No abstract

A moderately thermophilic, sporeforming bacterium able to reduce amorphous Fe(III)-hydroxide was isolated from ferric deposits of a terrestrial hydrothermal spring, Kunashir Island (Kurils), and designated as strain Z-0001. Cells of strain Z-0001 were straight, Gram-positive rods, slowly motile. Strain Z-0001 was found to be an obligate anaerobe. It grew in the temperature range from 45 to 70 degrees C with an optimum at 57-60 degrees C, in a pH range from 5.9 to 8.0 with an optimum at 7.0-7.2, and in NaCl concentration range 0-3.5% with an optimum at 0%. Molecular hydrogen, acetate, peptone, yeast and beef extracts, glycogen, glycolate, pyruvate, betaine, choline, N-acetyl-D-glucosamine and casamino acids were used as energy substrates for growth in presence of Fe(III) as an electron acceptor. Sugars did not support growth. Magnetite, Mn(IV) and anthraquinone-2,6-disulfonate served as the alternative electron acceptors, supporting the growth of isolate Z-0001 with acetate as electron donor. Formation of magnetite was observed when amorphous Fe(III) hydroxide was used as electron acceptor. Yeast extract, if added, stimulated growth, but was not required. Isolate Z-0001 was able to grow chemolithoautotrophicaly with molecular hydrogen as the only energy substrate, Fe(III) as electron acceptor and CO(2) as the carbon source. Isolate Z-0001 was able to grow with 100% CO as the sole energy source, producing H(2) and CO(2), requiring the presence of 0.2 g l(-1) of acetate as the carbon source. The G+C content of strain Z-0001(T )DNA G+C was 47.8 mol%. Based on 16S rRNA sequence analyses strain Z-0001 fell into the cluster of family Peptococcaceae, within the low G+C content Gram-Positive bacteria, clustering with Thermincola carboxydophila (98% similarity). DNA-DNA hybridization with T. carboxydophila was 27%. On the basis of physiological and phylogenetic data it is proposed that strain Z-0001(T) (=DSMZ 14005, VKM B-2307) should be placed in the genus Thermincola as a new species Thermincola ferriacetica sp. nov.

No abstract

The first alkaliphilic obligately anaerobic hydrogenotrophic homoacetogenic bacterium, strain Z-7100T, was isolated from sediments of the soda-depositing soda lake Tanatar III (Altay, Russia). Cells were thin, flexible rods, motile, Gram-negative and spore-forming. The organism was an obligate alkaliphile, growing at pH 8.5 to 10.5, with optimum growth at pH 8.8–9.3, and it grew in soda brines containing 1.9–4.7 M total Na+ (optimum at 2.8–3.3 M). It exhibited an obligate dependence upon sodium carbonate but not upon chloride ions with an NaCl range for growth of 0–14 % (w/v) and an optimum at 7.0–8.5 % (w/v). The isolate was mesophilic and grew at temperatures from 25 to 45 °C, with an optimum at 40 °C. An H2+CO2 mixture, ethanol, pyruvate and lactate were utilized with the formation of acetate as the sole metabolic product. Carbohydrates and amino acids did not support growth. The isolate had a respiratory type of metabolism, reducing NO 3 – , SeO4 2− or anthraquinone-2,6-disulfonate (as electron acceptors with ethanol as an electron donor). It was able to grow chemolithotrophically on H2+CO2 in medium supplemented with a vitamin solution only. The major cellular fatty acids were the saturated fatty acids anteiso-C15, C14 : 0 and C16 : 0 and the aldehydes C16, C14 and anteiso-C15. The DNA G+C content of the isolate was 32.0 mol%. 16S rRNA gene sequence analysis showed that strain Z-7100T is a member of the order Halanaerobiales and represents a new branch within the family Halobacteroidaceae , clustering with the type strain of Selenihalanaerobacter shriftii (92.9 % gene sequence similarity). On the basis of its physiological characteristics and phylogenetic position, the isolate is considered to represent a novel species in a new genus within the family Halobacteroidaceae . The name Fuchsiella alkaliacetigena gen. nov., sp. nov. is proposed. The type strain of the type species is Z-7100T ( = DSM 24880T = VKM B-2667T).

No abstract

No abstract

No abstract

Thermovenabulum ferriorganovorum gen. nov., sp. nov., a novel thermophilic, anaerobic, endospore-forming bacterium Institute of Microbiology, Russian Academy of Sciences, Prospect 60-letiya Oktyabrya 7/2, A thermophilic, anaerobic, spore-forming bacterium (strain Z-9801 T) was isolated from a terrestrial hydrothermal source in the Uzon caldera on the Kamchatka peninsula. Cells of strain Z-9801 T were straight, sometimes branched rods, 05-06 µm in diameter and 15-70 µm in length, with peritrichous flagella. The temperature range for growth was 45-76 mC, with an optimum at 63-65 mC. The pH range for growth was 48-82, with an optimum at 67-69. The substrates utilized by strain Z-9801 T included peptone, yeast extract, beef extract, Casamino acids, starch, pyruvate, melibiose, sucrose, fructose, maltose, xylose and ribose. The fermentation products from melibiose were ethanol, acetate, H 2 and CO 2. Strain Z-9801 T used H 2 in the presence of Fe(III) and an organic electron donor. Strain Z-9801 T reduced Fe(III), Mn(IV), nitrate, fumarate, sulfite, thiosulfate, elemental sulfur and 9,10-anthraquinone 2,6-disulfonate. The GMC content of strain Z-9801 T DNA was 36 mol %. 16S rDNA sequence analysis revealed that the isolated organism forms a separate branch within the Bacillus/Clostridium group. On the basis of physiological properties and phylogenetic analysis, it is proposed that strain Z-9801 T (l DSM 14006 T l UNIQEM 210 T) should be assigned to a novel species of a new genus, Thermovenabulum ferriorganovorum gen. nov., sp. nov.