- Volume 55, Issue 2, 2005

A marine bacterial strain, designated FR1050T, was isolated from a sediment sample of getbol (Korean tidal flat). Phylogenetic investigations based on 16S rRNA gene sequence analysis showed that the isolate formed a robust monophyletic clade with Hahella chejuensis within the γ-Proteobacteria. Sequence similarity between strain FR1050T and the type strain of Hahella chejuensis was 94·7 %. Cells were Gram-negative, aerobic, rod-shaped, motile and halophilic; optimum growth occurred at sea salt concentrations of 4–6 %. The major fatty acids were C18 : 1 ω9c (39·0 %) and C16 : 0 (18·1 %). The DNA G+C content was 44 mol%. The polyphasic data obtained showed that strain FR1050T is affiliated to the genus Hahella but represents a novel species for which the name Hahella ganghwensis sp. nov. is proposed. The type strain is FR1050T (=KCTC 12277T=JCM 12486T).

Twenty Gram-negative, rod-shaped, slightly curved, non-spore-forming bacteria that gave a negative result in Arcobacter species-specific PCR tests but that yielded an amplicon in an Arcobacter genus-specific PCR test were isolated from 13 unrelated broiler carcasses. Numerical analysis of the profiles obtained by SDS-PAGE of whole-cell proteins clustered all isolates in a single group distinct from the other Arcobacter species. DNA–DNA hybridization among four representative strains exhibited DNA binding values above 91 %. DNA–DNA hybridization with reference strains of the current four Arcobacter species revealed binding levels below 47 %. The G+C contents ranged between 26·8 and 27·3 mol%. Pairwise comparison of 16S rRNA gene sequences revealed the mean values for similarity to the type strain of Arcobacter cryaerophilus (97·5 %), Arcobacter butzleri (96·5 %), Arcobacter skirrowii (96·0 %) and Arcobacter nitrofigilis (95·0 %). The levels of similarity to Campylobacter and Helicobacter species were below 88 and 87 %, respectively. The isolates could be distinguished from other Arcobacter species by the following biochemical tests: catalase, oxidase and urease activities; reduction of nitrate; growth at 25 and 37 °C under aerobic conditions; growth on 2–4 % (w/v) NaCl media; and susceptibility to cephalothin. These data demonstrate that the 20 isolates represent a single novel Arcobacter species, for which the name Arcobacter cibarius sp. nov. is proposed, with LMG 21996T (=CCUG 48482T) as the type strain.

Three strains isolated from the soil of a garden in Tokyo, Japan, were characterized physiologically, biochemically and in terms of fatty acid profile, DNA–DNA relatedness and 16S rRNA gene sequence. The isolates were Gram-negative, aerobic, rod-shaped cells with polar flagellation. According to DNA–DNA similarity, the strains belonged to the same species. The bacteria grew at temperatures from 10 to 37 °C, with an optimum around 25–30 °C. Growth was observed at pH values from 5·6 to 8·0. The DNA G+C content ranged from 63·4 to 64·0 mol%. Phylogenetic analyses of 16S rRNA gene sequences revealed a clear affiliation with members of the family ‘Xanthomonadaceae’. The closest relationship was seen with Fulvimonas soli and Frateuria aurantia, but, in terms of physiology and fatty acid profile, the bacteria described were rather distant from Fulvimonas and Frateuria. On the basis of phenotypic and phylogenetic distinctness, it is proposed that the isolates represent a novel species in a novel genus, namely Dyella japonica gen. nov., sp. nov. The type strain is XD53T (=IAM 15069T=DSM 16301T=ATCC BAA-939T).

Twelve strains of psychrophilic bacteria were isolated from cyanobacterial mat samples collected from various water bodies in the McMurdo Dry Valley region of Antarctica. All the isolates were Gram-negative, non-motile, coccoid, psychrophilic, halotolerant bacteria and had C16 : 1 ω7c, C17 : 1 ω8c and C18 : 1 ω9c as the major fatty acids, ubiquinone-8 as the respiratory quinone and DNA G+C content of 41–46 mol%. Based on these characteristics, the isolates were assigned to the genus Psychrobacter. Based on their SDS-PAGE profiles, the 12 isolates could be categorized into three groups. Six isolates of Group I were identified as representing strains of Psychrobacter okhotskensis. However, using detailed phenotypic and chemotaxonomic characteristics and phylogenetic analysis based on their 16S rRNA gene sequences, strain CMS 39T, the only strain from Group II, and strain CMS 56T, a representative strain of Group III, were different from each other and from all recognized species of Psychrobacter. Therefore, it is proposed to classify CMS 39T (=DSM 15337T=MTCC 4208T) and CMS 56T (=DSM 15339T=MTCC 4386T) as representing the type strains of novel species of Psychrobacter, for which the names Psychrobacter vallis sp. nov. and Psychrobacter aquaticus sp. nov., respectively, are proposed.

A thermophilic, anaerobic, chemolithoautotrophic bacterium, designated strain TB-2T, was isolated from the walls of an active deep-sea hydrothermal vent chimney on the Mid-Atlantic Ridge at 36° 14′ N 33° 54′ W. The cells were Gram-negative rods approximately 1·5 μm in length and 0·75 μm in width. Strain TB-2T grew between 45 and 70 °C (optimum 55 °C), 10 and 40 g NaCl l−1 (optimum 30 g l−1) and pH 4·5 and 7·5 (optimum pH 5·5). Generation time under optimal conditions was 50 min. Growth occurred under chemolithoautotrophic conditions with H2 as the energy source and CO2 as the carbon source. Nitrate or sulfur was used as the electron acceptor, with resulting production of ammonium and hydrogen sulfide, respectively. Oxygen, thiosulfate, sulfite, selenate and arsenate were not used as electron acceptors. Growth was inhibited by the presence of acetate, lactate, formate and peptone. The G+C content of the genomic DNA was 25·6 mol%. Phylogenetic analysis of the 16S rRNA gene sequence indicated that this organism is closely related to Caminibacter hydrogeniphilus and Caminibacter profundus (95·9 and 96·3 % similarity, respectively). On the basis of phylogenetic, physiological and genetic considerations, it is proposed that the organism represents a novel species within the genus Caminibacter, Caminibacter mediatlanticus sp. nov. The type strain is TB-2T (=DSM 16658T=JCM 12641T).

Two psychrophilic, chemolithoautotrophic, sulfur-oxidizing bacteria were isolated from marine Arctic sediments sampled off the coast of Svalbard with thiosulfate as the electron donor and CO2 as carbon source. Comparative analysis of 16S rRNA gene sequences suggested that the novel strains, designated SVAL-DT and SVAL-ET, represent members of the genus Thiomicrospira. Further genotypic (DNA–DNA relatedness, DNA G+C content) and phenotypic characterization revealed that the strains represent members of two novel species. Both organisms are obligately autotrophic and strictly aerobic. Nitrate was not used as an electron acceptor. Chemolithoautotrophic growth was observed with thiosulfate, tetrathionate and sulfur. The temperature limits for growth of both strains were between −2 °C and 20·8 °C, with optima of 11·5–13·2 °C (SVAL-ET) and 14·6–15·4 °C (SVAL-DT), which is about 13–15 °C lower than the optima of all other recognized Thiomicrospira species. The maximum growth rate on thiosulfate at 14 °C was 0·14 h−1 for strain SVAL-ET and 0·2 h−1 for strain SVAL-DT. Major fatty acids of SVAL-DT are C16 : 1, C18 : 0 and C16 : 0, and those of SVAL-ET are C16 : 1, C18 : 1, C16 : 0 and C14 : 1. Cells of SVAL-DT and SVAL-ET are rods, like those of their closest relatives. To our knowledge the novel strains are the first psychrophilic, chemolithoautotrophic, sulfur-oxidizing bacteria so far described. The names Thiomicrospira arctica sp. nov. and Thiomicrospira psychrophila sp. nov. are proposed for SVAL-ET (=ATCC 700955T=DSM 13458T) and SVAL-DT (=ATCC 700954T=DSM 13453T), respectively.

Gram-negative, non-spore-forming, rod-shaped bacteria, T7-09T and TR6-08T, were isolated from soil from a ginseng field in South Korea and characterized to determine their taxonomic position. 16S rRNA gene sequence analysis showed that the two isolates shared 99·5 % sequence similarity. Strains T7-09T and TR6-08T were shown to belong to the Proteobacteria and showed the highest levels of sequence similarity to Pseudoxanthomonas broegbernensis DSM 12573T (98·1 %), Pseudoxanthomonas mexicana AMX 26BT (97·4–97·5 %), Pseudoxanthomonas japonensis 12-3T (96·5–96·6 %), Pseudoxanthomonas taiwanensis ATCC BAA-404T (95·7 %) and Xanthomonas campestris ATCC 33913T (96·3–96·5 %). The sequence similarity values with respect to any species with validly published names in related genera were less than 96·5 %. The detection of a quinone system with Q-8 as the predominant compound and a fatty acid profile with C15 : 0 iso as the predominant acid supported the assignment of the novel isolates to the order ‘Xanthomonadales’. The two isolates could be distinguished from the established species of the genus Pseudoxanthomonas by the presence of quantitative unsaturated fatty acid C17 : 1 iso ω9c and by their unique biochemical profiles. The results of DNA–DNA hybridization clearly demonstrated that T7-09T and TR6-08T represent separate species. On the basis of these data, it is proposed that T7-09T (=KCTC 12208T=IAM 15116T) and TR6-08T (=KCTC 12207T=IAM 15115T) be classified as the type strains of two novel Pseudoxanthomonas species, for which the names Pseudoxanthomonas koreensis sp. nov. and Pseudoxanthomonas daejeonensis sp. nov., respectively, are proposed.

Yersinia kristensenii consists of phenotypically heterogeneous strains. This is reflected by the existence of strains with various multilocus enzyme electrophoresis and 16S rRNA gene sequence types. Strains originally phenotyped as members of Y. kristensenii were studied using 16S rRNA gene sequencing, DNA–DNA hybridization, determination of the DNA base composition and various phenotypic tests. The results were compared to those of Yersinia type strains. Based on levels of DNA–DNA relatedness, a specific 16S rRNA gene sequence type and the presence of lysine decarboxylase activity, a novel species, Yersinia aleksiciae sp. nov., is proposed. The type strain is Y159T (=WA758T=DSM 14987T=LMG 22254T).

The genus Methylovorus, currently represented by the restricted facultative methylotroph Methylovorus glucosotrophus Govorukhina and Trotsenko 1991 and the obligate methylotroph Methylovorus mays Doronina et al. 2001 , is here established by direct sequencing of amplified 16S rRNA genes and DNA–DNA hybridization to be clearly separated from the extant ribulose monophosphate (RuMP) pathway methylobacteria and to form a distinct branch within the β-Proteobacteria.

Six new Vibrio-like isolates originating from different species of bleached and healthy corals around Magnetic Island (Australia) were investigated using a polyphasic approach. Phylogenetic analyses based on 16S rRNA, recA and rpoA gene sequences split the isolates in two new groups. Strains LMG 22223T, LMG 22224, LMG 22225, LMG 22226 and LMG 22227 were phylogenetic neighbours of Photobacterium leiognathi LMG 4228T (95·6 % 16S rRNA gene sequence similarity), whereas strain LMG 22228T was related to Enterovibrio norvegicus LMG 19839T (95·5 % 16S rRNA gene sequence similarity). The two new groups can be distinguished from closely related species on the basis of several phenotypic features, including fermentation of d-mannitol, melibiose and sucrose, and utilization of different compounds as carbon sources, arginine dihydrolase activity, nitrate reduction, resistance to the vibriostatic agent O/129 and the presence of fatty acids 15 : 0 iso and 17 : 0 iso. The names Photobacterium rosenbergii sp. nov. (type strain LMG 22223T=CBMAI 622T=CC1T) and Enterovibrio coralii sp. nov. (type strain LMG 22228T=CBMAI 623T=CC17T) are proposed to accommodate these new isolates. The G+C contents of the DNA of the two type strains are respectively 47·6 and 48·2 mol%.

Two Gram-negative, non-fermentative, non-denitrifying, non-pigmented, rod-shaped bacteria that were motile by means of polar flagella, designated strains KMM 330T and KMM 331, were isolated from a deep-sea sponge specimen and subjected to a polyphasic taxonomic study. The new isolates exhibited 16S rRNA gene sequence similarity of 99·9 %, and their mean level of DNA–DNA relatedness was 82 %. Phylogenetic analysis based on their 16S rRNA gene sequences placed the strains within the genus Pseudomonas as an independent deep clade. Strain KMM 330T shared highest sequence similarity (96·3 %) with each of Pseudomonas fulva NRIC 0180T, Pseudomonas parafulva AJ 2129T and Pseudomonas luteola IAM 13000T; sequence similarity to other recognized species of the genus Pseudomonas was below 95·7 %. The marine sponge isolates KMM 330T and KMM 331 could be distinguished from the other recognized Pseudomonas species based on a unique combination of their phenotypic characteristics, including growth in 8 or 10 % NaCl, the absence of pigments, the inability to denitrify and lack of carbohydrate utilization. On the basis of phylogenetic analysis, physiological and biochemical characterization, strains KMM 330T and KMM 331 should be classified as a novel species of the genus Pseudomonas, for which the name Pseudomonas pachastrellae sp. nov. is proposed. The type strain is KMM 330T (=JCM 12285T=NRIC 0583T=CCUG 46540T).

Two novel denitrifying bacteria, designated strains MI55-1T and E9I37-1T, were isolated from deep-sea hydrothermal vent chimney structures at the Iheya North hydrothermal field in the Mid-Okinawa Trough, Japan. Both isolates were strict chemolithoautotrophs growing by respiratory nitrate reduction with H2, forming N2 as a metabolic product. Oxygen (at low concentrations) could serve as an alternative electron acceptor for growth of the isolates. Growth of strain MI55-1T was observed at temperatures between 40 and 57 °C (optimum, 55 °C; doubling time, 2 h), at pH values between 5·4 and 6·9 (optimum, pH 6·4) and in the presence of between 1·5 and 4·0 % (w/v) NaCl (optimum, 2·5 %). Growth of strain E9I37-1T was observed at temperatures between 28 and 40 °C (optimum, 37 °C; doubling time, 2·5 h), at pH values between 5·6 and 7·6 (optimum, pH 7·0) and in the presence of between 1·5 and 3·5 % (w/v) NaCl (optimum, 3·0 %). The G+C contents of the genomic DNA of strains MI55-1T and E9I37-1T were 29·6 and 35·5 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains MI55-1T and E9I37-1T belonged to groups A and F of the ε-Proteobacteria, but that they had distant phylogenetic relationships with any species, within the phylogenetic groups, that had validly published names (sequence similarities were less than 91 %). On the basis of the physiological and molecular characteristics of the novel isolates, it is proposed that they should each be classified in a novel genus: Nitratiruptor tergarcus gen. nov., sp. nov., with MI55-1T (=JCM 12459T=DSM 16512T) as the type strain, and Nitratifractor salsuginis gen. nov., sp. nov., with E9I37-1T (=JCM 12458T=DSM 16511T) as the type strain.

A bacterial strain was isolated from the water of Lake Martel in Mallorca (Spain). The isolate, designated MACL11T, was halotolerant and strictly aerobic. The cells were non-motile, non-spore-forming, Gram-negative short rods. Comparative 16S rRNA gene sequence analysis revealed that MACL11T represents a separate line of descent within the order ‘Rhizobiales’ of the class ‘Alphaproteobacteria’. Strain MACL11T was most closely related to the genera Rhizobium (93·3 % sequence similarity to Rhizobium rhizogenes), Aurantimonas (90·3 % sequence similarity to Aurantimonas coralicida) and Fulvimarina (90·3 % sequence similarity to Fulvimarina pelagi). Chemotaxonomically, strain MACL11T was characterized by the presence of Q-10 as the major respiratory lipoquinone. The major fatty acids detected were C19 : 0 cycloω8c, C18 : 1 ω7c, C16 : 0 and 11-methyl C18 : 1 ω7c. The G+C content of the DNA was 57·4 mol%. Oxidase and catalase activities were present. Growth with many different carbohydrates as the sole carbon source was observed. The data from this polyphasic study suggest that this bacterium belongs to a novel genus of the order ‘Rhizobiales’ and is not associated with any of the known families of this order. It is proposed that isolate MACL11T should be classified in a novel genus and species, Martelella mediterranea gen. nov., sp. nov., with MACL11T (=LMG 22193T=CECT 5861T) as the type strain.

Phylogenetic analysis of 16S rRNA gene sequences revealed that Enterococcus solitarius is not a member of the genus Enterococcus, but is related to species of the genus Tetragenococcus. On a phylogenetic tree, E. solitarius clustered with Tetragenococcus halophilus and Tetragenococcus muriaticus, with which it showed the highest 16S rRNA gene sequence similarity level (about 94 %). Phenotypic studies indicated that E. solitarius was also unable to produce acid from lactose, providing further evidence of its affiliation to the genus Tetragenococcus. DNA hybridization studies indicated that E. solitarius was clearly a separate species, different from T. halophilus and T. muriaticus (reassociation levels of about 23 and 54 %, respectively). As suggested in previous studies, E. solitarius is closely related to but clearly distinct from T. halophilus. Based upon properties that taxonomically distinguish it from species of the genus Enterococcus, it is proposed that E. solitarius be transferred to the genus Tetragenococcus and reclassified as Tetragenococcus solitarius comb. nov. (type strain, 885/78T=ATCC 49428T=CCUG 29293T=CIP 103330T=DSM 5634T=JCM 8736T=LMG 12890T=NCTC 12193T).

An actinomycete strain (CB1190T) was previously isolated from industrial sludge contaminated with 1,4-dioxane. The cells of this culture are Gram-positive and exhibit branching aerial and vegetative mycelium. Analysis of the 16S rRNA gene sequence indicates that the strain belongs to the genus Pseudonocardia, closely related to Pseudonocardia hydrocarbonoxydans, P. sulfidoxydans and P. halophobica. Physiological and biochemical characteristics of CB1190T are different from those of other known Pseudonocardia species. The novel organism described here is distinguished by its ability to grow on 1,4-dioxane, which is a probable human carcinogen. This culture can also grow on tetrahydrofuran, gasoline aromatics and several other toxic environmental contaminants. Strain CB1190T is capable of fixing dinitrogen. The predominant fatty acids are 16 : 0 iso, 16 : 1 iso cis9 and 17 : 1 iso cis9. The major phospholipid fatty acids are 16 : 0 iso, 16 : 0 10-Me and 17 : 0 10-Me. The peptidoglycan belongs to type A1γ, meso-diaminopimelic acid. The major menaquinone is MK-8 (H4). Mycolic acids are absent. The G+C content is 74 mol%. Based on morphological, physiological, chemotaxonomic and phylogenetic evidence, it is proposed that strain CB1190T (=ATCC 55486T=DSM 44775T) be classified as the type strain of a novel species, Pseudonocardia dioxanivorans sp. nov. Further studies with this organism will provide insights into metabolic pathways, responsible enzymes, kinetics and the fate of 1,4-dioxane in the environment.

Three heterofermentative lactic acid bacteria, obtained from Greek and Belgian artisanal wheat sourdoughs, were preliminarily identified as Lactobacillus brevis-like after screening using whole-cell protein fingerprinting and 16S rRNA gene sequence analysis. The three sourdough isolates showed nearly identical sequences (>99·7 % sequence similarity), and highest similarities of 98·2 and 97·6 % were obtained to the species Lactobacillus spicheri and Lactobacillus brevis, respectively. Growth characteristics, biochemical features, amplified fragment length polymorphism fingerprinting, DNA–DNA hybridizations and DNA G+C contents demonstrated that the isolates represent two novel Lactobacillus species. The names Lactobacillus acidifarinae sp. nov. and Lactobacillus zymae sp. nov. are proposed and the type strains are LMG 22200T (=R-19065T=CCM 7240T) and LMG 22198T (=R-18615T=CCM 7241T), respectively.

A taxonomic study of two crude-oil-degrading, Gram-positive bacterial strains, designated BAS69T and BNP48T, revealed that they represent two novel Microbacterium species. 16S rRNA gene sequence similarity to their closest phylogenetic neighbours was 98·5 % for BAS69T (Microbacterium paraoxydans DSM 15019T and Microbacterium saperdae DSM 20169T) and 99 % for BNP48T (Microbacterium luteolum DSM 20143T). Levels of DNA–DNA relatedness to the closest phylogenetic neighbours of both strains were between 11 and 38 %. According to phylogenetic analysis, the two strains are distinguishable from all recognized species of Microbacterium. Morphological and physiological characteristics of strains BAS69T and BNP48T were different from those of phylogenetically closely related Microbacterium species. The diamino acid in the cell-wall peptidoglycan of BAS69T is lysine and of BNP48T is ornithine. The major menaquinones are MK-11 and MK-12 for both strains. Based on their ability to degrade crude oil, the name Microbacterium oleivorans sp. nov. is proposed for strain BAS69T (=DSM 16091T=NCIMB 14003T) and Microbacterium hydrocarbonoxydans is proposed for strain BNP48T (=DSM 16089T=NCIMB 14002T).

A rod-shaped, Gram-positive bacterium, strain TNJL143-2T, having N-acyl-d-amino acid amidohydrolase (d-aminoacylase) activity, was isolated from a soil sample from Natori, Japan. It was a non-spore-forming, strictly aerobic bacterium without motility, showing a temperature optimum for growth of 30 °C and a pH optimum for growth of 5–7. The 16S rRNA gene sequence of the strain showed the highest similarities to members of the genus Microbacterium, in particular, Microbacterium aerolatum, Microbacterium foliorum and Microbacterium phyllosphaerae. The chemotaxonomic characteristics, including the compositions of cellular menaquinones, cellular fatty acids and cell-wall amino acids, were consistent with those described for the genus Microbacterium. The G+C content of the genomic DNA was determined as 69·1 mol%. DNA–DNA hybridization studies using type strains of M. aerolatum, M. foliorum and M. phyllosphaerae showed only low levels of relatedness (11–12 %). On the basis of these phenotypic and genotypic results, a novel species, Microbacterium natoriense sp. nov., is proposed, with TNJL143-2T (=JCM 12611T=ATCC BAA-1032T) as the type strain.

Dermatitis digitalis is an economically important ulcerative disease of undetermined aetiology affecting the hooves of cattle. Material was examined from two independent cases of this disease in Switzerland. Cultures from the advancing front of both lesions yielded large numbers of closely related short, mesophilic, non-motile, non-spore-forming, anaerobic, proteolytic, Gram-positive rods. The 16S rRNA gene sequences of strains OMZ 913T and OMZ 915 were identical and indicate Tindallia magadiensis and Eubacterium saphenum as their closest relatives. Phenotypically, the novel isolates are clearly distinguished from related bacteria by protein and antigen patterns, by cellular fatty acids and by API ZYM activities. The diamino acid of the Gram-positive cell wall is ornithine and the G+C content of OMZ 913T DNA is 44·4 mol%. The phylogenetic distance from recognized taxa in the phylum Firmicutes is sufficient to place these bovine isolates into a novel genus and species, for which the name Guggenheimella bovis gen. nov., sp. nov. is proposed, with OMZ 913T (=CIP 108087T=DSM 15657T) as the type strain.