扁刺蛾核型多角体病毒的形态结构与某些生化特性的测定

扁刺蛾核型多角体病毒是一种单粒包埋型的杆状病毒,在扫描电镜下呈不规则多面体。病毒多角体大小不一致,平均直径为0.59μ。病毒粒子为340×85nm. 经SDS—PAGE分析,病毒的多角体蛋白主带分子量为29500道尔顿;病毒粒子的结构蛋白具有25条多肽,分子量为17.8～69.5×10~4道尔顿。病毒多角体蛋白氨基酸组成中富含Asp和Glu,而His、Cys、Met的含量却很低。病毒DNA的分子量为67.89×10~6道尔顿。     

棉铃虫质型多角体病毒的某些生物物理和生物化学特性

本文对棉铃虫质型多角体病毒中国江苏分离株的生物物理和生物化学特性进行了研究,棉铃虫CPV通过其寄主幼虫大量增殖,经蔗糖梯度超离心纯化,CPV粒子由碱液溶解多角体释出,其沉降系数为403.9S,分子量为41.9×10~6,CPV多角体蛋白的主要组份为一种,分子量为27,000;CPV粒子结构蛋白则由六种多肽组成,经聚丙烯酰胺凝胶等电聚焦电泳,CPV多角体蛋白和CPV粒子均包含10种以上的多肽组份,经双向电泳,(PV粒子结构蛋白包含15种以上的多肽组份,CPV多角体蛋白氨基酸组成中不含半胱氨酸,其碱性氨基酸与酸性氨基酸比值为1.005,用SDS-热酚法提取所得CPV核酸,其解链温度为83侧;其碱基组成,A=U,G=C,说明CPV核酸是双链RNA,其G+C％为43％,在1％琼脂糖凝胶和3％聚丙烯酰胺凝胶中电泳,CPV RNA分别可分得11和13条基因片段,各片段大小为0.51～2.45×10~6,总分子量为17.94×10~6,电镜研究显示了CPV RNA在0.3μ,0.6μ1.0μ处有3个分布峰。     

黄褐天幕毛虫核型多角体病毒的形态结构与某些生化特性的研究

黄褐天幕毛虫核型多角体病毒是一种多粒包埋型病毒。在扫描电镜下观察,多角体呈不规则多面体,大小不一致,平均直径为1.30μm。病毒粒子为杆状,大小为366×90nm。病毒核酸为一环状DNA,长度约为37.2μm。经限制性内切酶酶解分析,DNA总分子量为77.1×10~6D。病毒多角体蛋白宫含ASP和Glu,而His、Cys、Met含量较少。经SDS-PAGE分析,多角体蛋白主带的分子量为30.2KD;病毒粒子含21条多肽,分子量范围在16.5—107KD之间。     

灰茶尺蛾核型多角体病毒的精细结构及生物学特性研究

在湖北省茶园害虫灰茶尺蛾(Ectropis grisescens W.)幼虫体内分离到一株核型多角体病毒,属杆状病毒科单粒包埋型。多角体呈不规则的多面体,平均大小为1.76μm。病毒粒子平均大小为287×65nm,粒子两端有环状的帽状结构。测量EgNPV-DNA的分子量约为34×10⁶道尔顿。生物毒力测定其LD₅₆为8.6×10⁵PIB/ml。     

两株蓖麻蚕核型多角体病毒的比较研究

本文描述来源不同的两株菌麻蚕多角体病毒的形态特征和理化特性。一株为较长期饲喂马桑叶的蓖麻蚕从自然罹死的幼虫和蛹中分离的多角体病毒（简称ArscsNPV);另一株为饲喂蓖麻叶的蓖麻蚕从幼虫分离的核型多角体病毒（简称ArscsNPV);另一株为饲喂蓖麻叶的蓖麻蚕从幼虫分离的核型多角体病毒（简称ArNPV)。两株核型多角体病ArNPV多角体大小约1．2－2．0μm最大的可达2．9μm。两株NPV病毒粒子均为杆状,ArscsNPV病毒粒子大小平均为310×50nm;ArNPV病毒粒子大小为350×50nm。两株NPV均为多粒包埋型。两株NPV的多角体蛋白均为单一组分,ArscsNPV多角体蛋白分子量为27．5kd;ArNPV多角体蛋白分子量为28kd。两株NPV的病毒粒子结构多肽均含有21条多肽,其中各多肽分子量有所差异。ArscsNPV的病毒粒子多肽分子量范围为11－130kd;ArNPV病毒粒子多肽分子量范围为11－96kd,其中有11种多肽了量彼此相同包括两种主要多肽（54kd和33kd）。用SDS－苯酚提取的病毒核酸,经实验证明均为双链DNA型使用几种内切酶酶解,求得两株NPV的核酸分子量,ArscsNPV为52．4×10^6d;ArNPV为73．5×10^6d。     

油桐尺蠖核型多角体病毒结构多肽的分析

本文采用不连续系统的垂直板SDS—PAGE对油桐尺蠖核型多角体病毒(Buzura suppressaria Guenee Nuclear Polyhedrosis Virus简称BsNPV)的多角体蛋白、病毒粒子的结构多肽进行了分析。结果表明,经EDTA和热处理的多角体蛋白仅有一条主带,其分子量为31×10~3±1000d;病毒粒子至少有23种结构多肽,其分子量的范围在13—107×10~3d之间。用PAS染色测定多角体蛋白、病毒粒子中的糖蛋白,结果呈阴性反应。     

烟青虫质型多角体病毒的形态及某些理化特性

本文对烟青虫(Heliothis assulta)质型多角体病毒(CPV)的形态大小以及某些理化特性进行了研究。烟青虫CPV多角体为正五角形的十二面体,大小为0.8-4.6μm;CPV 粒子为外形呈六角形或球形的廿面体,大小为62nm。CPV多角体蛋白的主要多肽为一种,分子量23000,为非糖蛋白。 用SDS-酚法提取的CPV基因,经Rnase I和Dnase I处理后在1%琼脂糖凝胶上电泳,结果表明 其基因是双链RNA,并由10个基因片段组成。各片段大小为0.3-2.68X10⁶,总分子量为15.85x10⁶。本文所报道的烟青虫质型多角体病毒在国内外尚属首次。     

薄荷伪造桥虫NPV感染斜纹夜蛾幼虫分离的一种新NPV特性的研究

用薄荷伪造桥虫核型多角体病毒(Argroyamma agnata NPV)(以下简称Aa NPV)在室内感染斜纹夜蛾(Prodenia litura)幼虫,从死虫体内分离到一种NPV。经电镜观察,多角体蛋白分析、病毒核酸的限制性内切酶酶解分析等研究,证明此多角体直径为1.5—2.6/μm,病毒粒子为杆状,其大小为100—150×420nm,病毒粒子为多粒包埋型。提纯的多角体蛋白只有一种多肽,分子量为33,500d,提纯的病毒粒子的结构多肽至少有15种,其分子量范围为15,600     

薄荷伪造桥虫多角体病毒及其核酸的限制性内切酶酶解分析

本文描述了从薄荷伪造桥虫(Argrogramma agnata stgr.)幼虫分离到的一种核型多角体病毒的形态以及采用简便的方法提取的核酸,经限制性内切酶 EcoRI,BamHI,HindⅢ,BglⅠ,BglⅡ和BglⅠ+BglⅡ,BamHl+EcoRl 酶解,获得该病毒核酸的酶解带谱。以入 DNA 的 EcoRl 酶解片段在凝胶中的迁移率与相应 DNA 片段分子量的对数值作标准曲线。从曲线上求得薄荷伪造桥虫多角体病毒核酸酶解各片段的分子量.此病毒核酸的平均分子量为108.51×10~6道尔顿。     

木毒蛾质型多角体病毒形态结构及理化特性的研究

木毒蛾质型多角体病毒呈不规则多面体,大小差异较大,大多数在０．８－２．１μｍ之间;病毒粒子在多角体内随机分布,病毒粒子为正二十面体结构,有１２个顶体,每个顶上均有一个球状结构,平均直径约为６０ｎｍ。经ＳＤＳ－ＰＡＧＥ分析,多角体蛋白由一条分子量为３１ｋＤ之间。多角体蛋白富含天冬氨酸,谷氨酸及酪氨酸,而半胱氨酸和甲硫氨酸含量较少,其碱性氨基酸与酸性氨基酸之比为１．４３。病毒核酸对ＲＮａｓｅ和ＤＮａｓ     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

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     

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.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.