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1.
A strictly anaerobic, Gram-negative bacterium was isolated in continuous culture from black freshwater sediment with glycerol as sole source of carbon and energy. It was present in such sediments at 108 cells per ml. The isolate was highly specialized and used only glycerol and the glycerol residue of diolein as substrate, and fermented it quantitatively to propionate. During growth in mineral medium, small amounts of hydrogen were produced which corresponded exactly to the calculated amount of electrons released in cell matter formation from glycerol. Yeast extract enhanced cell yields with glycerol, but did not support growth itself. In cell-free extracts, benzylviologen-dependent hydrogenase activity as well as a b-type cytochrome and some of the enzymes of the methylmalonylCoA pathway were found. The guanine-plus-cytosine content of the DNA was 34.3±1.0 mol% and corresponded well with that of Anaerovibrio lipolytica which was found to be 31.4 mol%. The consequences of the electron balance of this glycerol fermentation are discussed with respect to glycerol fermentation by other propionic acid-forming bacteria.  相似文献   

2.
A new species of sporulating saccharolytic anaerobe, designated as Clostridium quinii sp. nov., is described. A gram-positive strain BS1, was isolated from the granular metanogenic sludge (UASB) from a waste-water treatment plant at a sugar refinery. The strain exhibits a series of morphological stages, developing from a spore to a small rod to a motile rod (peritrichous flagella) in the exponential growth phase, and then swelling to form cigar-shaped cells, exhibiting tumbling movements, in the late exponential growth phase before finally becoming large nonmotile ovoid cells in the stationary phase. Swelling occurs as a result of glucose being taken up and stored as a glycogen-like substance. The main fermentation products when growing on glucose is H2, CO2, formate, acetate and ethanol as well as small amounts of butyrate during exponential growth. Lactate is formed during the stationary phase, when glucose is abundant. Optimal conditions for growth is 40–45°C and pH of around 7.4. The type strain BS1 contains 28.0% mol G+C.  相似文献   

3.
Two types of new anaerobic bacteria were isolated from anoxic freshwater sediments. They grew in mineral medium with oxalate as sole energy source and with acetate as main carbon source. Oxalate as well as oxamate (after deamination) were decarboxylated to formate with growth yields of 1.2–1.4 g dry cell matter per mol oxalate degraded. No other organic or inorganic substrates were used, and no electron acceptors were reduced. Strain WoOx3 was a Gramnegative, non-sporeforming, motile vibrioid rod with a guanine-plus-cytosine content of the DNA of 51.6 mol%. It resembled the previously described genus Oxalobacter, and is described as a new species, O. vibrioformis. Strain AltOx1 was a Gram-positive, spore-forming, motile rod with a DNA base ratio of 36.3 mol% guanine-plus-cytosine. This isolate is described as a new species of the genus Clostridium, C. oxalicum.  相似文献   

4.
Strain T2–7, a 5-aminovalerate-fermenting bacterium previously classified as Clostridium aminovalericum, was further characterized, both physiologically and phylogenetically. Comparative sequencing analysis of the almost complete 16S rDNA revealed that strain T2–7 forms a distinct lineage within a phylogenetically coherent cluster of gram-positive bacteria currently assigned to the genus Clostridium. Strain T2–7 grew with 5-aminovalerate, 5-hydroxyvalerate, 4-hydroxybutyrate, vinylacetate, and crotonate, and required yeast extract and l-cysteine for growth. Other substrates were not utilized. The fermentation products, depending on the growth substrate, were ammonia, acetate, propionate, butyrate, and valerate. Sulphur was reduced by a mechanism not linked to energy conservation. Other acceptors were not utilized. Cells were gram-positive pointed-ended ovals, motile by means of two subpolar flagella, and possessed a gram-positive cell wall structure with an S-layer of hexagonally arranged subunits of 18.5 nm diameter. The DNA mol% G+C was 41.5. Strain T2–7 (DSM 6836) is proposed as the type strain of a new species, Clostridium viride sp. nov. Dedicated to H. A. Barker on the occasion of his 87th birthday  相似文献   

5.
Two new mesophilic, sporeforming, gram-positive, strictly anaerobic, rod-shaped bacteria were isolated which utilized betaine in the Stickland reaction. Strain M1 was obtained from pasteurized hypersaline sediments. Cells were motile rods and formed spherical terminal spores. Betaine was used with hydrogen and several amino acids as electron donors. In addition, several carbohydrates served as substrates. Growth required 1.5% NaCl with an optimum at 6.0% NaCl. The guanine plus cytosine content of the DNA was 26.9%. This strain is described as a new species, Clostridium halophilum.Strain W6 was isolated from marine sediments. Cells were motile rods and formed ovoid, subterminal spores. Betaine was used with hydrogen and several amino acids as electron donors. Carbohydrates were not fermented. Growth optimum was at 1.0% NaCl. The guanine plus cytosine content of the DNA was 26.1%. This strain is described as a new species, Clostridium litorale.Non standard abbreviations DMG N,N-dimethylglycine - TMA trimethylamine - PY peptone-yeast extract - PYG peptone-yeast extract-glucose  相似文献   

6.
Enrichments from an estuarine sediment with crotonate as substrate resulted in the isolation of a motile, gram-negative, obligately anaerobic rod with pointed ends, designated strain 10cr1. The organism was asporogenous, did not reduce sulfur, sulfate, thiosulfate, nitrate, oxygen or fumarate, and had a mol %G+C ratio of 29. Strain 10cr1 was able to ferment crotonate, 3-hydroxybutyrate, lactate, pyruvate, and poly--hydroxybutyric acid (PHB). Acetate, propionate, butyrate, CO2 and H2 were the fermentation products. When grown on PHB there was accumulation of 3-hydroxybutyrate once growth had ceased, indicating degradation of PHB to the monomer. The 3-hydroxybutyrate formed during growth of the culture was fermented to acetate, butyrate and H2. Experimental evidence suggested the production of an extracellular PHB depolymerase. The cells were not attached to the PHB granules. This is the first isolation of an anaerobic bacterium capable of degrading exogenous PHB. This strain is described as a new species, Ilyobacter delafieldii sp. nov., and strain 10cr1 (=DSM 5704) is designated as the type (and at present, only) strain.Abbreviations G+C guanine plus cytosine - OD optical density - PHB poly--hydroxybutyric acid - specific growth rate - HPLC high-performance liquid chromatography - YE yeast extract  相似文献   

7.
A new rod-shaped, gram-negative, non-sporeforming, strictly anaerobic bacterium (strain HHQ7) was enriched and isolated from marine mud samples with hydroxyhydroquinone (1,2,4-trihydroxybenzene) as sole substrate. Strain HHQ7 fermented hydroxyhydroquinone, pyrogallol (1,2,3-trihydroxybenzene), phloroglucinol (1,3,5-trihydroxybenzene) and gallic acid (3,4,5-trihydroxybenzoate) to 3 mol acetate (plus 1 mol CO2 in the case of gallic acid) per mol of substrate. Resorcinol accumulated intermediately during growth on hydroxy-hydroquinone. No other aliphatic or aromatic substrates were utilized. Sulfate, sulfite, sulfur, nitrate, and fumarate were not reduced with hydroxyhydroquinone as electron donor. The strain grew in sulfide-reduced mineral medium supplemented with 7 vitamins. The DNA base ratio was 59% G+C. Strain HHQ7 is classified as a new species of the genus Pelobacter, P. massiliensis. Experiments with dense cell suspensions of hydroxyhydroquinone-and pyrogallol-grown cells showed different kinetics of hydroxyhydroquinone and pyrogallol degradation, as well as different patterns of resorcinol accumulation, indicating that these substrates are metabolized by different transhydroxylation reactions.  相似文献   

8.
Enrichments on succinate plus yeast extract under anoxic conditions from intertidal mud-flat sediments yielded cultures dominated by oval to round-ended rod-shaped cells. Strain 10succ1, obtained in pure culture, was characterized in detail. The non-motile cells possessed a gram-negative cell wall and did not form spores. Carbohydrates were fermented to formate, acetate, ethanol, and lactate. Succinate was decarboxylated to propionate. Other organic and amino acids were variously fermented to formate, acetate, propionate, and butyrate. Sulfur, sulfate, thiosulfate, and nitrate were not used as electron acceptors. Growth required the presence of yeast extract and at least 5 g/l NaCl, and was possible only in the absence of oxygen. No cytochromes were detected. The DNA base ratio was 40 mol% G+C. Phylogenetically, strain 10succ1 is closely related to Propionigenium modestum, as revealed by 16S rDNA analysis, but is physiologically distinct. Accordingly, strain 10succ1 (DSM 9537) is described as the type strain of a new species of the genus Propionigenium, P. maris sp. nov. Received: 12 January 1995 / Accepted: 24 February 1995  相似文献   

9.
Four novel yeast species are described, two from decaying mushrooms, viz. Candida cretensis and Candida vadensis, and two from rotten wood, viz. Blastobotrys robertii and Candida scorzettiae. Accession numbers for the CBS and ARS Culture Collections, and GenBank accession numbers for the D1/D2 domains of the large subunit of ribosomal DNA are: B. robertii CBS 10106T, NRRL Y-27775, DQ839395; C. cretensis CBS 9453T, NRRL Y-27777, AY4998861 and DQ839393; C. scorzettiae CBS 10107T, NRRL Y-27665, DQ839394; C. vadensis CBS 9454T, NRRL Y-27778, AY498863 and DQ839396. The GenBank accession number for the ITS region of C. cretensis is AY498862 and that for C. vadensis is AY498864. C. cretensis was the only species of the four that displayed fermentative activity. All four type strains grew on n-hexadecane. C. scorzettiae is the only one of the new species that assimilates some phenolic compounds, viz. 3-hydroxy derivatives of benzoic, phenylacetic and cinnamic acids, but not the corresponding 4-hydroxy acids. This is indicative of an operative gentisate pathway.  相似文献   

10.
In a taxonomic study on the ascomycetous yeasts isolated from plant materials collected in tropical forests in Yunnan and Hainan Provinces, southern China, four strains isolated from tree sap (YJ2E(T)) and flowers (YF9E(T), YWZH3C(T) and YYF2A(T)) were revealed to represent four undescribed yeast species. Molecular phylogenetic analysis based on the large subunit (26S) rRNA gene D1/D2 domain sequences showed that strain YJ2E(T) was located in a clade together with Candida haemulonii and C. pseudohaemulonii. Strain YF9E(T) was most closely related to C. azyma and strain YWZH3C(T) to C. sorbophila and C. spandovensis. Strain YYF2A(T) was clustered in a clade containing small-spored Metschnikowia species and related anamorphic Candida species. The new strains differed from their closely related described species by more than 10% mismatches in the D1/D2 domain. No sexual states were observed for the four strains on various sporulation media. The new species are therefore assigned to the genus Candida and described as Candida alocasiicola sp. nov. (type strain, YF9E(T) = AS 2.3484(T) = CBS 10702(T)), Candida hainanensis sp. nov. (type strain, YYF2A(T) = AS 2.3478(T) = CBS 10696(T)), Candida heveicola sp. nov. (type strain, YJ2E(T) = AS 2.3483(T) = CBS 10701(T)) and Candida musiphila sp. nov. (type strain, YWZH3C(T) = AS 2.3479(T) = CBS 10697(T)).  相似文献   

11.
An obligatory anaerobic, Gram-positive, rod-shaped organism was isolated from faeces of a healthy human donor. It was characterized using biochemical, phenotypic and molecular taxonomic methods. The organism produced acetate, lactate, and ethanol as the major products of glucose fermentation. The G + C content was 53 mol%. Based on comparative 16S rRNA gene sequencing, the unidentified bacterium is a member of the Clostridium subphylum of the Gram-positive bacteria, and most closely related to species of the Clostridium coccoides cluster (rRNA cluster XIVa) [M.D. Collins et al., The phylogeny of the genus Clostridium: proposal of five new genera and eleven new species combinations, Int. J. Syst. Bacteriol. 44 (1994) 812-826]. Clostridium bolteae and Clostridium clostridioforme were identified as the most closely related described species. A 16S rRNA sequence divergence value of > 3% suggested that the isolate represents a new species. This was also supported by the gyrase-encoding gyrB gene sequences. Based on these findings, we propose the novel bacterium from human faeces to be classified as a new species, Clostridium asparagiforme. The type strain of C. asparagiforme is N6 (DSM 15981 and CCUG 48471).  相似文献   

12.
A new obligately methylotrophic bacterium (strain MTT) with the ribulose monophosphate pathway of carbon assimilation is described. The isolate, utilizing only methanol, is an aerobic, Gram-negative, asporogenous, non-motile short rod multiplying by binary fission. Its cellular fatty acids profile consists primarily of straight-chain saturated C16:0 and unsaturated C16:l acids. The major ubiquinone is Q-8. The dominant phospholipids are phosphatidylethanolamine and phosphatidylglycerol. Diphosphatidylglycerol (cardiolipin) is absent. Optimal growth conditions are 25-29 degree C, pH 6.5 - 7.5, 0.5% CH3OH and 0.05% NaCl. Strain MTT lacks alpha-ketoglutarate dehydrogenase, the glyoxylate shunt enzymes, and glutamate dehydrogenase. Ammonium is assimilated by the operation of the glutamate cycle enzymes: glutamine synthetase and glutamate synthase. An exopolysaccharide consisting of rhamnose, glucose and galactose is formed under nitrogen limitation. The G + C content of the DNA is 54.0 mol%. Based on 16S rDNA sequence analysis and DNA-DNA relatedness (29-34%) with type strains of the genus Methylophilus, the novel isolate was classified as a new species of this genus and named Methylophilus quaylei MTT (VKM B-2338T, DSMZ, etc.).  相似文献   

13.
Screening of faecal bacteria for glycyrrhetic acid (GA) production by hydrolysing of glycyrrhizin (GL) resulted in the isolation of two strains, designated ZM35T and ZM38. Strains ZM35T and ZM38 were Gram-positive, obligate anaerobic, non-spore-forming and rod-shaped bacteria. Analysis of the 16S rRNA gene sequences indicated that strains ZM35T and ZM38 belonged to cluster XIVa of the genus Clostridium. The 16S rRNA gene sequences of strains ZM35T and ZM38 were identical. Strain ZM35T exhibited approximately 94% to 95% identity with the validly described species, Clostridium oroticum(94.5%), Eubacterium contortum(93.8%), Ruminococcus gnavus(94.5%) and R. torques(95.1%). In an experiment of DNA-DNA hybridization, it was confirmed that strains ZM35T and ZM38 were the same species. The guanine-plus-cytosine (G+C) content of strain ZM35T is 45.7 mol%. Based on the phylogenetic and phenotypic findings, we propose that strains ZM35T and ZM38 be assigned to a novel species named Clostridium glycyrrhizinilyticum. The type strain is ZM35T (=JCM 13368T=DSM 17593T).  相似文献   

14.
A gram-positive, motile, rod-shaped, strictly anaerobic, sporulating bacterium was isolated from an enrichment initiated with mullet gut contents. The organism grew optimally at 30°C and pH6.5, and at a salinity of 1–103. Out of a variety of polysaccharides tested as growth substrates, only alginate supported growth in either semidefined or complex culture medium. The organism also grew on a variety of mono- and disaccharides. Moles product per 100mol of alginate monomer degraded were: acetate, 186; ethanol, 19; formate, 54; and CO2, 0.19. Moles product per 100mol of hexose in cellobiose or glucose degraded were: acetate, 135; ethanol,61; formate, 63: and CO2, 61. Hydrogen was not detectable during the incubations (detection limit, <10-5atm) and propionate, butyrate, lactate, or succinate were not produced as fermentation end products (<2 mol per 100 mol of monomer). The G+C content of DNA from the bacterium was 30.2±0.3 mol%, and the cell walls contained the peptidoglycan component meso-diaminopimelic acid. A phylogenetic analysis of the 16S rDNA sequence indicated that the organism grouped closely with members of the RNA-DNA homology group 1 of the genus Clostridium. However, it differed from other species of the genus with regard to morphology, growth temperature optimum, substrate range, and fermentation pattern and is therefore designated as a new species of Clostridium; the type strain is A-1 (DSM 8605).  相似文献   

15.
The taxonomic positions of soil isolates known as Streptomyces groups A, B and C were clarified. Comparative 16S rDNA sequence studies indicated that representatives of all three taxa formed distinct phyletic lines within the Streptomyces tree though the group A strains were shown to be related to Streptomyces griseus and associated validly described species. The taxonomic integrity of all three groups was highlighted by DNA:DNA relatedness and ribotype data though the group A strains encompassed a higher degree of genetic variation than the group B and C strains. In light of these and earlier phenotypic data it is proposed that Streptomyces groups A, B and C be given species status as Streptomyces sanglieri sp. nov., Streptomyces aureus sp. nov. and Streptomyces laceyi sp. nov., respectively. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

16.
A novel Gram-negative and rod-shaped bacterium, designated N8T, was isolated from tidal flat sediment. Phylogenetic analysis based on 16S rRNA gene sequences showed that N8T strain is associated with the family Phyllobacteriaceae: two uncultured clones (98.4 and 99.8% 16S rRNA gene sequence similarity) and the genus Mesorhizobium (≤97.0%). The novel strain formed a separate clade with uncultured clones in the phylogenetic tree based on 16S rRNA gene sequences. Cellular fatty acid profiles predominately comprised C18:1 ω7c and C19:0 cyclo ω8c. The major isoprenoid quinone is ubiquinone-10 and genomic DNA G+C content is 53.4 mol%. The polyphasic taxonomic study indicates that the novel strain N8T represents a novel species of the new genus in the family Phyllobacteriaceae, named Aliihoeflea aestuarii. The type strain is N8T (= KCTC 22052T= JCM 15118T= DSM 19536T).  相似文献   

17.
Anaerobic saccharolytic bacteria thriving at high pH values were studied in a cellulose-degrading enrichment culture originating from the alkaline lake, Verkhneye Beloye (Central Asia). In situ hybridization of the enrichment culture with 16S rRNA-targeted probes revealed that abundant, long, thin, rod-shaped cells were related to Cytophaga. Bacteria of this type were isolated with cellobiose and five isolates were characterized. Isolates were thin, flexible, gliding rods. They formed a spherical cyst-like structure at one cell end during the late growth phase. The pH range for growth was 7.5–10.2, with an optimum around pH 8.5. Cultures produced a pinkish pigment tentatively identified as a carotenoid. Isolates did not degrade cellulose, indicating that they utilized soluble products formed by so far uncultured hydrolytic cellulose degraders. Besides cellobiose, the isolates utilized other carbohydrates, including xylose, maltose, xylan, starch, and pectin. The main organic fermentation products were propionate, acetate, and succinate. Oxygen, which was not used as electron acceptor, impaired growth. A representative isolate, strain Z-7010, with Marinilabilia salmonicolor as the closest relative, is described as a new genus and species, Alkaliflexus imshenetskii. This is the first cultivated alkaliphilic anaerobic member of the Cytophaga/Flavobacterium/Bacteroides phylum.Dedicated to Prof. Dr. Hans Günter Schlegel on the occasion of his 80th birthday.  相似文献   

18.
Two thermophilic spore-forming strains, with optimum growth temperature at 70 °C, were isolated from compost of the “Experimental System of Composting” (Teora, Avellino, Italy). A phylogenetic analysis based on 16S rRNA gene sequences showed that these organisms represented a new species of the genus Geobacillus. Based on polyphasic taxonomic data the strains represented a novel species for which the name Geobacillus galactosidasius sp. nov. is proposed. The type strain is CF1BT (= ATCC BAA-1450T = DSM 18751T).  相似文献   

19.
A novel pale-yellow-pigmented, moderately halophilic, facultatively alkaliphilic, non-motile, non-spore-forming, catalase- and oxidase-positive, obligately aerobic Gram-positive coccus, strain YIM-C678T was isolated from a saline soil sample collected from a hypersaline habitat in the Qaidam basin, northwest China. The organism grew at 4–37°C and pH 6.0–11.0, with optimum growth at 25°C and pH 8.0. Strain YIM-C678T grew optimally in the presence of 10–12% (w/v) NaCl and growth was observed in 1–25% (w/v) NaCl. The cell wall murein type was l-Lys-Gly5. Major cellular fatty acids were anteiso-C15:0, iso-C15:0, iso-C16:0 and C16:0. Menaquinone 6 (MK-6) was the major respiratory quinone. The DNA G + C content was 46.5 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain YIM-C678T belonged to the family Staphylococcaceae and was most closely related to the eight described species of the genus Salinicoccus with sequence similarities from 92.2 (S. luteus YIM 70202T) to 97.5% (S. kunmingensis YIM Y15T). The DNA–DNA relatedness between strain YIM-C678T and S. kunmingensis YIM Y15T was 35.4%. Chemotaxonomic data and 16S rRNA gene sequence analysis supported the affiliation of strain YIM-C678T with the genus Salinicoccus. The combination of phylogenetic analysis, phenotypic characteristics, chemotaxonomic differences and DNA–DNA hybridization data supported the view that the bacterium represents a novel species of the genus Salinicoccus, for which the name Salinicoccus salitudinis sp. nov. is proposed, with YIM-C678T (=DSM 17846 = CGMCC 1.6299) as the type strain.  相似文献   

20.
The taxonomic position of a soil isolate, strain E626, was evaluated using the polyphasic approach. The organism was found to have chemical and morphological features consistent with its assignment to the genus Nonomuraea, a member of the family Streptosporangiaceae. Strain E626 consistently formed a distinct phyletic line within the Streptosporangiaceae 16S rDNA tree using four different algorithms. Furthermore, the taxonomic distinctness of the organism is underpinned by a range of phenotypic properties, notably morphological features. It is, therefore, proposed that the organism be classified in the genus Nonomuraea as Nonomuraea terrinata sp. nov. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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