Chitinimonas arctica sp. nov., isolated from Arctic tundra soil.

A Gram-stain-negative, rod-shaped, green-pigmented, aerobic and motile bacterium, strain R3-44T, was isolated from Arctic tundra soil. Stain R3-44T clustered closely with members of the genus Chitinimonas, which belongs to the family Burkholderiaceae, and showed the highest 16S rRNA sequence similarity to Chitinimonas naiadis AR2T (96.10%). Strain R3-44T grew optimally at pH 7.0, 28 °C and in the presence of 0-0.5 % (w/v) NaCl. The predominant respiratory isoprenoid quinone of strain R3-44T was identified as ubiquinone Q-8. The polar lipids consisted of phosphatidylglycerol, phosphatidylethanolamine, unidentified aminolipid and unidentified phospholipid. The main fatty acids were summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c, 40.6 %) and C16 : 0 (29.3 %). The DNA G+C content of strain R3-44T was 60.8 mol%. On the basis of the evidence presented in this study, strain R3-44T represents a novel species of the genus Chitinimonas, for which the name Chitinimonas arctica sp. nov. is proposed, with the type strain R3-44T (=CCTCC AB 2010422T=KCTC 72602T).

Nakamurella antarctica sp. nov., isolated from Antarctica South Shetland Islands soil.

A pale-yellow bacterial strain, designated S14-144T, was isolated from tundra soil sampled near the Antarctic Peninsula, South Shetland Islands (62° 22' 34″ S, 59° 42' 34″ W). The cells were strictly aerobic, Gram-stain-positive, non-motile and coccoid-shaped. Growth occurred at 4-28 °C, at pH 5.0-9.0 and in the presence of 0-5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain S14-144T formed a lineage within the genus Nakamurella and shared the highest 16S rRNA gene sequence similarity with Nakamurella deserti 12Sc4-1T (96.5 %) and Nakamurella silvestrisS20-107T (96.4 %). The average nucleotide identity value between the genomes of strain 14-144T and the type strain of the species, N. deserti, was 72.0 % . The DNA G+C content of strain S14-144T was 61.6 mol% . The major cellular fatty acids of strain S14-144T were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and C16 : 0. The strain contained MK-8(H4) as the predominant respiratory quinone, phosphatidylethanolamine and diphosphatidylglycerol as the major polar lipids, rhamnose, ribose and glucose as the major whole-cell sugars, and meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. On the basis of the phylogenetic, phenotypic and chemotaxonomic analysis, strain S14-144T is considered to represent a novel species of the genus Nakamurella, for which the name Nakamurella antarctica sp. nov. is proposed. The type strain is S14-144T (=CCTCC AB 2015345T=KCTC 39796T).

Undibacterium arcticum sp. nov., isolated from arctic alpine soil.

A Gram-stain-negative, aerobic, motile rod-shaped bacterium, designated 6-67T, was isolated from a soil sample collected from Longyearbyen, Svalbard. Its taxonomic position was investigated by genotypic, phenotypic and chemotaxonomic analyses. This isolate grew at 4-28 °C (optimum, 20 °C), at pH 5.0-9.0 (optimum, pH 7.0) and with 0-0.2 % (w/v) NaCl. Strain 6-67T contained Q-8 as a major respiratory quinone and MK-7 as a minor component; the major fatty acids were summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) and C16 : 0. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, two unidentified phospholipids and one unidentified aminophospholipid. The polyamines were putrescine and 2-hydroxyputrescine. 16S rRNA gene sequence analysis indicated that the novel strain 6-67T belonged to the family Oxalobacteraceae within the class Betaproteobacteria. The DNA G+C content of strain 6-67T was 56.21 mol%. On the basis of phylogenetic, physiological and chemotaxonomic data, strain 6-67T is considered to represent a novel species of the genus Undibacterium, for which the name Undibacterium arcticum sp. nov. is proposed. The type strain is 6-67T (=CCTCC AB 2015162T=KCTC 42986T).

Mucilaginibacter antarcticus sp. nov., isolated from tundra soil.

The novel, pale yellow bacterial strain, designated S14-88T, was isolated from a tundra soil near Antarctic Peninsula, South Shetland Islands, and its taxonomic position was investigated by a genotypic and phenotypic analysis. Cells were facultatively anaerobic, Gram-stain-negative, non-motile and rod-shaped. Growth occurred at 4-28 °C (optimum at 15 °C), at pH 7.0-8.0 (optimum at 7.0) and with 0-0.6 % (w/v) NaCl (optimum, no NaCl). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain S14-88T formed a lineage within the genus Mucilaginibacter. The 16S rRNA gene sequence similarity between strain S14-88T and the type strains of related species ranged from 92.2 to 96.5 %, and the 16S rRNA gene sequence of S14-88T showed highest similarity of 96.5 % to Mucilaginibacter soyangensis HME6664T. The major cellular fatty acids of strain S14-88T were iso-C15 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The major respiratory quinone was menaquinone MK-7, and the main polar lipid was phosphatidylethanolamine. The DNA G+C content of strain S14-88T was 42.3 mol%. On the basis of the evidence presented in this study, strain S14-88T is considered to represent a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter antarcticus sp. nov. is proposed. The type strain is S14-88T (=CCTCC AB 2015321T=KCTC 52232T).

Pseudorhodobacter collinsensis sp. nov., isolated from a till sample of an icecap front.

A Gram-stain-negative, rod-shaped, aerobic and non-motile strain, designated 4-T-34T, was isolated from a till sample of Collins icecap front, Antarctica, and its taxonomic position was investigated by genotypic, phenotypic and chemotaxonomic analysis. The isolate grew at 4-30 °C (optimum 20-25 °C), at pH 6.0-10.0 and with 0-1.0 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 4-T-34T belonged to the genus Pseudorhodobacter, with the closest relatives being Pseudorhodobacter wandonensis WT-MW11T (96.9 % 16S rRNA gene sequence similarity), Pseudorhodobacter antarcticus ZS3-33T (96.8 %), Pseudorhodobacter ferrugineus IAM 12616T (96.5 %) and Pseudorhodobacter aquimaris HDW-19T (95.4 %). Strain 4-T-34T contained Q-10 as the only ubiquinone and C18 : 1ω7c as the major fatty acid. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, two unidentified aminophospholipids and two unidentified phospholipids. The DNA G+C content of strain 4-T-34T was 61 mol%. On the basis of phylogenetic, physiological and chemotaxonomic data, strain 4-T-34T is considered to represent a novel species of the genus Pseudorhodobacter, for which the name Pseudorhodobacter collinsensis sp. nov. is proposed. The type strain is 4-T-34T ( = CCTCC AB 2014005T = LMG 28256T).

Chryseobacterium frigidum sp. nov., isolated from high-Arctic tundra soil, and emended descriptions of Chryseobacterium bernardetii and Chryseobacterium taklimakanense.

A yellow, Gram-reaction-negative, non-motile, aerobic bacterium, designated D07T, was isolated from a tundra soil near Ny-Ålesund, Svalbard archipelago, Norway (78° N). Growth occurred at 4-37 °C (optimum 28-30 °C) and at pH 6.0-9.0 (optimum pH 7.0-8.0). The strain produced flexirubin-type pigments. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain D07T belonged to the genus Chryseobacterium in the family Flavobacteriaceae. The 16S rRNA gene sequence of this strain showed 93.83 and 93.31 % sequence similarity, respectively, to those of Chryseobacterium contaminans C26T and Chryseobacterium taklimakanense X-65T. Strain D07T contained anteiso-C15 : 0 (25.91 %), iso-C15 : 0 (16.05 %), iso-C16 : 0 3-OH (9.64 %), iso-C16 : 0 (9.42 %) and iso-C14 : 0 (7.36 %) as the predominant cellular fatty acids, MK-6 as the major respiratory quinone and phosphatidylethanolamine, five unknown aminolipids and three unknown lipids as the main polar lipids. The DNA G+C content was 49.3 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain D07T is considered to represent a novel species of the genus Chryseobacterium, for which the name Chryseobacterium frigidum sp. nov. is proposed. The type strain is D07T ( = CCTCC AB 2011160T = KCTC 42897T). Emended descriptions of Chryseobacterium bernardetii and Chryseobacterium taklimakanense are also provided.

Flavobacterium collinsense sp. nov., isolated from a till sample of an Antarctic glacier.

A novel rod-shaped, Gram-stain-negative, non-gliding and aerobic strain surrounded by a multilayer capsule, designated 4-T-2T, was isolated from a till sample of Collins glacier front, Antarctica. The bacterium formed yellow, circular, convex and smooth colonies. Growth occurred at 4-28 °C (optimum18-20 °C), at pH 7.0-10.0 (optimum pH 9.0) and with 0-1 % NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 4-T-2T belonged to the genus Flavobacterium. Strain 4-T-2T shared the highest 16S rRNA gene sequence similarity with the type strain of Flavobacterium algicola (96.7 %). The DNA G+C content of strain 4-T-2T was 36.2 mol%. The only menaquinone was MK-6. The major cellular fatty acids were iso-C15 : 0, iso-C15 : 1 G, iso-C16 : 0 and summed feature 9 (comprising iso-C17 : 1ω9c and/or 10-methyl C16 : 0). Polar lipid profile consisted phosphatidylethanolamine, one unidentified aminolipid, one unidentified aminophospholipid and one unidentified lipid. On the basis of phylogenetic, physiological and chemotaxonomic data, strain 4-T-2T is considered to represent a novel species of the genus Flavobacterium, for which the name Flavobacterium collinsense sp. nov. is proposed. The type strain is 4-T-2T ( = CCTCC AB 2014004T = LMG 28257T).

Roseomonas arctica sp. nov., isolated from arctic glacial foreland soil.

A novel psychrotolerant bacterium, designed strain M6-79T, was isolated from an arctic glacial foreland soil sample collected from Ny-Ålesund in the Svalbard Archipelago, Norway. Cells of strain M6-79T were Gram-stain-negative, rod-shaped and produced a red-pigment. Strain M6-79T was strictly aerobic, non-motile, non-endospore-forming, oxidase-negative and catalase-positive. Based on 16S rRNA gene sequence analysis, strain M6-79T was phylogenetically related to Roseomonas aquatica TR53T (95.2 % 16S rRNA gene sequence similarity), Roseomonas lacus TH-G33T (94.3 %), 'Roseomonas sediminicola' FW-3 (94.3 %), Roseomonas terrae DS-48T (94.1 %) and Roseomonas soli 5N26T (94.1 %). The unique isoprenoid quinone detected in strain M6-79T was Q-9. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, one unknown aminolipid and one unknown lipid. Strain M6-79T possessed C18 : 1ω7c, C16 : 0 and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) as the predominant fatty acids, and the DNA G+C content was 71.2 mol%. Combined data from phylogenetic, phenotypic and chemotaxonomic studies revealed that strain M6-79T represents a novel species of the genus Roseomonas, for which the name Roseomonas arctica sp. nov. is proposed. The type strain is strain M6-79T ( = CCTCC AB 2013101T = LMG 28251T).

Pedobacter ardleyensis sp. nov., isolated from soil in Antarctica.

A red-pigmented, non-motile, Gram-stain-negative, rod-shaped bacterium, strain R2-28T, was isolated from a soil sample collected from Ardley Island, South Shetland Islands, Antarctica, and was characterized taxonomically by using a polyphasic approach. The organism grew optimally at 18 °C in TSB. On the basis of phylogenetic analyses of the 16S rRNA gene sequence, strain R2-28T was most closely related to the genus Pedobacter of the family Sphingobacteriaceae. The highest levels of 16S rRNA gene sequence similarity were found with respect to Pedobacter alluvionis NWER-II11T (95.6 %) and Pedobacter terrae DS-57T (95.2 %). The DNA G+C content was 39.9 mol%, and MK-7 was the only respiratory quinone. The major polar lipids were phosphatidylethanolamine and a sphingolipid. The predominant cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c). These chemotaxonomic and phylogenetic data supported the allocation of strain R2-28T to the genus Pedobacter. Additionally, the results of physiological and biochemical tests allowed phenotypic differentiation of strain R2-28T from species of the genus Pedobacter with validly published names. Therefore, strain R2-28T represents a novel species within the genus Pedobacter, for which the name Pedobacter ardleyensis sp. nov. is proposed. The type strain is R2-28T ( = CCTCC AB 2013365T = LMG 28255T).

Roseovarius antarcticus sp. nov., isolated from a decayed whale bone.

A pale yellow, ovoid- to rod-shaped and budding bacterium, designated strain M-S13-148(T), was isolated from a decayed bone of whale from the eastern coast of King George Island, South Shetlands, Antarctica. Strain M-S13-148(T) exhibited motility, aerobic growth and was Gram-stain-negative. Strain M-S13-148(T) was positive for catalase and oxidase. Growth was observed at pH 6.0-9.0, at 4-42 °C and with 0-14% (w/v) NaCl. The novel strain contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and an unknown phospholipid as the major polar lipids. The dominant cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), (58.8%) and C16 : 0 (11.7%). The respiratory quinone was Q-10 and the DNA G + C content was 60.9 mol%. Neighbour-joining, maximum-likelihood and minimum-evolution phylogenetic trees, based on 16S rRNA gene sequences, indicated that strain M-S13-148(T) belonged to the genus Roseovarius and was most closely related to Roseovarius nanhaiticus CCTCC AB 208317(T) (93.72% 16S rRNA gene sequence similarity). The 16S rRNA gene sequence similarity with respect to members of the genus Roseovarius ranged from 91.81 to 93.94%. On the basis of phenotypic, molecular and chemotaxonomic characteristics, strain M-S13-148 is considered to represent a novel species of the genus Roseovarius, for which the name Roseovarius antarcticus sp. nov., is proposed. The type strain is M-S13-148(T) ( = CCTCC AB2014072(T) = LMG 28420(T)).

Desertibacter xinjiangensis sp. nov., isolated from the soil of a Euphrates poplar forest, and emended description of the genus Desertibacter.

A pale pink and strictly aerobic bacterium, designated strain M71(T), was isolated from the soil of a Euphrates poplar forest in Xingjiang, PR China. Cells of the strain were Gram-reaction-negative, rod-shaped and motile by means of a single polar flagellum. Growth occurred at 10-37 °C (optimum 30 °C), at pH 6.0-9.0 (optimum pH 7.0-8.0) and with 0-2.0% NaCl (w/v, optimum 0%). Phylogenetic analysis, based on 16S rRNA gene sequences, indicated that strain M71(T) belongs to the genus Desertibacter in the family Rhodospirillaceae. The 16S rRNA gene sequence of this strain showed 96.2% sequence similarity with the type strain of Desertibacter roseus 2262(T). The respiratory quinone was Q-10 and the predominant cellular fatty acids were C(18:1)ω7c (53.2%), C(16:1)ω5c (11.0%), summed feature 3 (C(16:1)ω7c and/or C(16:1)ω6c, 10.2%) and C(16:0) (8.5%). The DNA G+C content was 71.2 mol% (HPLC). The strain contained phosphatidylcholine and phosphatidylethanolamine as the predominant polar lipids. On the basis of the phenotypic, chemotaxonomic and phylogenetic data, strain M71(T) is considered to represent a novel species of the genus Desertibacter, for which the name Desertibacter xinjiangensis sp. nov. is proposed. The type strain is M71(T) ( =CCTCC AB 209291(T) =CIP 110127(T)).