Acetobacterium tundrae sp nov, a new psychrophilic acetogenic bacterium from tundra soil.

:A new psychrophilic, anaerobic, acetogenic bacterium from the tundra wetland soil of Polar Ural is described. The organism fermented H2/CO2, formate, methanol, and several sugars to acetate as the sole end-product. The temperature range for growth was 1-30 degrees C with an optimum at 20 degrees C. The bacterium showed no growth at 32 degrees C. Cells were gram-positive, oval-shaped, flagellated rods 0.7-1.l x 1.1-4.0 microm in size when grown at 1-20 degrees C. At 25-30 degrees C, the cell size increased up to 2-3 x 10-15 microm due to a defect in cell division. The DNA G+C content of the organism was 39.2 mol%. Based upon 16S rDNA analysis and DNA-DNA reassociation studies, the organism was classified in the genus Acetobacterium as a new species, for which the name Acetobacterium tundrae sp. nov. is proposed. The type strain is Z-4493 (=DSM 9173T).

Simankova MV ，Kotsyurbenko OR ，Stackebrandt E ，Kostrikina NA ，Lysenko AM ，Osipov GA ，Nozhevnikova AN ... -  《ARCHIVES OF MICROBIOLOGY》

Thermotalea metallivorans gen. nov., sp. nov., a thermophilic, anaerobic bacterium from the Great Artesian Basin of Australia aquifer.

A strictly anaerobic, thermophilic bacterium, designated strain B2-1(T), was isolated from microbial mats colonizing a runoff channel formed by free-flowing thermal water from a Great Artesian Basin, Australia, bore well (registered number 17263). The cells of strain B2-1(T) were slightly curved rods (3.0-3.5 x 0.6-0.7 microm) which stained Gram-negative. The strain grew optimally in tryptone-yeast extract-glucose medium at 50 degrees C (temperature growth range 30-55 degrees C) and a pH of 8 (pH growth range 6.5-9). Strain B2-1(T) grew poorly on yeast extract (0.2 %) and/or tryptone (0.2 %), which were obligately required for growth on other energy sources, including a range of other carbohydrates and organic acids, but not amino acids. The end-products of glucose fermentation were ethanol and acetate. In the presence of 0.2 % yeast extract, iron(III), manganese(IV) and elemental sulfur were reduced but sulfate, thiosulfate, sulfite, nitrate and nitrite were not reduced. Growth was inhibited by chloramphenicol, streptomycin, tetracycline, penicillin, ampicillin, sodium azide and by NaCl concentrations greater than 4 % (w/v). The DNA G+C content was 48+/-1 mol% as determined by the thermal denaturation method. 16S rRNA gene sequence analysis indicated that strain B2-1(T) was a member of the family Clostridiaceae, class Clostridia, phylum Firmicutes and was most closely related to Geosporobacter subterraneus DSM 17957(T) (89.9 % similarity). On the basis of 16S rRNA gene sequence comparisons and physiological characteristics, strain B2-1(T) is considered to represent a novel species of a new genus, for which the name Thermotalea metallivorans gen. nov., sp. nov. is proposed. The type strain is B2-1(T) (=KCTC 5625(T)=JCM 15105(T)=DSM 21119(T)).

Ogg CD ，Patel BK 《international journal of systematic and evolutionary microbiology》

Description of Mogibacterium pumilum gen. nov., sp. nov. and Mogibacterium vescum gen. nov., sp. nov., and reclassification of Eubacterium timidum (Holdeman et al. 1980) as Mogibacterium timidum gen. nov., comb. nov.

A new genus, Mogibacterium, is proposed for anaerobic, non-spore-forming, Gram-positive, rod-shaped bacteria which have been isolated from the periodontal pockets of adult human patients with periodontal disease and infected root canals. The novel isolates, strains D2-18T, BA11a-f and D5-2T, were inert in most of the conventional biochemical tests and phenotypically resemble asaccharolytic Eubacterium species. The protein profiles of whole cells on SDS-PAGE gels and Western immunoblotting reaction analysis distinguished these organisms from type strains belonging to the previously described Eubacterium species. The G + C content of the DNA is 45-46 mol% for Mogibacterium pumilum and 46 mol% for Mogibacterium vescum. The levels of DNA-DNA relatedness of these new species to other Eubacterium species, including Eubacterium limosum, Eubacterium brachy, Eubacterium lentum, Eubacterium nodatum, Eubacterium saphenum, and the more recently proposed Eubacterium minutum and Eubacterium exiguum (reclassified as Slackia exigua), are less than 2%. The DNA-DNA hybridization value between M. pumilum and M. vescum was 30%. Eubacterium timidum exhibited DNA homologies with Mogibacterium species which were low (17 and 18%) but clearly higher than with all the other Eubacterium species. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the closest phylogenetic neighbour of Mogibacterium species was E. timidum, and that these three species represent a novel lineage distinct from the previously described genera of Gram-positive, rod-shaped bacteria. On the basis of phenotypic characteristics and 16S rRNA gene sequence comparisons, it is also proposed that E. timidum is transferred to the genus Mogibacterium gen. nov. as Mogibacterium timidum gen. nov., comb. nov. (type strain ATCC 33093T).

Nakazawa F ，Sato M ，Poco SE ，Hashimura T ，Ikeda T ，Kalfas S ，Sundqvist G ，Hoshino E ... -  《international journal of systematic and evolutionary microbiology》

Novel chemolithotrophic, thermophilic, anaerobic bacteria Thermolithobacter ferrireducens gen. nov., sp. nov. and Thermolithobacter carboxydivorans sp. nov.

Three thermophilic strains of chemolithoautotrophic Fe(III)-reducers were isolated from mixed sediment and water samples (JW/KA-1 and JW/KA-2(T): Calcite Spring, Yellowstone N.P., WY, USA; JW/JH-Fiji-2: Savusavu, Vanu Levu, Fiji). All were Gram stain positive rods (approximately 0.5 x 1.8 microm). Cells occurred singly or in V-shaped pairs, and they formed long chains in complex media. All utilized H(2) to reduce amorphous iron (III) oxide/hydroxide to magnetite at temperatures from 50 to 75 degrees C (opt. approximately 73 degrees C). Growth occurred within the pH(60C) range of 6.5-8.5 (opt. pH(60C) 7.1-7.3). Magnetite production by resting cells occurred at pH(60C) 5.5-10.3 (opt. 7.3). The iron (III) reduction rate was 1.3 mumol Fe(II) produced x h(-1) x ml(-1) in a culture with 3 x 10(7) cells, one of the highest rates reported. In the presence or absence of H(2), JW/KA-2(T) did not utilize CO. The G + C content of the genomic DNA of the type strain is 52.7 +/- 0.3 mol%. Strains JW/KA-1 and JW/KA-2(T) each contain two different 16S rRNA gene sequences. The 16S rRNA gene sequences from JW/KA-1, JW/KA-2(T), or JW/JH-Fiji-2 possessed >99% similarity to each other but also 99% similarity to the 16S rRNA gene sequence from the anaerobic, thermophilic, hydrogenogenic CO-oxidizing bacterium 'Carboxydothermus restrictus' R1. DNA-DNA hybridization between strain JW/KA-2(T) and strain R1(T) yielded 35% similarity. Physiological characteristics and the 16S rRNA gene sequence analysis indicated that the strains represent two novel species and are placed into the novel genus Thermolithobacter within the phylum 'Firmicutes'. In addition, the levels of 16S rRNA gene sequence similarity between the lineage containing the Thermolithobacter and well-established members of the three existing classes of the 'Firmicutes' is less than 85%. Therefore, Thermolithobacter is proposed to constitute the first genus within a novel class of the 'Firmicutes', Thermolithobacteria. The Fe(III)-reducing Thermolithobacter ferrireducens gen. nov., sp. nov. is designated as the type species with strain JW/KA-2(T) (ATCC 700985(T), DSM 13639(T)) as its type strain. Strain R1(T) is the type strain for the hydrogenogenic, CO-oxidizing Thermolithobacter carboxydivorans sp. nov. (DSM 7242(T), VKM 2359(T)).

Sokolova T ，Hanel J ，Onyenwoke RU ，Reysenbach AL ，Banta A ，Geyer R ，González JM ，Whitman WB ，Wiegel J ... -  《EXTREMOPHILES》

Cryptobacterium curtum gen. nov., sp. nov., a new genus of gram-positive anaerobic rod isolated from human oral cavities.

Novel Eubacterium-like isolates, strains 12-3T and KV43-B, which were isolated from the periodontal pocket of an adult patient with periodontal disease and necrotic dental pulp, respectively, were studied taxonomically and phylogenetically. The morphological and differential biochemical characteristics of these organisms are also described in this paper. These organisms were Gram-positive, anaerobic, non-spore-forming, rod-shaped bacteria that were inert in most of the conventional biochemical tests and closely resembled members of asaccharolytic oral Eubacterium species. On the other hand, protein profiles of whole cells in SDS-PAGE and Western immunoblotting reaction analysis distinguished these isolates from strains of the previously described genus Eubacterium. The G+C content of the DNAs from the novel isolates was 50 and 51 mol%, respectively. The levels of DNA-DNA relatedness to other asaccharolytic oral Eubacterium species, including Eubacterium brachy, Eubacterium lentum, Eubacterium nodatum, Eubacterium timidum, Eubacterium saphenum, Eubacterium minutum and Eubacterium exiguum, was less than 11%. These organisms also exhibited a very low level of reassociation with the DNA of Eubacterium limosum, the type species of the genus Eubacterium. The results of 16S rDNA sequence comparisons revealed that these organisms represent a novel lineage distinct from all previously described genera of Gram-positive, rod-shaped bacteria. On the basis of our results, it is suggested that strains 12-3T and KV43-B should be classified in a new genus and species, for which the name Cryptobacterium curtum gen. nov., sp. nov. is proposed. The type strain of Cryptobacterium curtum is 12-3T (= ATCC 700683T).

Nakazawa F ，Poco SE ，Ikeda T ，Sato M ，Kalfas S ，Sundqvist G ，Hoshino E ... -  《-》