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1.
根据酸性海藻糖酶的蛋白质序列设计引物,PCR扩增出CQMa102 ATM1的cDNA和DNA序列,登录号分别为:DQ237957,EF190950.序列分析表明,ATM1 DNA序列含有3个内含子,其开放阅读框(ORF)编码1个含1 073个氨基酸的蛋白质,具有1个20个氨基酸的信号肽序列和含有30个可能的N-糖基化位点(Asn-Xaa-Ser/Thr).NCBI序列比对(Blastn)显示该蛋白与Aspergillus fumigatus的alpha、alpha-trehalose glucohydrolase,Aspergillus nidulans的酸性海藻糖酶前体和Talaromyces emrsonii的酸性海藻糖酶分别有62%、59%和57%的氨基酸相似性,与另外两个真菌Saccharomyces cerevisiae(Ath1p)和Candida albi-cans(Atc1p)的酸性海藻糖酶也具有约25%的氨基酸相似性.Southern杂交表明,ATM1基因在CQMa102基因组中为单拷贝.  相似文献   

2.
为了解牛樟芝三萜类生物合成、调控机理,以多孔菌科真菌茯苓(Wolfiporia cocos,AFR13032.1)的SQS基因为模板对牛樟芝基因组数据进行本地Blast,分离获得牛樟芝鲨烯合酶(AcSQS)基因.以该序列为模板设计特异引物Ac SQSF0和Ac SQSR0,通过PCR扩增得到Ac SQS c DNA全长,并对其进行生物信息学分析,检测不同碳氮源添加物的培养基上该基因的表达水平.结果显示:克隆得到的基因为牛樟芝鲨烯合酶(Ac SQS),该基因含4个外显子,3个内含子,外显子拼接总长1 803 bp,编码600个氨基酸;其蛋白序列的1~17位为信号肽位点,具两段跨膜结构,可能定位于内质网;位于该蛋白189~204位的CHYVAGLVGEGLTRL和225~238位的MGLMLQKTNIIRDY的保守基序为鲨烯合酶识别位点,DTIEDD和D(Y/F)RED为FPP绑定位点;蛋白网络分析显示其位于三萜类化合物的代谢网络中;聚类分析显示Ac SQS蛋白和茯苓、硫磺多孔菌、拟蜡菌、灵芝、云芝等的SQS蛋白聚为一支;不同碳氮源添加物培养基上的表达分析显示:果糖诱导该基因表达的能力最强,而不同氮源添加物诱导该基因表达的能力无明显差异.  相似文献   

3.
以暗紫贝母的法呢基焦磷酸合酶氨基酸序列为研究对象,利用CD search、ProtParam和SignalP等13种在线预测软件对其保守区域、理化性质、亚细胞定位、亲疏水性、二级结构、三级结构等性质进行分析.结果发现,该酶由352个氨基酸残基组成,是一种不含信号肽不跨膜、定位于线粒体基质的可溶性亲水蛋白,具有典型的类异戊二烯合成酶超家族结构域.其二级结构主要由α-螺旋和无规则卷曲组成.三级结构以PDB ID 4kk2.1为模板建模,包含两个聚异戊烯合酶位点,200 Lys为其结合配体Mg~(2+)的结合位点,活性区域由55个氨基酸残基构成,面积和体积分别为1 215.670?~2和1 496.051?~3.生物信息学手段分析预测结果揭示了暗紫贝母中法呢基焦磷酸合酶的性质、结构和功能,为进一步研究贝母活性生物碱的生物合成调控机制奠定理论基础.  相似文献   

4.
1-氨基环丙烷-1-羧酸合酶(1-aminocyclopropane-1-carboxylate synthase,ACS,EC 4.4.1.14)是乙烯生物合成过程的限速酶,对乙烯在高等植物体内的代谢调控具有至关重要的作用.本文通过系统发育分析和序列比对研究,鉴定出陆地棉基因组共编码22个GhACS基因,其编码蛋白含有7个与功能密切相关的保守基序,C末端具有多个潜在的Ser磷酸化位点;GhACS基因组织表达分析显示每个GhACS在棉花不同组织不同发育阶段表现出不同的基因表达谱,这些结果为进一步探究陆地棉GhACS基因家族的功能提供了有力的依据和参考.  相似文献   

5.
以草酸青霉SJ1菌株的基因组DNA和总RNA,利用PCR和RT-PCR技术进行扩增得到外切葡聚糖酶CBHⅠ(ExocellobiohydrolaseⅠ)基因的序列.CBHⅠ基因DNA序列全长1 638 bp,无内含子,编码545个氨基酸的多肽,推测其蛋白分子大小约为57 ku,蛋白的p I值为4.90.预测结果表明,CBHⅠ是一种很强疏水性的蛋白,具有43个磷酸化修饰位点,蛋白质三级结构以β-折叠为主,根据蛋白质序列比对分析,推测E236、D238和E241这3个氨基酸为酶的活性位点,为后续利用分子改造方法提高青霉产纤维素酶的能力提供理论依据.  相似文献   

6.
由蛋白质序列预测蛋白质功能位点对于理解蛋白质功能具有重大的意义,它同时也为生物学实验提供了重要依据.长期以来,基于知识库的方法一直是预测蛋白质功能位点的可靠方法.通过适当修改蛋白质结构分类库SCOP构建了一个附带功能注释的结构域模版库(fDPD),其中每个模版都包含一组序列和结构都非常相近的已知的蛋白质成员.fDPD通过隐马尔可夫模型方法HMMER由未知蛋白质的序列预测其功能位点.为了考察本方法的效果我们检测了两个通用的酶催化位点数据库,一个由约1 500个序列构成的钙离子结合蛋白数据库和从CASP9中提取出的数条蛋白质序列.我们的方法对于配体结合位点以及钙结合位点的预测取得了较高的精度和覆盖率,其催化位点的预测效果仅次于目前已知的最好的方法.我们的计算结果表明,结构上相似的蛋白质其功能位点倾向于出现在蛋白质表面上相似的位置.  相似文献   

7.
目的:克隆阳春砂倍半萜合酶(AvTPS)编码序列,并对其蛋白进行表达和纯化.方法:根据转录组测序获得的倍半萜合酶(TPS)核苷酸序列设计引物,以反转录生成的cDNA为模板,使用RT-PCR克隆获得AvTPS的编码(CDS)序列,并连接pMD-18T载体上,对阳性菌进行基因测序.利用ClustalX等生物信息软件对AvTPS蛋白氨基酸序列进行生物信息学分析.利用表达载体pSDS233, Ni-NTA亲和层析对蛋白表达和纯化.结果:通过RT-PCR获得了大小为1 650 bp的AvTPS的CDS序列并成功连接到pMD-18T载体.生物信息分析表明,AvTPS蛋白含549个氨基酸残基,二级结构以α-螺旋为主等信息.通过蛋白的表达和纯化,获得纯度为94.22%的可溶性AvTPS蛋白.结论:从阳春砂中可成功克隆出AvTPS的编码基因,为后续研究其基因在阳春砂中的特异性表达奠定基础.  相似文献   

8.
在日本鳗鲡(Anguilla japonica)中克隆获得2个γ-干扰素诱导的溶酶体巯基还原酶(GILT)基因AjGILT-1和AjGILT-2,并对其序列进行生物信息学分析,进而利用实时荧光定量PCR分别检测2个基因在不同组织器官中的表达水平,及其在脂多糖(LPS)、聚肌胞苷酸(PolyI:C)刺激和迟缓爱德华氏菌(Edwardsiella tarda)感染后的表达变化.结果显示:2个基因编码的蛋白序列中均含有GILT家族的特征序列CQHGX2ECX2NX4C、活性位点CXXC、2个糖基化位点和11个保守的半胱氨酸残基,基因组序列均含7个外显子和6个内含子.2个基因启动子中都存在多个转录因子结合位点,如γ-干扰素活化位点以及特化蛋白1结合位点;不同的是AjGILT-1启动子区存在多个核因子-1、激活蛋白-1结合位点及干扰素刺激反应元件,而在AjGILT-2启动子区未发现.AjGILT-1在鳃和肠中表达量最高,而AjGILT-2在性腺、头肾和脾脏中表达量最高;除肠道外,同一组织中AjGILT-2的表达量均高于AjGILT-1.LPS、PolyI:C刺激和E.tarda感染后,AjGILT-1与AjGILT-2的表达在鳃中仅有少数变化,而在头肾和中肾中则变化较明显.综上所述,AjGILT-1和AjGILT-2基因可能参与了日本鳗鲡受病毒和细菌感染后的免疫应答.  相似文献   

9.
利用比较基因组学方法,通过小麦TaNAM基因序列来设计引物,在早衰水稻品系金23B中寻找TaNAM的同源基因.对获得的c DNA片段进行序列比对分析,发现其与丙酮酸磷酸双激酶(Pyruvate phosphate dikinase,PPDK)基因高度同源,因此将其命名为OsPPDK(Oryza sativa PPDK).为进一步探索OsPPDK基因的功能及其与叶片衰老的关系,根据水稻预测OsPPDK基因序列设计特异性引物,利用RT-PCR技术克隆出OsPPDK基因的编码区,并进行生物信息学分析.结果表明:该基因全长为3 515 bp,包含一个完整的ORF,编码区长2 844 bp,编码947个氨基酸,分子量为102. 79 k D,所编码的氨基酸序列与其他已知的植物来源的PPDK基因相比,相似性大多在80%以上.在PPDK基因所编码的氨基酸序列中,发现了一个PEP利用酶位点信号,3个N-糖基化位点和15个酪蛋白激酶II磷酸化位点,12个蛋白激酶C磷酸化位点,2个酪氨酸激酶磷酸化位点和一个PEP利用酶位点.同时推测出多肽链中有规则重复的构象,并同源建模PPDK蛋白整条肽链的三维空间结构.  相似文献   

10.
为研究青藏高原特有鸡种,藏鸡的生物学特性,从藏鸡垂体组织的RNA中克隆POU1F1基因,并利用生物信息学对其进行分析.结果显示,藏鸡POU1F1基因开放阅读框(ORF)长为984bp,编码327个氨基酸.编码序列中有13个丝氨酸(Ser)、2个酪氨酸(Tyr)、6个苏氨酸(Thr)磷酸化位点;1个N糖基化位点;二级结构主要由α-螺旋和无规则卷曲构成;藏鸡POU1F1氨基酸序列与红色原鸡POU1F1氨基酸序列的亲缘关系最近.藏鸡POU1F1基因氨基酸序列可能与藏鸡生长速度慢的特性相关.这一研究结果为今后的藏鸡育种工作提供重要的靶点和参考.  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.
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   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  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.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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