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Two Gram-stain-negative, aerobic, non-motile bacteria, designated KMS-5 T and CYK-10 T , were isolated from freshwater environments. 16S rRNA gene sequence similarity results indicated that these two novel strains belong to the family Rhodobacteraceae . Strain KMS-5 T is closely related to species within the genus Tabrizicola (96.1-96.8 % sequence similarity) and Cypionkella (96.5-97.0 %). Strain CYK-10 T is closest to Rhodobacter thermarum YIM 73036 T with 96.6 % sequence similarity. Phylogenetic analyses based on 16S rRNA gene sequences and an up-to-date bacterial core gene set showed that strain KMS-5 T is affiliated with species in the genus Tabrizicola and strain CYK-10 T is placed in a distinct clade with Rhodobacter blasticus ATCC 33485 T , Rhodobacter thermarum YIM 73036 T and Rhodobacter flagellatus SYSU G03088 T . These two strains shared common chemotaxonomic features comprising Q-10 as the major quinone, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine as the principal polar lipids, and C 18 : 1  ω 7 c as the main fatty acid. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between these two novel isolates and their closest relatives were below the cut-off values of 95-96, 90 and 70 %, respectively, used for species demarcation. The obtained polyphasic taxonomic data suggested that strain KMS-5 T represents a novel species within the genus Tabrizicola , for which the name Tabrizicola oligotrophica sp. nov. is proposed with KMS-5 T (=BCRC 81196 T =LMG 31337 T ) as the type strain, and strain CYK-10 T should represent a novel species of the genus Rhodobacter , for which the name Rhodobacter tardus sp. nov. is proposed with CYK-10 T (=BCRC 81191 T =LMG 31336 T ) as the type strain.

Three strains (JA826T, JA912T and JA913), which were yellowish brown colour, rod to oval shaped, Gram-stain-negative, motile, phototrophic bacteria with a vesicular architecture of intracytoplasmic membranes, were isolated from different pond samples. The DNA G+C content of the three strains was between 64.6 and 65.5 mol%. The highest 16S rRNA gene sequence similarity of all three strains was with the type strains of the genus Rhodobacter sensu stricto in the family Rhodobacteraceae. Strain JA826T had highest sequence similarity with Rhodobacter maris JA276T (98.5 %), Rhodobacter viridis JA737T (97.5 %) and other members of the genus Rhodobacter (<97 %). Strain JA912T had highest sequence similarity with Rhodobacter viridis JA737T (99.6 %), Rhodobacter sediminis N1T (99.3 %), Rhodobacter capsulatus ATCC 11166T (98.8 %) and less than 97 % similarity with other members of the genus Rhodobacter. The 16S rRNA gene sequence similarity between strains JA826T and JA912T was 96.9 %. DNA-DNA hybridization showed that strains JA826T and JA912T (values among themselves and between the type strains of nearest members <44 %) did not belong to any of the nearest species of the genus Rhodobacter. However, strains JA912T and JA913 were closely related (DNA-DNA hybridization value >90 %). The genomic distinction was also supported by differences in phenotypic and chemotaxonomic characteristics in order to propose strains JA826T (=KCTC 15478T=LMG 28758T) and JA912T (=KCTC 15475T=LMG 28748T) as new species in the genus Rhodobacter sensu stricto with the names Rhodobacter lacus and Rhodobacter azollae, respectively.

A novel non-sporulating, non-motile, catalase- and oxidase-positive, strictly aerobic, Gram-negative, rod-shaped bacterial strain, designated DCA-1(T), was isolated from activated sludge collected from a butachlor wastewater treatment facility. The strain was able to degrade about 85 % of 100 mg butachlor l(-1) within 5 days of incubation. Growth occurred in the presence of 0-6 % (w/v) NaCl [optimum, 1 % (w/v) NaCl] and at pH 5.5-9.0 (optimum, pH 7.0) and 15-35 °C (optimum, 25-30 °C). Vesicular internal membrane structures and photoheterotrophic growth were not observed. The major respiratory quinone was ubiquinone 10 (Q-10) and the major cellular fatty acids were C(18 : 1)ω7c and 11-methyl C(18 : 1)ω7c. The genomic DNA G+C content of strain DCA-1(T) was 62.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that strain DCA-1(T) was a member of the family Rhodobacteraceae and was related most closely to the type strain of Catellibacterium aquatile (96.5 % sequence similarity). The combination of phylogenetic analysis, phenotypic characteristics and chemotaxonomic data supports the suggestion that strain DCA-1(T) represents a novel species of the genus Catellibacterium, for which the name Catellibacterium caeni sp. nov. is proposed. The type strain is DCA-1(T) ( = CGMCC 1.7745(T)  = DSM 21823(T)). In addition, based on the characterization data obtained in this study, it is proposed that Rhodobacter changlensis should be reclassified as Catellibacterium changlense comb. nov. (type strain JA139(T)  = DSM 18774(T)  = CCUG 53722(T)  = JCM 14338(T)). An emended description of the genus Catellibacterium is also presented.

Twelve strains of gram-negative, nonfermenting rods recovered mainly from septicemic patients were studied using conventional and molecular methods. The phenotypic profiles of these strains most closely resembled Psychrobacter phenylpyruvicus. They produced catalase, oxidase, urease, and H(2)S (lead acetate paper) but did not produce indole, reduce nitrate or nitrite, or hydrolyze gelatin or esculin. No acid production was observed in a King's oxidation-fermentation base containing d-glucose, d-xylose, d-mannitol, sucrose, lactose, or maltose. All strains were nonmotile and nonpigmented. Most strains produced green discoloration on blood agar. All strains grew at 25 degrees C and 35 degrees C and most grew on MacConkey agar. They shared a common cellular fatty acid (CFA) profile characterized by large amounts (56% to 90%) of 18:1omega7c and the presence of 3-OH-10:0, 16:1omega7c, 16:0, and 19:0cycomega8c that overall was most similar to that of Rhodobacter species but was quite distinct from that of P. phenylpyruvicus. The MICs for most beta-lactams, fluoroquinolones, aminoglycosides, and carbapenems were low. MICs for aztreonam and piperacillin were higher, with MICs for some strains of > 64 mg/liter and > 128 mg/liter, respectively. Polyphasic analysis of these strains, including morphological, biochemical, CFA composition, DNA-DNA hybridization, 16S rRNA gene sequencing, and percent guanine-plus-cytosine (G+C) content analysis, demonstrated that these strains and Rhodobacter massiliensis represent a new genus, "Haematobacter" (proposed name), with the species H. missouriensis (type strain H1892(T) = CCUG 52307(T) = CIP 109176(T)) and H. massiliensis comb. nov. (type strain Framboise(T) = CCUG 47968(T) = CIP 107725(T)) and an unnamed genomospecies.