蝰科(Viperidae)蝮亚科(Crotalinae)线粒体12S rRNA基因序列分析及其系统发育

对蝮亚科(蛇岛蝮Gloydius shedaoensis Zhao、黑眉蝮Gloydius saxatilis Emelianov、乌苏里蝮Gloydius ussurriensis Emelianov、竹叶青Trimeresurus stejnegeri Schmidt和分别来自不同地区的尖吻蝮Deinagkistrodon acutus Guenther、短尾蝮Gloydius brevicaudus Stejneger各两条)6种蛇共8个个体测定、分析了约370bp线粒体12S rRNA基因序列,以游蛇科链蛇属半棱鳞链蛇Dinodon semicarinatus序列为外群构建分子系统树。

黄牛、水牛体内人肉孢子虫18S rRNA基因研究及虫种鉴定

对自然感染的水牛源的人肉孢子虫以及黄牛源人肉孢子虫DNA的18S rRNA基因的PCR扩增产物进行了测序。对所获的863 bp的18S rRNA基因分析比较表明，二者有较高的同源性，因此认为二者可能同是一种肉孢子虫——人肉孢子虫（Sarcocystis hominis Railliet and Lucet，1891）。由此推断，不仅黄牛可作为人肉孢子虫的中间宿主，水牛也可作为人肉孢子虫的中间宿主。

Identification of Sarcocystis hominis-like (Protozoa : Sarcocystidae) cyst in water buffalo (Bubalus bubalis) based on 18S rRNA gene sequences

DNA templates were extracted from isolates of Sarcocystis hominis-like cysts collected from cattle and water buffalo, as well as from Sarcocystis fusiformis cysts and Sarcocystis suihominis cysts. The 18S rRNA genes were amplified using DNA from a single

Characterization of Sarcocystis species in domestic animals using a PCR-RFLP analysis of variation in the 18S rRNA gene: a cost-effective and simple technique for routine species identification

Thirteen restriction endonucleases were used to investigate nucleotide sequence variation in the 18S rRNA DNA of 88 individuals from ten Sarcocystis taxa collected as cysts from their intermediate hosts, swine, cattle and water buffalo. A DNA sequence of

Analysis of 18S rRNA gene of Octostigma sinensis (Projapygoidea : Octostigmatidae) supports the monophyly of Diplura

The phylogenetic position of Diplura within Hexapoda has been controversial. There are three major lineages in Diplura: Campodeoidea, Projapygoidea, and Japygoidea. However, most of the previous studies were restricted to Campodeoidea and Japygoidea. Unti

Phylogenetic relationships of the Chinese brown frogs (Genus rana) inferred from partial mitochondrial 12S and 16S rRNA gene sequences

Based on partial sequences of the 12S and 16S ribosomal RNA genes, we estimated phylogenetic relationships among brown frogs of the Rana temporaria group from China. From the phylogenetic trees obtained, we propose to include Rana zhengi in the brown frog

Molecular dynamics simulation on the complex of the tobramycin and 16S rRNA a site

A 3. 6 ns molecular dynamics simulation was carried out on the complex system of tobramycin and 16S rRNA in order to understand the speciality recognition mechanism between tobramycin and 16S rRNA at the molecular level. The results demonstrate that two l

Non-monophyly of Rhacophorus rhodopus,Theloderma and Philautus albopunctatus Inferred from Mitochondrial 16S rRNA Gene Sequences

测定了4个种(红蹼树蛙、黑蹼树蛙、白斑小树蛙和红吸盘小树蛙)共11个种群的16S rRNA基因片段.双斑树蛙、马来棱皮树蛙、越南棱皮树蛙以及日本溪树蛙的同源序列通过GenBank检索获得.去除所有插入、缺失及模糊位点后,比对序列长度为500 bp,其中变异位点115个,简约信息位点92个.以日本溪树蛙为外群,运用Bayesian法、MP法和ML法构建了系统发育树.结果表明红蹼树蛙和白斑小树蛙在种级水平上均不是单系.红蹼树蛙海南种群与双斑树蛙亲缘关系更近,并且来自云南不同地理种群的红蹼树蛙可以分为两大支系;越南棱皮树蛙与红吸盘小树蛙聚为一支,马来棱皮树蛙嵌套在白斑小树蛙不同地理种群中.进而认为白斑小树蛙是马来棱皮树蛙的同物异名,建议将红吸盘小树蛙并入棱皮树蛙属.

Generic allocation of Indian and Sri Lankan Philautus (Anura: Rhacophoridae) inferred from 12S and 16S rRNA genes

The generic allocation of Indian and Sri Lankan Philautus needs further examination. In this study, a comprehensive understanding of the phylogeny of Indian and Sri Lankan Philautus is obtained based on 125 and 16S rRNA genes. All phylogenetic analyses indicate that Indian-Sri Lankan Philautus, Philautus menglaensis, Philautus longchuanensis, and Philautus gryllus form a well supported clade, separate from Philautus of Sunda Islands that form another well supported clade representing true Philautus. This result supports the designation of the genus Pseudophilautus to accommodate the Indian and Sri Lankan species. Pseudophilautus consists of two major lineages, one comprises the majority of Indian species, Chinese species, and Southeast Asian species, and one comprises all Sri Lankan species and a few Indian species. Pseudophilautus may have originated in South Asia and dispersed into Southeast Asia and China. Based on the results, we further suggest that Philautus cf. gryllus (MNHN1997.5460) belongs to the genus Kurixalus. (C) 2010 Published by Elsevier Ltd.

Tobramycin与16S rRNA A位点复合物的分子动力学模拟

采用分子动力学方法(Molecular dynamics,MD)对托普霉素(Tobramycin)与16S rRNA的A位点复合物的特异性识别机制进行了理论模拟研究,模拟时间为3.6 ns. 结果表明,A位点中波动最大的部位是两个环外碱基A1492和A1493;tobramycin的环Ⅰ和环Ⅱ是其最保守的结构单元,可能参与了Tobramycin与16S rRNA的A位点之间的特异性识别. 另外,发现一个残存时间为3.6 ns的"结构化"水分子,它桥接了Tobramycin环Ⅱ的N3与环Ⅰ的N6′之间的氢键,稳定了Tobramycin的结构;Tobramycin周围水合密度较高的位点出现在环Ⅰ和环Ⅱ附近,这也正是晶体结构中形成较多水媒介氢键及动力学模拟中结构化水分子出现的位置. 动力学模拟证实Tobramycin与16S rRNA间的结合是大量氢键及水分子相互作用的结果,这有助于设计和开发以Tobramycin为基础,具有高亲和力及特异性的16S rRNA抑制剂.

rRNA ———行使核糖体功能的主体

高分辨率的核糖体精细结构揭示,核糖体行使功能的主体是RNA。核糖体的主要功能:催化肽键形成,识别、 选择tRNA 等都主要由rRNA 来完成。

Phylogenetic analysis of the family Thermaceae with an emphasis on signature position and secondary structure of 16S rRNA

The sequences of the 16S rRNA genes from 38 strains of the family Thermaceae were compared by alignment analysis. The genus-specific and species-specific base substitutions or base deletions (signature positions) were found in three hypervariable regions (in the helices 6, 10 and 17). The differentiation of secondary structures of the high variable regions in the 5' end (38-497) containing several signature positions further supported the concept. Based on the comparisons of the secondary structures in the segments of 16S rRNAs, a key to the species of the family Thermaceae was proposed. (C) 2003 Published by Elsevier Science B.V. on behalf of the Federation of European Microbiological Societies.