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1.
A succinate-mineral salts medium of pH 5.2 provided selective enrichment conditions for Rhodomicrobium vannielii and for a new species belonging to the Athiorhodaceae, described herein as Rhodopseudomonas acidophila. Seven strains of the new species have been isolated from different sources in the United States and Germany. The cells are rod-shaped or ovoid, 1.0 to 1.3 μm wide and 2 to 5 μm long, and motile by means of polar flagella. Multiplication occurs by budding. The photopigments consist of bacteriochlorophyll a and carotenoids of the spirilloxanthin series, together with new carotenoids. All strains can grow either under anaerobic conditions in the light or under microaerophilic to aerobic conditions in the dark. No growth factors are required. The range of simple organic substrates photo-assimilated resembles that characteristic of Rhodomicrobium. Good photolithotrophic growth is possible at the expense of molecular hydrogen; thiosulfate and sulfide are not utilized.  相似文献   

2.
Five strains of thermotolerant methylotrophic yeasts isolated in Thailand were found to represent three new species in the genera Pichia and Candida, based on phylogenetic analysis of D1/D2 domain of 26S rDNA, in addition to the morphological, physiological, biochemical and chemotaxonomic characterization. Three strains, FS96 and FS101 from flowers and M02 from tree flux, were characterized by ubiquinone Q7, multilateral budding, and the formation of hat-shaped ascospores that are liberated at maturation. These strains showed identical nucleotide sequences in the D1/D2 domain and formed a cluster with Candida thermophila, "Pichia salicis" and Pichia angusta. They differed by 1.9% of nucleotide substitutions from Candida thermophila, the nearest species. They were considered to represent a single new species and are described as Pichia siamensis sp. nov. Two strains, N051 and S023, isolated from soil did not produce ascospores, proliferated by multilateral budding, did not demonstrate urease or DBB color reaction, and lacked sexual stages. These characteristics correspond to the genus Candida. Strains N051 and S023 differed by 2.8% and 1.9% of nucleotide substitutions in the D1/D2 domain from the nearest species, Candida nemodendra and Candida ovalis, respectively, and are considered to represent respective new species. N051 and S023 are described as Candida krabiensis sp. nov. and Candida sithepensis sp. nov., respectively.  相似文献   

3.
Two isolates, with an optimum growth temperature of about 45–50 °C and an optimum pH for growth between 7.5 and 8.5, were recovered from a hot spring in the Furnas area on the Island of São Miguel in the Azores. Strains form irregular rod-shaped cells are motile and stain Gram negative. The cells multiply by budding. These strains are non-pigmented, strictly aerobic, catalase and oxidase positive. These organisms assimilated carbohydrates, organic acids and amino acids. The major fatty acids are 19:0cyclo ω8c and 18:0. Ubiquinone 10 is the major respiratory quinone. The major polar lipids are diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine in addition to one unidentified aminolipid and one unidentified glycolipid. Bacteriochlorophyll a, puf genes and RuBisCo genes were not detected. Analysis of the 16S rRNA gene shows the strains to cluster with species of the genera Afifella, Rhodobium, Anderseniella and Amorphus to which they have sequence similarity in the range 93–94%. Based on 16S rRNA gene sequence analysis, physiological and biochemical characteristics we describe a new species of a novel genus represented by strain CB-27AT (=DSM 19345T=LMG 24113T) for which we propose the name Tepidamorphus gemmatus.  相似文献   

4.
Two moderately halophilic and psychrotolerant new Mycoplasma species were isolated from common cephalopods. Three strains were isolated in pure culture from two individual European flying squid (Todarodes sagittatus), and two individual octopuses (Octopus vulgaris). The strains showed optimal growth at 25 °C and a salinity of 3% (w/v) NaCl. Molecular analyses revealed that the isolates belonged to two new, but phylogenetically related species, divergent from all previously described Mollicutes, representing the first marine isolates of the class, and also the first Mycoplasma strains for which NaCl requirement has been demonstrated. A genome search against all available marine metagenomes and 16S rRNA gene databases indicated that these two species represent a novel non-free-living marine lineage of Mollicutes, specifically associated with marine animals. Morphology and physiology were compatible with other members of this group, and genomic and phenotypic analyses demonstrated that these organisms represent two novel species of the genus Mycoplasma, for which the names Mycoplasma marinum sp. nov. and Mycoplasma todarodis sp. nov. are proposed; the type strains are PET (DSM 105487T, CIP 111404T) and 5HT (DSM 105,488T, CIP 111405T), respectively.  相似文献   

5.
Polyakova  A. V.  Chernov  I. Yu. 《Microbiology》2002,71(3):331-334
Five anamorphous yeast strains of ascomycetous affinity with a specific mode of budding were isolated from high bog soils of the Bakcharskoe Bog (Tomsk oblast). According to their morphological and physiological properties, these strains belong to the genus Candida but differ from all species described previously. The level of DNA–DNA homology with species similar in the assimilation spectrum was as low as 7%. Based on these data, the new species Candida aurita sp. nov. is described.  相似文献   

6.
Seven strains of ballistoconidiogenous yeasts that contain xylose, form Q-10 ubiquinone, propagate by budding and don't produce stalk conidia were isolated from plant leaves collected in Thailand and were found to represent two new species. The taxonomic properties of the two species coincided with the genus Bullera so they are described as Bullera koratensis sp. nov. and Bullera lagerstroemiae sp. nov. In phylogenetic trees based on the nucleotide sequences of 18S ribosomal DNA and the D1/D2 domain of 26S rDNA, these two species are located in the Trichosporonales clade (Cryptococcus humicola-Trichosporon lineage).  相似文献   

7.
The family Chlamydiaceae with the recombined single genus Chlamydia currently comprises nine species, all of which are obligate intracellular organisms distinguished by a unique biphasic developmental cycle. Anecdotal evidence from epidemiological surveys in flocks of poultry, pigeons and psittacine birds have indicated the presence of non-classified chlamydial strains, some of which may act as pathogens. In the present study, phylogenetic analysis of ribosomal RNA and ompA genes, as well as multi-locus sequence analysis of 11 field isolates were conducted. All independent analyses assigned the strains into two different clades of monophyletic origin corresponding to pigeon and psittacine strains or poultry isolates, respectively. Comparative genome analysis involving the type strains of currently accepted Chlamydiaceae species and the designated type strains representing the two new clades confirmed that the latter could be classified into two different species as their average nucleotide identity (ANI) values were always below 94%, both with the closest relative species and between themselves.  相似文献   

8.
Five anamorphous yeast strains of ascomycetous affinity with a specific mode of budding were isolated from raised bog soils of Bakcharskoe Bog (Tomsk oblast). According to their morphological and physiological properties, these strains belong to the genus Candida but differ from all species described previously. The level of DNA-DNA homology with species similar in the assimilation spectrum was as low as 7%. Based on these data, the new species Candida aurita sp. nov. is described.  相似文献   

9.
Strains 19SMN4T and ST27MN3 were isolated from marine sediments after enrichment with 2-methylnaphthalene and were classified as Pseudomonas stutzeri genomovar 4. Four other strains, BG 2, HT20, HT24, and A7, were isolated from sulphide-oxidizing bioreactors or activated sludge affiliated with the same clade in the 16S rRNA phylogenetic tree. P. stutzeri has been recently reclassified as a new genus, Stutzerimonas, and a preliminary analysis indicated that the strains in this study were distinct from any classified Stutzerimonas and are considered representatives of phylogenomic species 4 (pgs4). Strains 19SMN4T and ST27MN3 were extensively characterized with phenotypic, chemotaxonomic, genomic and phylogenomic data. Strain 19SMN4T had a well-characterized naphthalene degradative plasmid that has been compared with other plasmids, while in strain ST27MN3, the naphthalene degradative genes were detected in the chromosome sequence. Phylogenomic analysis of the core gene sequences showed that strains 19SMN4T and ST27MN3 shared 3,995 genes and were closely related to members of the species “Stutzerimonas songnenensis” and Stutzerimonas perfectomarina, as well as to the Stutzerimonas phylogenomic species, pgs9, pgs16 and pgs24. The aggregate average nucleotide identity (ANI) indicated that strains 19SMN4T and ST27MN3 belonged to the same genomic species, whereas the genomic indices with their closest-related type strains were below the accepted species threshold (95 %). We therefore conclude that strains 19SMN4T and ST27MN3 represent a novel species of Stutzerimonas, for which the name Stutzerimonas decontaminans is proposed; the type strain is 19SMN4T (=CCUG44593T = DSM6084T = LMG18521T).  相似文献   

10.
The genus Pseudo-nitzschia has attracted attention because of production of the toxin, domoic acid (DA), causing Amnesic Shellfish Poisoning (ASP). Pseudo-nitzschia blooms occur frequently in Chinese coastal waters, and DA has been detected in several marine organisms, but so far no Pseudo-nitzschia strains from Chinese waters have been shown to produce DA. In this study, monoclonal Pseudo-nitzschia strains were established from Chinese coastal waters and examined using light microscopy, electron microscopy and molecular markers. Five strains, sharing distinct morphological and molecular features differentiating them from other Pseudo-nitzschia species, represent a new species, Pseudo-nitzschia simulans sp. nov. Morphologically, the taxon belongs to the P. pseudodelicatissima group, cells possessing a central nodule and each stria comprising one row of poroids. The new species is characterized by the poroid structure, which typically comprises two sectors, each sector located near opposite margins of the poroid. The production of DA was examined by liquid chromatography tandem mass spectrometry (LC–MS/MS) analyses of cells in stationary growth phase. Domoic acid was detected in one of the five strains, with concentrations around 1.05–1.54 fg cell−1. This is the first toxigenic diatom species reported from Chinese waters.  相似文献   

11.
Three plant rhizogenic strains O132T, O115 and O34 isolated from Cucumis sp. L. were assessed for taxonomic affiliation by using polyphasic taxonomic methods. Based on the results of the sequence analysis of the 16S rRNA and multilocus sequence analysis (MLSA) of the three housekeeping genes atpD, recA and rpoB, all the strains were clustered within the genus Agrobacterium where they form a novel branch. Their closest relative was Agrobacterium tomkonis (genomospecies G3). Moreover, digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) comparisons between strains O132T and O34 and their closest relatives provided evidence that they constitute a new species, because the obtained values were significantly below the threshold considered as a borderline for the species delineation. Whole-genome phylogenomic analysis also indicated that the cucumber strains are located within the separate, well-delineated biovar 1 sub-clade of the genus Agrobacterium. Furthermore, the physiological and biochemical properties of these strains allowed to distinguish them from their closest related species of the genus Agrobacterium. As a result of the performed overall characterization, we propose a new species as Agrobacterium cucumeris sp. nov., with O132T (=CFBP 8997T = LMG 32451T) as the type strain.  相似文献   

12.
A new species of toxic benthic dinoflagellate is described based on laboratory cultures isolated from two locations from Brazil, Rio de Janeiro and Bahia. The morphology was studied with SEM and LM. Cells are elliptical in right thecal view and flat. They are 37–44 μm long and 29–36 μm wide. The right thecal plate has a V shaped indentation where six platelets can be identified. The thecal surface of both thecal plates is smooth and has round or kidney shaped and uniformly distributed pores except in the central area of the cell, and a line of marginal pores. Some cells present an elongated depression on the central area of the apical part of the right thecal plate. Prorocentrum caipirignum is similar to Prorocentrum lima in its morphology, but can be differentiated by the general cell shape, being elliptical while P. lima is ovoid. In the phylogenetic trees based on ITS and LSU rDNA sequences, the P. caipirignum clade appears close to the clades of P. lima and Prorocentrum hoffmannianum. The Brazilian strains of P. caipirignum formed a clade with strains from Cuba, Hainan Island and Malaysia and it is therefore likely that this new species has a broad tropical distribution. Prorocentrum caipirignum is a toxic species that produces okadaic acid and the fast acting toxin prorocentrolide.  相似文献   

13.
Five novel ascosporogenous yeast strains (H382, H396, H409, H433T and H441) were found through a survey of vacuum-packed beef microbiota. Sequence analysis of ITS domain and LSU rRNA genes showed that the new strains represent a distinct lineage within the genus Kazachstania, closely related to Kazachstania lodderae (97.0 % identity) and Kazachstania ichnusensis (96.1 % identity). The main difference of strains H382, H396, H409, H433T and H441 to strains of known Kazachstania species is the maximum growth temperature, which is below 20 °C for the new strains, whereas related species grow at 25 °C. Furthermore, the strains differed from known Kazachstania species in assimilation and fermentation patterns of carbon sources. Based on these characteristics, the five strains are considered to represent a novel species of the genus Kazachstania for which the name Kazachstania psychrophila sp. nov. is proposed. The type strain is H433T (DSM 26230T=CBS 12689T). The Mycobank number of the type strain is MB 803980.  相似文献   

14.
15.
Social bees harbor a community of gut mutualistic bacteria, among which bifidobacteria occupy an important niche. Recently, four novel species have been isolated from guts of different bumblebees, thus allowing to suppose that a core bifidobacterial population may be present in wild solitary bees. To date there is sparse information about bifidobacteria in solitary bees such as Xylocopa and Osmia spp., this study is therefore focused on the isolation and characterization of bifidobacterial strains from solitary bees, in particular carpenter bee (Xylocopa violacea), builder bee (Osmia cornuta), and red mason bee (Osmia rufa). Among the isolates from Osmia spp. no new species have been detected whereas among Xylocopa isolates four strains (XV2, XV4, XV10, XV16) belonging to putative new species were found. Isolated strains are Gram-positive, lactate- and acetate-producing and possess the fructose-6-phosphate phosphoketolase enzyme. Full genome sequencing and genome annotation were performed for XV2 and XV10. Phylogenetic relationships were determined using partial and complete 16S rRNA sequences and hsp60 restriction analysis that confirmed the belonging of the new strains to Bifidobacterium genus and the relatedness of the strains XV2 and XV10 with XV16 and XV4, respectively. Phenotypic tests were performed for the proposed type strains, reference strains and their closest neighbor in the phylogenetic tree. The results support the proposal of two novel species Bifidobacterium xylocopae sp. nov. whose type strain is XV2 (=DSM 104955T = LMG 30142T), reference strain XV16 and Bifidobacterium aemilianum sp. nov. whose type strain is XV10 (=DSM 104956T = LMG 30143T), reference strain XV4.  相似文献   

16.
The molecular taxonomic analysis of yeasts isolated from Verbascum flowers collected in central Georgia identified strains that could be assigned to the species Cryptococcus adeliensis, Cryptococcus magnus and Moniliella megachiliensis detected previously also in substrates associated with insects and other animals and a hitherto undescribed species for which the name Candida verbasci is proposed. The new species forms slightly pink colonies, propagates by mostly unipolar budding, forms invasive pseudomycelium, and the sequences of its D1/D2 LSU rRNA genes and ITS1-5.8S-ITS2 regions indicate close phylogenetic relationship with a group of species that form a cluster basal to the Candida albicans/Lodderomyces elongisporus clade. The type strain is 11-1055T. It has been deposited in Centralbureau voor Schimmelcultures (Utrecht, the Netherlands) as CBS 12699T, the National Collection of Agricultural and Industrial Microorganisms (Budapest, Hungary) as NCAIM Y.02048T and the Culture Collection of Yeasts (Bratislava, Slovakia) as CCY 29-185-1T. The GenBank accession numbers for nucleotide sequences of the C. verbasci type strain are: JX515981 (D1/D2 domain of the 26S rRNA gene) and JX515982 (ITS1-5.8S-ITS2). Mycobank: MB 801391.  相似文献   

17.
18.
In the framework of a large-scale rock sampling in Continental Antarctica, a number of yeasts have been isolated. Two strains that are unable to grow above 20 °C and that have low ITS sequence similarities with available data in the public domain were found. The D1/D2 LSU molecular phylogeny placed them in an isolated position in the genus Taphrina, supporting their affiliation to a not yet described species. Because the new species is able to grow in its anamorphic state only, the species Taphrina antarctica f.a. (forma asexualis) sp. nov. has been proposed to accommodate both strains (type strain DBVPG 5268T, DSM 27485T and CBS 13532T). Lalaria and Taphrina species are dimorphic ascomycetes, where the anamorphic yeast represents the saprotrophic state and the teleomorph is the parasitic counterpart on plants. This is the first record for this genus in Antarctica; since plants are absent on the continent, we hypothesize that the fungus may have focused on the saprotrophic part of its life cycle to overcome the absence of its natural host and adapt environmental constrains. Following the new International Code of Nomenclature for Algae, Fungi and Plants (Melbourne Code 2011) the reorganization of TaphrinaLalaria species in the teleomorphic genus Taphrina is proposed. We emend the diagnosis of the genus Taphrina to accommodate asexual saprobic states of these fungi. Taphrina antarctica was registered in MycoBank under MB 808028.  相似文献   

19.
Nineteen bacteria isolates recovered from shellfish samples (mussels and oysters) showed a new and specific 16S rDNA-RFLP pattern with an Arcobacter identification method designed to recognize all species described up to 2008. These results suggested that they could belong to a new species. ERIC-PCR revealed that the 19 isolates belonged to 3 different strains. The sequence of the 16S rRNA gene of a representative strain (F98-3T) showed 97.6% similarity with the closest species Arcobacter marinus followed by Arcobacter halophilus (95.6%) and Arcobacter mytili (94.7%). The phylogenetic analysis with the16S rRNA, rpoB, gyrB and hsp60 genes placed the shellfish strains within the same cluster as the three species mentioned (also isolated from saline habitats) but they formed an independent phylogenetic line. The DDH results between strain F98-3T and A. marinus (54.8% ± 1.05), confirmed that it represents a new species. Several biochemical tests differentiated the shellfish isolates from all other Arcobacter species. Although the new species was different from A. mytili, they shared not only the same habitat (mussels) but also the characteristic of being so far the only Arcobacter species that are simultaneously negative for urea and indoxyl acetate hydrolysis. All results supported the classification of the shellfish strains as a new species, for which the name Arcobacter molluscorum sp. nov. with the type strain F98-3T is proposed (=CECT 7696T = LMG 25693T).  相似文献   

20.
Planctomycetes are bacteria with particular characteristics such as internal membrane systems encompassing intracellular compartments, proteinaceous cell walls, cell division by yeast-like budding and large genomes. These bacteria inhabit a wide range of habitats, including marine ecosystems, in which ultra-violet radiation has a potential harmful impact in living organisms. To evaluate the effect of ultra-violet C on the genome of several marine strains of Planctomycetes, we developed an easy and fast DNA diffusion assay in which the cell wall was degraded with papain, the wall-free cells were embedded in an agarose microgel and lysed. The presence of double strand breaks and unwinding by single strand breaks allow DNA diffusion, which is visible as a halo upon DNA staining. The number of cells presenting DNA diffusion correlated with the dose of ultra-violet C or hydrogen peroxide. From DNA damage and viability experiments, we found evidence indicating that some strains of Planctomycetes are significantly resistant to ultra-violet C radiation, showing lower sensitivity than the known resistant Arthrobacter sp. The more resistant strains were those phylogenetically closer to Rhodopirellula baltica, suggesting that these species are adapted to habitats under the influence of ultra-violet radiation. Our results provide evidence indicating that the mechanism of resistance involves DNA damage repair and/or other DNA ultra-violet C-protective mechanism.  相似文献   

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