Polyphasic taxonomic characterisation of a novel strain as Pararhizobium haloflavum sp. nov., isolated from soil samples near a sewage treatment tank.

A Gram-stain negative, aerobic, motile and ovoid- to rod-shaped bacteria strain, designated XC0140T, was isolated from soil samples near the sewage treatment tank of a chemical factory in Zhejiang Province, China, and subjected to polyphasic taxonomic investigation. Strain XC0140T grew at 10-37 °C and pH 6.0-9.0 (optimum, 35 °C and pH 7.5) and with 0-17% (w/v) NaCl (optimum, 1%). According to phylogenetic analysis based on 16S rRNA gene sequences, strain XC0140T was assigned to the genus Pararhizobium with high 16S rRNA gene sequence similarity of 95.97% to "Pararhizobium helanshanense CCNWQTX14T", followed by Pararhizobium sphaerophysae CCNWGS0238T (95.95%). Chemotaxonomic analysis showed that strain XC0140T contains ubiquinone-10 as the predominant respiratory quinone and possessed summed feature 8 (comprising C18: 1 ω7c and/or ω6c), 11-methyl C18:1 ω7c, C18: 0 and C16: 0 as predominant forms of fatty acids. The polar lipids of strain XC0140T consisted of seven phospholipids (PL), two aminolipids (AL), one glycolipid (GL) and three unidentified lipids (L1, L2 and L3). The DNA G+C content was 62.7 mol%. Based on the polyphasic taxonomic characterization, strain XC0140T is considered to represent a novel species of the genus Pararhizobium, for which the name Pararhizobium haloflavum sp. nov. is proposed. (type strain XC0140T = MCCC 1K03228T = KCTC 52582T).

Hyphobacterium vulgare gen. nov., sp. nov., a novel alphaproteobacterium isolated from seawater.

A Gram-stain-negative, aerobic, non-spore-forming, non-motile, oval to rod-shaped, prosthecate bacterium, designated strain WM6T, was isolated from a seawater sample collected from the South China Sea at a depth of 150 m and subjected to a polyphasic taxonomic investigation. Cells of strain WM6T were approximately 0.5-0.6 µm in width and 0.8-1.2 µm in length, and colonies were smooth, circular, convex and whitish yellow. Strain WM6T was found to grow at 10-45 °C (optimum, 30 °C), at pH 6.5-9.0 (optimum, pH 7.5-8.5) and with 1-6 % (w/v) NaCl (optimum, 1-2 %). Chemotaxonomic analysis showed the predominant respiratory quinone and the major fatty acid of strains WM6T were ubiquinone-10 and C18 : 1ω7c, respectively. The polar lipids of strain WM6T were phosphatidylglycerol, glucuronopyranosyldiglyceride, monoglycosyldiglyceride, sulfo-quinovosyl diacylglycerol, seven unknown glycolipids and two unknown lipids. The DNA G+C content of strain WM6T was determined to be 59.8 mol% by HPLC. 16S rRNA gene sequence similarities showed that strain WM6T was related most closely to the genus Maricaulis with a similarity range from 92.3 to 93.8 %. Phylogenetic trees reconstructed with the neighbour-joining and maximum-likelihood methods using mega and maximum-likelihood methods using arb showed that strain WM6T constituted a separated branch in the family Hyphomonadaceae. Differential phenotypic properties, together with phylogenetic distinctiveness, demonstrated that strain WM6T is clearly distinct from any validly published genus. On the basis of these features, strain WM6T represents a novel species of a new genus with the name Hyphobacterium vulgare gen. nov., sp. nov. The type strain of Hyphobacterium vulgare is WM6T (=MCCC 1K03222T=KCTC 52487T).

Chryseobacterium lineare sp. nov., isolated from a limpid stream.

A Gram-stain-negative, aerobic, non-motile, rod-shaped, yellow-pigmented bacterial strain, XC0022T, isolated from freshwater of a limpid stream in Zhejiang, China, was studied using a polyphasic approach. The phylogenetic analysis based on 16S rRNA gene sequences clearly showed an allocation to the genus Chryseobacterium with the highest sequence similarities of 98.0 % to Chryseobacterium taeanense PHA3-4T, 97.2 % to Chryseobacterium taihuense THMBM1T, 97.1 % to Chryseobacterium rigui CJ16T and 97.1 % to Chryseobacteriumprofundimaris DY46T. 16S rRNA gene sequence similarities to all other species of the genus Chryseobacterium were below 97.0 % (92.3-96.8 %). DNA-DNA hybridization results showed that strain XC0022T was 55.3 %, 49.8 % and 31.1 % related to C. taeanense DSM 17071T, Chryseobacteriumtaichungense DSM 17453T and Chryseobacteriumgleum JCM 2410T, respectively. The quinone system was composed only of MK-6. Strain XC0022T possessed iso-C15 : 0, iso-C17 : 0 3-OH, C18 : 1ω9c and summed feature 3 (iso-C15 : 0 2-OH/C16 : 1ω7c) as the major fatty acids. The polar lipids profile consisted of one phosphatidylethanolamine, one unidentified glycolipid, four unidentified aminolipids and two unidentified lipids. The G+C content of the genomic DNA was 29.7 mol%. On the basis of phenotypic, phylogenetic and chemotaxonomic data, strain XC0022T (=KCTC 52364T=MCCC 1K02723T) represents a novel species of the genus Chryseobacterium, for which the name Chryseobacterium lineare sp. nov. is proposed.