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A Gram-stain-negative, rod-shaped, aerobic and non-motile strain, designated 4-T-34 T , 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 8C (optimum 20-25 8C), 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-MW11 T (96.9 % 16S rRNA gene sequence similarity), Pseudorhodobacter antarcticus The genus Pseudorhodobacter, which belongs to the class Alphaproteobacteria, was first proposed by Uchino et al. 1992;Jung et al., 2012;Chen et al., 2013;Lee et al., 2013). The purpose of the present study was to determine the taxonomic position of strain 4-T-34 T by using a polyphasic approach and to propose that the strain represents a novel species of the genus Pseudorhodobacter.The till sample was collected from Collins icecap front (628 10.9379 S 588 52.0019 W) in Antarctica. The sample was diluted serially with a sterile 0.85 % (w/v) NaCl solution, and these dilutions were plated onto tryptic soy agar (TSA; BD) and incubated at 4 8C for 30 days. Strain 4-T-34 T was isolated from these TSA plates and cultivated routinely on R2A plates (BD) at 20 8C under aerobic conditions. Colonial morphology was observed after incubation on R2A agar for 3-10 days at 20 8C. Cell morphology was examined by phasecontrast (BX51; Olympus) and transmission electron (Tecnai) microscopy. Gram staining of cells was carried out according to the classical Gram-stain procedure described by Doetsch (1981). Growth was evaluated at 20 8C on several standard bacteriological media (all from BD): R2A agar, 0.36R2A agar, marine broth 2216 (MB) agar, TSA and nutrient agar (NA). Growth at different temperatures (4, 10, 18, 20, 25, 28, 30, 37 and 42 8C) was investigated on R2A agar for up to 4 weeks. The pH range for growth was determined in R2A

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-S13-148T exhibited motility, aerobic growth and wasGram-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 8C 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 (C 18 : 1 v7c and/or C 18 : 1 v6c), (58.8 %) and C 16 : 0 (11.7 %). The respiratory quinone was Q-10 and the DNA G+C content was 60.9 mol%. Neighbour-joining, maximumlikelihood 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 (5CCTCC AB2014072 T 5LMG 28420 T ).

A red-pigmented, non-motile, Gram-stain-negative, rod-shaped bacterium, strain R2-28 T , 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 8C in TSB. On the basis of phylogenetic analyses of the 16S rRNA gene sequence, strain R2-28 T 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-II11 T (95.6 %) and Pedobacter terrae DS-57 T (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-C 15 : 0 , anteiso-C 15 : 0 , iso-C 17 : 0 3-OH and summed feature 3 (comprising C 16 : 1 v7c and/or C 16 : 1 v6c). These chemotaxonomic and phylogenetic data supported the allocation of strain R2-28 T to the genus Pedobacter. Additionally, the results of physiological and biochemical tests allowed phenotypic differentiation of strain R2-28 T from species of the genus Pedobacter with validly published names. Therefore, strain R2-28 T represents a novel species within the genus Pedobacter, for which the name Pedobacter ardleyensis sp. nov. is proposed. The type strain is R2-28 T (5CCTCC AB 2013365 T 5LMG 28255 T ).The genus Pedobacter and the family Sphingobacteriaceae were described by Steyn et al. (1998). Subsequently, the description of the genus has been emended by Vanparys et al. (2005), Hwang et al. (2006, Gallego et al. (2006) and Zhou et al. (2012). At the time of writing, the genus Pedobacter comprised 46 species. All members of the genus are obligately aerobic, non-endospore-forming, Gram-stain-negative rods that lack flagella and are negative for urease, gelatinase and indole production (Margesin & Zhang, 2013). All members of the genus Pedobacter contain menaquinone 7 (MK-7) as the major respiratory quinone and have DNA G+C contents in the range 36-45 mol%. Furthermore, they have been confirmed to possess phosphatidylethanolamine and sphingolipids (Zhou et al., 2012). Members of the genus Pedobacter have been isolated from various terrestrial and aquatic environments such as soil, drinking water, activated sludge, glacier cryoconite, glacial water, a nitrifying inoculum, a hypertrophic pond and sediment (Hwang et al., 2006;An et al., 2009;Gallego et al., 2006; Kwon et al., 2007Kwon et al., , 2011Lee et al., 2009;Luo et al., 2010;Margesin et al., 2003;Roh et al., 2008;Shivaji et al., 2005;Tang et al., 2010;Vanparys et al., 2005). In this study, an Antarctic bacterial isolate was subjected to a polyphasic analysis and was identified as a novel member of the genus Pedobacter.The soil sample was collected from a penguin colony on Ardley Island, Antarctica (628 12.6889 S 588 55.7289 W). At the time of sampling, the soil had a pH of 6.0 and a temperature of 3.0 8C at 5 cm below the surface. T...

A novel rod-shaped, Gram-stain-negative, non-gliding and aerobic strain surrounded by a multilayer capsule, designated 4-T-2 T , 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 8C (optimum18-20 8C), 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-2 T belonged to the genus Flavobacterium. Strain 4-T-2 T 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-2 T was 36.2 mol%. The only menaquinone was MK-6. The major cellular fatty acids were iso-C 15 : 0 , iso-C 15 : 1 G, iso-C 16 : 0 and summed feature 9 (comprising iso-C 17 : 1 v9c and/or 10-methyl C 16 : 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-2 T 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-2 T (5CCTCC AB 2014004 T 5LMG 28257 T ).The genus Flavobacterium of the family Flavobacteriaceae in phylum Bacteroidetes was first proposed by Bergey et al. (1923) and most recently emended by Kuo et al. (2013). Most members of the genus are characterized as rod-shaped Gram-stain-negative, aerobic, produce yellow-pigment, and contain MK-6 as the major respiratory quinone and iso-C 15 : 0 as the major fatty acid (Bernardet et al., 1996). Phosphatidylethanolamine is the common major polar lipid in the genus . At the time of writing, the genus Flavobacterium contained 142 species with validly published names, which have been isolated from various habitats, such as soil, sediment, water, glacier samples and diseased animals. The genus Flavobacterium comprises many coldadapted species isolated from Antarctica in the past 20 years, including F. faecale (Kim et al., 2014) (McCammon & Bowman, 2000); F. hibernum (McCammon et al., 1998).The aim of the present work was to determine the taxonomic position, using a polyphasic approach, of strain 4-T-2 T , which was also isolated from Antarctica and proposed to represent a novel species of the genus Flavobacterium.Strain 4-T-2 T was isolated from a till sample collected from Collins glacier front (628 10.9379 S 588 52.0019 W) in Antarctica. Isolation was carried out using the standard dilution plating method on R2A agar (BD) at 4 8C. The novel strain was routinely cultured on R2A agar and stored by lyophilization.Sequencing of the 16S rRNA gene of strain 4-T-2 T was carried out as described by Weisburg et al. (1991). The 16S rRNA gene sequence (1412 bp) was obtained using the bacterial primers set 27F (59-AGAGTTTGATCCTGGC-TCAG-39) and 1540R (59-AAGGAGGTGATCCAGCC-39) and was subjected to comparative analysis. Sequence similarity was investigated usi...