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1.
用PCR方法合成了人表皮生长因子(hEGF)基因,构建了原核表达质粒p 20T-hEGF,研究了原核表达的重组蛋白hEGF的生物学活性,并构建了植物表达质粒,研究表明:无论是融合蛋白GST-hEGF或纯化的hEGF蛋白,都有相当高的生物活性,hEGF蛋白对Hela细胞的增殖有很好的促进作用,免疫小鼠亦能产生很高的免疫应答反应。  相似文献   

2.
猪呼吸道冠状病毒核衣壳蛋白基因的克隆及原核表达   总被引:2,自引:0,他引:2  
以RT—PCR法从猪呼吸道冠状病毒(PRCV)感染的ST细胞中得到核衣壳蛋白(N蛋白)cDNA,并以此为模板利用PCR技术完成了N蛋白的基因扩增.通过双酶切、连接、转化等过程构建了猪PRCVN蛋白基因的重组原核表达质粒,表达产物经SDS—PAGE、Western blot检测被确认为GST融合的N蛋白.表达蛋白与PRCV阳性血清间有良好的免疫结合性.  相似文献   

3.
目的:为制备重组小鼠Pem(以下简称mPem)-谷胱甘肽巯基转移酶(GST)融合蛋白,作为研究mPem蛋白功能的材料,方法:根据携带小鼠Pem基因编码序列的模板质粒pEGFP/mPem设计合成特异性引物,PCR扩增小鼠Pem基因编码序列,并插入融合蛋白原核表达载体pGEX-4T-3中,得到重组表达质粒pGEX-4T-3/mPem,用此重组质粒转化大肠杆菌BL21细胞,IPTG诱导重组菌表达mPem蛋白,SDS-PAGE及Western Blot鉴定表达产物。结果:重组菌株明显诱导表达出预期相对分子质量49000的融合蛋白。结论:成功构建了mPem-GST原核表达质粒,并在大肠杆菌中表达出mPem-GST融合蛋白,为mPem蛋白功能的研究打下了基础。  相似文献   

4.
目的:在大肠杆菌中高产表达人表皮生长因子(hEGF),并探索提高外源基因在pET-3c:BL(DE3)表达系统的表达水平的途径。方法:根据大肠杆菌对密码的偏爱性,合成编码53个氨基酸的hEGF基因,分别以非融合蛋白和融合蛋白两种方式表达。计算机两者mRNA的翻译起始区(translation initiation region,TIR)的结构。结果:融合蛋白表达产量为27%,非融合蛋白的表达用SDS-PAGE检测不到,两者均具有促细胞增殖的活性。融合蛋白mRNA的TIR的△G值较非融合蛋白的高。结论:在pET-3c:BL21(DE3)大肠杆菌表达系统中,以融合蛋白方式表达人表皮生长因子,表达效率高且不影响其活性,此外,mRNA的TIR的结构可能是影响外源基因在本研究的表达系统的表达效率的一个重要因素。  相似文献   

5.
His-猪生长激素融合基因在Bm-N细胞和蚕体内的表达与纯化   总被引:1,自引:0,他引:1  
用构建的带有His—Tag pgh融合基因的重组杆状病毒Bm—BacPAK6—pgh研究了Bm—BacPAK6—pgh在家蚕细胞(Bm—N)和蚕体内的表达,并对蚕体表达产物进行了纯化.SDS—PAGE电泳分析显示,重组病毒Bin—BacPAK6—pgh在Bin—N细胞、蚕体中得到了融合表达,Western blot分析表明,Bm—N细胞、蚕体中表达的融合蛋白与大肠杆菌表达的猪生长激素具有相同的抗原性.Bm-BacPAK6-pgh在Bin—N细胞内的表达始于24h,而蚕体中的表达始于72h,二者的表达峰分别在96h和120h.经40%饱和度硫酸铵盐析和Ni—NTA Agarose亲和柱二步纯化可获得SDS—PA(正电泳纯的具有抗原性的重组猪生长激素融合蛋白。  相似文献   

6.
大肠杆菌caiE基因的克隆与高效表达   总被引:1,自引:0,他引:1  
用聚合酶链反应(PCR)从大肠杆菌K12s中扩增大肠杆菌肉碱代谢相关酶基因cai E,将其克隆到克隆载体pBluescripy SK中,测序表明:该基因有612bp,与文献报道相比,有10个核苷酸不同,相应的翻译氨基酸有6个相异,将该基因重组到ColE1为复制子,T7为启动子控制下的分泌型表达载体pET-22b( )中,构建表达质粒pETCaiE,重组到载体pACYC184中构建以p15A为复制子,Lac为启动子的表达质粒pACYC-CaiE;重组到载体pWSK129中,构建以pSC101为复制子,T7为启动子的表达质粒pSC-CaiE。上述表达质粒转化大肠杆菌BL21(DE3),经1mmol/L异丙基硫代-β-D-半乳糖苷(IPTG)诱导后,均可表达,SDS-PAGE分析表明表达蛋白分子质量约26ku,表达量占菌体总蛋白质的比例分别为pETCaiE30%,pACYC-CaiE8%,pSC-CaiE5%。  相似文献   

7.
目的 构建SarA的原核表达载体,对SarA蛋白免疫原性进行初步研究.方法 首先应用生物信息学方法 对SarA基因进行分析;以金黄色葡萄球菌基因组为模板,通过PCR扩增、酶切、连接等一系列反应进行原核重组质粒的构建;IPTG诱导原核重组质粒表达,对SarA蛋白进行纯化、浓缩,将浓缩后的蛋白与佐剂混合免疫家兔,收集血清,通过间接ELISA法检测血清抗体效价,并通过Western blot鉴定抗体特异性.结果 成功构建重组表达质粒SarA-pET32a(+),通过IPTG诱导表达,获得以可溶形式高效表达的SarA蛋白,分子质量约为32 kDa.用纯化的SarA蛋白免疫家兔,获得了SarA多克隆抗体,其效价为1:512000.结论 成功构建了SarA原核表达载体,且在大肠杆菌细胞中表达;得到了高效价和良好特异性的多克隆血清抗体,为进一步研究抗细菌生物膜疫苗奠定了基础.  相似文献   

8.
采用重组小鼠凝血因子Ⅸ制备单克隆抗体的研究   总被引:2,自引:0,他引:2  
将小鼠凝血因子Ⅸ (mFⅨ )cDNA蛋白编码区序列克隆至原核表达载体 pQE30 ,在大肠杆菌M 15中获得高效表达 (约占细菌蛋白总量的 5 1 2 % ) ,并经过SDS PAGE纯化获得均一的重组mFⅨ蛋白 .以此蛋白为抗原 ,免疫Lou/MN系大鼠 ,取其脾细胞与小鼠骨髓瘤细胞 (Sp 2 / 0 )融合后 ,经 3次克隆化选择获 2株杂交瘤细胞(H4B5和C2B10 ) .以 1× 10 6杂交瘤细胞注射免疫缺陷型裸鼠 ,10d后获得腹水 .对此单抗的功能和特异性初步研究表明 ,所制备的抗小鼠FⅨ单抗可用于Western免疫印迹等研究 .  相似文献   

9.
从牛泡沫病毒BFV3026感染的胎牛肺细胞中提取Hirt DNA,PCR扩增BFV3026 gag基因。序列分析确证后,将其克隆于原核表达载体pET32A,重组质粒转化大肠杆菌BL21(DE3),经IPTG诱导,使Gag蛋白得以高效表达。SDS-PAGE及Western blot证实:表达蛋白占菌体总蛋白的40%,本工作的完成为Gag蛋白功能的研究奠定基础。  相似文献   

10.
采用BAC-TO-BAC杆状病毒表达载体体系构建了表达鸡传染性支管炎病毒(IBV)呼吸型毒株SD/97/01S1蛋白的重组杆病病毒,含SD/97/01株S1基因原重组质粒p MDSD9701S1用BamHI和SalI双酶切后,回收的片段并克琶杆病病毒转座载体pFASTBACHTa中多角体基因启动子的下游,筛选出重组转座质粒pFASTSD9701S1U并转化大肠杆菌DH10BAC后,获得重组穿梭质粒rBacmidSD9701S1,用重组穿俊质粒DNA转染昆虫Sf9细胞,获得了含SD/97/01S1基因的重组杆状病毒rAcSD9701S1,重组病毒感染Sf9细胞后,用SDS-PAGE、Westernblot和IFA对细胞表达产物进行检测和分析。结果表明:构建的重组杆状病毒能够在昆虫细胞中表达SD/97/01的S1蛋白,该蛋白具有天然蛋白的抗原性。  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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