汉坦病毒东方田鼠分离株ZT10的M基因序列的特性分析

分析东方田鼠分离汉坦病毒ZT10株M基因分子特征.提取汉坦病毒ZT10株感染细胞的总RNA,应用逆转录聚合酶链反应(RT-PCR)扩增ZT10株M片段全基因,克隆于T载体并测序,对其进行序列分析.结果显示汉坦病毒ZT10株的基因组M片段长度为3651个核苷酸,编码1133个氨基酸.序列分析表明其为Seoul型汉坦病毒.与八株Seoul型汉坦病毒的M片段同源性为84.0%～96.3%,而与HTN型汉坦病毒的同源性则较低,与从田鼠分离的汉坦病毒(Prospect Hill virus, Tula virus, Khabarovsk virus, Isla vista virus)核苷酸同源性仅为57.5%～60.9%,且与浙江省Seoul型分离株Guo3同源性较低,表明浙江省可能存在着另一Seoul亚型的汉坦病毒.     

我国汉坦病毒基因型和基因亚型的分布研究

为了搞清全国汉坦病毒的基因型和亚型的分布情况,广泛收集了全国各地汉坦病毒毒株、阳性病人血清和阳性鼠肺,并应用RT-PCR的方法,应用汉坦病毒型特异性引物,对这些不同来源的阳性标本中汉坦病毒型特异性M和S片段进行扩增和测序,并与其它已知病毒序列进行比较,以明确其型别和亚型及其在全国的分布情况.结果表明:我国HFRS各疫区仍然为HTNV和SEOV两型病毒,但亚型分布差异较大,其中HTNV可分为9个亚型,SEOV则有4～6个亚型.Q32株的部分M和S片段分属于H9和H2亚型,是一个基因重排病毒,而Nc167株在系统发生上与其它HTNV明显不同,比较核苷酸序列发现,其M片段与其它HTNV的同源性在71.3%～76.7%之间,S片段与其它HTNV的同源性只有52.3%～57.8%,可能是一个新型病毒.     

汉滩病毒西安分离株84FLi的L片段核苷酸序列测定以及分析

采用逆转录-聚合酶链式反应(RT-PCR),分节段扩增汉滩病毒 84FLi株的L基因片段cDNA,纯化的PCR产物片段直接用于序列测定或克隆入pND18-T载体中 进行测序.结果表明,84FLi株的L片段cDNA由6533个核苷酸组成,四种核苷酸的比例分别为A33.39%,C16.43%,G20. 74%,T29.44%.GC含量为37.17%,AT含量为62.83%.推导出的最大开放读码框架为从38到649 3 ,共编码2151个氨基酸.序列同源性分析表明,84FLi株核苷酸与HTN型国际标准毒株76-11 8的同源性为83.7%,差异性为18.8%;而与中国株A9的同源性高达97.6%,差异性仅为2.4%. 与SEO型代表Seoul80-39的同源性为75.2%,66.1%～66.5%.L片段的氨基酸比较分析表明, L 片段与HTN型间的同源性为97.5%～98.0%,而与SEO型的同源性为83.5%～85.5%.与PUC、TUL 、SN和AND等其它型汉滩病毒的同源性仅为68.6%～69.6%.结果表明84FLi株属于HTN型,并与分离自国内的HTN型病毒高度同源.     

汉坦病毒中国疫苗株Z37M片段的克隆及序列分析

汉坦病毒Z37株是从褐家鼠体内分离到的,用于生产双价肾综合征出血热疫苗的病毒毒株之一,血清分型为SEO型。利用RT-PCR方法扩增Z37株M基因片段cDNA,克隆入质粒载体,进行核苷酸序列测定及分析。Z37株M基因片段由3651个核苷酸组成,只有一个开放读码框架,共编码1133个氨基酸。与HTN型病毒(76-118、A9、HV-114)的核苷酸和氨基酸同源性分别为71.8%～72.1%、76.2%～76.7%,与SEO型(R22、L99、80-39)的核苷酸和氨基酸同源性分别为95.3%～96.1%、95.3%～98.9%。这一结果的获得进一步从分子水平确定了Z37株的型别,并为研制M基因片段重组疫苗打下基础。     

汉滩病毒西安分离株84FLi的L片段核苷酸序列测定以及分析

采用逆转录 聚合酶链式反应 (RT PCR) ,分节段扩增汉滩病毒 84FLi株的L基因片段cDNA ,纯化的PCR产物片段直接用于序列测定或克隆入 pND18 T载体中进行测序。结果表明 ,84FLi株的L片段cDNA由 6 5 33个核苷酸组成 ,四种核苷酸的比例分别为A33.39% ,C16 .4 3% ,G2 0 .74 % ,T2 9.4 4 %。GC含量为 37.17% ,AT含量为6 2 .83%。推导出的最大开放读码框架为从 38到 6 4 93,共编码 2 15 1个氨基酸。序列同源性分析表明 ,84FLi株核苷酸与HTN型国际标准毒株 76 118的同源性为 83.7% ,差异性为 18.8% ;而与中国株A9的同源性高达 97.6 % ,差异性仅为 2 .4 %。与SEO型代表Seoul80 39的同源性为 75 .2 % ,6 6 .1%～ 6 6 .5 %。L片段的氨基酸比较分析表明 ,L片段与HTN型间的同源性为 97.5 %～ 98.0 % ,而与SEO型的同源性为 83.5 %～ 85 .5 %。与PUC、TUL、SN和AND等其它型汉滩病毒的同源性仅为 6 8.6 %～ 6 9.6 %。结果表明 84FLi株属于HTN型 ,并与分离自国内的HTN型病毒高度同源     

阿卡斑病毒云南分离株全基因组序列特征研究

为阐明分离自云南省的蚊媒阿卡斑病毒(Akabane virus,AKV)DHL10M110株(简称云南株)的分子生物学特征,采用RT-PCR和核苷酸序列测定方法,对云南株进行全基因组序列测定和分析。结果获得了云南株全基因组核苷酸序列,该病毒株的L、M和S基因核苷酸序列全长分别为6 869bp、4 309bp和856bp,其中开放读码框(Open reading frame,ORF)核苷酸序列依次为6 756bp、4 206bp和702bp,并分别编码2252、1402和234个氨基酸。这三个基因片段ORF的系统进化分析表明,云南株L基因与AKV标准株OBE-1(日本)和AKVS-7/SKR/2010株(韩国)处于同一进化分支;在M和S基因进化树中,云南株与日本、韩国和台湾地区的AKV流行株亲缘关系较近,但云南株单独处于一个小的进化分支。同源性分析表明,云南株L、M和S片段ORF与OBE-1株的核苷酸(氨基酸)同源性分别为92.6%(98%)、88.5%(94%)和96.4%(99.1%)。云南株与OBE-1株的L、M和S片段分别有45、84和2个氨基酸位点的差异。此外,无论L、M和S基因核苷酸序列的同源性或系统进化分析均表明,云南株与肯尼亚和澳大利亚AKV分离株进化关系较远,同源性较低。本研究进一步通过病毒全基因组序列分析证实DHL10M110病毒株为AKV,属亚洲进化群,但与日本和韩国株相比仍有一定差异,云南株地域特征明显。这是首次在中国大陆地区测定到该病毒的全基因组序列。     

汉坦病毒汉滩型特殊新亚型的发现

应用RT－PCR扩增了皖南山区分离株AH09的M和S片段全基因,克隆于T载体,纯化后测定序列。结果AH09株M片段的全基因序列共3625个核苷酸,编码1135个氨基酸;S片段的全基因序列共1724个核苷酸,编码430个氨基酸。M和S片段全基因核苷酸和氨基酸与汉坦病毒各型株的代表株和HTN型毒株的同源性比较表明,AH09株分枝与HTN型接近,与其它各型病毒则相距较远,故确定为HTN型毒株,但AH09株与HTN型毒株的M和S片段全基因序列有差异,其差异分别高达23．6％和20．4％,经种系发生分析,AH09株是迄今为止所发现的HTN型病毒中差异最大的新基因亚型病毒株,AH09株病毒M片段的氨基酸与HTN型相差13．5％至14．8％,而S片段仅相差7％－8．1％,说明AH09毒株的变异主要发生在M片段。而ORF和3‘端的NCR区核苷酸序列分析比较说明,病毒的变异更主要集中在该片段的3‘端的NCR区。     

汉坦病毒K24株M和S片段基因的结构特征

为研究汉坦病毒K24株M和S片段基因的结构特征,从病毒感染细胞提取细胞总RNA,经35个循环的一次性PCR得到了与理论值相符合产物,将RT-PCR产物直接克隆T载体,经K24毒株M片段的全基因序列共3 653个核苷酸,四种核苷酸的酶切和PCR鉴定正确的克隆通过柱纯化后进行序列测定,结果比例分别为A 30.44%,T30.14%,G20.72%,C 18.70%,GC含量为39.42%,AT含量为60.58%,编码1 133个氨基酸.S片段的全基因序列共1 772个核苷酸,四种核苷酸的比例分别为A31.30%,G26.05%,T22.79%,C19.77%,GC含量为45.81%,AT含量为54.19%,共编码429个氨基酸.K24株M片段核苷酸全基因和氨基酸与HTN型毒株同源率分别为70.7%～71.2%和75.9%～76.9%,与SEO型为95.2%～99.2%和95.9%～99.4%.S片段与HTN 76～118和SEO SR-11病毒的比较,核苷酸同源率分别为74.0%和95.6%,氨基酸同源率为83.3%和97.9%,与M片段的结果相类似.M片段氨基酸与SEO型10个毒株存在4个氨基酸替代.应用DNASTAR软件的系统发生分析方法分别绘出了基于M片段核苷酸及推导氨基酸的系统发生树.     

中国分离巴泰病毒基因组全编码区序列测定和分析

采用RT-PCR和TAIL-PCR方法,首次对我国分离的巴泰病毒(YN92-4株)基因组的全编码区进行序列测定和分析。结果显示,YN92-4株病毒基因组由S、M、L三个片段组成,长度分别为947、4 371、6 860个核苷酸。其中,S片段基因编码由234个氨基酸残基组成的核衣壳蛋白和由102个氨基酸残基组成的非结构蛋白,M片段基因编码由1 435个氨基酸残基组成的前体蛋白,L片段基因编码由2 239个氨基酸残基组成的RNA聚合酶。与国外其它地区的巴泰病毒分离株进行基因组全编码区序列比较后发现,YN92-4株与日本牛血清分离株(ON-7/B/01株)在S、M片段核苷酸(氨基酸)的同源性最高,分别为97.7%(100%)和95.7%(98%);由于本研究首次开展对巴泰病毒L基因片段核苷酸序列的研究,因此国际基因库尚无可参考的序列信息,本研究比较了我国分离的巴泰病毒与同一血清组的代表病毒Bunyamwera病毒L片段的核苷酸和氨基酸序列同源性,分别为73.5%和81.6%。系统进化分析显示,YN92-4株基因组与其它巴泰病毒分离株在各自分支下形成独立分支。本研究提示我国分离的巴泰病毒YN92-4株未发生基因重配(...     

陕西省9株乙脑病毒的分离及E基因序列分析

分析陕西省分离的9株乙脑病毒基因组序列特征。使用乙脑病毒全基因组序列测定引物进行RT-PCR扩增,扩增产物进行测序,拼接后获得基因组序列。利用MEGA 4.1、MegAlin、MEGA7.0等软件进行毒株的系统进化分析,并与P3株、减毒活疫苗SA14-14-2株及覆盖5个基因型别的其他乙脑病毒进行E基因序列比对。9株分离株3株分离自猪舍、6株分离自羊舍,其中4株获得全基因组序列,5株测得E基因序列。基于E基因序列进行毒株核苷酸、氨基酸同源性比较,结果显示分离株均与基因I型GI-b亚型毒株核苷酸和氨基酸同源性最高,核苷酸同源性范围为96.5%～99.7%、氨基酸同源性范围99.2%～100.0%;与SA14-14-2株核苷酸同源性范围为87.5%～88.9%、氨基酸同源性范围96.3%～97.2%;与P3株核苷酸同源性范围为87.6%～88.1%、氨基酸同源性范围96.7%～97.6%。分析09年（陕南地区）分离株与18年（关中地区）分离株的E基因核苷酸差异率为1.8%～2.9%、氨基酸差异率为0%～0.8%。陕西省自然界中循环的乙脑病毒以基因Ⅰ型为主,与P3株在抗原毒力关键位点无差异,...     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various     

Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in Pakistan

<正>Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However, there is limited genome information of IBDV