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1.
利用启动子探针型质粒pKK232-8从卡介苗染色体DAN的BamHI酶切片段中克隆到4个具启动功能的DNA片段,测定各重组子对氯霉素(Cm)的抗性,其中含3.3Kb外源片段的重组质粒pBCG2大肠杆菌转化子在LM培养基上对Cm抗性可达170×10-6g/mL,作了该片段的限制性酶切图谱.对pBCG2利用SalⅠ位点,亚克隆出4种部分重叠的具启动功能的DNA片段,这4种重组质粒分别命名为pBCG2-1,pBCG2-2,pBCG2-6和pBCG2-8,并分析了其中插入片段的大小及其转化子对Cm的抗性.将pBCG2-2的SalⅠ外源片段插入到分枝杆菌启动子探针型穿梭质粒pEQ3,获得一个可在卡介苗中表达lacZ基因的重组子pEB22.斑点杂交实验证明,具有启动功能的DNA片段来源于卡介苗的染色体DNA.结果表明克隆到一个对大肠杆菌和卡介苗均具启动子活性的DNA片段  相似文献   

2.
质粒pGA46-4带有从谷氨酸棒杆菌染色体上分离到的有启动功能的片段,用PCR技术从pGA46-4中扩增了该片段的关键区域;启动子PGL,将该启动子经EcoRⅠ-BamH Ⅰ双酶切后,与大肠杆菌质粒pJL01的EcoRⅠ-BamHⅠ大片段连接,再接入Xyl E gene和棒状杆菌质粒pXZ10142,构建成棒状杆菌-大肠杆菌穿梭表达载体pJL23。用邻苯二酚双加氧酶基因检测表明,该表达载体可在棒状  相似文献   

3.
将具有广泛寄主范围的IncQ质粒pJRD215的Km基因片段删掉,置换进大肠杆菌抗砷质粒pUM3上的抗砷基因及P1启动子片段,构建成新的抗砷质粒pSDR941,为12.4kb,通过接合的方式将其转移到氧化硫硫杆菌中并获得了表达。  相似文献   

4.
利用分子生物学方法,以含人结核杆菌热休克蛋白(HSP)70基因全长序列的质粒pMT-70为模板,扩增出hsp70启动子,将其定向克隆于pUC-19,构建成重组质粒pY6013;然后以重组质粒pIJK-1为模板,扩增出分枝杆菌α信号肽基因并将其克隆到pY6013闰中hsp70启动子的下游,得到了大肠杆菌-分枝杆菌表达质粒pY-α。  相似文献   

5.
透明颤菌血红蛋白基因在苏云金杆菌中的表达   总被引:4,自引:0,他引:4  
采用大肠杆菌与枯草杆菌的穿梭质粒pMK4作为载体,构建了含有果聚糖酶基因(sacB)启动子和vgb基因的重组质粒pMK-SV.通过原生质体和电转化,将pMK-SV转入苏云金杆菌中,经影印筛选得到转化子Bt4.对Bt4诱导表达,与原菌株相比Bt4的生长量增加了20.2%.  相似文献   

6.
将具有广泛寄主范围的IncQ质粒pJRD215的Kmr基因片段删掉,置换进大肠杆菌抗砷质粒pUM3上的抗砷基因及P1启动子片段,构建成新的抗砷质粒pSDR941,为12.4kb,通过接合的方式将其转移到氧化硫硫杆菌中并获得了表达,与对照菌相比,含质粒pSDR941的氧化硫硫杆菌的抗砷水平从15mmol/L提高到30mmol/L.  相似文献   

7.
PheAB基因在棒状杆菌染色体上的整合   总被引:1,自引:0,他引:1  
改造大肠杆菌质粒pLCX31,切除其中的xylE基因得到大肠杆菌质粒pJL01.将源于大肠杆菌分枝酸变位酶-预苯酸脱水酶基因2.3kb BamHI片段克隆到大肠杆菌质粒pJL01中启动子P32的下降,构建成质粒pJL02。再在pJL02的HindⅢ位点接入棒状杆菌染色体的HindⅢ消化的随机片段,构建成带不同棒状杆菌染色体片段而不带棒状杆菌自主复制顺序的棒状杆菌整合质粒pJL03。  相似文献   

8.
利用大肠杆菌质粒pUC18、pTG206和金黄色葡萄球菌质粒pC194在体外构建3个嵌合质粒pCC10、pCCT7和pST16.3个新质粒均是大肠杆菌和枯草杆菌的穿梭质粒。它们在大肠杆菌中呈Ap~rCm~r型,在枯草杆菌中则为Cm~rAp~5型。其中pCCT7和pST16含有xylE基因,可作为启动子探测质粒。所有的新质粒都具有来自pUC18的多酶克隆位点,适合于在大肠杆菌和枯草杆菌中重组外源DNA以及比较它们的表达情况。  相似文献   

9.
运用绿色荧光蛋白探讨肉葡萄球菌双精氨酸分泌途径   总被引:2,自引:0,他引:2  
根据肉葡萄球菌(Staphylococcus carnosus)TM300的基因组序列设计引物,经PCR扩增得到其tufA基因的启动子Peftu片段与大肠杆菌–葡萄球菌穿梭载体pBT2-Tat-GFP连接,构建了穿梭质粒pBT2-ETG.结果表明,穿梭质粒pBT2-ETG成功地转入大肠杆菌与肉葡萄球菌宿主中稳定表达具有活性的绿色荧光蛋白GFP,并被转运到肉葡萄球菌宿主的细胞壁,为进一步研究肉葡萄球菌双精氨酸(Tat)转运系统正确分泌其他外源蛋白奠定了实验基础.  相似文献   

10.
为构建结核杆菌PhoPR双组分系统PhoP、PhoR基因的重组穿梭质粒pMV361-PhoP、pMV361-PhoR并对其进行鉴定。采用结核分枝杆菌国际标准强毒株H37Rv菌株基因组DNA为模版,利用PCR技术分别扩增PhoP、PhoR基因编码序列,先克隆于T—Vector pMD19(Simple),再亚克隆至大肠杆菌-分枝杆菌穿梭表达载体pMV361,并转化E.coli DH5α感受态细胞,提取所得的阳性克隆子获得重组表达质粒pMV361-PhoP、pMV361-PhoR,通过PCR及双酶切鉴定。结果显示,结核分枝杆菌国际标准强毒株H37Rv菌株基因组DNA中扩增出的PhoP、PhoR基因与GenBank公布的序列一致,经过PCR及双酶切鉴定,表明PhoP、PhoR基因均成功插入了pMV361穿梭载体。由此可知,成功构建了重组穿梭质粒pMV361-PhoP、pMV361-PhoR,为进一步研究PhoPR双组分系统奠定了基础。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
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   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
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   

18.
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   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
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