- Volume 62, Issue 1, 2012

Phylogenetic positions, and genotypic and phenotypic characteristics of three novel methylotrophic isolates, strains 301T, 30S and SIP3-4, from sediment of Lake Washington, Seattle, USA, are described. The strains were restricted facultative methylotrophs capable of growth on single carbon compounds (methylamine and methanol) in addition to a limited range of multicarbon compounds. All strains used the N-methylglutamate pathway for methylamine oxidation. Strain SIP3-4 possessed the canonical (MxaFI) methanol dehydrogenase, but strains 301T and 30S did not. All three strains used the ribulose monophosphate pathway for C1 assimilation. The major fatty acids in the three strains were C16 : 0 and C16 : 1ω7c. The DNA G+C contents of strains 301T and SIP3-4 were 42.6 and 54.6 mol%, respectively. Based on 16S rRNA gene sequence phylogeny and the relevant phenotypic characteristics, strain SIP3-4 was assigned to the previously defined species Methylovorus glucosotrophus. Strains 301T and 30S were closely related to each other (100 % 16S rRNA gene sequence similarity) and shared 96.6 % 16S rRNA gene sequence similarity with a previously described isolate, Methylotenera mobilis JLW8T. Based on significant genomic and phenotypic divergence with the latter, strains 301T and 30S represent a novel species within the genus Methylotenera, for which the name Methylotenera versatilis sp. nov. is proposed; the type strain is 301T ( = VKM B-2679T = JCM 17579T). An emended description of the genus Methylotenera is provided.

A Gram-negative, motile, rod-shaped bacterial strain, HP15T, was isolated from aggregates taken from surface waters of the German Wadden Sea (German Bight). Of 82 marine isolates, HP15T was chosen for further study because of its high potential to induce production of transparent exopolymeric particles and aggregate formation while interacting with the diatom Thalassiosira weissflogii. HP15T grew optimally at 34–38 °C and pH 7.0–8.5, and was able to tolerate salt concentrations of 0.5–20 % (w/v) NaCl. HP15T was characterized chemotaxonomically by possessing ubiquinone-9 as the major respiratory lipoquinone, as well as C16 : 0, C18 : 1ω9c and C16 : 1ω7c/iso-C15 : 0 2-OH as the predominant fatty acids. The DNA G+C content of strain HP15T was 56.9 mol%. The closest relative based on 16S rRNA gene sequence analysis was the type strain of Marinobacter flavimaris, with 99 % similarity. Whole-genome relatedness values of HP15T to the type strains of M. flavimaris, Marinobacter salsuginis, Marinobacter lipolyticus and Marinobacter algicola were less than 70 %, as determined by DNA–DNA hybridization. On the basis of phenotypic and chemotaxonomic properties as well as phylogenetic analyses, the isolate represents a novel species, Marinobacter adhaerens sp. nov.; the type strain is HP15T ( = DSM 23420T = CIP 110141T).

A Gram-negative, heterotrophic, aerobic, marine bacterium, designated AIT1T, was isolated from a seawater sample collected in the shallow coastal region of Bitou Harbour, New Taipei City, Taiwan. Cells grown in broth cultures were straight or slightly curved rods that were motile by means of a single polar flagellum. Strain AIT1T required NaCl for growth, grew optimally at 30–40 °C and with 1.5–5.0 % NaCl, and was incapable of anaerobic growth by fermentation of glucose or other carbohydrates. The isoprenoid quinones consisted of Q-8 (95.2 %) and Q-9 (4.8 %). The major polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The cellular fatty acids were predominantly iso-branched and included iso-C17 : 0 (26.5 %), summed feature 9 (comprising iso-C17 : 1ω9c and/or 10-methyl C16 : 0; 25.9 %) and iso-C15 : 0 (20.5 %). The DNA G+C content was 51.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain AIT1T formed a distinct lineage within the class Gammaproteobacteria and was most closely related to members of the genus Idiomarina in the family Idiomarinaceae (91.5–93.9 % 16S rRNA gene sequence similarity). The phylogenetic data, together with chemotaxonomic, physiological and morphological data, revealed that the isolate should be classified as a representative of a novel species in a new genus in the family Idiomarinaceae, for which the name Aliidiomarina taiwanensis gen. nov., sp. nov. is proposed. The type strain is AIT1T ( = JCM 16052T = BCRC 80035T = NCCB 100321T).

A pink, aerobic, facultatively methylotrophic, motile, Gram-negative rod, designated Gh-105T, was isolated from the phyllosphere of cotton from Coimbatore (Tamilnadu, India). 16S rRNA gene sequence analysis showed clearly that the isolate belonged to the Methylobacterium cluster. Strain Gh-105T was most closely related to Methylobacterium adhaesivum AR27T (99 % 16S rRNA gene sequence similarity) and Methylobacterium iners 5317S-33T (97.5 %). The isolate grew with C1 compounds such as methanol and dichloromethane, but not with formaldehyde, formate, methylamine, trimethylamine or methane, as sole carbon sources and carried mxaF, which encodes methanol dehydrogenase and supports methylotrophic metabolism. The major fatty acid was C18 : 1ω7c and the G+C content of the genomic DNA was 64.2 mol%. Physiological and biochemical data and DNA–DNA relatedness with M. adhaesivum KACC 12195T and M. iners KACC 11765T revealed clear phenotypic and genotypic differences. For this reason, we propose that strain Gh-105T ( = CCM 7572T  = NRRL B-51692T) represents the type strain of a novel species, with the name Methylobacterium gossipiicola sp. nov.

Two restricted facultatively methylotrophic strains, designed BT and P, were isolated from rice roots. The isolates were strictly aerobic, Gram-negative, asporogenous, mesophilic, neutrophilic, motile rods that multiplied by binary fission and were able to synthesize indole-3-acetate. The cellular fatty acid profiles of the two strains were dominated by C16 : 0, C16 : 1ω7c and C16 : 0 2-OH. The major ubiquinone was Q-8. The predominant phospholipids were phosphatidylethanolamine and phosphatidylglycerol. Cardiolipin (diphosphatidylglycerol) was absent. The two strains assimilated methanol carbon at the level of formaldehyde via the ribulose monophosphate cycle (2-keto-3-deoxy-6-phosphogluconate variant). They lacked α-ketoglutarate dehydrogenase and glutamate dehydrogenase. They assimilated ammonium via the glutamate cycle enzymes glutamine synthetase and glutamate synthase. The DNA G+C contents of strains BT and P were 52.5 and 51.5 mol% (T m), respectively. The level of DNA–DNA reassociation between these strains was 78 %, indicating that they belong to one species. Phylogenetic analysis of strain BT based on 16S rRNA and methanol dehydrogenase (mxaF) gene sequences showed a high level of similarity to members of the genus Methylophilus. As the two isolates were clearly distinct from all recognized members of the genus Methylophilus based on phenotypic data and levels of DNA–DNA relatedness (30–46 %), they are considered to represent a novel species, for which the name Methylophilus glucosoxydans sp. nov. is proposed; the type strain is BT ( = VKM B-1607T = CCUG 59685T = DSM 5898T).

Three genera in the Rubiaceae (Pavetta, Psychotria and Sericanthe) harbour bacterial endosymbionts within leaf nodules or galls. The present paper identifies the bacterial endophytes in three leaf-nodulating Pavetta species. In order to reveal their identity and assess their phylogenetic position, 16S rRNA, recA and gyrB genes were sequenced from an extensive sampling of Burkholderia strains. This multigene approach results in a robust phylogeny, which places the bacterial endosymbionts of Pavetta at two distinct positions within the genus Burkholderia (class Betaproteobacteria), suggesting that leaf-nodulating endosymbionts within Pavetta have different origins. The endophytes of nodulated Psychotria species were recognized as the closest relatives to the Pavetta endosymbionts. Our results suggest that the endosymbionts of Pavetta represent novel species, which can be classified as ‘Candidatus Burkholderia hispidae’, ‘Candidatus Burkholderia rigidae’ and ‘Candidatus Burkholderia schumannianae’.

A novel Gram-negative, non-motile bacterium, designated ZXM137T, was isolated from seawater collected from a coastal region of Qingdao, China, during a massive green algae (Enteromorpha prolifera) bloom. Strain ZXM137T was strictly aerobic and did not accumulate poly-β-hydroxybutyrate. Growth occurred with 0.5–11.0 % (w/v) NaCl, at pH 6–9 (optimum of pH 7) and at 4–45 °C (optimum at 28 °C). It contained Q-10 as the predominant ubiquinone and the major polar lipids were phosphatidylglycerol, phospholipids, and an unidentified aminolipid and lipid. The major cellular fatty acids of strain ZXM137T were C18 : 1ω7c, C18 : 1ω6c and 11-methyl C18 : 1ω7c. The DNA G+C content was 60.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain ZXM137T formed a distinct evolutionary lineage within the Roseobacter group in the class Alphaproteobacteria. On the basis of phenotypic, chemotaxonomic and phylogenetic evidence, strain ZXM137T represents a novel species in a new genus, for which the name Huaishuia halophila gen. nov., sp. nov. is proposed; the type strain is ZXM137T ( = CGMCC 1.8891T = LMG 24854T).

A Gram-negative, rod-shaped, non-motile, strictly aerobic bacterium, strain S3-63T, was isolated from desert sand of Xinjiang, China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain S3-63T had highest similarity to type strains of the genus Altererythrobacter, i.e. Altererythrobacter marinus H32T (97.2 % similarity), Altererythrobacter marensis MSW-14T (95.9 %), Altererythrobacter aestuarii KCTC 22735T (95.5 %), Altererythrobacter epoxidivorans JCS350T (95.1 %), Altererythrobacter namhicola KCTC 22736T (95.1 %), Altererythrobacter luteolus SW-109T (95.0 %) and Altererythrobacter indicus LMG 23789T (93.5 %). Growth occurred at 20–37 °C (optimum 30 °C), at pH 7.0–9.0 (optimum pH 8.0) and in 0–3 % (w/v) NaCl (optimum 1 %). The major respiratory quinone was ubiquinone-10 and the predominant cellular fatty acids were C18 : 1ω7c (50.8 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 12.6 %), C16 : 0 (12.3 %), C14 : 0 2-OH (7.3 %) and C17 : 1ω6c (4.5 %). The DNA G+C content was 64.6 mol%. Therefore, the phylogenetic, physiological and chemotaxonomic data demonstrated that strain S3-63T represents a novel species of the genus Altererythrobacter, for which the name Altererythrobacter xinjiangensis sp. nov. is proposed; the type strain is S3-63T ( = CCTCC AB 207166T = CIP 110125T). An emended description of the genus Altererythrobacter is provided.

A psychrotolerant sulfate-reducing bacterium, designated B15T, was isolated from supercooled water brine from within permafrost of the Varandey Peninsula, on the southern coast of the Barents Sea. Cells were Gram-negative, motile vibrions (3.0–4.0×0.4–0.5 µm) with a single polar flagellum. The isolate was positive for desulfoviridin as a bisulfite reductase. Strain B15T grew at −2 to 28 °C (optimum 24 °C) and with 0–2.0 % NaCl (optimum 0.2 %). The isolate used H2 plus acetate, formate, ethanol, lactate, pyruvate and choline as electron donors and used sulfate, sulfite, thiosulfate, elemental sulfur, DMSO and Fe3+ as electron acceptors. Pyruvate and lactate were not fermented in the absence of sulfate. The G+C content of genomic DNA was 55.2 mol%. Analysis of the 16S rRNA gene sequence showed that the isolate belonged to the genus Desulfovibrio. Its closest relatives were Desulfovibrio idahonensis CY1T (98.8 % 16S rRNA gene sequence similarity) and Desulfovibrio mexicanus Lup1T (96.5 %). On the basis of genotypic, phenotypic and phylogenetic characteristics, the isolate represents a novel species, for which the name Desulfovibrio arcticus sp. nov. is proposed; the type strain is B15T ( = VKM B-2367T = DSM 21064T).

Three Gram-negative, motile, aerobic bacteria were isolated from cultures of the marine red alga Porphyra yezoensis. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the novel strains were closely related to Maritalea myrionectae CL-SK30T (97.9 % 16S rRNA gene sequence similarity) and Zhangella mobilis E6T (96.2 %). 16S rRNA gene sequence similarity between Z. mobilis E6T and M. myrionectae CL-SK30T was 97.9 %. The DNA G+C contents of the isolates (49.4–50.0 mol%) were similar to those of M. myrionectae DSM 19524T (52.3 mol%) and Z. mobilis JCM 15144T (50.3 mol%). From these results, it was difficult to differentiate the genus Zhangella from the genus Maritalea. DNA–DNA hybridization demonstrated that the isolates belonged to a single species. The isolates could also be distinguished from M. myrionectae and Z. mobilis on the basis of chemotaxonomic and phenotypic features, including fatty acid composition (particularly C16 : 1ω7c), growth with 6–9 % (w/v) NaCl, carbon utilization, oxidation patterns and so on. A novel species of the genus Maritalea is proposed to accommodate the three isolates, with the name Maritalea porphyrae sp. nov. The type strain is LCM-3T ( = LMG 25872T = NBRC 107169T). Furthermore, it is proposed that Zhangella mobilis should be transferred from the genus Zhangella to the genus Maritalea, with the name Maritalea mobilis comb. nov. (type strain E6T = CGMCC 1.7002T = JCM 15144T).

An analysis of 16S rRNA gene sequences from archived clinical reference specimens identified a novel species of the genus Psychrobacter, of which four strains have been independently isolated from human blood. On the basis of 16S rRNA gene sequence similarity, the closest relatives with validly published names were Psychrobacter arenosus R7T (98.7 %), P. pulmonis CECT 5989T (97.7 %), P. faecalis Iso-46T (97.6 %) and P. lutiphocae IMMIB L-1110T (97.2 %). Maximum-likelihood phylogenetic analysis of 16S rRNA gene sequences showed that the isolates belonged to the genus Psychrobacter and were members of a cluster associated with Psychrobacter sp. PRwf-1, isolated from a silk snapper fish. DNA–DNA relatedness and partial 23S rRNA gene sequences also supported the finding that the isolates belonged to a species distinct from its closest phylogenetic neighbours. The predominant cellular fatty acids were C18 : 1ω9c, C16 : 0, summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), summed feature 5 (C18 : 2ω6,9c and/or anteiso-C18 : 0) and C18 : 0. Biochemical and morphological analysis further supported the assignment of the four isolates to a novel species. The name Psychrobacter sanguinis sp. nov. is proposed. The type strain is 13983T ( = DSM 23635T = CCUG 59771T).

A Gram-stain-negative, aerobic, motile, rod-shaped bacterial strain, GSW-M6T, was isolated from seawater of Geoje island, Korea, and was subjected to a polyphasic taxonomic study. Strain GSW-M6T grew optimally at pH 7.0–8.0, at 30 °C and in the presence of 2 % (w/v) NaCl. In the neighbour-joining phylogenetic tree based on 16S rRNA gene sequences, strain GSW-M6T clustered with Thalassobius aestuarii, Thalassobius gelatinovorus and Thalassobius mediterraneus. Strain GSW-M6T exhibited 96.2–96.9 % 16S rRNA gene sequence similarity to the type strains of these three Thalassobius species. Strain GSW-M6T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c as the major fatty acid. The polar lipid profiles of strain GSW-M6T and the type strains of the three Thalassobius species were similar, with phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine and an unidentified lipid as common major components. The DNA G+C content of strain GSW-M6T was 57 mol%. The mean level of DNA–DNA relatedness between strain GSW-M6T and the type strain of Thalassobius gelatinovorus was 17 %. Differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, enabled strain GSW-M6T to be differentiated from recognized species of the genus Thalassobius. On the basis of the data presented, strain GSW-M6T is considered to represent a novel species of the genus Thalassobius, for which the name Thalassobius maritimus sp. nov. is proposed. The type strain is GSW-M6T ( = KCTC 23347T  = CCUG 60021T).

A novel moderately thermophilic, red-pigmented bacterium, designated strain AZM34c11T, was isolated from the bottom of a 1000 m-deep drilled well located in a Japanese hot spring. Cells were Gram-negative and grew optimally at 50 °C, at pH 7.6 and with 0–0.3 % (w/v) NaCl. Analysis of the 16S rRNA gene sequence revealed that the isolate belonged to the genus Meiothermus. Levels of 16S rRNA gene sequence similarity between strain AZM34c11T and the type strains of recognized Meiothermus species were 88.2–94.8 %. Strain AZM34c11T was distinguished from recognized Meiothermus species by its cellular fatty acid profile: iso-C16 : 0 was one of the predominant components and hydroxy fatty acids were present only in trace amounts. The strain could also be differentiated based on its growth substrate preferences and characteristic enzyme reactions. On the basis of these results, strain AZM34c11T is considered to represent a novel species of the genus Meiothermus, for which the name Meiothermus hypogaeus sp. nov. is proposed. The type strain is AZM34c11T ( = NBRC 106114T  = DSM 23238T).

An aerobic, pink-pigmented, budding bacterium, designated strain S26T, was isolated from an acidic Sphagnum peat bog of north-western Russia. Cells were non-motile and spherical, occurring singly, in pairs or in short chains, and were able to attach to surfaces by means of a holdfast material. Strain S26T was a moderately acidophilic, mesophilic organism capable of growth at pH 3.2–7.1 (optimum at pH 4.8–5.0) and at 4–33 °C (optimum at 20–26 °C). Most sugars, several organic acids and polyalcohols were the preferred growth substrates. The major fatty acids were C16 : 0, C18 : 1ω9c and C18 : 2ω6c,12c. The major neutral lipids were n-C31 : 9 hydrocarbon and squalene; the polar lipids were phosphatidylglycerol, phosphatidylcholine and components with an unknown structure. The DNA G+C content of strain S26T was 62.2 mol%. 16S rRNA gene sequence analysis showed that strain S26T is a member of the order Planctomycetales. Among taxonomically characterized representatives of this order, highest levels of 16S rRNA gene sequence similarity (95.1–95.2 %) were observed with strains of the non-filamentous, peat-inhabiting planctomycete Singulisphaera acidiphila. Strain S26T could be differentiated from Singulisphaera acidiphila based on pigmentation, significant differences in substrate utilization patterns, greater tolerance of acidic conditions and the presence of C16 : 1ω9c. Based on the data presented, strain S26T is considered to represent a novel species of the genus Singulisphaera, for which the name Singulisphaera rosea sp. nov. is proposed; the type strain is S26T ( = DSM 23044T = VKM B-2599T).

Free-living bacteria with spherical cells 0.5–2.5 µm in diameter were isolated from freshwater sediment. 16S rRNA gene sequence analysis placed the new isolates within the phylum Spirochaetes (‘spirochaetes’). The isolates never displayed a helical morphology or motility. Growth occurred in the presence of 100 mg ampicillin l−1 in complex and defined mineral salts medium amended with vitamins, yeast extract and monosaccharides, disaccharides or soluble starch as fermentable substrates. Two distinct isolates, designated BuddyT and GrapesT, exhibited doubling times of 21±2 and 15±1 h in glucose-amended medium and grew at 15–37 and 15–30 °C. Optimum growth was observed between 25 and 30 °C and pH 6.5–7.5, with no growth below pH 5 or above pH 10. Hexose and pentose fermentation yielded ethanol, acetate and formate as major end products. Growth was strictly fermentative and anaerobic, but the isolates tolerated brief oxygen exposure. Nitrate, sulfate, thiosulfate and carbon dioxide were not used as electron acceptors, but soluble Fe(III) was reduced to Fe(II) in glucose-amended medium. The DNA G+C base contents of isolates BuddyT and GrapesT were 45.5–46.4 and 47.0–49.2 mol%, respectively. Phospholipid fatty acid (PLFA) profiles contained large proportions of C14 : 0 and C16 : 0 straight-chain saturated fatty acids; C16 : 1ω7c and C16 : 1ω9c dominated the mono-unsaturated PLFAs in isolate GrapesT, whereas isolate BuddyT also possessed C18 : 1ω5c, C18 : 1ω7c and C18 : 1ω9c fatty acids. Branched monoenoic acids accounted for up to 12.4 and 30 % of the total PLFA in isolates GrapesT and BuddyT, respectively. Based on their unique morphological features and the phylogenetic distance from their closest relatives, we propose the new genus, Sphaerochaeta gen. nov., to accommodate the new isolates within the novel species Sphaerochaeta globosa sp. nov. (type strain BuddyT  = DSM 22777T  = ATCC BAA-1886T) and Sphaerochaeta pleomorpha sp. nov. (type strain GrapesT  = DSM 22778T  = ATCC BAA-1885T). Sphaerochaeta globosa is the type species of the genus.

Bacterial strain TM-1T was isolated from the gut of a wood-feeding termite, Reticulitermes chinensis Snyder. Cells of strain TM-1T were Gram-negative, spherical (1.0–2.0 µm in diameter), non-motile, non-sporulating and red-pigmented. Strain TM-1T was resistant to UV radiation, showing 34 % survival after exposure to UV light at a dose of 100 J m−2. Growth occurred at 20–40 °C (optimum, 30 °C), at pH 6.0–10.0 (optimum, pH 6.0–7.0), and in the presence of 0–1 % (w/v) NaCl (optimum, 0–0.4 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain TM-1T was related to members of the genus Deinococcus, with sequence similarities ranging from 87.0 to 94.0 %. The peptidoglycan of strain TM-1T contained ornithine, alanine, glycine and glutamic acid. The most abundant cellular fatty acids of strain TM-1T were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 22.3 %) and C16 : 0 (37.5 %). MK-8 was the predominant quinone. The polar lipid profile contained three glycophospholipids, six glycolipids, one aminolipid and three unknown lipids. DNA of the type strain had a G+C content of 65.6 mol%. Based on the phylogenetic, chemotaxonomic and phenotypic data presented, strain TM-1T represents a novel species of the genus Deinococcus, for which the name Deinococcus reticulitermitis sp. nov. is proposed, with TM-1T ( = CGMCC 1.10218T = NBRC 106334T) as the type strain.

Most bacteria recovered so far from sugar thick juice during storage represent strains of the species Tetragenococcus halophilus. Recently, several Gram-positive, non-motile, non-spore-forming cocci with other physiological and genetic traits were isolated from sugar thick juice samples from different origins. In this study, representative isolates were investigated using a polyphasic taxonomic approach. The 16S rRNA gene sequence similarity between these isolates and their closest relative, Tetragenococcus muriaticus, was 97.4 %. The level of DNA–DNA relatedness between isolate T1T, representing the newly found Tetragenococcus isolates, and T. muriaticus was 57 %. Isolate T1T had a DNA G+C content of 36.7 mol%. Phylogenetic data and genomic and phenotypic features demonstrated that the isolates represent a novel species, for which the name Tetragenococcus osmophilus sp. nov. is proposed with T1T as the type strain ( = LMG 26041T  = DSM 23765T). Additionally, T. halophilus isolates from high-salt and high-sugar environments showed clear differences in several physiological and genetic characteristics like RAPD fingerprints and 16S rRNA gene sequences. DNA–DNA hybridizations, however, showed 79 to 80 % relatedness between osmophilic and halophilic T. halophilus isolates, demonstrating that the different strains belong to the same species. Based on the phenotypic and genotypic differences observed, as well as the different origins of the strains and the industrial relevance of thick juice degradation, two subspecies of T. halophilus are described in this manuscript: T. halophilus subsp. halophilus subsp. nov. for the strains isolated from salt media and T. halophilus subsp. flandriensis subsp. nov. for the strains isolated from sugar-rich environments, which were first isolated in Flanders, Belgium. The type strains for the subspecies are IAM 1676T ( = LMG 11490T  = DSM 20339T) and T5T ( = LMG 26042T  = DSM 23766T), respectively.

A strictly anaerobic, cellulolytic strain, designated 18P13T, was isolated from a human faecal sample. Cells were Gram-positive non-motile cocci. Strain 18P13T was able to degrade microcrystalline cellulose but the utilization of soluble sugars was restricted to cellobiose. Acetate and succinate were the major end products of cellulose and cellobiose fermentation. 16S rRNA gene sequence analysis revealed that the isolate belonged to the genus Ruminococcus of the family Ruminococcaceae. The closest phylogenetic relative was the ruminal cellulolytic strain Ruminococcus flavefaciens ATCC 19208T (<95 % 16S rRNA gene sequence similarity). The DNA G+C content of strain 18P13T was 53.05±0.7 mol%. On the basis of phylogenetic analysis, and morphological and physiological data, strain 18P13T can be differentiated from other members of the genus Ruminococcus with validly published names. The name Ruminococcus champanellensis sp. nov. is proposed, with 18P13T ( = DSM 18848T = JCM 17042T) as the type strain.