, respectively. The DNA G+C content was 71 mol%. The major polar lipids were phosphatidylethanolamine, phosphatidylcholine and an unknown aminolipid. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain WW53T belongs to the family Acetobacteraceae, and is related to the genus Roseomonas. Strain WW53T was most closely related to Roseomonas stagni HS-69T (95.3 % 16S rRNA gene sequence similarity). Results of a polyphasic taxonomy study suggested that the isolate represents a novel species in the genus Roseomonas, for which the name Roseomonas wooponensis sp. nov. is proposed. The type strain is WW53T ( = KCTC 32534T = JCM 19527T).

[Detection of methane in the water column at gas and oil seep sites in central and southern Lake Baikal].

Microbiological and biogeochemical investigation of the water column of oligotrophic Lake Baikal at the sites of the K2 and Bolshoy mud volcanoes and the Gorevoy Utes oil seep was carried out in July 2013. Total microbial numbers (TMN), cell numbers of type I and type II methanotrophs, and methane concentrations were measured; the rate of methane oxidation was determined. Methane concentrations in Lake Baikal water column varied from 0.09 to 1 µL/L, while methane oxidation rates varied from 0.007 to 0.9 nL/(L day). The highest rates of methane oxidation were revealed in the near-bottom water horizons at the sites of the Bolshoy mud volcano and the Gorevoy Utes oil seep. These were the sites where the most pronounced anomalies in methane concentration were also detected. TMN varied from 0.123 x 10(6) to 1.64 x 10(6) cells/mL. Methanotrophic bacteria were revealed in the water column at all sites, their abundance did not always correlate with methane concentrationsand the rates of methane oxidation. Methanotrophs constituted not more than 1.63% of the total microbial number, with their highest abundance in the upper 200 m of the water column.

Psychroglaciecola arctica gen. nov., sp. nov., isolated from Arctic glacial foreland soil.

A novel pink-pigmented, facultatively methylotrophic strain, designated M6-76T, was isolated from glacial foreland soil near Ny-Ålesund, Svalbard Archipelago, Norway. Cells of strain M6-76T were rod-shaped (0.4-0.7×0.8-2.0 µm), Gram-stain-negative, aerobic and motile by a single polar flagellum. Growth occurred at 4-28 °C (optimum 18 °C) and at pH 5-8 (optimum pH 7). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain M6-76T belonged to the family Methylobacteriaceae. The 16S rRNA gene sequence of the novel strain showed 94.6%, 94.0% and 93.9% sequence similarity to those of Methylobacterium salsuginis MRT, Methylobacterium organophilum ATCC 27886T and Microvirga subterranea FaiI4T, respectively. Cells could utilize methanol as the sole source of carbon and energy but not formate. The major respiratory quinone was Q-10. The polar lipids were phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine and two unknown polar lipids. The predominant cellular fatty acids were summed feature 8 (C18:1ω7c and/or C18:1ω6c), summed feature 3 (C16:1ω6c and/or C16:1ω7c) and C16:0. The DNA G+C content was 67 mol%. The polyphasic data presented in this study indicated that the isolate should be classified as representing a novel species of a new genus within the family Methylobacteriaceae. The name Psychroglaciecola arctica gen. nov., sp. nov. is therefore proposed for the isolate. The type strain of the type species is M6-76T (=CCTCC AB 2013033T=KACC 17684T).

Roseomonas sediminicola sp. nov., isolated from fresh water.

A Gram-stain negative, strictly aerobic, non-motile, non-spore-forming, and rod-shaped bacterial strain designated FW-3(T) was isolated from fresh water and its taxonomic position was investigated by using a polyphasic approach. Strain FW-3(T) was found to grow at 10-37 °C and at pH 7.0 in the absence of NaCl on nutrient agar. On the basis of 16S rRNA gene sequence similarity, strain FW-3(T) was shown to belong to the family Acetobacteraceae and to be related to Roseomonas lacus TH-G33(T) (97.2 % sequence similarity) and Roseomonas terrae DS-48(T) (96.4 %). The G+C content of the genomic DNA was determined to be 68.0 %. The major menaquinone was determined to be Q-10 and the major fatty acids were identified as summed feature 7 (comprising C18:1 ω9c/ω12t/ω7c as defined by the MIDI system; 55.4 %), and C18:1 2OH (29.8 %). DNA and chemotaxonomic data supported the affiliation of strain FW-3(T) to the genus Roseomonas. Strain FW-3(T) could be differentiated genotypically and phenotypically from the recognized species of the genus Roseomonas. The novel isolate therefore represents a novel species, for which the name Roseomonas sediminicola sp. nov. is proposed, with the type strain FW-3(T) (=KACC 16616(T) = JCM 18210(T)).

Roseomonas riguiloci sp. nov., isolated from wetland freshwater.

A non-motile, coccobacillus-shaped and pink pigmented bacterium, designated strain 03SU10-P(T), was isolated from wetland freshwater (Woopo wetland, Republic of Korea). Cells were Gram reaction-negative and catalase- and oxidase-positive. The major fatty acids (>10% of total) were C(18:1)ω7c and summed feature 3 (iso-C(15:0) 2-OH and/or C(16:1)ω7c). The predominant respiratory lipoquinone was Q-10. The DNA G+C content was 68 mol%. The major polar lipids were phosphatidylethanolamine, phosphatidylcholine and an unknown aminolipid. Spermidine, putrescine and 1,3-diaminopropane were the major polyamines. A phylogenetic tree based on 16S rRNA gene sequence comparisons showed that strain 03SU10-P(T) formed an evolutionary lineage within the radiation enclosing the members of the genus Roseomonas. The nearest neighbour to the novel strain was Roseomonas stagni HS-69(T) (96.3% gene sequence similarity). The evidence provided by the polyphasic taxonomic approach used in this study indicated that strain 03SU10-P(T) could not be assigned to any recognized species; therefore a novel species is proposed, Roseomonas riguiloci sp. nov., with 03SU10-P(T) ( = KCTC 23339(T) = JCM 17520(T)) as the type strain.