首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
During dismantling and relocation of the Takamatsuzuka Tumulus stone chamber, many Cladophialophora and chaetothyrialean black fungi, such as Exophiala and Phialophora, were isolated from samples taken from the joints between the stone walls. However, inside the stone chamber of the Kitora Tumulus, after intermittent UV irradiation in 2009, these black fungi were also isolated from samples taken from the stone walls. Molecular phylogenetic analyses based on only nrLSU and the concatenated (nrLSU D1/D2 + ITS) sequences revealed that the 35 Takamatsuzuka and Kitora Tumuli isolates of Cladophialophora and the chaetothyrialean black fungi were divergent. Two new species of Cladophialophora are described herein: C. tumulicola from the viscous gels and various substrates on the stone walls of the Takamatsuzuka and Kitora Tumuli and C. tumbae from black substances on the plastic cover over the “thief hole,” soil and plaster pieces between the stone walls, and the exterior of the Takamatsuzuka Tumulus chamber. Also, molecular phylogenetic placements for the remaining eight Takamatsuzuka and Kitora Tumuli isolates of chaetothyrialean black fungi have been determined or suggested.  相似文献   

2.
A taxonomic study was conducted on 16 bacterial strains isolated from wild Adélie penguins (Pygoscelis adeliae) from Seymour (Marambio) Island and James Ross Island. An initial screening by repetitive sequence-based PCR fingerprinting divided the strains studied into four coherent groups. Phylogenetic analysis based on 16S rRNA gene sequences assigned all groups to the genus Corynebacterium and showed that Corynebacterium glyciniphilum and Corynebacterium terpenotabidum were the closest species with 16S rRNA gene sequence similarities between 95.4 % and 96.5 %. Further examination of the strains studied with ribotyping, MALDI-TOF mass spectrometry, comprehensive biotyping and calculation of average nucleotide identity and digital DNA–DNA hybridisation values confirmed the separation of the four groups from each other and from the other Corynebacterium species. Chemotaxonomically, the four strains P5828T, P5850T, P6136T, P7210T representing the studied groups were characterised by C16:0 and C18:1 ω9c as the major fatty acids, by the presence of meso-diaminopimelic acid in the peptidoglycan, the presence of corynemycolic acids and a quinone system with the predominant menaquinone MK-9(H2). The results of this study show that the strains studied represent four new species of the genus Corynebacterium, for which the names Corynebacterium antarcticum sp. nov. (type strain P5850T = CCM 8835T = LMG 30620T), Corynebacterium marambiense sp. nov. (type strain P5828T = CCM 8864T = LMG 31626T), Corynebacterium meridianum sp. nov. (type strain P6136T = CCM 8863T = LMG 31628T) and Corynebacterium pygosceleis sp. nov. (type strain P7210T = CCM 8836T = LMG 30621T) are proposed.  相似文献   

3.
Worldwide glaciers are annually retreating due to global overheating and this phenomenon determines the potential lost of microbial diversity represented by psychrophilic microbial population sharing these peculiar habitats. In this context, yeast strains, all unable to grow above 20°C, consisting of 42 strains from Antarctic soil and 14 strains isolated from Alpine Glacier, were isolated and grouped together based on similar morphological and physiological characteristics. Sequences of the D1/D2 and ITS regions of the ribosomal DNA confirmed the previous analyses and demonstrated that the strains belong to unknown species. Three new species are proposed: Mrakia robertii sp. nov. (type strain CBS 8912), Mrakia blollopis sp. nov. (type strain CBS 8921) and a related anamorphic species Mrakiella niccombsii sp. nov. (type strain CBS 8917). Phylogenetic analysis of the ITS region revealed that the new proposed species were closely related to each other within the Mrakia clade in the order Cystofilobasidiales, class Tremellomycetes. The Mrakia clade now contains 8 sub-clades. Teliospores were observed in all strains except CBS 8918 and for the Mrakiella niccombsii strains.  相似文献   

4.
Isolates AH11T and AH13T were isolated from flowers of lantana and candle bush respectively collected in Thailand. In phylogenetic trees based on 16S rRNA gene sequences, the two isolates formed an independent cluster, which was then connected to the type strain of Saccharibacter floricola. The calculated pair-wise 16S rRNA gene sequence similarities of isolate AH11T were 95.7–92.3% to the type strains of the type species of the 12 genera of acetic acid bacteria. The DNA base composition was from 51.2 to 56.8 mol % G+C, with a range of 5.6 mol %. When isolate AH11T was labeled, DNA-DNA similarities were 100, 12, 4, 5, and 4% respectively to isolates AH11T and AH13T and the type strains of Saccharibacter floricola, Gluconobacter oxydans, and Acetobacter aceti. The two isolates were non-motile and did not oxidize either acetate or lactate. No growth was found in the presence of 0.35% acetic acid w/v. The two isolates were not osmophilic but osmotolerant, produced 2,5-diketo-D-gluconate from D-glucose, and did not oxidize lactate, thus differing from strains of Saccharibacter floricola, which showed weak lactate oxidation. The two isolates contained unsaturated C18:1ω7c fatty acid as the major fatty acid, and were unique in the presence of a considerable amount of straight-chain C18:12OH fatty acid. Q-10 was present as the major isoprenoid quinone. Neokomagataea gen. nov. was proposed with the two species, Neokomagataea thailandica sp. nov. for isolate AH11T (=BCC 25710 T =NBRC 106555T), which has 56.8 mol % G+C, and Neokomagataea tanensis sp. nov. for isolate AH13T (=BCC 25711T=NBRC 106556T), which has 51.2 mol % G+C.  相似文献   

5.
Isolates AH11(T) and AH13(T) were isolated from flowers of lantana and candle bush respectively collected in Thailand. In phylogenetic trees based on 16S rRNA gene sequences, the two isolates formed an independent cluster, which was then connected to the type strain of Saccharibacter floricola. The calculated pair-wise 16S rRNA gene sequence similarities of isolate AH11(T) were 95.7-92.3% to the type strains of the type species of the 12 genera of acetic acid bacteria. The DNA base composition was from 51.2 to 56.8 mol % G+C, with a range of 5.6 mol %. When isolate AH11(T) was labeled, DNA-DNA similarities were 100, 12, 4, 5, and 4% respectively to isolates AH11(T) and AH13(T) and the type strains of Saccharibacter floricola, Gluconobacter oxydans, and Acetobacter aceti. The two isolates were non-motile and did not oxidize either acetate or lactate. No growth was found in the presence of 0.35% acetic acid w/v. The two isolates were not osmophilic but osmotolerant, produced 2,5-diketo-D-gluconate from D-glucose, and did not oxidize lactate, thus differing from strains of Saccharibacter floricola, which showed weak lactate oxidation. The two isolates contained unsaturated C(18:1)ω7c fatty acid as the major fatty acid, and were unique in the presence of a considerable amount of straight-chain C(18:1)2OH fatty acid. Q-10 was present as the major isoprenoid quinone. Neokomagataea gen. nov. was proposed with the two species, Neokomagataea thailandica sp. nov. for isolate AH11(T) (=BCC 25710(T)=NBRC 106555(T)), which has 56.8 mol % G+C, and Neokomagataea tanensis sp. nov. for isolate AH13(T) (=BCC 25711(T)=NBRC 106556(T)), which has 51.2 mol % G+C.  相似文献   

6.
Two new yeast species of the genus Ambrosiozyma are described on the basis of comparison of nucleotide sequences of large subunit of ribosomal DNA D1/D2 region. Ambrosiozyma kamigamensis and Ambrosiozyma neoplatypodis differ from Ambrosiozyma ambrosiae by 17 nucleotides (3.0%) and 16 nucleotides (2.8%), respectively, out of 565. The two species differ from each other by 13 nucleotides. Ambrosiozyma kamigamensis was isolated from galleries of the ambrosia beetle, Platypus quercivorus, in specimens of Quercus laurifolia and Castanopsis cuspidata located in the southern part of Kyoto, Japan. Ambrosiozyma neoplatypodis was isolated from similar material, but only in Q. laurifolia. Ambrosiozyma kamigamensis can be distinguished from the other Ambrosiozyma species by the inability to assimilate erythritol, whereas A. neoplatypodis can be distinguished by the ability to assimilate both L: -arabinose and nitrate. The type strains of A. kamigamensis and A. neoplatypodis are JCM 14990(T) (=CBS 10899(T)) and JCM 14992(T) (=CBS 10900(T)), respectively. This is the first report of new Ambrosiozyma species since the genus was proposed.  相似文献   

7.
An amoeba strain was isolated from marine sediment taken from the beach near a fumarole in Italy. The trophozoites of this new marine species transforms into flagellates with variable numbers of flagella, from 2 to 10. The strain forms round to oval cysts. This thermophilic amoeboflagellate grows at temperatures up to 54 °C. Molecular phylogenetic analysis of the small subunit ribosomal DNA (SSU rDNA) places the amoeboflagellate in the Heterolobosea. The closest relatives are Stachyamoeba sp. ATCC50324, a strain isolated from an ocean sample, and Vrihiamoeba italica, a recent isolate from a rice field. Like some other heterolobosean species, this new isolate has a group I intron in the SSU rDNA. Because of the unique place in the molecular phylogenetic tree, and because there is no species found in the literature with similar morphological and physiological characteristics, this isolate is considered to be a new genus and a new species, Oramoeba fumarolia gen. nov., sp. nov.  相似文献   

8.
Ougandatherium napakense nov. gen. nov. sp., the earliest Rhinocerotidae Iranotheriinae from Africa. The Uganda Palaeontology Expedition discovered an exceptionally rich fossiliferous channel deposit at Napak I, Karamoja, in 1999, which yielded two partial skeletons of a new genus and species of early Miocene Rhinocerotidae, together with various other mammals and gastropods typical of Faunal Set I of East Africa. The age of the deposits on the basis of both faunal correlation (biochronology) and radio-isotopic dating is ca 19–20 Ma. The new genus and species is a hornless rhinoceros about the size of a small horse, with long slender limb bones and metapodials and hypsodont upper cheek teeth whose enamel is undulate, and fossettes cement-filled. Upper premolars possess an inner wall; this is clearly an iranotheriine morphology. As such it is the earliest known African member of this subfamily, close to the oldest member of the subfamily recently discovered at Bugti in Pakistan, a site whose age is about the same.  相似文献   

9.
10.
A novel group of hyperthermophilic rod-shaped motile methanogens was isolated from a hydrothermally heated deep sea sediment (Guaymas Basin, Gulf of California) and from a shallow marine hydrothermal system (Kolbeinsey ridge, Iceland). The grew between 84 and 110°C (opt: 98°C) and from 0.2% to 4% NaCl (opt. 2%) and pH 5.5 to 7 (opt: 6.5). The isolates were obligate chemolithoautotrophes using H2/CO2 as energy and carbon sources. In the presence of sulfur, H2S was formed and cells tended to lyse. The cell wall consisted of a new type of pseudomurein containing ornithin in addition to lysine and no N-acetylglucosamine. The pseudomurein layer was covered by a detergent-sensitive protein surface layer. The core lipid consisted exclusively of phytanyl diether. The GC content of the DNA was 60 mol%. By 16S rRNA comparisons the new organisms were not related to any of the three methanogenic lineages. Based on the physiological and molecular properties of the new isolates, we describe here a new genus, which we name Methanopyrus (the methane fire). The type species is Methanopyrus kandleri (type strain: AV19; DSM 6324).This paper is dedicated to Otto Kandler on the occasion of his 70th birthday  相似文献   

11.
Among about 500 strains tested, a newly isolated soil bacterium, Brevibacterium sterolicum nov. sp. KY 3463 (ATCC 21387) showed the highest potency in production of 3β-hydroxysteroid oxidase in the culture fluid.

The 3β-hydroxysteroid oxidase was purified from the culture filtrate by a procedure involving ammonium sulfate fractionation, DEAE-cellulose and hydroxyapatite column chromatographies and Sephadex G–75 gel filtration. Crystals of the enzyme were obtained from solutions of the purified preparation by the addition of ammonium sulfate. The crystals appeared as fine rods, with a bright yellow color.

The enzyme is homogeneous by disc gel electrophoresis and ultracentrifugation. Sedimentation velocity yields a value of . It exhibits a typical flavoprotein spectrum of absorption maxima at 280, 390, and 470 mμ.  相似文献   

12.
Two new Ulvella species, U. elegans R. Nielsen & K. Gunnarsson and U. islandica R. Nielsen & K. Gunnarsson are described. These microfilamentous marine green algae were found in the sublittoral zone in northern Iceland, epiphytic on Euthora cristata and associated with a calcareous polychaete tube, respectively. Unialgal cultures were established from field-collected material for morphological observations. In culture, Ulvella elegans was characterized by rosettes of monostromatic pseudoparenchyma consisting of radiating filaments with a margin of mutually free filaments. Each cell had one pyrenoid. Hairs were not observed. Ulvella islandica had a heterotrichous morphology, consisting of dense tufts of upright broad branches and much narrower, rhizoid-like branches. Acrochaete-type hairs occurred; these are hyaline non-septate merocytic extensions from a more or less bulbous base, which may be separated from the vegetative cell below. Most cells had one pyrenoid except for a few broad cells which had two or three. In a phylogenetic reconstruction based on the chloroplast-encoded tufA gene, the sequences for the two species were clearly distinct from any other Ulvella sequence available for this gene. Ulvella islandica was placed in a clade together with U. lens, U. wittrockii, U. reticulata and U. pseudorepens. Ulvella elegans occupied a branch deep in the phylogeny but the position was poorly supported.  相似文献   

13.
A new toxin-producing marine diatom, Nitzschia bizertensis sp. nov., isolated from the Bizerte Lagoon (Tunisia, Southwest Mediterranean Sea) is, based on studies on eight different strains, characterized morphologically by light microscopy, transmission and scanning electron microscopy, and phylogenetically using the nuclear rDNA regions: SSU, ITS1, 5.8S, ITS2 and D1–D3 of the LSU. The species belongs to the sections Lanceolatae or Lineares as defined by Cleve and Grunow (1880). These sections are characterized by species having linear-lanceolate valves with an eccentric raphe where the fibulae does not extend into the valve, and are otherwise famous for the lack of characters useful for delineation of species. Nitzschia bizertensis differs from most other species in these sections by having a high density of interstriae. The morphological and phylogenetic studies and comparisons with previously described Nitzschia species showed Nitzschia bizertensis sp. nov. to be a new species. Batch culture experiments were conducted for estimations of maximum growth rate and production of domoic acid (DA). Maximum cellular DA content of the examined strains ranged from 2 × 10−4 to 3.6 × 10−2 pg cells−1. The total DA concentration (pg mL−1) was high already in exponential growth phase maybe due to reinoculation of “old” stationary phase cells, and increased into stationary growth phase where it reached a stationary level varying among the strains from ca. 4500 to 9500 pg mL−1. Nitzschia bizertensis represents a new domoic acid-producing diatom and is the second toxin producing Nitzschia species. The resolution of Nitzschia bizertensis and Nitzschia navis-varingica in different parts of the LSU phylogenetic tree, and the recovery of the Pseudo-nitzschia species phylogenetically distant from those two species suggests that the ability to produce DA either evolved multiple times independently or was lost multiple times.  相似文献   

14.
The present paper deals with the cuticular structure of Rhaphidopteris hsüi sp. nov. The specimens were collected from the Upper Triassic cos series of Liuzhi district, Guizhou Province. Based on the shape and cuticular structure of leaf and segments, this new species is assigned to Corystospermaceae of Cycadofilicales. According to the assemblage of the fossil plants, the writers consider that the geological age of this flora is assigned to the middle Keuper-Rhaetic stage of Late Triassic.  相似文献   

15.
A new species of Hypoxylon was discovered, based on material collected in French Guiana and recognised on the basis of new combination of morpholological characters in comparison with type and authentic material of macroscopically similar taxa. These findings were corroborated by the rather isolated positions of its ITS-nrDNA and beta-tubulin DNA sequences in molecular phylogenies. However, the most salient feature of this fungus only became evident by a comparison of its stromatal HPLC profile, revealing several secondary metabolites that were hitherto not observed in stromata of any other member of the Xylariaceae. Part of the stromata were subsequently extracted to isolate these apparently specific components, using preparative chromatography. Five metabolites were obtained in pure state, and their chemical structures were elucidated by means of high resolution mass spectrometry and nuclear magnetic resonance spectroscopy. They turned out to be tetramic acid derivatives of the so-called vermelhotin type. Aside from vermelhotin, previously isolated from cultures of endophytic fungi, we identified three novel congeners, for which the trivial names hypoxyvermelhotins A–C were proposed. Like vermelhotin, they constitute orange-red pigments and a preliminary biological characterisation revealed them to have rather strong cytotoxic and moderate to weak antimicrobial effects. These results further illustrate the high diversity of unique secondary metabolites in stromata of the hypoxyloid Xylariaceae, a family in which biological diversity seems to parallel the chemical diversity of their bioactive principles to a great extent.  相似文献   

16.
何桂铭 《昆虫学报》1963,(3):368-371
在1957年7月,作者在广州市郊夏收后稻田积水,采集库蚊幼虫一批,经隔离培养获得羽化成虫、蛹皮及幼虫皮,另保存四龄幼虫一批,经研究后认为是库蚊属的一新种。现将其中雌蚊10个,雄蚊9个及其幼虫皮,并将幼虫形态描述如下: 一、成虫 雌蚊 头部复盖有淡色至棕色弯窄鳞及直竖叉状鳞片,头顶部两侧有扁平淡色鳞  相似文献   

17.
Two isolates, AC04T and AC05, were isolated from the flowers of red ginger collected in Chiang Mai, Thailand. In phylogenetic trees based on 16S rRNA gene sequences, the two isolates were included within a lineage comprised of the genera Acidomonas, Gluconacetobacter, Asaia, Kozakia, Swaminathania, Neoasaia, Granulibacter, and Tanticharoenia, and they formed an independent cluster along with the type strain of Tanticharoenia sakaeratensis. The calculated pair-wise sequence similarities of isolate AC04T were 97.8–92.5% to the type strains of the type species of the 11 genera of acetic acid bacteria. The DNA base composition was 66.0–66.1 mol % G+C with a range of 0.1 mol %. A single-stranded, labeled DNA from isolate AC04T presented levels of DNA-DNA hybridization of 100, 85, 4, and 3% respectively to DNAs from isolates AC04T and AC05 and the type strains of Tanticharoenia sakaeratensis and Gluconacetobacter liquefaciens. The two isolates were unique morphologically in polar flagellation and physiologically in intense acetate oxidation to carbon dioxide and water and weak lactate oxidation. The intensity in acetate oxidation almost equaled that of the type strain of Acetobacter aceti. The two isolates had Q-10. Isolate AC04T was discriminated from the type strains of the type species of the 11 genera by 16S rRNA gene restriction analysis using restriction endonucleases TaqI and Hin6I. The unique phylogenetic, genetic, morphological, physiological, and biochemical characteristics obtained indicate that the two isolates can be classified into a separate genus, and Ameyamaea chiangmaiensis gen. nov., sp. nov. is proposed. The type strain is isolate AC04T (=BCC 15744T, =NBRC 103196T), which has a DNA G+C content of 66.0 mol %.  相似文献   

18.
凤眼莲根分泌物对Enterobacter sp.nov.苯酚代谢的影响   总被引:11,自引:6,他引:5  
本文利用从含酚废水中筛选出新的高效降酚菌株(Enterobacter sp.nov.)和凤眼莲根分泌物来探讨风眼莲与细菌之间松散的、非特异性的降酚机理。研究了风眼莲分泌物及其不同的组分对Enterobacter sp.nov.生长、降酚酶活性和降酚效率的影响。结果表明,低浓度的根分泌物(≤1%V/V)促进细菌生长,提高降酚效率,而高浓度的根分泌物(≥10%V/V)虽能促进细菌生长,但会抑制细菌降酚酶的诱导,降低降酚效率。凤眼莲根分泌物各组分中还原糖是影响Enterobacter sp.nov.降酚的关键因子。提出了人工组建凤眼莲和Enterobacter sp.nov.系统,提高降酚效率的可能性。  相似文献   

19.
Rossmania ukurunduensis gen. and sp. nov. collected in the reverve Bolshekhekhtsirsky (Khabarovsk Territory, Russian Far East) is described and illustrated.Rossmania aculeata comb. Nov. is indicated as the second species of the genus.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号