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1.
Rhodotorula aurantiaca (Saito) Lodder is an anamorphic basidiomycetous yeast species that belongs to the so-called "Erythrobasidium lineage" of the Urediniomycetes, according to molecular phylogenetic studies based on nucleotide sequence analyses of different ribosomal DNA regions. In the most recent editions of the yeast taxonomy treatises the species Rhodotorula colostri (Castelli) Lodder and Rhodotorula crocea Shifrine & Phaff were listed as synonyms of R. aurantiaca. Taxonomic heterogeneity within R. aurantiaca was demonstrated in a study based on whole-cell protein profiles and is also hinted at by the observed differences in physiological and biochemical characteristics among the different strains under that species name. We determined partial nucleotide sequences of the 26S rRNA gene (D1/D2 domains) of strains maintained in the CBS culture collection under R. aurantiaca, including the type strains of its synonyms. The results showed that R. colostri and R. crocea are clearly distinct from R. aurantiaca and from any other currently recognised basidiomycetous yeast species. Furthermore, phylogenetic analysis of the sequence data placed the former two species in separate lineages of the Microbotryomycetidae: R. colostri in the "ruineniae clade" (Sporidiobolus lineage or Sporidiobolales) and R. crocea loosely linked to Rhodotorula javanica (Microbotryum lineage).  相似文献   

2.
Two new species Mesothuria edwardensis sp.n. and Paradota marionensis sp.n., and four little-known species Cucumaria kerguelensis Théel, 1886, Cladodactyla crocea croceoides (Vaney, 1908), Psolidium incertum (Théel, 1886) and Synallactes challengeri (Théel, 1886) of holothurians are described from Marion and Prince Edward Islands.  相似文献   

3.
Genetic polymorphism of the two Palaearctic sulphur butterflies Colias crocea Fourc. and Colias erate Esp. was examined in serial samples using RAPD-PCR analysis of total cellular DNA. The primers OPA-01, OPA-03, OPA-04, OPA-08 were used. Taxon-specific molecular markers have been found for each species (markers OPA-08(250), OPA-08(380) were associated with rounded valve margin; marker OPA-04(400) was associated with angled valve margin). The genetic diversity of C. erate is considerably less than that of C. crocea. Genetic evidence for interspecific hybridization between C. crocea and C. erate is presented. Interspecific hybrids in question (paratypical forms such as f. chlorodona and f. pseudochrysodona) are situated at intermediate position with regard to the parental species on dendrograms (UPGMA) and maximal spanning trees (MST). Completely additional RAPD-spectra were not obtained though taxonomic status of these paratypical forms stay still vague. Only f. eratoides has DNA markers that are absent in spectra of other specimens tested. Probably it is a cryptic species unrevealed by common morphological and biochemical methods and its investigation by the methods of molecular genetics (sequence of cloned DNA) is very desirable.  相似文献   

4.
Marine Biotechnology - Large yellow croaker (Larimichthys crocea) is an important aquaculture species in China. This study analysed whole-genome methylation differences in liver tissues of young...  相似文献   

5.
During phylogenetic analyses of hymenomycetous yeasts based on 18S rDNA sequences, we found that Bullera armeniaca showed an extremely close phylogenetic relationship to Cryptococcus hungaricus. The analyses of internal transcribed spacer (ITS) regions of the two yeasts and the phylogenetically related species, Bullera aurantiaca and Bullera crocea, showed that B. armeniaca and C. hungaricus had identical sequences, indicating that these were conspecific. B. aurantiaca and B. crocea also showed high sequence similarity, 97.1% for ITS1, 100% for ITS2, and 98.7% for overall ITS regions. A DNA-DNA reassociation experiment revealed that B. armeniaca and C. hungaricus were conspecific and B. aurantiaca and B. crocea were two distinct species. These species occurred at a phylogenetically different lineage from that of Bulleromyces albus (anamorph: Bullera alba, type species of Bullera) and Filobasidiella neoformans (anamorph: Cryptococcus neoformans, neotype species of Cryptococcus). Based on these results, we emend the genus Dioszegia to include both ballistoconidium-forming and non-ballistoconidium-forming yeasts and redescribe the species Dioszegia hungarica. B. aurantiaca and B. crocea are also transferred to Dioszegia as Dioszegia aurantiaca comb. nov. and Dioszegia crocea comb. nov.  相似文献   

6.
A survey of epiphytic yeasts on leaves of selected Mediterranean plant species collected at the 'Arrábida Natural Park' (Portugal) yielded about 850 isolates, mostly of basidiomycetous affinity. Amongst the basidiomycetes, 35 strains showed the following characteristics: production of orange-coloured colonies, ability to produce starch-like compounds, assimilation of D-glucuronic acid and/or inositol, inability to utilize nitrate, and formation of ballistoconidia by many of the isolates. This group of yeasts was assigned to the Tremellales lineage of the Hymenomycetes and was further characterised using a combination of conventional phenotypic identification tests with molecular methods, namely PCR fingerprinting and rDNA sequencing. Eight additional strains presumptively identified as Bullera armeniaca, B. crocea or Cryptococcus hungaricus were also studied. Twenty-eight strains could be assigned to or were phylogenetically related to recognised species of Dioszegia in the 'Luteolus clade', but the 15 remaining strains belonged to other clades within the Tremellales. Ten phylloplane isolates were identified as Dioszegia hungarica, one as D. aurantiaca, another as D. crocea and three others were ascribed to the recently described species D. zsoltii. Seven novel species, viz. Cryptococcus amylolyticus, C. armeniacus, C. cistialbidi, Dioszegia buhagiarii, D. catarinonii, D. fristingensis and D. takashimae, are proposed for the remaining strains that did not correspond to any of the hitherto recognised species.  相似文献   

7.
本文从大黄鱼 (Pseucdosiaenacrocea)脑下垂体中提取得到总RNA ,根据近源鱼种生长激素(GH)基因保守序列设计了上游和下游引物 ,通过反转录和PCR扩增得到大黄鱼生长激素cDNA片断 ,并进行序列分析。所得到的序列与近源鱼种生长激素基因序列有较高的同源性 ,断定为大黄鱼生长激素基因序列 ,本序列的测定对进一步研究其生物活性和在工程菌中的表达及应用打下了基础。  相似文献   

8.
Acrorhynchides styliferus sp.n. from Norway and the British Isles and Polycystis contorta sp.n. and Typhlopolycystis coomansi sp.n. from Norway and the Mediterranean are described. Additional notes are given on the anatomy and distribution of Paracrorhynchus bergensis Karling, Polycystis groenlandica (Levinsen), P. crocea (Fabricius) and Typhlopolycystis mediterranea Brunet. The taxonomy of the species and the corresponding genera is discussed.  相似文献   

9.
The surface of many marine organisms is colonized by complex communities of microbes, yet our understanding of the diversity and role of host-associated microbes is still limited. We investigated the association between Ectopleura crocea (a colonial hydroid distributed worldwide in temperate waters) and prokaryotic assemblages colonizing the hydranth surface. We used, for the first time on a marine hydroid, a combination of electron and epifluorescence microscopy and 16S rDNA tag pyrosequencing to investigate the associated prokaryotic diversity. Dense assemblages of prokaryotes were associated with the hydrant surface. Two microbial morphotypes were observed: one horseshoe-shaped and one fusiform, worm-like. These prokaryotes were observed on the hydrozoan epidermis, but not in the portions covered by the perisarcal exoskeleton, and their abundance was higher in March while decreased in late spring. Molecular analyses showed that assemblages were dominated by Bacteria rather than Archaea. Bacterial assemblages were highly diversified, with up to 113 genera and 570 Operational Taxonomic Units (OTUs), many of which were rare and contributed to <0.4%. The two most abundant OTUs, likely corresponding to the two morphotypes present on the epidermis, were distantly related to Comamonadaceae (genus Delftia) and to Flavobacteriaceae (genus Polaribacter). Epibiontic bacteria were found on E. crocea from different geographic areas but not in other hydroid species in the same areas, suggesting that the host-microbe association is species-specific. This is the first detailed report of bacteria living on the hydrozoan epidermis, and indeed the first study reporting bacteria associated with the epithelium of E. crocea. Our results provide a starting point for future studies aiming at clarifying the role of this peculiar hydrozoan-bacterial association.  相似文献   

10.
利用多对引物,扩增并测定出大黄鱼16SrRNA基因和18SrRNA基因的部分序列,其长度分别为1202bp和1275bp,16SrRNA基因序列的GC含量为46.12%,18SrRNA基因的Gc含量为53.oo%。将大黄鱼16SrRNA基因序列与GenBank中15种硬骨鱼类的同源序列结合,同时将其18SrRNA基因序列与GenBank中9种脊索动物的同源序列相结合,运用软件获得各自序列间差异百分比,转换和颠换数值等信息。基于这两种基因序列,利用NJ法和BI法,分别构建16种硬骨鱼类和10种脊索动物的分子系统树。18SrRNA构建的系统树包括三大支,一支为哺乳类、鸟类和爬行类共6个物种,一支为两栖类的1个物种,另一支为2种硬骨鱼类。16SrRNA构建的系统树显示大黄鱼所在的石首鱼科与鲈科和盖刺鱼科亲缘关系较近。此外还讨论了这两个基因的序列特征。  相似文献   

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