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2.
Int J Syst Evol Microbiol ; 59(Pt 12): 3116-22, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19643887

RESUMO

An anaerobic acidophilic, hyperthermophilic archaeon, designated strain 345-15(T), was isolated from an acidic hot spring of Kamchatka (Russia). Cells of strain 345-15(T) were regular or irregular cocci, 1-2 mum in diameter, with flagella. Strain 345-15(T) grew optimally at 80-85 degrees C and pH 3.5-4.0 and fermented a wide range of carbohydrates, including polysaccharides. Acetate, ethanol and lactate were the fermentation products. Growth was stimulated by elemental sulfur and thiosulfate, which were reduced to hydrogen sulfide. The G+C content of the DNA was 54.5 mol%. The 16S rRNA gene sequence analysis indicated that strain 345-15(T) belonged to the genus Acidilobus. The level of DNA-DNA hybridization between strain 345-15(T) and Acidilobus aceticus 1904(T) was 61 %. Thus, strain 345-15(T) was considered as representing a novel species of the genus Acidilobus, with the name Acidilobus saccharovorans sp. nov. (type strain, 345-15(T)=DSM 16705(T)=VKM B-2471(T)), which shared the main morphological and physiological properties of the genus but differed by the presence of flagella and the spectrum of substrates utilized. Phylogenetic analysis showed that the genus Acidilobus, with its species Acidilobus aceticus, Acidilobus saccharovorans sp. nov. and 'Acidilobus sulfurireducens', and the genus Caldisphaera, represented by Caldisphaera lagunensis and 'Caldisphaera draconis', formed a separate cluster that adjoins the cluster formed by the species of the order Desulfurococcales. Members of the Acidilobus-Caldisphaera cluster are thermophilic, organotrophic anaerobic cocci that can be distinguished from all species of the order Desulfurococcales on the basis of acidophily. Based on these considerations, we propose a new family, Acidilobaceae fam. nov., to accommodate the subcluster of hyperthermophiles represented by the genus Acidilobus, a new family, Caldisphaeraceae fam. nov., for the subcluster of extreme thermophiles represented by the genus Caldisphaera, and a new order, Acidilobales ord. nov., to accommodate the two new families.


Assuntos
Crenarchaeota/classificação , Crenarchaeota/isolamento & purificação , Fontes Termais/microbiologia , Anaerobiose , Crenarchaeota/genética , DNA Arqueal/genética , DNA Ribossômico/genética , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética
3.
Mikrobiologiia ; 78(1): 98-105, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19334602

RESUMO

A novel halotolerant psychrotrophic gram-negative bacterium, strain 2pS, was isolated from lenses of water brine in Arctic permafrost (cryopeg). The optimal growth of the new strain was observed at 16-18 degrees C; the maximal and minimal growth temperatures were 37 degrees C and -2 degrees C, respectively. The pH growth range was 5.8 to 8.5 (optimum 6.5-7.5) and the range of medium salinity was 0 to 100 g/l (optimum 3-8 g/l NaCl). The strain 2pS did not produce acid from carbohydrates and utilized acetate, yeast extract, pyruvate, glutarate, fumarate, caproate, heptanoate, butyrate, malate, DL-lactate, citrate, L-proline, L-tyrosine, butanol, and dulcitol as the sole carbon and energy sources. The major fatty acids of the cell wall at optimal growth temperature were C18:1(omega 7) and C18:1(omega 9). The G + C DNA content was 46.0 mol.%. Phylogenetic analysis of the 16S rRNA gene sequences showed that the studied strain was the closest (97% similarity) to Psychrobacter nivimaris DSM 16093T, a halotolerant psychrotrophic bacterium isolated from the Arctic sea's ice. Genotypic and phenotypic differences of the new bacterium from closely related species lead to the conclusion that strain 2pS belongs to a novel species of the genus Psychrobacter: Psychrobacter muriicola sp. nov.


Assuntos
Moraxellaceae/classificação , Salinidade , Água do Mar/microbiologia , Microbiologia da Água , Regiões Árticas , Metabolismo dos Carboidratos , Parede Celular/metabolismo , Meios de Cultura , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Dados de Sequência Molecular , Moraxellaceae/citologia , Moraxellaceae/genética , Moraxellaceae/metabolismo , Fenótipo , Filogenia , Homologia de Sequência do Ácido Nucleico , Especificidade por Substrato , Temperatura
4.
Mikrobiologiia ; 77(2): 178-87, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18522318

RESUMO

Five cultures of moderately thermophilic spore-forming acidophilic chemolithotrophic bacteria were isolated from the zones of spontaneous heating of pyrrhotine-containing pyrite-arsenopyrite gold-arsenic sulfide ores in an operating open pit (strains B1, B2, B3, OFO, and SSO). Analysis of the chromosomal DNA structure revealed differences between these cultures at the strain level (apart from B3 and SSO, which had identical restriction profiles). All the strains had a similar G + C DNA molar content (47.4-48.3%). The level of DNA reassociation was 85 to 95%. The similarity between the DNA of the type strain Sulfobacillus sibiricus N1 isolated from arsenopyrite ore concentrate and that of these strains (83-93%) indicates that they belong to the same species. The strains had similar values of pH and temperature optimal for growth on ferrous iron (1.6-2.0 and 45-55 degrees C, respectively). They were mixotrophs; Fe(II), S0, and sulfide minerals along with organic compounds were used as energy sources and electron donors. However, the kinetic parameters of growth and substrate oxidation varied from strain to strain. Genetic variety of the strains from diverse ecosystems and environments is possibly the result of the different rates of microevolution processes.


Assuntos
Bacillus/fisiologia , Bacillus/classificação , Bacillus/isolamento & purificação , Composição de Bases , Biodiversidade , DNA Bacteriano/genética , Compostos Ferrosos/metabolismo , Sedimentos Geológicos/microbiologia , Concentração de Íons de Hidrogênio , Compostos Orgânicos/metabolismo , Oxirredução , Sulfatos/metabolismo , Enxofre/metabolismo , Temperatura
5.
Mikrobiologiia ; 76(4): 533-44, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17974211

RESUMO

The anoxygenic phototrophic bacterial community of the brackish meromictic Lake Shira (Khakassia) was investigated in August 2001, July 2002, and February-March 2003. In all the periods of investigation, the prevailing microorganisms were purple sulfur bacteria similar to Lamprocystis purpurea in morphology and pigment composition. Their highest number (3 x 10(5) cells/ml) was recorded in July 2002 at the depth of 15 m. According to 16S rRNA gene analysis, the strain of purple sulfur bacteria isolated in 2001 and designated ShAm01 exhibited 98.6% similarity to the type strain of Thiocapsa roseopersicina and 94.4-97.1% similarity to the type strains of Tca. pendens, Tca. litoralis, and Tea. rosea. The minor microorganisms of the anoxygenic phototrophic bacterial community within the period of investigation were nonsulfur purple bacteria phylogenetically close to Rhodovulum strictum (98.3% similarity, strain ShRb01), Ahrensia kielensis (of 93.9% similarity, strain ShRb02), Rhodomicrobium vannieli (of 99.7% similarity, strain ShRmc01), and green sulfur bacteria, phylogenetically close to Chlorobium limicola (of 98.7% similarity, strain ShCl03).


Assuntos
Chlorobi/isolamento & purificação , Chromatiaceae/isolamento & purificação , Água Doce/microbiologia , Rhodospirillaceae/isolamento & purificação , Chlorobi/classificação , Chromatiaceae/classificação , Ecossistema , Processos Fototróficos , Filogenia , Rhodospirillaceae/classificação
6.
Mikrobiologiia ; 76(3): 416-28, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17633417

RESUMO

Seasonal studies of the anoxygenic phototrophic bacterial community of the water column of the saline eutrophic meromictic Lake Shunet (Khakassia) were performed in 2002 (June) and 2003 (February-March and August). From the redox zone down, the lake water was of dark green color. Green sulfur bacteria predominated in every season. The maximum number of green sulfur bacteria was 10(7) cells/ml in summer and 10(6) cells/ml in winter. A multi-syringe stratification sampler was applied for the study of the fine vertical distribution of phototrophs in August 2003; the sampling was performed every five centimeters. A five-centimeter-thick pink-colored water layer inhabited by purple sulfur bacteria was shown to be located above the layer of green bacteria. The species composition and ratio of purple bacterial species depended on the sampling depth and on the season. In summer, the number of purple sulfur bacteria in the layer of pink water was 1.6 x 10(8) cells/ml. Their number in winter was 3 x 10(5) cells/ml. In the upper oxygen-containing layer of the chemocline the cells of purple nonsulfur bacteria were detected in summer. The maximum number of nonsulfur purple bacteria, 5 x 10(2) cells/ml, was recorded in August 2003. According to the results of the phylogenetic analysis of pure cultures of the isolated phototrophic bacteria, which were based on 16S rDNA sequencing, green sulfur bacteria were close to Prosthecochloris vibrioformis, purple sulfur bacteria, to Thiocapsa and Halochromatium species, and purple nonsulfur bacteria, to Rhodovulum euryhalinum and Pinkicyclus mahoneyensis.


Assuntos
Monitoramento Ambiental , Água Doce/microbiologia , Rhodobacteraceae/isolamento & purificação , Estações do Ano , Microbiologia da Água , Anaerobiose , Água Doce/análise , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Rhodobacteraceae/genética , Rhodobacteraceae/ultraestrutura , Sibéria
7.
Mikrobiologiia ; 76(6): 834-43, 2007.
Artigo em Russo | MEDLINE | ID: mdl-18297876

RESUMO

In the course of the search for N2O-utilizing microorganisms, two novel strains of haloalkaliphilic denitrifying bacteria, Z-7009 and AIR-2, were isolated from soda lakes of Mongolia and Kenya. These microorganisms are true alkaliphiles and grow in the pH ranges of 8.0-10.5 and 7.5-10.6, respectively. They are facultative anaerobes with an oxidative type of metabolism, able to utilize a wide range of organic substrates and reduce nitrate, nitrous oxide, and, to a lesser extent, nitrite to gaseous nitrogen. They can oxidize sulfide in the presence of acetate as the carbon source and nitrous oxide (strain Z-7009) or nitrate (strain AIR-2) as the electron acceptor. The strains require Na+ ions. They grow at medium mineralization levels of 0.16-2.2 M Na+ (Z-7009) and 0.04-2.2 M Na+ (AIR-2). The G+C contents of the DNA of strains Z-7009 and AIR-2 are 67.9 and 65.5 mol %, respectively. According to the results of 16S rRNA gene sequencing and DNA-DNA hybridization, as well as on the basis of physiological properties, the strains were classified as new species of the genus Halomonas: Halomonas mongoliensis, with the type strain Z-7009T (=DSM 17332, =VKM B2353), and Halomonas kenyensis, with the type strain AIR-2T (=DSM 17331, =VKM B2354).


Assuntos
Halomonas/isolamento & purificação , Halomonas/fisiologia , Óxido Nitroso/metabolismo , Composição de Bases , Meios de Cultura , DNA Bacteriano/genética , Gases/metabolismo , Halomonas/classificação , Concentração de Íons de Hidrogênio , Quênia , Mongólia , Nitratos/metabolismo , Nitrogênio/metabolismo , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Temperatura , Microbiologia da Água
8.
Mikrobiol Z ; 68(4): 10-20, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17100323

RESUMO

Two orange-pigmented Gram-positive, aerobic bacteria were isolated from enrichment culture during degradation of brown alga Fucus evanescens thalluses. In this work, atomic force microscopy (AFM) has been used to study the cell morphology. The non-contact mode imaging revealed unusual irregular coccoid shape of cells, possessing a single flagellum. Bacteria produced carotenoid pigments, were chemo-organotrophic, alkaliphilic and halo-tolerant growing well on nutrient media containing up to 15% NaCl. Growth temperature ranged from 5 to 45 degrees C. The DNA base compositions were 48 mol% G + C and the level of DNA similarity of two strains was conspecific (98%). A comparative phylogenetic analysis of 16S rRNA gene sequences revealed that the strain KMM 3738 tightly clustered with recently described Planococcus maritimus (99.9% 16S rRNA gene sequence similarity). DNA-DNA hybridisation experiments revealed that DNA from the KMM 3738 showed 12-15% and 16-35% of genetic relatedness with the DNA of type strains of the genera Planomicrobium and Planococcus, respectively, and 87% with DNA from Planococcus maritimus, indicating that new isolates belong to the later species.


Assuntos
Fucus/microbiologia , Bactérias Gram-Positivas/isolamento & purificação , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/ultraestrutura , Microscopia Eletrônica de Transmissão , Filogenia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
9.
Int J Syst Evol Microbiol ; 56(Pt 10): 2349-2351, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17012560

RESUMO

Similarities in phylogeny and metabolic properties between the type species of two monospecific genera of thermophilic anaerobic bacteria, Carboxydothermus hydrogenoformans and Thermoterrabacterium ferrireducens, and analysis of their recently available 16S rRNA gene sequences warranted clarification of their taxonomic positions. We have determined that the value of DNA-DNA hybridization between the type strains is 53 %. Additional physiological studies revealed that C. hydrogenoformans Z-2901(T) is capable of Fe(III) reduction with H(2) as an electron donor and ferrihydrite as an electron acceptor. T. ferrireducens JW/AS-Y7(T) is able to grow and utilize CO with ferrihydrite as an electron acceptor without hydrogen or acetate production. We therefore reclassify Thermoterrabacterium ferrireducens as Carboxydothermus ferrireducens comb. nov. (type strain JW/AS-Y7(T)=DSM 11255(T)=VKM B-2392(T)). The description of the genus Carboxydothermus is emended to include such important physiological properties as growth on organic compounds and capacity for Fe(III) reduction.


Assuntos
Peptococcaceae/classificação , Monóxido de Carbono/metabolismo , DNA Bacteriano/análise , Compostos Férricos/metabolismo , Genes de RNAr , Hibridização de Ácido Nucleico , Oxirredução , Peptococcaceae/genética , Peptococcaceae/metabolismo , Peptococcaceae/fisiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Mikrobiologiia ; 75(3): 377-82, 2006.
Artigo em Russo | MEDLINE | ID: mdl-16871805

RESUMO

Strain Z-0024, a psychrotolerant aerobic heterotrophic representative of the prosthecate bacteria of the genus Caulobacter, was isolated from a methanotrophic enrichment obtained from Russian polar tundra soil. The cells of the new isolate are vibrios (0.5-0.6 x 1.3-1.8 microm) with a polar stalk. The organism grows in a temperature range from 5 to 36 degrees C, with an optimum at 20 degrees C. The pH range for growth is from 4.5 to 7.0 with an optimum at pH 6.0. Strain Z-0024 utilizes a wide range of organic compounds: sugars, amino acids, volatile fatty acids, and primary alcohols. It tolerates a NaCl concentration in the medium of up to 15 g/l. The G + C content of DNA is 66.6 mol %. The 16S rRNA gene sequence analysis revealed that strain Z-0024 belongs to the cluster of Caulobacter species, showing a 98.8-99.2% sequence similarity to them. DNA-DNA hybridization revealed a low level of homology (24%) between strain Z-0024 and C. vibrioides ATCC 15252. The new isolate is described as Caulobacter sp. Z-0024.


Assuntos
Caulobacter/isolamento & purificação , Microbiologia do Solo , Composição de Bases , Caulobacter/citologia , Caulobacter/fisiologia , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Compostos Orgânicos/metabolismo , Filogenia , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Federação Russa , Especificidade da Espécie , Temperatura
11.
Mikrobiologiia ; 75(2): 201-11, 2006.
Artigo em Russo | MEDLINE | ID: mdl-16758868

RESUMO

The new mesophilic, chemolithoautotrophic, moderately halophilic, sulfate-reducing bacterium strain 11-6 could grow at a NaCl concentration in the medium of 30-230 g/l, with an optimum at 80-100 g/l. Cells were vibrios motile at the early stages of growth. Lactate, pyruvate, malate, fumarate, succinate, propionate, butyrate, crotonate, ethanol, alanine, formate, and H2 + CO2 were used in sulfate reduction. Butyrate was degraded completely, without acetate accumulation. In butyrate-grown cells, a high activity of CO dehydrogenase was detected. Additional growth factors were not required. Autotrophic growth occurred, in the presence of sulfate, on H2 + CO2 or formate without other electron donors. Fermentation of pyruvate and fumarate was possible in the absence of sulfate. Apart from sulfate, sulfite, thiosulfate, and elemental sulfur were able to serve as electron acceptors. The optimal growth temperature was 37 degrees C; the optimum pH was 7.2. Desulfoviridin was not detected. Menaquinone MK-7 was present. The DNA G+C content was 55.2 mol %. Phylogenetically, the bacterium represented a separate branch within the cluster formed by representatives of the family Desulfohalobiaceae in the subclass Deltaproteobacteria. The bacterium was assigned to a new genus and species, Desulfovermiculus halophilus gen. nov., sp. nov. The type strain is 11-6T (= VKM B-2364), isolated from the highly mineralized formation water of an oil field.


Assuntos
Deltaproteobacteria/crescimento & desenvolvimento , Deltaproteobacteria/metabolismo , Petróleo/microbiologia , Bactérias Redutoras de Enxofre/crescimento & desenvolvimento , Bactérias Redutoras de Enxofre/metabolismo , Ácidos Carboxílicos/metabolismo , Deltaproteobacteria/ultraestrutura , Genótipo , Concentração de Íons de Hidrogênio , Oxirredução , Oxirredutases/análise , Filogenia , RNA Ribossômico 16S/genética , Sulfatos/metabolismo , Bactérias Redutoras de Enxofre/ultraestrutura , Temperatura
12.
Mikrobiologiia ; 75(2): 212-20, 2006.
Artigo em Russo | MEDLINE | ID: mdl-16758869

RESUMO

New microaerophilic sulfur-oxidizing spirilla were isolated from hydrogen sulfide sludge of wastewater treatment plants. Strains D-427 and D-430 have spiral cells that are highly motile due to bipolar flagellum bundles covered with mucous sheaths. Under a phase-contrast microscope, these bundles are visible as single polar flagella. Spheroplasts are formed in the stationary growth phase. Both strains are obligate organotrophs able to oxidize a number of reduced sulfur compounds. The oxidation of sulfide and polysulfide leads to the formation of intracellular globules of elemental sulfur; thiosulfate oxidation results in tetrathionate accumulation in the medium. The cells are unable to utilize reduced sulfur compounds in the energy metabolism; their oxidation is caused by a chemical interaction with H2O2 and O2, synthesized in the electron transport chain. Both strains are obligate microaerophiles with an optimal oxygen concentration in the gas phase of 2 and 0.8% for strains D-427 and D-430, respectively. The strains utilize a limited number of organic acids as growth substrates, mainly tricarboxylic-acid-cycle intermediates. The DNA G+C content is 38.0 mol % (T(m)) for strain D-427 and 38.9 mol % for strain D-430. Phylogenetic analysis, based on the comparison of 16S rRNA gene sequences, revealed that the new isolates of sulfur spirilla are the most closely related to Spirillum volutans, the type species of the genus (97.4% similarity). They were assigned to the genus Spirillum within the class Beta-proteobacteria as two new species, S. winogradskii sp. nov. (D-427T = DSM 12756T) and S. kriegii sp. nov. (B-430T = BKM B-2372T). The emended description of the genus Spirillum is provided.


Assuntos
Esgotos/microbiologia , Spirillum/metabolismo , Spirillum/ultraestrutura , Enxofre/metabolismo , Microbiologia da Água , Genótipo , Oxigênio/farmacologia , Filogenia , Spirillum/isolamento & purificação , Sulfetos/metabolismo
13.
Mikrobiologiia ; 75(1): 118-26, 2006.
Artigo em Russo | MEDLINE | ID: mdl-16579453

RESUMO

This paper reports on the study of acid tolerance of lactic acid bacteria as a property of cells, determining their ability to divide efficiently and retain viability under conditions of increased nutrient medium acidity during bacterial growth. The bacteria of the strain TV2, isolated from a self-soured curd, similar to the bacteria of the strain STE05 (Russian National Collection of Industrial Microorganisms), were assigned to the species Lactococcus lactis according to their G+C composition (36.7-36.5 mol %) and the high level of DNA-DNA hybridization (93%). However, these strains were essentially different in the number and size of the plasmids and the chromosomal DNA restriction fragments, as well as in the sensitivity to phages of lactic acid bacteria. It was found that bacteria of the strain TV2 were stable (i.e., they divided efficiently at a pH as low as 5.3) and tolerant to the lactic acid that they produced while growing (i.e., they retained viability at pH 4.4). Bacteria of the strain STE05 lacked acid tolerance (at pH below 6.5, growth was retarded, and pH 5.0 was the lowest value at which the cells remained viable). The acid tolerance and phage resistance of TV2 bacteria are likely to characterize their higher adaptive capacity in comparison with STE05 bacteria. Acid tolerance is inherited in a stable manner and retained by the segregants of TV2 strain obtained in the course of long-term storage of the bacteria. Specifically, the strains TV29, TV13, and TV 229, which displayed this property, had altered physiological and biochemical characteristics (accumulation of biomass and fermentation of lactose) in spite of their genetic identity to the original strain (pulsed-field gel electrophoresis of chromosomal DNA restriction fragments).


Assuntos
Adaptação Fisiológica/genética , Cromossomos Bacterianos/genética , Variação Genética/genética , Lactococcus lactis/genética , Composição de Bases/genética , Concentração de Íons de Hidrogênio , Lactococcus lactis/crescimento & desenvolvimento , Especificidade da Espécie
14.
Int J Syst Evol Microbiol ; 56(Pt 2): 369-372, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16449442

RESUMO

A moderately thermophilic, anaerobic bacterium (strain SB91T) was isolated from a freshwater hot spring at Barguzin Valley, Buryatiya, Russia. Cells of strain SB91T were straight to slightly curved rods, 0.5-0.6 microm in diameter and 3.0-7.0 mum in length. Formation of endospores was not observed. The temperature range for growth was 26-62 degrees C, with an optimum at 50 degrees C. The pH range for growth was 5.5-9.5, with an optimum at pH 7.5-8.0. The substrates utilized by strain SB91T in the presence of 9,10-anthraquinone 2,6-disulfonate included peptone, tryptone, Casamino acids, yeast extract, beef extract, casein hydrolysate, alanine plus glycine, alanine plus proline, L-valine and n-propanol. Carbohydrates were not utilized. Strain SB91T reduced amorphous Fe(III) oxide, Fe(III) citrate, Fe(III) EDTA or Fe(III) nitrilotriacetate with peptone, L-valine or n-propanol as an electron donor. Strain SB91T reduced 9,10-anthraquinone 2,6-disulfonate, thiosulfate, elemental sulfur, fumarate and selenite. Strain SB91T survived after exposure to gamma-radiation at a dose of 5.4 kGy. The G+C content of the DNA of strain SB91T was 33 mol%. Analysis of the 16S rRNA gene sequence revealed that the isolated organism belonged to cluster XII of the clostridia. On the basis of its physiological properties and the results of phylogenetic analyses, it is proposed that strain SB91T represents the sole species of a novel genus, Tepidimicrobium; the name Tepidimicrobium ferriphilum gen. nov., sp. nov. is proposed, with strain SB91T (=DSM 16624T=VKM B-2348T) as the type strain.


Assuntos
Bactérias Anaeróbias/classificação , Compostos Férricos/metabolismo , Bacilos Gram-Positivos Asporogênicos Irregulares/classificação , Fontes Termais/microbiologia , Temperatura Alta , Bactérias Anaeróbias/genética , Bactérias Anaeróbias/isolamento & purificação , Bactérias Anaeróbias/fisiologia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , DNA Ribossômico/análise , Genes de RNAr , Bacilos Gram-Positivos Asporogênicos Irregulares/genética , Bacilos Gram-Positivos Asporogênicos Irregulares/isolamento & purificação , Bacilos Gram-Positivos Asporogênicos Irregulares/fisiologia , Ferro/metabolismo , Dados de Sequência Molecular , Oxirredução , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA
15.
Mikrobiologiia ; 74(5): 654-62, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16315984

RESUMO

This study focused on the physiological, chemotaxonomic, and genotypic characteristics of two thermophilic spore-forming sulfate-reducing bacterial strains, 435T and 781, of which the former has previously been assigned to the subspecies Desulfotomaculum nigrificans subsp. salinus. Both strains reduced sulfate with the resulting production of H2S on media supplemented with H2 + CO2, formate, lactate, pyruvate, malate, fumarate, succinate, methanol, ethanol, propanol, butanol, butyrate, valerate, or palmitate. Lactate oxidation resulted in acetate accumulation; butyrate was oxidized completely, with acetate as an intermediate product. Growth on acetate was slow and weak. Sulfate, sulfite, thiosulfate, and elemental sulfur, but not nitrate, served as electron acceptors for growth with lactate. The bacteria performed dismutation of thiosulfate to sulfate and hydrogen sulfide. In the absence of sulfate, pyruvate but not lactate was fermented. Cytochromes of b and c types were present. The temperature and pH optima for both strains were 60-65 degrees C and pH 7.0. Bacteria grew at 0 to 4.5-6.0% NaCl in the medium, with the optimum being at 0.5-1.0%. Phylogenetic analysis based on a comparison of incomplete 16S rRNA sequences revealed that both strains belonged to the C cluster of the genus Desulfotomaculum, exhibiting 95.5-98.3% homology with the previously described species. The level of DNA-DNA hybridization of strains 435T and 781 with each other was 97%, while that with closely related species D. kuznetsovii 17T was 51-52%. Based on the phenotypic and genotypic properties of strains 435T and 781, it is suggested that they be assigned to a new species: Desulfotomaculum salinum sp. nov., comb. nov. (type strain 435T = VKM B 1492T).


Assuntos
Desulfotomaculum/classificação , Desulfotomaculum/fisiologia , Sulfatos/metabolismo , Meios de Cultura , Desulfotomaculum/química , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Compostos Orgânicos/metabolismo , Oxirredução , Filogenia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Homologia de Sequência , Especificidade da Espécie , Sulfitos/metabolismo
16.
Mikrobiologiia ; 74(5): 642-53, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16315983

RESUMO

The first anaerobic alkaliphilic cellulolytic microorganism has been isolated from the Verkhnee Beloe soda lake (Buryatiya, Russia) with pH 10.2 and a salt content of up to 24 g/l. Five strains were characterized. Strain Z-7026 was chosen as the type strain. The cells of the isolate are gram-positive spore-forming rods. A mucous external capsule is produced. The microorganism is obligately alkaliphilic, growing in a pH range of 8.0-10.2, with an optimum at pH 9.0. Sodium ions and, in carbonate-buffered media, sodium chloride are obligately required. The microorganism is slightly halophilic; it grows at 0.017-0.4 M Na+ with an optimum at 0.15-0.3 M Na+. The metabolism is fermentative and strictly anaerobic. Cellulose, cellobiose, and xylan can be used as growth substrates. Plant and algal debris can be fermented. Lactate, ethanol, acetate, hydrogen, and traces of formate are produced during cellulose or cellobiose fermentation. Yeast extract or vitamins are required for anabolic purposes. The microorganism fixes dinitrogen and is nitrogenase-positive. It is tolerant to up to 48 mM Na2S. Growth is not inhibited by kanamycin or neomycin. Chloramphenicol, streptomycin, penicillin, ampicillin, ampiox, bacillin, novobiocin, and bacitracin suppress growth. The DNA G+C content is 29.9 mol %. According to the nucleotide sequence of its 16S rRNA gene, strain Z-7026 is phylogenetically close to the neutrophilic cellulolytic bacteria Clostridium thermocellum (95.5%), C. aldrichii (94.9%), and Acetivibrio cellulolyticus (94.8%). It is proposed as a new species: Clostridium alkalicellum sp. nov.


Assuntos
Celulose/metabolismo , Clostridium/isolamento & purificação , Clostridium/fisiologia , Água Doce/microbiologia , Microbiologia da Água , Anaerobiose , Antibacterianos/farmacologia , Composição de Bases , Cloranfenicol/farmacologia , Clostridium/classificação , Clostridium/efeitos dos fármacos , Meios de Cultura , DNA Bacteriano/genética , Fermentação , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Nitrogenase/metabolismo , Filogenia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Federação Russa , Especificidade da Espécie , Especificidade por Substrato
17.
Mikrobiologiia ; 74(4): 520-5, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16211856

RESUMO

Phenotypic characteristics and results of PCR tests for the presence of species-specific genes indicate that a number of strains of thermophilic lactic acid bacteria previously considered as belonging to Streptococcus thermophilus are actually closely related to enterococci. In the present study, partial (over 500 nucleotides) sequencing of 16S rRNA genes from 12 strains of thermophilic lactic acid bacteria used as starters for manufacturing sour milk products on the territory of the Commonwealth of Independent States (CIS) has been performed. According to the results of the sequencing, seven of the strains have been classified with Enterococcus durans. The earlier classification (based on PCR tests) of two of the strains as S. thermophilus and three of the strains as E. faecium has been confirmed. The data obtained demonstrate that the enterococci E. durans and E. faecium are widely used as thermophilic starters for manufacturing sour milk products on the territory of the CIS.


Assuntos
Produtos Fermentados do Leite/microbiologia , Enterococcus/classificação , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Streptococcus thermophilus/classificação , Sequência de Bases , Enterococcus/genética , Microbiologia Industrial , Dados de Sequência Molecular , Fenótipo , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Streptococcus thermophilus/genética
18.
Mikrobiologiia ; 74(3): 401-9, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16119855

RESUMO

The distribution and species diversity of aerobic organotrophic bacteria in the Dagan high-temperature oil field (China), which is exploited via flooding, have been studied. Twenty-two strains of the most characteristic thermophilic and mesophilic aerobic organotrophic bacteria have been isolated from the oil stratum. It has been found that, in a laboratory, the mesophilic and thermophilic isolates grow in the temperature, pH, and salinity ranges characteristic of the injection well near-bottom zones or of the oil stratum, respectively, and assimilate a wide range of hydrocarbons, fatty acids, lower alcohols, and crude oil, thus exhibiting adaptation to the environment. Using comparative phylogenetic 16S rRNA analysis, the taxonomic affiliation of the isolates has been established. The aerobic microbial community includes gram-positive bacteria with a high and low G+C content of DNA, and gamma and beta subclasses of Proteobacteria. The thermophilic bacteria belong to the genera Geobacillus and Thermoactinomyces, and the mesophilic strains belong to the genera Bacillus, Micrococcus, Cellulomonas, Pseudomonas, and Acinetobacter. The microbial community of the oil stratum is dominated by known species of the genus Geobacillus (G. subterraneus, G. stearothermophilus, and G. thermoglucosidasius) and a novel species "Geobacillus jurassicus." A number of novel thermophilic oil-oxidizing bacilli have been isolated.


Assuntos
Bactérias Aeróbias/classificação , Petróleo/microbiologia , Bactérias Aeróbias/genética , Bactérias Aeróbias/metabolismo , Técnicas de Tipagem Bacteriana , China , Bactérias Gram-Positivas Formadoras de Endosporo/classificação , Bactérias Gram-Positivas Formadoras de Endosporo/genética , Bactérias Gram-Positivas Formadoras de Endosporo/metabolismo , Oxirredução , Petróleo/metabolismo , Filogenia , Proteobactérias/classificação , Proteobactérias/genética , Proteobactérias/metabolismo , RNA Ribossômico 16S/genética
19.
Extremophiles ; 9(3): 239-46, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15844014

RESUMO

A gram-positive, motile, strict anaerobic spore-forming bacterium was isolated from the over-cooled brine in the permafrost. The optimal temperature for isolate growth was 5-6 degrees C at pH 6.8-7.2. The bacterium was growing on the medium rich in saccharides and disaccharides. Out of polysaccharides tested, only xylan sustained the growth. Fermentation of the hexoses led to the formation of acetate, butyrate, lactate, H2,CO2 and some formate and ethanol. Cell wall peptidoglycan contained meso-diaminopimelic acid. The major fatty acids of the cell wall were C(14:0) and C(16:1c9). The content of G-C pairs in DNA was 31.4 mol%. As phylogenetic analysis has shown, it is closely linked to the members of cluster 1 of Clostridium. It differs from the other species of the genus by the substrates necessary for the growth, products forming as a result of the fermentation and content of the fatty acids in the cell wall. Thus, it was suggested to describe this strain as a new species named Clostridium algoriphilum. Type strain 14D1 was deposited into the Russian Collection of the Microorganisms VKM B-2271T and German Collection of the Microorganisms DSM 16153T .


Assuntos
Bactérias Anaeróbias/isolamento & purificação , Microbiologia da Água , Bactérias Anaeróbias/classificação , Bactérias Anaeróbias/citologia , Bactérias Anaeróbias/crescimento & desenvolvimento , Parede Celular/química , Ácidos Graxos/análise , Congelamento , Temperatura Alta , Lipídeos/análise , Polissacarídeos Bacterianos/isolamento & purificação , Esporos Bacterianos
20.
Int J Syst Evol Microbiol ; 55(Pt 1): 479-486, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15653922

RESUMO

Six strains of Gram-negative, rod-shaped, non-spore-forming bacteria were isolated from the Mediterranean Sea. 16S rRNA gene sequence analysis indicated that the strains were affiliated within the alphaproteobacterial genus Brevundimonas, with Brevundimonas intermedia (99.4 %) and Brevundimonas vesicularis (99.2 %) as their closest relatives. This affiliation was supported by chemotaxonomic data (major polar lipids: phosphatidyl diacylglycerol, sulfoquinovosyl diacylglycerol and phosphatidyl glucopyranosyl diacylglycerol; major fatty acids: C(18 : 1), C(16 : 0), C(16 : 1), C(15 : 0), C(17 : 1)omega8c, 11-Me-C(18 : 1)omega5t). The results of DNA-DNA hybridization and physiological and biochemical tests allowed genotypic and phenotypic differentiation of the strains from all recognized Brevundimonas species. The strains therefore represent a novel species, for which the name Brevundimonas mediterranea sp. nov. is proposed, with the type strain V4.BO.10T)(=LMG 21911T=CIP 107934T).


Assuntos
Caulobacteraceae/classificação , Água do Mar/microbiologia , Caulobacteraceae/química , Caulobacteraceae/genética , Caulobacteraceae/isolamento & purificação , DNA Bacteriano/análise , DNA Ribossômico/análise , Genes de RNAr , Genótipo , Mar Mediterrâneo , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
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