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1.
抗草鱼出血病病毒多肽的结构分析   总被引:3,自引:0,他引:3  
王冰  田波 《Virologica Sinica》1998,13(4):358-363
将草鱼出血病病毒(GCHV873)颗粒与随机噬菌体九肽库在体外作用,三轮筛选后,从300个转化的单菌落中获得16个与病毒高亲和力的噬菌体克隆。接着经过抗病毒试验获得6个能强烈抑制病毒复制的阳性噬菌体克隆,能使病毒TCID50下降5个数量级。通过对阳性噬菌体克隆随机插入区域的核苷酸序列分析,推导出多肽的氨基酸序列。发现6个能强烈抑制病毒复制的阳性克隆中多肽的氨基酸序列完全一致(NH2LeuTrpValGlyGlyGlyArgAsnAla),该结果提示多肽的抗病毒能力与多肽特异性氨基酸组成及结构有关。因此,抑制GCHV873复制特异性多肽的氨基酸序列的确定及结构分析,不仅为人工合成抗草鱼出血病病毒的多肽奠定了基础,同时也为抗病毒多肽制剂的研制提供了依据。  相似文献   

2.
草鱼出血病病毒多肽的荧光染色   总被引:1,自引:0,他引:1  
王炜  陈延 《Virologica Sinica》1994,9(2):157-159
将草鱼出血病病毒(GrassCarpHemorrhageVirus,GCHV)置于还原性的溶液中,然后加入等体积的NaHCO3配制的异硫氰酸荧光索溶液进行多肽的标记,再经SDS-PAGE分析,在紫外灯下即可检测到GCHV全部的11个结构多肽的荧光带。该方法最小检测量为500ng,由该方法回收的多肽具有抗原活性,可作为抗原进行免疫学实验。  相似文献   

3.
报道了一种从噬菌体肽库中筛选胰凝乳蛋白酶短肽抑制剂的新方法.在通常的亲和富集筛选的基础上,利用胰凝乳蛋白酶自身的水解活力切割掉结合的底物噬菌体,再经抑制活力分析得到抑制性噬菌体克隆.这样筛得的噬菌体克隆具有明显的胰凝乳蛋白酶结合活力和抑制活力,DNA序列分析发现其保守序列为(S/T)RVPR(R/H).按此序列化学合成的短肽Ac-ASRVPRRG-NH2、Ac-ASRVPRHG-NH2同样表现出对胰凝乳蛋白酶的抑制作用.该方法为蛋白酶短肽抑制剂的筛选提供了一条有效途径  相似文献   

4.
酷氨酸蛋白激酶受体EphB2的Ig类似区,克隆到融合表达闰载体pET28a中,阳性克隆经IPTG诱导,表达出氨基端带6个连续组氨酸残基的融合蛋白。利用Ni-NTA金属螯合亲和层析法有变性条件下对表达的蛋白进行纯化,纯度大于94%。以此纯化蛋白为靶,将其包被于ELISA板上,经过三轮亲和筛选,从噬菌体随机7肽库中筛选到19个具有EphB2活性的重组噬菌体克隆,对阳性噬菌体克隆的短肽序列进行了分析。  相似文献   

5.
抗天花粉蛋白单抗T8C12针对的抗原表位的判定   总被引:4,自引:0,他引:4  
Western印迹结果表明抗天花粉蛋白(TCS)单抗T8C12能与CNBr裂解的TCS片段结合,氨基酸组成分析显示该表位位于N端72肽内。为进一步确定该表位的位置,用固定化的T8C12对克隆于噬菌体M13外壳蛋白pⅢ的随机六肽库进行了两轮亲和筛选后,随机测定了15个阳性克隆的DNA序列,发现插入的六肽序列有高度同源性,均含Ser/Thr-(X)-X-Arg结果,X代表疏水氨基酸。这一结构与天花粉蛋  相似文献   

6.
本文利用噬菌体随机9肽库探索汉滩病毒(HTNV)核衣壳蛋白(NP)B细胞抗原表位。以抗HTNV NP单克隆抗体(mAb)5H5作为筛选分子,生物淘洗噬菌体递呈的随机9肽库。阳性克隆经夹心ELISA、竞争ELISA鉴定后,随机挑取10个克隆,DNA测序,与HTNV76-118株S基因进行同源性分析。结果显示筛选到的噬菌体能特异地与5H5结合,这种结合可被天然抗原所抑制。10个克隆的氨基酸序列相同,均为VRDAEEQYE,与76-118株NP氨基端的aa25-33一致。证实了该线性表位是mAb 5H5识别的表位,噬菌体肽库有助于病毒抗原表位的确定。  相似文献   

7.
稀有鮈鲫对草鱼出血病病毒敏感性的初步研究   总被引:5,自引:0,他引:5  
本文报道稀有鲫对草鱼出血病病毒(GCHV)的敏感性。GCHV是草鱼出血病的病原,用GCHV人工感好1-6月龄的稀有鲫,在水温22-32℃时能导致稀有鲫出现出血病症状。在水温28℃时,病鱼在ld内死亡,潜伏期为5d,发病高峰期在感染后第6-8d。GCHV能在稀有鲫体内传代,并诱导80%以上的稀行鲫患病死亡。将人工感染GCHV的稀有鲫病鱼组织超薄切片,电镜观察,发现在肠道、脾脏、肾脏等组织中存在大小与形态和GCHV相似的病毒颗粒。从稀有鲫出血病病鱼组织中纯化病毒,免疫电镜观察,发现病毒颗粒能被GCHV的特异性抗体聚集成团。由上可知,稀有鲫出血病是由GCHV感染所致,稀有鲫对GCHV是敏感的,可以作为草鱼抗出血病育种的模型。  相似文献   

8.
β2糖蛋白Ⅰ(beta-2-glycoprotein Ⅰ,β2GPI)是一分子量为50 kD的糖蛋白.从抗磷脂抗体综合症(Antiphospholipid antibodies syndrom ,APS)患者身上获得的抗体可直接与β2GPI作用.以β2GPI为目标分子,在噬菌体十五肽库中筛选抗β2糖蛋白Ⅰ抗体的小肽抑制剂.通过四轮亲和性筛选,噬菌体的回收率从1.26×10- 4% 增加到3.19×10- 2% .随机挑取噬菌体克隆测定其与β2GPI的结合活性及其对β2GPI与自身抗体结合的抑制活性,其中部分噬菌体克隆表现出40% 的抑制活性.经DNA 序列测定,得到一组相关序列.该结果为研究β2GPI的抗原表位奠定了良好的基础.  相似文献   

9.
郑一敏  皮国华 《病毒学报》1995,11(2):107-113
将切去3'端穿膜序列的EB病毒膜抗原(MA)基因,插入pSV2-dhfr质粒的SV40早期启动子下游,构建了真核表达载体pSV2-dhfrGPTR,使两个SV40早期启动子分别调控MA和二氢叶酸还原酶(dhfr)基因。将该重组质粒转化CHO-dhfr细胞。在选择培养基中筛选阳性克隆,用氨甲喋呤加压扩增,建立了表达EBV-MA的克隆细胞系。Western bolt分析证明,所表达的蛋白的分子量大约为  相似文献   

10.
将含有鸡传染性支气管炎病毒 S1 基因c D N A 的重组转移质粒p S X I V V I+ X3 S1 . Holte 和p S X I V V I+ X3/4 S1 . Holte 分别与粉纹夜蛾核型多角体病毒 Tn N P V S V I- G D N A( O C C- ,gal+ ) 共转染草地夜蛾( Sf9) 细胞,经空斑纯化得到重组病毒 Tn N P V( X3) S1 . Holte O C C+ 和 Tn N P V( X3/4) S1 . Holte O C C+ 。将重组毒株分别感染 Tn5 B1 细胞,并进行 S D S P A G E 与 Westernblot 检测。结果表明, Tn N P V( X3/4) S1 . Holte O C C+ 在感染的细胞中高效表达了 S1 蛋白, S D S P A G E 凝胶薄层色谱分析结果显示,感染病毒后72 h S1 蛋白的表达量占细胞内总蛋白量的35 .8 % ,而 Tn N P V( X3) S1 . Holte O C C+ 感染的细胞内检测不出 S1 蛋白。经分析认为这一差异主要来自 S1 基因翻译起始位点及其附近的周围环境。  相似文献   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

13.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

14.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

15.
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.  相似文献   

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18.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.  相似文献   

19.
Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H2-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H2 with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD+, FMN+, and NAD(P)+ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H2OCO2+2H++2e- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation  相似文献   

20.
Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l−1 glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l−1) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.  相似文献   

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