A Gram-negative, non-spore-forming, non-motile bacterium, strain A8-7 T , was isolated from fresh water of a slightly alkaline lake, Longhu Lake, in Daqing, north-east China, and its taxonomic position was studied by using a polyphasic approach. Strain A8-7 T was aerobic, heterotrophic and positive for catalase and oxidase. It grew at 20-37 6C (optimum 30 6C) and pH 5.5-10.5 (optimum pH 7.5) and in the presence of 0-3 % (w/v) NaCl. It formed pink-pigmented, smooth and circular colonies, 1-2 mm in diameter, on R3A-V agar plates after incubation at 30 6C for 3 days. Cells of strain A8-7 T were rods, 0.2-0.4 mm wide and 1.6-4.0 mm long. The major fatty acids (.10 %) were iso-C 15 : 0 (40.3 %) and summed feature 3 (C 16 : 1 v7c and/or iso-C 15 : 0 2-OH; 12.1 %). The menaquinone was MK-7. The DNA G+C content was 43 mol% (T m ). Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain A8-7 T was phylogenetically related to members of the genus Algoriphagus, with sequence similarities of 92.6-95.2 %, the highest sequence similarity being to the sequence from Algoriphagus mannitolivorans IMSNU 14012 T . On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain A8-7 T was considered to represent a novel species of the genus Algoriphagus, for which the name Algoriphagus aquatilis sp. nov. is proposed. The type strain is A8-7 T (5CGMCC

Rheinheimera longhuensis sp. nov., isolated from a slightly alkaline lake, and emended description of genus Rheinheimera Brettar et al. The bacterial strain LH2-2 T was isolated from freshwater of Longhu Lake, a slightly alkaline lake (pH 8.8) in north-east China. Cells of strain LH2-2 T were Gram-staining-negative, non-sporeforming rods, 0.3-0.5 mm wide and 2.0-4.0 mm long. Cells were motile by means of a single polar flagellum. The strain was strictly aerobic and heterotrophic and oxidase-and catalase-positive. Growth occurred at 0-36 6C (optimum, 26-34 6C), pH 6.5-11 (optimum, pH 8.0-8.6) and in the presence of 0-2 % (w/v) NaCl (optimum, 1 %). Strain LH2-2 T contained Q-8 as the major respiratory quinone. The major fatty acids were summed feature 3 (C 16 : 1 v7c and/or iso-C 15 : 0 2-OH; 21.9 %), C 17 : 1 v8c (18.9 %), C 18 : 1 v7c (16.4 %) and C 16 : 0 (12.7 %) after growth on marine agar 2216. The DNA G+C content was 47 mol% (T m ). The 16S rRNA gene and a conserved portion of the gyrB gene were sequenced and used for phylogenetic analyses. Phylogenetic trees based on 16S rRNA gene and gyrB sequences showed that strain LH2-2 T was associated with the genus Rheinheimera and closely related to the type strains of Rheinheimera species, and showed the highest 16S rRNA gene sequence similarity to Rheinheimera pacifica KMM 1406 ). An emended description of the genus Rheinheimera is also provided.The genus Rheinheimera, a branch of the gammaproteobacteria, was created by Brettar et al. et al., 2011). Members of Rheinheimera have mostly been isolated from aquatic environments (except for R. soli, R. nanhaiensis and R. tangshanensis, which were isolated from soil, marine sediments and plant roots, respectively), including seawater (R. baltica, R. pacifica, R. perlucida and R. aquimaris) and freshwater (R. texasensis, R. aquatica and R. chironomi; the latter was isolated from a chironomid egg mass sampled from river water). Species of Rheinheimera are able to grow on and to degrade rapidly the more easily degradable organic fraction of marine organic matter (Bianchi & Bianchi, 1995;Pinhassi & Berman, 2003;Poretsky et al., 2005), suggesting that they may play important roles in aquatic environments in biogeochemical cycling of elements such as carbon. In this communication, a freshwater bacterial isolate capable of growth at 0 u C, strain LH2-2 T , was investigated for its taxonomic position by a polyphasic approach.

A Gram-negative, rod-shaped, non-pigmented, non-spore-forming bacterial strain that was motile by a single polar flagellum, designated A1-9 T , was isolated from Daqing reservoir in north-east China and its taxonomic position was studied using a polyphasic approach. Strain A1-9 T was non-halophilic, strictly aerobic and heterotrophic and lacked carotenoids, internal membranes and genes for photosynthesis (puf genes). Strain A1-9 T grew at 10-40 6C (optimum, 25-30 6C) and pH 5.5-9.0 (optimum, pH 6.0-6.5) and tolerated up to 1.0 % NaCl (w/v). Neither phototrophic nor fermentative growth was observed. The predominant ubiquinone was Q-10 and the major fatty acid was C 18 : 1 v7c (70 %). The DNA G+C content was 64.4 mol% (T m ). Phylogenetic analyses based on the 16S rRNA gene sequence revealed that strain A1-9 T , together with Catellibacterium nectariphilum AST4 T , formed a deep line within the 'Rhodobacter clade' of the family Rhodobacteraceae and strain A1-9 T showed 94.2 % 16S rRNA gene sequence similarity to C. nectariphilum AST4 T . On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain A1-9 T is considered to represent a novel species of the genus Catellibacterium, for which the name Catellibacterium aquatile sp. nov. is proposed. The type strain is A1-9 T (5CGMCC 1.7029 T 5NBRC 104254 T ).

A Gram-negative bacterium, designated B2-9 T , was isolated from water of a slightly alkaline lake, Longhu Lake in Daqing, north-east China. Strain B2-9T was an aerobic rod, heterotrophic, catalase-and oxidase-positive and motile by means of a single polar flagellum. The isolate grew well on n-alkanes C 9 -C 17 and weakly on C 6 -C 8 , C 18 and C 19 . Growth occurred at 10-37 6C (optimum 20-25 6C), at pH 5.5-9.5 (optimum pH 7.0) and with ¡1.0 % (w/v) NaCl. The major fatty acids were C 18 : 1 v7c (41.4 %), summed feature 3 (iso-C 15 : 0 2-OH and/or C 16 : 1 v7c; 18.5 %) and C 16 : 0 (10.9 %). Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain B2-9 T belonged to the genus Hydrocarboniphaga of the class Gammaproteobacteria and shared 97.0 % 16S rRNA gene sequence similarity with Hydrocarboniphaga effusa AP103 T . DNA-DNA relatedness between strain B2-9 T and H. effusa DSM 16095 T was 24 %. The DNA G+C content of strain B2-9 T was 66 mol%. Strain B2-9 T is considered to represent a novel species of the genus Hydrocarboniphaga, for which the name Hydrocarboniphaga daqingensis sp. nov. is proposed. The type strain is B2-9 T (5CGMCC