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1.
A novel obligately aerobic heterotrophic bacterium belonging to the genus Xanthobacter, strain Z-0055, was isolated from the bacterial community of dystrophic waters formed by xylotrophic fungi grown on decaying spruce wood. The cells are small (0.4 ±0.7 fum), ovoid, grarrmegative, and nonmotile. The strain reproduces by nonuniform division. Strain Z-0055 is a moderately acidophilic microorganism and grows in a pH range of 4.8–6.8, with an optimum at pH 5.5. The temperature range for growth is 10–28°C, with an optimum at 20°C. The bacterium utilizes salts of organic acids (citrate, oxalate, succinate, and gluconate), as well as xylose and xylan as carbon and energy sources. No growth was detected at NaCl concentrations higher than 1.5 g/l. The DNA G+C base content is 63.6 mol %. According to phylogenetic analysis of the 16S rRNA gene sequences, strain Z-0055 belongs to the cluster containing X. flavus, X. aminoxidans, X. autotrophicus, and X. viscosus. The levels of similarity between the studied strain and these species are almost the same (96.0–97.0%). The genetic and ecophysiological properties of strain Z-0055 support classification of this acid-tolerant inhabitant of oligotrophic waters within the genus Xanthobacter as a new species X. xylophilus sp. nov.  相似文献   

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A polyphasic taxonomic approach was used to characterize a Gram-negative, non-motile bacterium, designated MJ15T, that was isolated from soil of a GS-Caltex Oil reservoir in Korea. As shown by comparative 16S rRNA gene sequence analysis, strain MJ15T belongs to genus Brevundimonas. The 16S rRNA gene sequence similarities ranged from 95.6–99.2% between strain MJ15T and validated representatives of the genus Brevundimonas. With respect to Brevundimonas species, strain MJ15T exhibited DNA-DNA relatedness values below 40.7%. The G+C content of the genomic DNA was 61.7 mol%. Strain MJ15T contained ubiquinone Q-10. The major fatty acids were C16:0 (27.7%), C19:0 cyclo ω8c (23.2%), summed feature 8 (containing C18:1 ω7c/C18:1 6c) (28.5%), and major hydroxyl fatty acid was C12:0 3OH (3.7%). Based upon its phenotypic and genotypic properties, as well as its phylogenetic distinctiveness, strain MJ15T (KCTC 22461T; JCM 16237T) should be classified in the genus Brevundimonas as the type strain of a novel species. The name Brevundimonas olei sp. nov. is proposed for this new species.  相似文献   

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The study isolated a Gram-negative, rod-shaped, non-motile bacterium from the soil of a ginseng field in Daejeon, South Korea and characterized it to determine its taxonomic position. Phylogenetic analysis, based on the 16S rRNA gene sequence, revealed that strain MK06T belongs to the family Xanthomonadacea, and showed the highest degree of sequence similarity to Stenotrophomonas rhizophila e-p10T (98.6%), Xanthomonas campestris LMG 568T (98.0%), Stenotrophomonas maltophilia ATCC 1d3637T (97.3%), and Stenotrophomonas humi R-32729T (96.9%). Chemotaxonomic data revealed that strain MK06T possesses ubiquinone Q-8 as the predominant respiratory lipoquinone, which is common in the genus Stenotrophomonas, and that the predominant fatty acids were 15:0 iso (41.1%), 15:0 anteiso (12.6%), and 17:1 iso ω9c (8.6%). The results of physiological and biochemical tests clearly demonstrated that strain MK06T represents a distinct species and supported its affiliation with the genus Stenotrophomonas. Based on these data, MK06T (KCTC, 22893T; JCM, 16536T; KEMB, 9004-002T) should be classified as the type strain for a novel species, for which we propose the name Stenotrophomonas panacihumi sp. nov.  相似文献   

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Two strains of purple sulfur bacteria of the family Ectothiorhodospiraceae were isolated from moderately saline steppe lakes (with pH above 9.0) of the Transbaikal region (strain B7-7) and Mongolia (strain M10). The cells of the novel strains were spiral-shaped, 2.0–3.2 × 9.6–20.0 μm, motile due to a polar tuft of flagella. Photosynthetic pigments were represented by bacteriochlorophyll a and carotenoids of the spirilloxanthin series. Photosynthetic membranes were represented by long strands of lamellae distributed throughout the whole cell; unlike most Ectothiorhodospiraceae species, the membranes were not packed into regular stacks. Bacteria were capable of weak growth on sulfide and slow grow on hydrogen under photoautotrophic conditions. The best growth was noted on sulfide in the presence of acetate and bicarbonate. Thiosulfate did not stimulate phototrophic growth, even in the presence of organic substrates. The new isolates were alkaliphiles growing at a pH optimum of 9–10. Growth was possible within a salinity range of 0–80 g/l NaCl, with an optimum at 5–15 g/l NaCl. The morphology, the structure of the photosynthetic apparatus (strands of lamellae), and the physiology of the new strains were similar to those of Thiorhodospira sibirica. However, analysis of the 16S rRNA gene sequences demonstrated that the studied isolates were closely related to the type strain Ectothiorhodospira shaposhnikovii (99% similarity) of the family Ectothiorhodospiraceae, whereas the level of similarity between the new strains and Thiorhodospira sibirica was only 94–95%. According to the results of DNA-DNA hybridization, the DNA-DNA homology level between the tested strains was almost 100%; the similarity between the new isolates and the type strain Ectothiorhodospira shaposhnikovii was only 58%. The isolates differed from other representatives of the genus Ectothiorhodospira in the structure of the gene encoding the key enzyme of autotrophic CO2 fixation, ribulose-1,5-bisphosphate carboxylase (RuBisCo), which was similar to the RuBisCo genes of members of another family of sulfur bacteria, Chromatiaceae. The new isolates of purple bacteria were described as a new species of the genus Ectothiorhodospira, Ect. magna sp. nov. with the type strain B7-7T (= VKM B-2537 = DSM 22250).  相似文献   

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A Gram-positive, moderately halophilic, facultatively alkaliphilic, catalase- and oxidase-positive, obligately aerobic, filamentous actinomycete strain, designated YIM 90022T, was isolated from saline soil collected from the Qaidam Basin, north-west China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the new isolate was a member of the genus Nocardiopsis and the sequence similarities between the isolate and the type strains of members of the genus Nocardiopsis were in the range of 95.1–98.7%. Phenotypic and chemotaxonomic properties of this organism also indicated that strain YIM 90022T was a member of the genus Nocardiopsis. The strain grew well on most of the media tested, producing yellow-white to deep brown substrate mycelium and white aerial mycelium. Light gray to deep brown diffusible pigments were produced. The substrate mycelium was well developed and fragmented with age; the aerial mycelium produced long, straight to flexuous spore chains with non-motile, smooth-surfaced, rod-shaped spores on them. The strain grew in the presence of 1–15% (w/v) total salts (optimum, 3–5%) and at pH 6.0–10.5 (optimum, pH 8.5) and 10–45°C (optimum, 30°C). Whole-cell hydrolysates of strain YIM 90022T contained meso-diaminopimelic acid and no diagnostic sugars. The predominant menaquinones were MK-10(H4), MK-9(H8), MK-10(H6) and MK-10(H8). Polar lipids comprised diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol and phosphatidylmethylethanolamine. The major cellular fatty acids were iso-C16:0, anteiso-C17:0, 10-methyl-C18:0 and 10-methyl-C17:0. The DNA G + C content of strain YIM 90022T was 71.5 mol%. The combination of phylogenetic analysis, DNA–DNA relatedness data, phenotypic characteristics and chemotaxonomic data supported the suggestion that strain YIM 90022T represents a new species of the genus Nocardiopsis, for which the name Nocardiopsis terrae sp. nov. is proposed. The type strain is YIM 90022T (=CCTCC AA 208011T =KCTC 19431T).  相似文献   

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The causal fungus of Ceratocystis canker of fig in Japan is described as Ceratocystis ficicola sp. nov. This species is characterized by galeated ascospores and is similar to Ceratocystis fimbriata sensu lato. However, the perithecia of the new species are much larger than those of C. fimbriata. The fungus grows more rapidly than C. fimbriata sensu stricto at 25°C but more slowly at 30°C. Molecular analysis of the nucleotide sequences of rDNA ITS regions showed that C. ficicola is phylogenetically placed in the clade of C. fimbriata s. l. but is easily distinguishable from other species of C. fimbriata s. l.  相似文献   

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Oil-polluted soils were sampled from National Iranian South Oil Company (NISOC) for isolation and screening of C–S and not C–C targeted Dibenzothiophene (DBT) degrading microorganisms. Microbacterium sp. NISOC-06, a C–S targeted DBT degrading bacterium, was selected and its desulfurization ability was studied in aqueous phase and water-gasoline biphasic systems. The 16srRNA gene was amplified using universal eubacteria-specific primers, PCR product was sequenced and the sequence of nearly 1,500 bp 16srDNA was studied. Based on Gas Chromatography results Microbacterium sp. NISOC-06 utilized 94.8% of 1 mM DBT during the 2 weeks of incubation. UV Spectrophotometry and biomass production measurements showed that the Microbacterium sp. NISOC-06 was not able to utilize DBT as a carbon source. There was no accumulation of phenolic compounds as Gibb’s assay showed. Biomass production in a biphasic system for which DBT-enriched gasoline was used as the sulfur source indicated the capability of Microbacterium sp. NISOC-06 to desulfurize gasoline.  相似文献   

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The hydrodynamic characteristics of dioxane lignin diluted solutions prepared from straw of rye Secale sp. and barley Hordeum sp. have been studied. The interrelation of hydrodynamic and fractal characteristics of polymers have been considered. It is shown that macromolecules of lignines have a linear topological structure.  相似文献   

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Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this disease.  相似文献   

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Introduction  

SPARC is a matricellular protein, which, along with other extracellular matrix components including collagens, is commonly over-expressed in fibrotic diseases. The purpose of this study was to examine whether inhibition of SPARC can regulate collagen expression in vitro and in vivo, and subsequently attenuate fibrotic stimulation by bleomycin in mouse skin and lungs.  相似文献   

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Interaction of Bdellovibrio bacteriovorus 100NCJB with bacteria Campylobacter jejuni (strains 1, 2, 3, 4, and 5) and Helicobacter pylori, strain TX30a, was confirmed. The results indicate that lytic activity of bdellovibrios both in liquid media and cells attached to a surface was observed. The potential use of the antimicrobial activity of predatory bacteria for environmental bioprotection and public health is discussed.  相似文献   

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A Gram-stain negative, ovoid or short rod-shaped, aerobic and non-motile bacterial strain, designated J82T, was isolated from a seawater sample collected from the coast of Yellow Sea in Qingdao, China. The strain grew at salinities of 1.0–6.0% (w/v) NaCl (optimum, 2.5%). Growth occurred at pH 6.0-8.0 (optimum, pH 7.0) and 10–42 °C (optimum, 28–30 °C). The genomic DNA G + C content was determined to be 57.5 mol%. Q-10 was detected as the respiratory quinone. The major fatty acid (>10%) was Summed feature 8 (C18:1 ω7c and/or C18:1 ω6c). The polar lipids consisted of phosphatidylethanolamine, two unidentified aminolipids and two unidentified polar lipids. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain J82T forms a distinct evolutionary lineage within the family Rhodobacteraceae. On the basis of phenotypic, chemotaxonomic and phylogenetic characteristics, the strain merits recognition as representative of a novel genus and species within the family Rhodobacteraceae for which the name Rubricella aquisinus gen. nov., sp. nov. is proposed. The type strain of Rubricella aquisinus is J82T (= DSM 103377T = CCTCC AB 2016170T).  相似文献   

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Allophycocyanin (APC) is a minor component of phycobiliproteins in cyanobacteria and red algae. This paper describes a simple and inexpensive extracting method for isolating APC from Spirulina (Arthrospira) platensis with high efficiency. The crude phycobiliprotein extract was pretreated by ammonium sulfate fractionation. Then, by adding hydroxylapatite into crude phycobiliprotein extract dissolved in 20 mM phosphate buffer (pH 7.0), APC was selectively adsorbed by hydroxylapatite but C-phycocyanin (C-PC) was not. The hydroxylapatite was collected and APC was extracted from the crude phycobiliprotein extract. Then, the enriched APC was washed off from the hydroxylapatite using 100 mM phosphate buffer (pH 7.0). In this simple extracting method it was easy to remove C-PC and isolate APC in large amounts. The absorbance ratio A 650/A 280 of extracted APC reached 2.0. The recovery yield was 70%, representing 4.61 mg · g−1 wet weight. The extracted APC could be further purified by a simple anion-exchange chromatography with a pH gradient from 5.6 to 4.0. The absorbance ratio A 650/A 280 of the purified APC reached 5.0, and the overall recovery yield was 43%, representing 2.83 mg · g−1 wet weight. Its purity was confirmed by native polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate-PAGE.  相似文献   

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Passiflora alata in vitro organogenesis was studied based on explant type, culture medium composition, and incubation conditions. The results indicated that the morphogenic process occurred more efficiently when hypocotyl segment-derived explants were cultured in media supplemented with cytokinin and AgNO3 incubated under a 16-h photoperiod. The shoot bud elongation and plant development were obtained by transferring the material to MSM culture medium supplemented with GA3 and incubated in flasks with vented lids. Histological analyses of the process revealed that the difficulties in obtaining plants could be related to the development of protuberances and leaf primordia structures, which did not contain shoot apical meristem. Roots developed easily by transferring elongated shoots to 1/2 MSM culture medium. Plant acclimatization occurred successfully, and somaclonal variation was not visually detected. The efficiency of this organogenesis protocol will be evaluated for genetic transformation of this species to obtain transgenic plants expressing genes that can influence the resistance to Cowpea aphid borne mosaic virus.  相似文献   

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