- Volume 55, Issue 4, 2005

Analysis of the G+C content, DNA–DNA relatedness to other leptospires and 16S rRNA gene sequence of Leptospira parva showed that this species was not related to other Leptospira species. On the basis of these data, it is proposed that Leptospira parva should be transferred to the genus Turneriella as Turneriella parva gen. nov., comb. nov., with strain HT (=NCTC 11395T=ATCC BAA-1111T) as the type strain.

Eleven strains of anaerobic Gram-negative bacilli isolated from the human oral cavity were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise two homogeneous groups, designated E2 and E4. 16S rRNA gene sequence analysis revealed that members of both groups belonged to the genus Prevotella but were distinct from any species with validly published names. This distinction was confirmed by DNA–DNA hybridization and phenotypic tests. Two novel species are therefore proposed: Prevotella marshii sp. nov. (group E2) and Prevotella baroniae (group E4). Both species are saccharolytic; the end-products of fermentation for P. marshii are acetic, propionic and succinic acids, while P. baroniae produces acetic and succinic acids with minor amounts of isovaleric and isobutyric acids. The G+C content of the DNA of the type strain of Prevotella marshii is 51 mol% and that of Prevotella baroniae is 52 mol%. The type strain for P. marshii is E9.34T (=DSM 16973T=CCUG 50419T) and that for P. baroniae is E9.33T (=DSM 16972T=CCUG 50418T).

A Gram-negative, aerobic, gliding, orange–yellow marine bacterium was isolated from particulate material sampled from the Southern Ocean. This strain produced an exopolysaccharide in liquid culture. 16S rRNA gene sequence analysis showed that this isolate was a member of the family Flavobacteriaceae, but represented a separate lineage. Major whole-cell fatty acids included i15 : 1ω10c, i15 : 0, β-OH i15 : 0, a15 : 1ω10c, 15 : 0 and α-OH i15 : 0. The G+C content of the DNA was 49 mol%. Based on phylogenetic, phenotypic, chemotaxonomic and genotypic analyses, this bacterium was placed in a novel taxon as Olleya marilimosa gen. nov., sp. nov. with type strain CAM030T (=ACAM 1065T=CIP 108537T).

Bacteria called ‘Fritschea’ are endosymbionts of the plant-feeding whitefly Bemisia tabaci and scale insect Eriococcus spurius. In the gut of B. tabaci, these bacteria live within bacteriocyte cells that are transmitted directly from the parent to oocytes. Whiteflies cause serious economic damage to many agricultural crops; B. tabaci fecundity and host range are less than those of Bemisia argentifolii, possibly due to the presence of this endosymbiont. The B. tabaci endosymbiont has been characterized using electron microscopy and DNA analysis but has not been isolated or propagated outside of insects. The present study compared sequences for 11 endosymbiont genes to genomic data for chlamydial families Parachlamydiaceae, Chlamydiaceae and Simkaniaceae and to 16S rRNA gene signature sequences from 330 chlamydiae. We concluded that it was appropriate to propose ‘Candidatus Fritschea bemisiae’ strain Falk and ‘Candidatus Fritschea eriococci’ strain Elm as members of the family Simkaniaceae in the Chlamydiales.

A Gram-negative, rod-shaped bacterium (designated strain UST030701-295T) with fast gliding motility was isolated from the surface of the sponge Lissodendoryx isodictyalis in the Bahamas. Colonies of UST030701-295T were yellow in colour, 2–4 mm in diameter, convex with a smooth surface and entire margins. UST030701-295T was heterotrophic, strictly aerobic and required NaCl for growth (1·0–4·0 %). Growth was observed at pH 6·0–10·0 and at 12–44 °C. Phylogenetic analysis of the 16S rRNA gene sequence placed UST030701-295T within the genus Winogradskyella of the family Flavobacteriaceae, sharing 94·7–95·8 % similarity with the three recognized members of the genus. The G+C content of the DNA was 32·8 mol% and the predominant fatty acids were iso-C15 : 1, iso-C15 : 0, iso-C15 : 0 2-OH, iso-C15 : 0 3-OH, iso-C16 : 0 3-OH, C16 : 1 ω7 and iso-C17 : 0 3-OH (together representing 75·4 % of the total); these data supported the affiliation of UST030701-295T to the genus Winogradskyella. UST030701-295T differed from the three recognized species of Winogradskyella in 7–17 traits. Molecular evidence together with phenotypic characteristics suggests that UST030701-295T represents a novel species within the genus Winogradskyella, for which the name Winogradskyella poriferorum sp. nov. is proposed. The type strain is UST030701-295T (=NRRL B-41101T=JCM 12885T).

Two Gram-negative, rod-shaped, non-motile bacterial strains, MSS-170T and MSS-171, were isolated from sea water of a marine solar saltern of the Yellow Sea, Korea, and characterized by using a polyphasic taxonomic approach. The two isolates grew optimally at 30 °C and in the presence of 2 % (w/v) NaCl. They were characterized chemotaxonomically as having MK-7 as the predominant menaquinone and major amounts of fatty acids iso-C15 : 0 and C16 : 1 ω7c and/or iso-C15 : 0 2-OH. The DNA G+C content of each of the two strains was 42 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that the two strains fall within the evolutionary radiation enclosed by the genus Algoriphagus. Strains MSS-170T and MSS-171 had identical 16S rRNA gene sequences and exhibited a mean DNA–DNA relatedness level of 93 %. The two strains exhibited 16S rRNA gene sequence similarity levels of 96·4–98·9 % with respect to the type strains of recognized Algoriphagus species. DNA–DNA relatedness levels between the two strains and the type strains of six Algoriphagus species were less than 35 %. On the basis of phenotypic data and phylogenetic and genetic distinctiveness, strains MSS-170T and MSS-171 were classified in the genus Algoriphagus as members of a novel species, for which the name Algoriphagus locisalis sp. nov. is proposed. The type strain is MSS-170T (=KCTC 12310T=JCM 12597T).

Limit-dilution procedures were used to isolate seven, helically coiled bacterial strains from faeces of swine that constituted two unidentified taxa. Comparative 16S rRNA gene sequence analysis showed highest similarity values with species of the genus Treponema indicating that the isolates are members of this genus. Strain 7CPL208T, as well as five further isolates, and 14V28T displayed the highest 16S rRNA gene sequence similarities with Treponema pectinovorum ATCC 33768T (92·3 %) and Treponema parvum OMZ 833T (89·9 %), respectively. Polar lipid profiles distinguished 7CPL208T and 14V28T from each other as well as from related species. Based on their phenotypic and genotypic distinctiveness, strains 7CPL208T and 14V28T are suggested to represent two novel species of the genus Treponema, for which the names Treponema berlinense sp. nov. and Treponema porcinum sp. nov. are proposed. The type strain for Treponema berlinense is 7CPL208T (=ATCC BAA-909T=CIP 108244T=JCM 12341T) and for Treponema porcinum 14V28T (=ATCC BAA-908T=CIP 108245T=JCM 12342T).

A collection of 75 strains of Pectobacterium chrysanthemi (including all biovars and pathovars) and the type strains of Brenneria paradisiaca (CFBP 4178T) and Pectobacterium cypripedii (CFBP 3613T) were studied by DNA–DNA hybridization, numerical taxonomy of 121 phenotypic characteristics, serology and 16S rRNA gene-based phylogenetic analyses. From analysis of 16S rRNA gene sequences, it was deduced that P. chrysanthemi strains and B. paradisiaca CFBP 4178T formed a clade distinct from the genera Pectobacterium and Brenneria; therefore, it is proposed to transfer all the strains to a novel genus, Dickeya gen. nov. By DNA–DNA hybridization, the strains of P. chrysanthemi were distributed among six genomic species: genomospecies 1 harbouring 16 strains of biovar 3 and four strains of biovar 8, genomospecies 2 harbouring 16 strains of biovar 3, genomospecies 3 harbouring two strains of biovar 6 and five strains of biovar 5, genomospecies 4 harbouring five strains of biovar 2, genomospecies 5 harbouring six strains of biovar 1, four strains of biovar 7 and five strains of biovar 9 and genomospecies 6 harbouring five strains of biovar 4 and B. paradisiaca CFBP 4178T. Two strains of biovar 3 remained unclustered. Biochemical criteria, deduced from a numerical taxonomic study of phenotypic characteristics, and serological reactions allowed discrimination of the strains belonging to the six genomic species. Thus, it is proposed that the strains clustered in these six genomic species be assigned to the species Dickeya zeae sp. nov. (type strain CFBP 2052T=NCPPB 2538T), Dickeya dadantii sp. nov. (type strain CFBP 1269T=NCPPB 898T), Dickeya chrysanthemi comb. nov. (subdivided into two biovars, bv. chrysanthemi and bv. parthenii), Dickeya dieffenbachiae sp. nov. (type strain CFBP 2051T=NCPPB 2976T), Dickeya dianthicola sp. nov. (type strain CFBP 1200T=NCPPB 453T) and Dickeya paradisiaca comb. nov., respectively.

Strain GR3T was isolated from drinking water during a screening programme to monitor the bacterial population present in the distribution system of Seville (Spain), and it was studied phenotypically, genotypically and phylogenetically. This pink-pigmented bacterium was identified as a Methylobacterium sp. Members of this genus are distributed in a wide variety of natural habitats, including soil, dust, air, freshwater and aquatic sediments. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain GR3T was closely related to Methylobacterium aquaticum (97·4 % sequence similarity), whereas sequence similarity values with respect to the rest of the species belonging to this genus were lower than 96 %. Furthermore, the DNA–DNA hybridization data and its phenotypic characteristics clearly indicate that the isolate represents a novel Methylobacterium species, for which the name Methylobacterium variabile sp. nov. is proposed. GR3T (=DSM 16961T=CCM 7281T=CECT 7045T) is the type strain; the DNA G+C content of this strain is 69·2 mol%.

The taxonomic position of the free-living diazotrophic strain COC8T isolated from rice was investigated based on phylogenetic analyses. 16S rRNA gene sequence analyses indicated that strain COC8T was closely related to the genus Azospirillum (96 % similarity). Chemotaxonomic characteristics (G+C content of the DNA 66·8 mol%, Q-10 quinone system, 18 : 1ω7c as the major fatty acid and 14 : 0 3-OH and 16 : 0 3-OH as the major hydroxy fatty acids) were also similar to those of the genus Azospirillum. Based on its physiological characteristics, strain COC8T can clearly be differentiated from recognized species of Azospirillum. The name Azospirillum oryzae sp. nov. is proposed to accommodate this bacterial strain; the type strain is COC8T (=IAM 15130T=CCTCC AB204051T).

A psychrotolerant, Gram-negative, motile bacterium, designated CK 47T, was isolated from sea water off the subantarctic Kerguelen islands (50° 40′ S 68° 25′ E). The isolate grew optimally at 22 °C and minimum and maximum temperature of growth were 4 and 37 °C, respectively. It required Na+ for growth and exhibited optimum growth at pH 8·5 and 4 % NaCl. It utilized hexane, heptane and petroleum ether as sole sources of carbon. Strain CK 47T had Q9 as the major respiratory quinone and C16 : 0 (21·7 %), C17 : 0 (21·3 %), C18 : 0 (5·7 %), C18 : 1 ω7c (9·0 %) and C18 : 1 ω9c (31·4 %) as predominant fatty acids. The G+C content of the DNA was 58 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that CK 47T formed a coherent cluster within the genus Marinobacter. It exhibited highest 16S rRNA gene sequence similarity of 96·8 % with Marinobacter lipolyticus. However, the level of DNA–DNA relatedness between strain CK47T and M. lipolyticus was only 55 %. On the basis of phenotypic characteristics, and phylogenetic and genotypic distinctiveness, strain CK 47T is considered to represent a novel species of the genus Marinobacter. The name Marinobacter maritimus sp. nov. is proposed, with CK 47T (=JCM 12521T=MTCC 6519T) as the type strain.

Two strains were isolated from tuff, a volcanic rock that forms the walls of the Roman Catacombs of Saint Callixtus in Rome, Italy. A polyphasic approach using nutritional and physiological tests, reactions to antibiotics, fatty acid profiles, DNA base ratios, DNA–DNA reassociation and 16S rRNA gene sequence comparisons showed that the two isolates belong to a novel species within the genus Phyllobacterium. The species Phyllobacterium catacumbae sp. nov. is proposed. The type strain is CSC19T (=CECT 5680T=LMG 22520T).

A bacterial strain designated GPTSA 20T, which was isolated from a warm spring in Assam, India, was characterized by using a polyphasic approach. The cells were Gram-negative, aerobic rods, which could not utilize or produce acid from most of the carbohydrates tested. The predominant fatty acids were C15 : 0 iso (25·04 %), C17 : 1 iso ω9c (19·28 %), C16 : 0 iso (17·73 %) and C11 : 0 iso 3-OH (9·34 %). The G+C content was 75 mol%. From 16S rRNA gene sequence analysis (1433 nucleotides, continuous stretch), it was confirmed that strain GPTSA 20T belonged to the class ‘Gammaproteobacteria’. The closest 16S rRNA gene sequence similarity found (98·2 %) was with an uncultured bacterium clone, NB-03 (accession no. AB117707), from an autotrophic nitrifying biofilm. Among culturable bacteria, the closest sequence similarities were with Fulvimonas soli (93·0 %), Silanimonas lenta (92·8 %), Thermomonas hydrothermalis (92·4 %), Frateuria aurantia (91·9 %), Rhodanobacter lindaniclasticus (91·9 %), Thermomonas haemolytica (91·9 %) and Pseudoxanthomonas taiwanensis (91·8 %); similarities of less than 91·8 % were obtained with other members of the class ‘Gammaproteobacteria’. From the biochemical, physiological, chemotaxonomic and phylogenetic analysis, it was clear that strain GPTSA 20T was quite different from members of known genera of the class ‘Gammaproteobacteria’. Therefore, it is proposed that strain GPTSA 20T represents a novel species within a new genus, with the name Aquimonas voraii gen. nov., sp. nov. The type strain is GPTSA 20T (=MTCC 6713T=JCM 12896T).

Previously, a psychrophilic rod-shaped marine bacterium (strain HAW-EB3T) isolated from Halifax Harbour sediment was noted for its ability to degrade hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). In the present study phenotypic, chemotaxonomic and genotypic characterization showed that strain HAW-EB3T represents a novel species of Shewanella. Strain HAW-EB3T contained lysine decarboxylase, which is absent in other known Shewanella species, and distinguished itself from most other species of Shewanella by the presence of arginine dehydrolase, ornithine decarboxylase and chitinase, and by its ability to oxidize and ferment N-acetyl-d-glucosamine. Strain HAW-EB3T grew on several carbon sources (N-acetyl-d-glucosamine, Tween 40, Tween 80, acetate, succinate, butyrate and serine) and showed distinctive fatty acid and quinone compositions. Both phenotypic and 16S rRNA gene phylogenetic cluster analyses demonstrated that HAW-EB3T belongs to the Na+-requiring group of Shewanella species. The HAW-EB3T 16S rRNA gene sequence displayed ⩽97·4 % similarity to all known Shewanella species and was most similar to those of two bioluminescent species, Shewanella hanedai and Shewanella woodyi. However, gyrB of strain HAW-EB3T was significantly different from those of other Shewanella species, with similarities less than 85 %. DNA-DNA hybridization showed that its genomic DNA was less than 25 % related to that of S. hanedai or S. woodyi. Therefore we propose Shewanella sediminis sp. nov., with HAW-EB3T (=NCIMB 14036T=DSM 17055T) as the type strain.

An α-proteobacterium has been identified which is believed to be the causative agent of juvenile oyster disease (JOD). Since its first isolation in 1997, the bacterium has been recovered as the numerically dominant species from JOD-affected animals throughout the north-eastern United States (Maine, New York and Massachusetts). Colonies are usually beige to pinkish-beige, although the majority of isolates recovered in 2003 from an epizootic in Martha's Vineyard, Massachusetts, produce colonies with a greenish-yellow appearance. The cells are Gram-negative, aerobic, strictly marine and rod or ovoid in appearance. They are actively motile by one or two flagella, but cells are also observed to produce tufts of polar fimbriae. The principal fatty acid in whole cells is C18 : 1 ω7c and other characteristic fatty acids are C16 : 0, C10 : 0 3-OH, 11-methyl C18 : 1 ω7c and C18 : 0. Almost without exception, isolates have 16S rRNA gene sequences that are 100 % identical to each other. Phylogenetic analyses place the organism within the Roseobacter clade of the α-Proteobacteria, with moderate bootstrap support for inclusion in the genus Roseovarius. DNA–DNA relatedness values from pairwise comparisons of this organism with the type species of the genus (Roseovarius tolerans) and the only other described species in this genus, Roseovarius nubinhibens, were 11 and 47 %, respectively. Phenotypic and biochemical dissimilarities also support the assignment of this bacterium to a novel species. The name Roseovarius crassostreae sp. nov. is proposed, with the type strain CV919-312T (=ATCC BAA-1102T=DSM 16950T).

A nitrogen-fixing bacterium, designated strain 6H33bT, was isolated from a compost pile in Japan. The nitrogenase activity of this strain was detected based on its acetylene-reducing activity under low oxygen concentrations (2–4 %). An analysis of the genes responsible for nitrogen fixation in this strain, nifH and nifD, indicated a close relationship to those of Pseudomonas stutzeri A15 (A1501). Sequence similarity searches based on the 16S rRNA gene sequences showed that strain 6H33bT belongs within the genus Pseudomonas sensu stricto; closest similarity was with Pseudomonas indica (97·3 %). A comparison of several taxonomic characteristics of 6H33bT with those of P. indica and some type strains of the genus Pseudomonas sensu stricto indicated that 6H33bT could be distinguished from P. indica based on the presence of nitrogen fixation ability, the absence of nitrate reduction and denitrification abilities and the utilization of some sugars and organic acids. Phylogenetic analyses and the results of DNA–DNA hybridization experiments also indicated that strain 6H33bT represents a species distinct from P. indica. From these results, it is proposed that strain 6H33bT (=ATCC BAA-1049T=JCM 12708T) is classified as the type strain of a novel species of the genus Pseudomonas sensu stricto under the name Pseudomonas azotifigens sp. nov.