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1.
从杭州、兰州两地各一例乙型肝炎病毒(HBV)表面抗原阳性血清中提取病毒DNA,采取PCR技术扩增出前表面抗原(preS)基因片段,重组到质粒载体上,对该基因进行了全序列测定[GenBank索取号CpreS-HZAF325674;preS-LZAF325675].克隆的HBVpreS基因杭州分离物(preS-HZ)和兰州分离物(preS-LZ)全长522个核苷酸,编码174个氨基酸.preS-HZ与已发表的HBVadr亚型上海分离物[8]、北京分离物[9]、日本分离物[5]、HBVadw亚型[10]和ayw亚型[11]preS基因的核苷酸序列同源性分别为96.7%、96.2%、97.3%、88.7%和84.1%,氨基酸序列同源性分别为96.0%、94.9%、97.1%、85.1%和85.4%;preS-LZ与相应序列的核苷酸序列同源性分别为96.4%、96.2%、96.9%、88.7%、83.7%,氨基酸序列同源性分别为94.9%、94.9%、96.0%、85.1%、84.1%.分子进化分析(DNASTAR,1999)表明,克隆的两例HBVpreS基因属于adr亚型.preS-LZ与preS-HZ之间有两个核苷酸变异(对应两个氨基酸变异),相对于以上报道的序列二者含有四个特异的氨基酸突变位点.在免疫保护区内二者具有较好的保守性,可用于表达乙肝重组亚单位疫苗.  相似文献   

2.
甘油-3-磷酸酰基转移酶(GPAT)基因与植物抗冷性密切相关。克隆到的长柔毛野豌豆(Vicia villosa)GPAT基因的编码区完整的cDNA片段长1377bp,编码458个氨基酸残基,与蚕豆(Vicia faba)和豌豆(Pissum sativum)比较,其核苷酸序列的同源性分别为94.1%和93.3%,氨基酸序列的同源性分别为96.9%和98.0%。  相似文献   

3.
以甜菜坏死黄脉病毒(BNYVV)内蒙分离物的总RNA为模板,通过反转录和PcR扩增获得75kDa通读蛋白基因54kDa片段的目的片段。将其克隆到pGEM-7Zf(+)上并转化DH5α得到了含有完整s4kDa片段的重组子pGBW52。采用双脱氧终止法进行序列分析。结果表明内蒙分离物的54kDa片段全长为1509nt,与法国的F13分离物相比缺失了3个核苷酸。其核苷酸序列和由此推导的氨基酸序列的同源性分别为94.97%和96.42%.  相似文献   

4.
利用反转录-PCR方法扩增了吉林省猪瘟病毒(HCV)两个野毒株gp55基因的主要保护性抗原编码区,并将其克隆到pGEM-T载体中,然后用Sanger双脱氧法测定了其核苷酸序列,并推导了其氨基酸序列。将测定的这两个HCV野毒株的部分序列(350bp)与国内外已知的HCV序列进行比较,结果表明:这两个野毒株的核苷酸序列的同源性为94.9%,氨基酸序列同源性为97.4%,与1985~1992年意大利中部分离4个野毒株的同源性明显高于其它HCV毒株,核苷酸同源性分别为97.2%~98.3%和94.0%~949%,氨基酸同源性分别为98.3%~991%和97.4%~98.3%,而与我国的HCV标准强毒株即石门株的核苷酸同源性仅分别为83.1%和83.1%,氨基酸同源性仅分别为90.6%和91.4%。因此认为吉林省这两个野毒株与意大利中部的4个野毒株具有密切的关系,而与石门株很可能来源不同。  相似文献   

5.
呼吸道合胞病毒在北京地区分离株G蛋白的基因分析   总被引:5,自引:0,他引:5  
耿学辉  王之梁 《病毒学报》1996,12(4):317-322
从经单克隆抗体证实为A亚型的北京地区呼吸道合胞病毒(RSV)分离株B79中,用RT-PCRT扩增出编码G蛋白的基因片段,克隆至载体pTZ18R中,经核苷酸序列测定证明,我国北京地区分离的A亚型株B79与RSVA亚型原型株(A2株)G蛋白基因的核苷酸同源性为93.8%,核苷酸的有义突变率为65%,由核苷酸推导出氨基酸序列的同源性为89.6%,氨基酸的变异主要集中在胞外区一个高度保守区的两端,而胞内区  相似文献   

6.
蜱传脑炎病毒东北株E蛋白的核酸和氨基酸序列   总被引:2,自引:1,他引:2  
从我国东北林区死者脑组织中,分离到蜱传脑炎病毒HLJ-1株,测定了它的E蛋白基因序列和推导的氨基酸序列,以及E蛋白抗原位点反应图谱。将该株与远东亚型Sofyn株和中欧亚型Neuderfl株做了同源性比较,HLJ-1株与Sofyn株E蛋白基因的核苷酸及氨基酸的同源性分别为94.3%和98.8%;与Neudoerfl的核苷酸和氨基酸的同源性分别为83.7%和96%。在E蛋白的核苷酸序列中,HLJ-1和  相似文献   

7.
呼吸道合胞病毒北京地区分离株G蛋白的基因分析   总被引:5,自引:1,他引:5  
从经单克隆抗体证实为A亚型的北京地区呼吸道合胞病毒(RSV)分离株B79中,用RT-PCR扩增出编码G蛋白的基因片段,克隆至载体pTZ18R中。经核苷酸序列测定证明,我国北京地区分离的A亚型株B79与RSVA亚型原型株(A2株)G蛋白基因的核苷酸同源性为93.8%,核苷酸的有义突变率达65%。由核苷酸推导出氨基酸序列的同源性为89.6%。氨基酸的变异主要集中在胞外区一个高度保守区的两端,而胞内区和跨膜区相对保守。本文探讨了我国北京地区RSV分离株的G蛋白基因同原型株之间的变异,在疫苗研制中的意义。  相似文献   

8.
对1996年至2001年间自我国部分养鸡场发病鸡或死亡鸡分离鉴定的8株H9N2亚型禽流感病毒的非结构蛋白基因(NSl)进行了扩增和序列测定,并分析和比较了其核苷酸和氨基酸的同源性。结果表明:NSI基因核苷酸和氨基酸同源性分别为96.5%-99.5%和94.5-98.6%,说明NSl基因在遗传进化上高度保守,稳定遗传。与中国香港、韩国、巴基斯坦及人源H9N2分离株相比较,发现中国大陆的鸡源H9N2分离株的NSl基因在其羧基端缺少13个氨基酸。系统进化树分析表明,该8株病毒的NSl基因属于相同的进化分支,而且中国的早年分离株A/chicken/Beijing/1/94位于该进化分支的根部,暗示这些分离株的NSl基因是由A/chicken/Beijing/1/94演化而来;尚未发现NSl基因属于A/quail/HongKong/G1/97-1ike分支的分离株。同时,系统进化树也说明了我国的H9N2分离株与韩国、巴基斯坦等地的H9N2分离株隶属于不同的进化分支,H9N2亚型禽流感的发生和流行与地域有一定的相关性。  相似文献   

9.
水稻条叶枯病毒基因组组分3的克隆与序列分析   总被引:1,自引:0,他引:1  
利用RT-PCR技术,合成并扩增了水稻条叶枯病毒(RStV)中国云南分离 物基因组组分3的全长cDNA。将PCR产物克隆在载体pCRⅡ上,进行全序列测定。将所得核苷酸序列及其所推导的氨基酸序列与日本分离物T进行同源性比较,结果表明,在核苷酸水平上,两分离物的5’端非编码区序列相同,vORF、vcORF及基因间非编码区序列的同源性分别为97.6%、96.8%及87.6%,而3’端非编码区同源性为98  相似文献   

10.
根据GenBank中发表的山羊关节炎脑炎病毒CAEV-CO株(caprine arthritis encephalitis virus-CO,CAEV-CO)的全基因组序列(序列号:NC-001463),设计合成了7对引物,对CAEV甘肃株的全基因组进行了PCR扩增,并对扩增产物进行了克隆和测序。结果表明,CAEV-甘肃株基因组全长为9186nt。与国际标准毒株CAEV—CO株相比,在编码区有12个碱基的缺失,二者的核苷酸同源性为91.0%;在非编码区有27个核苷酸的插人,核苷酸同源性为97.0%。gag、pol、蛋白Q、tat、env基因编码的氨基酸同源性分别为94.6%、94.7%、87.9%、94.7%和91.5%。  相似文献   

11.
《环境昆虫学报》2014,(5):790-804
综述了白蚁螱客的主要种类、共生关系及相关机制的研究进展。白蚁螱客中,已报道的动物种类达170种。在与动物的共生关系中存在偏利共生(宾主共栖和异种共栖)、互利共生和无关共生三种;在与微生物的共生关系中,存在与内生菌(原生动物、细菌、真菌和放线菌)和外生菌(蚁巢伞菌等)间的互利关系。指出了白蚁与螱客研究中存在的问题,给出了解决方案,并提出了今后可能的研究热点或方向,为白蚁的综合利用(如纤维素酶)及今后研究物种间的协同进化提供了基础资料。  相似文献   

12.
New sulfur derivatives of phosphoramidite ligands were synthesized and the impact of the sulfur unit on the spectroscopic properties of their rhodium and iridium complexes was investigated. The new ligands Bn2NPSCH2CH2Sa(P-Sa) (Bn = benzyl, 4), Bn2NPSCHCHSa(CH2)3CaH2(P-Sa)(Ca-Sa) (6) and Bn2NP(4-XC6H4OMe)2 (X = S, 7a; X = O, 7b) were converted to the rhodium and iridium complexes trans-[Rh(CO)Cl(L)2] (L = 4, 6, 7), [RhCl(COD)(L)] (L = 4, 6, 7), [IrCl(COD)(7a)] and [IrCl2Cp∗(6)]. For comparison, some phosphoramidite complexes of these formulations also were synthesized. The new metal complexes were spectroscopically analyzed. For the carbonyl complexes, the νCO IR stretching frequencies were lower than for the corresponding phosphite and phosphoramidite ligands. The 1JPRh coupling constants for the rhodium complexes with the new ligands were also smaller than for the respective phosphoramidite and phosphite complexes. Finally, the 1JPSe coupling constants of the selenides of the new ligands were lower than those of the phosphoramidite ligands but higher than for PPh3. The spectroscopic data reveal that the new thio ligands 4, 6 and 7a are more electron donating than phosphites and phosphoramidites but less electron donating than PPh3.  相似文献   

13.
Astrocytes transport the monocarboxylate acetate, but synaptosomes do not. The reason for this is unknown, because both preparations express monocarboxylate transporters (MCT). The transport and metabolism of lactate, another monocarboxylate, was examined in these two preparations, and the results were compared to those for acetate. Lactate transport is more rapid in astrocytes than in synaptosomes, but of lower affinity (Kms of 17 and 4 mM, respectively). Lactate (0.2 mM) is metabolized to CO2 more rapidly in synaptosomes than in astrocytes (rates of 0.37 and 0.07 nmol x mg protein(-1) x min(-1), respectively). The reason for this is unclear, but cellular differences in lactate dehydrogenase isotype expression may be involved. Acetate is metabolized to CO2 more rapidly in astrocytes than in synaptosomes (rates of 0.43 and 0.02 nmol x mg protein(-1) x min(-1), respectively). This is likely due to cellular differences in the expression of monocarboxylate transporter subtypes.  相似文献   

14.
The first and second sessions of the Workshop focussed on the basics of ultrasound and infrasound, their applications in both industry and medicine, and metrology and protection standards for ultrasound applications.  相似文献   

15.
16.
To elucidate accumulation of minerals in human iliac arteries with aging, the content of minerals was analyzed by inductively coupled plasma atomic emission spectrometry. Bilateral common, internal, and external iliac arteries of 16 men and 8 women, ranging ages from 65 to 93 yr, were examined. It was found that an extremely high accumulation of calcium and phosphorus occurred in the common iliac artery at old age, being higher than that of the internal and external iliac arteries. It should be noted that the accumulation of calcium and phosphorus is the highest in the common iliac artery among the human arteries examined to date. Regarding sexual differences, the content of calcium and phosphorus in the common and internal iliac arteries was higher in women than in men, whereas their content in the external iliac artery was lower in women than in men.  相似文献   

17.
18.
The ability of partially purified human and guinea-pig haematogenous cell populations, when cultured in vitro, to metabolise arachidonic acid (AA) has been studied. Supernatants from 24 hour cell culture have been subjected to analysis for products of AA metabolism by gas chromatography with electron-capture detection.The cell types studied were human peripheral blood monocytes (both glass adherent and non-adherent), neutrophils, eosinophils and leukemic leucocytes; thoracic duct lymphocytes and lung alveolar macrophages. From the guinea-pig, induced and non-induced macrophage or neutrophil enriched peritoneal exudate populations, lymph node cells, peritoneal eosinophils and peripheral blood platelets were examined. Supernatants were assayed for the presence of PGE2, PGD2, PGF, TXB2 and 6-keto-PGF. In all types studied PGE2 and TXB2 were the major products formed. The identification of PGE2 and TXB2 was confirmed by GC/MS with multiple ion monitoring.The results have been compared with other reports and their possible significance discussed in relation to the proposed role of prostaglandins as mediators and modulators in immunopathology.  相似文献   

19.
Allergic asthma can be precipitated by many factors. For the atopic person, fungus, pollen, dust mites, cockroach antigens, and diesel exhaust are all agents that may trigger an allergic attack. Cytokines and chemokines are integral mediators of fungal asthma. From the earliest time points, they recruit and activate the cells required for the clearance of fungus as well as being critical factors involved in the immunopathology of this disease. In the final analysis, it is clear that these mediators can act to the benefit or the detriment of the host.  相似文献   

20.
In spite of the many studies on protein modifications by reactive species, knowledge about the products resulting from the oxidation of protein-aromatic residues, including protein-derived radicals and their stable products, remains limited. Here, we compared the oxidative modifications promoted by peroxynitrite and myeloperoxidase/hydrogen peroxide/nitrite in two model proteins, ribonuclease (6Tyr) and lysozyme (3Tyr/6Trp). The formation of protein-derived radicals and products was higher at pH 5.4 and 7.4 for myeloperoxidase and peroxynitrite, respectively. The main product was 3-nitro-Tyr for both proteins and oxidants. Lysozyme rendered similar yields of nitro-Trp, particularly when oxidized by peroxynitrite. Hydroxylated and dimerized products of Trp and Tyr were also produced, but in lower yields. Localization of the main modified residues indicates that peroxynitrite decomposes to radicals within the proteins behaving less specifically than myeloperoxidase. Nitrogen dioxide is emphasized as an important protein modifier.  相似文献   

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