Tepidibacillus fermentans gen. nov., sp. nov.: a moderately thermophilic anaerobic and microaerophilic bacterium from an underground gas storage

A novel moderately thermophilic bacterium, strain STGH^T, was isolated from Severo-Stavropolskoye underground gas storage (Russia). Cells of strain STGH^T were spore-forming motile straight rods 0.3 μm in diameter and 2.0–4.0 μm in length having a Gram-positive cell wall structure. The temperature range for growth was 36–65 °C, with an optimum at 50–52 °C. The pH range for growth was 5.5–8.0, with an optimum at pH 7.0–7.5. Growth of strain STGH^T was observed at NaCl concentrations ranging from 0 to 4.0 % (w/v) with an optimum at 1.0 % (w/v). Strain STGH^T grew anaerobically by reduction of nitrate, thiosulfate, S⁰ and AQDS using a number of complex proteinaceous compounds, organic acids and carbohydrates as electron donors. Nitrate was reduced to nitrite; thiosulfate and sulfur were reduced to sulfide. It also was able to ferment pyruvate, glucose, fructose, and maltose. The strain STGH^T did not grow under aerobic conditions during incubation with atmospheric concentration of oxygen but was able to microaerobic growth (up to 10 % of oxygen in gas phase). The G+C content of DNA of strain STGH^T was 34.8 mol%. 16S rRNA gene sequence analysis revealed that the isolated organism belongs to the class Bacilli. We propose to assign strain STGH^T to a new species of a novel genus Tepidibacillus fermentans gen. nov., sp.nov. The type strain is STGH^T (=DSM 23802^T, =VKM B-2671^T).     

Reduction of chromate, selenite, tellurite, and iron(III) by the moderately thermophilic bacterium Bacillus thermoamylovorans SKC1

A moderately thermophilic, facultatively anaerobic bacterium capable of reducing Cr(VI) (strain SKC1) was isolated from municipal sewage. Based on the analysis of the 16S rRNA gene nucleotide sequence and DNA-DNA hybridization data, strain SKC1 was identified as a representative of the species Bacillus thermoamylovorans. B. thermoamylovorans SKC1 is capable of reducing chromate with L-arabinose as an electron donor with an optimum at 50 degrees C and neutral pH. The culture is able to reduce Cr(VI) at its initial concentration in the medium of up to 150 mg/l. In addition to chromate, strain SKC1 is capable of reducing selenite and tellurite, as well as soluble forms of Fe(III). It was shown that Cr(VI), Te(IV), and Se(IV) exert a bacteriostatic effect on strain SKC1, and the reduction of these anions performs the detoxification function. This is the first communication on the reduction of chromate, selenite, tellurite, and soluble Fe(III) species by a culture of thermophilic bacilli.     

Detection of a cultivated hyperthermophilic archaeon of the genus Sulfophobococcus in a methane tank operated in a thermophilic regime

A stable association of hyperthermophilic microorganisms (82 degrees C), which contained mostly cocci and a minor amount of non-spore-forming rods, was obtained from the fermented sludge of a methane tank used to process municipal wastewaters under thermophilic conditions (50 degrees C). PCR amplification of 16S rRNA genes using total DNA isolated from this association and archaea-specific primers, followed by sequencing of the product obtained, showed that the archaeal component was represented by a single nucleotide sequence, which was 99.9% homologous to 16S rRNA gene of Sulfophobococcus zilligii. Thus, a hyperthermophilic archaeon was for the first time detected in a system of anaerobic biological treatment of wastewater. In addition, this is the first report on the detection of a cultivated member of Crenarchaeota in anthropogenic habitats with neutral pH.     

<Emphasis Type="Italic">Thermosulfurimonas marina</Emphasis> sp. nov., an Autotrophic Sulfur-Disproportionating and Nitrate-Reducing Bacterium Isolated from a Shallow-Sea Hydrothermal Vent

A thermophilic, anaerobic, chemolithoautotrophic bacterium (strain SU872^T) was isolated from a shallow-sea hydrothermal vent at Kunashir Island. The cells were motile, gram-negative, oval or rodshaped 0.5?0.6 μm thick and 1.5?2.0 μm long, occurring singly or in pairs. Strain SU872^T grew at 50 to 79°C (optimum at 74°C), pH from 5.0 to 8.0 (optimum at 6.7?7.0), and NaCl concentration of 1.5–4.5%. Strain SU872^T was able to grow by disproportionation of elemental sulfur, thiosulfate, or sulfite, with CO₂/HCO₃^? as the sole carbon source. Growth was enhanced in the presence of ferrihydrite (poorly crystalline Fe(III) oxide) as as a sulfide-scavenging agent. Sulfate was not used as an electron acceptor. Growth also occurred with elemental sulfur, thiosulfate, or sulfite (but not sulfide) as electron donors and nitrate as an electron acceptor, with production of sulfate and ammonium. Analysis of the 16S rRNA gene sequence revealed 97.8% similarity between strain SU872^T and the type strain Thermosulfurimonas dismutans S95^T (phylum Thermodesulfobacteria). According to the results of DNA–DNA hybridization, the similarity of genomic DNA of the strains SU872^T and T. dismutans S95^T was 48%. Based on its phenotypic characteristics and the results of phylogenetic analysis, it is proposed to assign the isolate to a new species of the genus Thermosulfurimonas,—Thermosulfurimonas marina sp. nov., with the type strain SU872^T (=DSM 104922^T, =VKM B-3177^T, =UNIQEM SU872^T).     

Stages in the improvement of drug therapy at a polyclinic]

Within 1968-1997 the authors studied the steps of introduction of the achievements of the medical science, technology and pharmacology to therapy of exacerbations and complications of peptic ulcer (PU). The scientific and practical value of endoscopic, histological, biochemical and bacteriological examinations in the improvement of the methods of pharmacotherapy of exacerbations and complications of PU was shown. Three phases of the PU development were indicated by the clinical signs and results of esophagogastroduodenoscopy, target biopsy and histological examinations. These data and available scientific achievements were assumed as a basis for the design of optimal drug combinations and their introduction to the medical practice. The use of such combinations made it possible to prevent relapses and life-threatening complications of the disease in the overwhelming majority of the patients. The best results of the pharmacotherapy were recorded in the years (1988-1997) when the drug combinations began to be used. The combinations provided eradication of Helicobacter pylori in the gastroduodenal mucosa and it was proved that in all the patients with PU and the relapsing lesions in the duodenum and in the overwhelming majority of the patients with gastric ulcer the disease developed at the background of chronic active gastroduodenitis associated with H.pylori. The success of the pharmacotherapy in the patients with PU was due to the use of the rational combinations of antibacterial and antisecretory agents.     

PCR-based identification of hyperthermophilic archaea of the family Thermococcaceae

A method for rapid detection and identification of hyperthermophilic archaea of the family Thermococcaceae based on PCR amplification of 16S rRNA gene fragments with primers TcPc 173F (5'-TCCCCCATAGGYCTGRGGTACTGGAAGGTC-3') and TcPc 589R (5'-GCCGTGRGATTTCGCCAGGGACTTACGGGC-3') was developed and used for identification of new isolates.     

Tepidibaculum saccharolyticum gen. nov., sp. nov. a moderately thermophilic,anaerobic, spore-forming bacterium isolated from a terrestrial hot spring

Extremophiles - A novel moderately thermophilic, anaerobic bacterium, strain STR9T was isolated from terrestrial hot spring at Uzon Caldera, Kamchatka peninsula, Russia. Cells of strain STR9T were...     

Microbial diversity and autotrophic activity in Kamchatka hot springs

Microbial communities of Kamchatka Peninsula terrestrial hot springs were studied using molecular, radioisotopic and cultural approaches. Analysis of 16S rRNA gene fragments performed by means of high-throughput sequencing revealed that aerobic autotrophic sulfur-oxidizing bacteria of the genus Sulfurihydrogenibium (phylum Aquificae) dominated in a majority of streamers. Another widely distributed and abundant group was that of anaerobic bacteria of the genus Caldimicrobium (phylum Thermodesulfobacteria). Archaea of the genus Vulcanisaeta were abundant in a high-temperature, slightly acidic hot spring, where they were accompanied by numerous Nanoarchaeota, while the domination of uncultured Thermoplasmataceae A10 was characteristic for moderately thermophilic acidic habitats. The highest rates of inorganic carbon assimilation determined by the in situ incubation of samples in the presence of ¹⁴C-labeled bicarbonate were found in oxygen-dependent streamers; in two sediment samples taken from the hottest springs this process, though much weaker, was found to be not dependent on oxygen. The isolation of anaerobic lithoautotrophic prokaryotes from Kamchatka hot springs revealed a wide distribution of the ability for sulfur disproportionation, a new lithoautotrophic process capable to fuel autonomous anaerobic ecosystems.

     

Complete genome sequence of strain 1860, a crenarchaeon of the genus Pyrobaculum able to grow with various electron acceptors

Strain 1860, a novel member of the genus Pyrobaculum, is a hyperthermophilic organotrophic crenarchaeon growing anaerobically with various electron acceptors. The complete genome sequence reveals genes for several membrane-bound oxidoreductases, the Embden-Meyerhof and Entner-Doudoroff pathways for glucose metabolism, the tricarboxylic acid cycle, the glyoxylate cycle, and the dicarboxylate/4-hydroxybutyrate cycle.     

Reduction of chromate,selenite, tellurite,and iron (III) by the moderately thermophilic bacterium <Emphasis Type="Italic">Bacillus thermoamylovorans</Emphasis> SKC1

A moderately thermophilic, facultatively anaerobic bacterium capable of reducing Cr(VI) (strain SKC1) was isolated from municipal sewage. Based on the analysis of the 16S rRNA gene nucleotide sequence and DNA-DNA hybridization data, strain SKC1 was identified as a representative of the species Bacillus thermoamylovorans. B. thermoamylovorans SKC1 is capable of reducing chromate with L-arabinose as an electron donor with an optimum at 50°C and neutral pH. The culture is able to reduce Cr(VI) at its initial concentration in the medium of up to 150 mg/l. In addition to chromate, strain SKC1 is capable of reducing selenite and tellurite, as well as soluble forms of Fe(III). It was shown that Cr(VI), Te(IV), and Se(IV) exert a bacteriostatic effect on strain SKC1, and the reduction of these anions performs the detoxification function. This is the first communication on the reduction of chromate, selenite, tellurite, and soluble Fe(III) species by a culture of thermophilic bacilli.