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1.
应用基因工程技术,将EGF、GM-CSF基因克隆到pGEM-3Zf(+)载体的EcoRI,BamHI位点上,再将重组融合基因亚克隆到表达载体pBV220的EcoRI,BamHI位点上,在大肠杆菌DH5α中进行表达,SDS-聚丙烯酰胺凝胶电泳和Westernblot表明EGF-GM-CSF融合蛋白获得表达,并且具有EGF、GM-CSF的免疫学活性.这为进一步研究该融合蛋白的功能和肿瘤治疗提供一种新的基因产品.  相似文献   

2.
应用基因工程技术,将EGF,GM-CSF基因克隆到pGEM-3Zf载体的EcoRI,BamHI位点上,再钭重组融合基因亚克隆到表达载体pBV220扔EcoRI,BamHI位点上,在大肠杆菌DH5α中进行表达,SDS-聚丙烯酰胺凝胶电泳和Western blot表明EG-FGM-CSF融全蛋白获得表达,并且具有EGF,GM-CSF免疫学活活。  相似文献   

3.
丙型肝炎病毒核心蛋白基因在大肠杆菌内的表达及应用   总被引:2,自引:0,他引:2  
将从中国丙肝病人血清中扩增克隆的丙型肝炎病毒核心蛋白基因(408bp)酶切处理后插入表达载体pJLA502内,获得高表达核心蛋白的重组工程菌。将重组菌经42℃热诱导5h,SDS-PAGE分析表明,表达的核心蛋白占菌体蛋白总量的20%。经分子筛和吸附层析纯化后获得的核心蛋白,ELISA检测证实有较好的抗原性和特异性。用表达的核心抗原加用表达的NS_3抗原(C_33)装配的抗-HCV试剂盒,经用标准血清验证及与国外第二代抗-HCV试剂盒比较,证实符合丙肝诊断试剂要求。  相似文献   

4.
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   

5.
采用聚合酶链反应(PCR)技术和DNA体外重组方法,克隆出579bp的丙型肝炎病毒(HCV)NS4b基因片段,插入到原核高效表达载体pET-28a中,构建重组质粒pET/NS4b,转化大肠杆菌BL21(DE3)菌株,经IPTG诱导培养后,获得了目的蛋白的高效表达。SDS-PAGE分析显示在30kD处有一条表达的目的蛋白区带。通过固定化金属配体亲和层析(IMAC)纯化目的的蛋白,ELESA检测结果表  相似文献   

6.
应用逆转录-聚合酶链反应(RT-PCR)技术,从HCV感染者血清中扩增编码HCV病毒蛋白酶的NS2-NS3cDNA片段,在其5′和3′端分别引入EcoRⅠ和XbaⅠ限制性内切酶位点,定向克隆至真核表达载体pcDNA3,构建重组载体pcDNA-NS23,重组表达载体经限制性内切酶消化鉴定.用SP6和T7通用引物对目的基因片断进行序列分析.序列同源性分析结果表明,与HCV-J、HC-C2有高度的同源性,与HCV-1、HCV-J6、HCV-J8同源性差,提示所克隆的基因属HCVⅡ型.该区内重要的功能位点如Zn2+依赖性金属蛋白酶催化中心、丝氨酸蛋白酶催化中心等均高度保守  相似文献   

7.
通过逆转录(RT)-聚合酶链式反应(PCR),从中国人丙型肝炎病毒(HCV)携带者的血清中扩增并克隆到2段cDNA片段,即HCV基因组C区抗原基因C831cDNA片断(约530bp)和NS3区抗原基因C33ccDNA片段(约860bp)。C33ccDNA片段同C831cDNA片段经连接   肽Ser-Pro-Gly-Ser连接成为基因嵌合体C33c-C831(约1400bp)。C33c-C831基因嵌合体同温控型原核表达载体pBV220重组,构建成表达质粒pBV/C33c-C831,并在大肠杆菌细胞中获得了重组嵌合抗原C33c-CL的表达。通过酶切分析和Western免疫印迹法,对约占菌体可溶性蛋白9%的表达产物做了鉴定。采用TritonX-100和盐析处理,获得粗提表达产物。粗提的表达产物经尿素裂解和离子交换层析纯化,得到可用于检测抗HCV核壳蛋白和抗NS3区抗体的重组嵌合抗原C33c-CL。对C33c-CL做抗原性分析发现,它同时具有完整的C33c抗原和C22抗原的免疫反应活性,完全能替代单纯的C33c和C22抗原。该嵌合抗原在血清学诊断中有重要的应用价值,可望成为新一代HCVEIA诊断试剂的优选抗原。  相似文献   

8.
新型HCV EIA诊断试剂盒的研制   总被引:3,自引:0,他引:3  
杨永平  曹经缓 《病毒学报》1994,10(2):118-127
丙型肝炎病毒(HCV)基因组结构区核壳蛋白(C)区抗原、膜蛋白E1和E2区抗原,以及非结构区NS3-NS5区抗原的区段,已经在原核细胞中获得有效的表达。同时,相应区段中的优势抗原表位肽也经化学合成法大规模地制备。HCV基因组上各区段抗原性的分析发现,由C区和NS3区分别编码的C抗原和C33c抗原是HCV基因组上两个优势抗原区段。其相应的抗体出现早(感染后6周可检出抗C33c抗体),阳转率高(约99%阳性检出率),特异性和重复性均优于其它区段抗原。以中国人HCV的C33c重组蛋白和分支状合成肽MAP-C-19为复合抗原,研制了适合我国抗HCV抗体检测的新型丙型肝炎病毒酶免疫测定(HCVELA)诊断试剂盒。它同当代美国Abbott/UBIHCVELA诊断试剂的符合率约98%,同加拿大YES公司HCVEIA诊断试剂的符合率约97.8%,阳性检出率提高了约2%,3次重复性达100%,表明其特异性、敏感性和重复性均达到了当代第二代JCVELA诊断试剂的水平。我国人群中抗HCV抗体的分布情况为:正常人群的检出率1%-2%;外科类住院病人检出率约28.8%;肝炎患者抗HCV阳性率为34.4%,慢活肝、肝硬化和重症肝炎患者  相似文献   

9.
将将城疫病毒(NDV)F48E8株融合蛋白基因导入鸡痘病毒(FPV)插入载体pEGF1175-1的P7.5启动子下游,得到转移载体pFG1175-1重组质粒。采用脂质体转染技术,将该质粒转染FPV282E株感染的鸡胚成纤维细胞(CEF)。,经过多次蓝斑筛选纯化,获稳定的重组病毒rFPV-NDF。间接免疫荧光试验表明,rFPV-NDF感染的CEF中表达了NDV的融合蛋白。用rFPV-NDF免疫的SF  相似文献   

10.
采用基于神经网络的算法预测了我们自行克隆的新的白血病相关蛋白EEN(extra elevennineteen, EEN)全长分子的二级结构,结果表明:EEN 蛋白可能有三个结构域,N 端由三段α螺旋和短β折叠组成,中间为四段α螺旋组成的四螺旋结构,C端为SH3结构域,类似于在受体酪氨酸激酶信号传导途径中起重要作用的SEM-5/GRB2 C端SH3结构域;利用同源蛋白结构模拟的方法,模拟了EEN SH3结构域的三维结构,结果表明:EEN SH3结构域与SEM-5/GRB2 SH3结构域具有相近的结构,构成脯氨酸结合区的氨基酸非常保守.上述结果提示:EEN 蛋白可能为新的信号蛋白,可能涉及新的信号传导途径或新的信号传导旁路,SH3结构域是其功能区域.  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.
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   

13.
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   

14.
15.
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   

16.
The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.  相似文献   

17.
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.
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   

20.
Fluid collected from hatching eggs of Haemonchus contortus contained a lipase which hydrolysed 2-naphthyl laurate (about 0·7 μmol naphthol freed /h/106 eggs). The fluid also hydrolysed l-leucinamide (about 2·3 μmol leucine freed/h/106 eggs). The fluid when added to normal or heated eggs caused ‘hatching’. ‘Hatching’ also occurred in exsheathing fluid from infective juveniles and in a preparation of pancreatic lipase containing leucine aminopeptidase. A purified mammalian leucine aminopeptidase in combination with several different lipases did not attack egg shells.The ‘spontaneous’ hatching of eggs of H. contortus was strongly inhibited by 1,10-phenanthroline, 10?3M, and this inhibition was reversed by Zn2+. However, the inhibition of ‘hatching’ of eggs in externally applied hatching fluid, or the hydrolysis of leucinamide in hatching fluid was generally less marked.  相似文献   

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