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猪圆环病毒2型ORF3基因的原核表达 总被引：1，自引：1，他引：0
用原核表达系统表达猪圆环病毒2型ORF3基因,分析ORF3蛋白的抗原性。根据GenBank上公布的猪圆环病毒2型(PCV-2)核苷酸序列进行分析,针对ORF3基因设计并合成1对特异性引物,PCR扩增该基因,并将此片段克隆入原核表达载体pET-32a(+)上,命名为pET32a-ORF3,转化大肠杆菌Rosetta-blue(DE3) pLacⅠ感受态细胞,1.0 mmol/L IPTG 37 ℃诱导表达。结果表明,PCR扩增得到315 bp的片段,重组蛋白大小约为29 ku,与预期大小相符。Western blotting分析结果表明,重组蛋白能与抗His-tag的单克隆抗体反应,不与PCV-2阳性血清发生反应。猪圆环病毒2型ORF3基因能在大肠杆菌中成功表达,但与阳性血清之间没有反应原性,为进一步研究PCV-2 ORF3蛋白的功能及特性奠定基础。 相似文献
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《中国兽医杂志》2017,(10)
为研究猪圆环病毒2型(PCV-2)ORF3蛋白的免疫活性,对其进行了表达及初步鉴定。根据NCBI上PCV-2ORF3的基因序列(FR823451)设计特异性引物,扩增后将其插入pET28a表达载体构建了重组表达质粒pET-PCV-2-ORF3,转化E.coli BL21(DE3)诱导表达后用SDS-PAGE和免疫印迹进行了鉴定。随后又用圆环病毒野毒感染猪和重组ORF2免疫小鼠的阳性血清对表达蛋白的免疫原性进行了检测。结果表明,构建成功的pET-PCV-2-ORF3表达菌被诱导后能大量表达PCV-2 ORF3蛋白。ORF3表达蛋白能与圆环病毒野毒感染猪的阳性血清发生特异性反应,与重组疫苗免疫鼠的阳性血清不能发生反应,表明ORF3蛋白具有很好的免疫原性和反应原性,有望作为圆环病毒野毒感染检测的靶抗原。 相似文献
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利用PCR技术从临床病料中提取病毒DNA,扩增出猪圆环病毒PCV-2核衣壳蛋白(Cap)基因。将其克隆到原核表达载体pET-32a中,构建了表达载体pET-H2,转化至大肠杆菌BL21中,用ITPG诱导表达。SDS-PAGE分析显示,重组蛋白主要以不溶性包涵体形式表达,与预期大小30 ku相符;Western-blotting分析表明,表达产物能与抗猪PCV2阳性血清发生反应。 相似文献
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对所分离鉴定的猪圆环病毒2型(PCV-2)ZZ株,参照GenBank中PCV-2全基因序列,设计1对特异性引物,利用PCR扩增出PCV-2ORF2片段,原核表达载体pET-32a(+)获得重组质粒pET-ORF2,IPTG进行诱导表述,并进行Western blot分析。结果表明,PCR扩增产物长度为702bp,大小与预期的一致,成功构建重组质粒,经IPTG诱导成功获得分子质量约为30ku的表达蛋白,该蛋白具有很好的免疫原性,为进一步研制PCV-2疫苗提供依据。 相似文献
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为了研究猪圆环病毒2型(PCV-2)ORF2基因的免疫原性,试验采用PCR方法扩增PCV-2辽宁株去核定位信号的ORF2基因(ORF2-Ⅰ),将其克隆到表达载体pEGX-6P-1中,转化大肠杆菌BL21(DE3),经IPTG诱导表达。结果表明:表达产物经SDS-PAGE分析,可见1条长约47.0 ku左右的蛋白条带;Western-blot分析显示,该表达产物具有特异性,能与抗GST单克隆抗体发生特异反应。说明融合蛋白GST-ORF2-Ⅰ在大肠杆菌中的表达获得成功。 相似文献
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《畜牧与兽医》2020,(8)
试验旨在建立一种快速的猪圆环病毒3型(PCV3)抗体检测方法。采用PCR方法对PCV3 ORF2基因主要抗原区域进行扩增,并利用原核表达系统进行截短表达,以纯化后的重组蛋白作为包被抗原,建立间接ELISA抗体检测方法。结果显示:PCR扩增了片段大小为348 bp的ORF2基因主要抗原区域,PCR扩增产物克隆至pET-32a原核表达载体,转入大肠杆菌BL21,获得了以包涵体形式表达的重组蛋白,纯化后经Western blot鉴定表明具有良好的反应活性。以重组蛋白作为包被抗原建立了检测PCV3抗体的间接ELISA方法,对PCV3阳性血清的最低检出效价可达1∶20 480;用该方法检测猪圆环病毒2型(PCV2)、猪繁殖与呼吸综合征病毒(PRRSV)、猪瘟病毒(CSFV)、猪细小病毒(PPV)、伪狂犬病毒(PRV)、乙型脑炎病毒(JEV)、猪流行性腹泻病毒(PEDV)、猪传染性胃肠炎病毒(TGEV)等猪常见疫病阳性血清,结果均为阴性;批内重复性试验和批间重复性试验的变异系数均小于5%。应用该方法检测四川地区533份不同日龄临床猪血清样品,PCV3阳性感染率达14.82%。表明建立的ELISA方法具有良好的敏感性、特异性、重复性和临床适用性,为我国商品化PCV3血清学抗体检测试剂盒的研制奠定了基础。 相似文献
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根据GenBank猪圆环病毒2型基因序列,设计合成两对特异性引物,对厦门株-1进行PCR扩增,得到ORF1和ORF2基因。将PCR产物酶切后,插入到pET-22b载体中,构建原核表达载体pET-22b/ORF1、pET-22b/ORF2,转化大肠杆菌BL21(DE_3),经IPTG诱导表达,收集茵液进行SDS-PAGE分析。确定重组蛋白主要以包涵体的形式表达,包涵体洗涤溶解后,采用Ni~(2 )离子金属螯合亲和层析柱纯化蛋白,逐步透析法进行复性。Western blot和ELISA分析结果表明Rep蛋白和Cap蛋白均能与猪圆环病毒2型阳性血清发生特异性反应。 相似文献
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根据GenBank中猪圆环病毒2型(PCV-2)ORF2基因序列,设计了1对引物,应用PCR从广西PCV-2的DNA扩增出ORF2基因,将ORF2基因克隆至真核表达载体pcDNA3.1( )载体上,获得重组质粒,经PCR酶切以及序列分析鉴定,表明插入的片段为ORF2目的基因,插入的位置、大小和阅码框均正确,成功构建了真核表达载体重组质粒pcDNA-PCV-ORF2。对阳性真核表达质粒pcDNA-PCV-ORF2大量抽提后,以每只小鼠0.2 mg免疫5周龄左右的雌性小鼠,然后用ELISA检测免疫小鼠血清中抗体的产生情况,同时进行pcDNA-PCV-ORF2的体内分布和安全性检测。结果表明,pcDNA-PCV-ORF2在小鼠体内广泛存在,产生了抗猪圆环病毒的特异性抗体,从第7天开始产生抗体,第28天抗体水平达到最高,抗体可维持7周以上,并具有良好的安全性。本研究通过对小鼠的免疫试验,产生了猪圆环病毒的特异性抗体,表明成功构建了能够在活体细胞中高效表达的真核表达载体,为进一步研究猪圆环病毒DNA疫苗奠定了基础。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献