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131.
牛支原体膜蛋白6种提取方法的比较研究 总被引:2,自引:0,他引:2
为筛选最佳牛支原体(mycoplasma bovis,Mb)膜蛋白的提取工艺,本试验以牛支原体W70株为代表,分别比较了4种浓度的TritonX-100 、TritonX-114、TritonX-100和TritonX-114;3种浓度碘化钾(KI)复合提取;反复冻融和超声裂解等6种Mb膜蛋白提取工艺和参数.各方法所获膜蛋白经SDS-PAGE和Bradford定量分析表明:不同方法的提取物中蛋白多肽和蛋白浓度各异;其中以3% TritonX-114和0.4%TritonX-100结合0.6 MKI两法提取的蛋白条带清晰度较好,蛋白浓度及蛋白收集率较高,蛋白多肽条数24~28条,蛋白相对分子质量分别在170 000~12 200和167 000~11 400之间;超声裂解及反复冻融法提取效果一般;而1.8 MKI法效果最差.研究发现3%TritonX-114或0.4 %TritonX-100结合0.6 MKI是Mb膜蛋白较优的提取方法. 相似文献
132.
综述了替米考星和罗红霉素等大环内酯类抗生素,沙拉沙星和二氟沙星等氟喹诺酮类抗菌药以及多西环素等四环素类抗生素在抗支原体上的应用与进展。 相似文献
133.
Mycoplasm suipneumoniae and Mycoplasma flocculare in comparative pathogenicity studies 总被引:1,自引:0,他引:1
N F Friis 《Acta veterinaria Scandinavica》1974,15(4):507-518
Three field strains of Mycoplasma suipneumoniae each inoculated into 3 gnotobiotic piglets produced macro- and microscopic lung lesions typical of enzootic pneumonia in 8 of the animals. Under similar conditions 3 strains of M. flocculare produced typical macroscopic lung lesions in just 1 out of 9 animals. It is therefore concluded that M. flocculare is not of primary etiologic importance in the porcine enzootic pneumonia complex.The frequency of successful reisolation from nasal cavities, lungs, and other tissues indicated that the lungs are the sole natural habitat for M. suipneumoniae, while for M. flocculare lungs as well as nasal cavities should be regarded as the natural habitat.None of the organisms apparently spread via the blood stream. M. flocculare, but not M. suipneumoniae, induced histologic alterations of the nasal mucosa. 相似文献
134.
135.
疫苗支原体检验中液体培养基保质期试验 总被引:1,自引:1,他引:0
介绍了病毒性活疫苗支原体检验用液体培养基冷冻保存的方法,在有效的保质期内,可提高支原体检验的速度和效率,保证检验工作的均一性和准确性. 相似文献
136.
P. Van Dijk L. Bos 《European journal of plant pathology / European Foundation for Plant Pathology》1985,91(4):169-187
Viral dieback of carrot, chervil, coriander, dill and wild Umbelliferae is described. Disease incidence in carrot crops grown for seed is often high but low in ware carrot. There is no secondary spread in carrot crops.The causal virus was identified as theAnthriscus strain of parsnip yellow fleck virus (PYFV) transmitted byCavariella aegopodii from cow parsley(Anthriscus sylvestris). Nicotiana benthamiana was practically indespensable for isolation of PYFV by sap transmission from plants with viral dieback.No immunity was found in 12 carrot cultivars or in wild carrot. Disease control with a systemic insecticide had limited effect.Carrot red leaf virus and carrot mottle virus were commonly found in carrot, but they did not cause dieback symptoms. Cucumber mosaic virus, parsnip mosaic virus and a virus resembling that of carrot yellow leaf were occasionally isolated from carrot. Symptoms due to mycoplasma were also observed.Samenvatting Bij de zaadteelt van peen is in ons land reeds lang een schadelijke, vroeg in het seizoen optredende instervingsziekte bekend als voorjaarsziekte of het zwart. Planten vallen op door necrose van jonge spruiten (insterving). Soms gaat meer dan de helft van het gewas verloren. Voor consumptie geteelde peen wordt echter nauwelijks aangetast. De ziekte is nu ook gevonden bij dille, kervel, koriander en wilde schermbloemigen.Uit zieke planten en ook vaak uit symptoomloze fluitekruidplanten werd een virus geïsoleerd waarmee de insterving kon worden gereproduceerd. Het werd herkend als de fluitekruid-(ofAnthriscus-)stam van pastinakegeelvlekvirus (PYFV) op grond van waardplanten, symptomen, serologie en overdracht doorCavariella aegopodii met als onmisbare helper hetAnthriscus-vergelingsvirus (AYV), dat ook in fluitekruid voorkomt. Het gebruik vanNicotiana benthamiana als toetsplant maakte isolatie uit planten met virusinsterving mogelijk. Voor de ziekte wordt nu de naam virusinsterving van schermbloemigen voorgesteld.Peenroodbladigheid veroorzaakt door peenroodbladvirus, dat meestal samengaat met peenvlekkenvirus, bleek ook algemeen voor te komen. Deze twee virussen spelen geen rol bij het veroorzaken van virusinsterving, zoals wel werd aangenomen. Beide ziekten zijn geheel verschillend in symptomatologie en epidemiologie. Incidenteel werden komkommermozaïekvirus, pastinakemozaïekvirus en een virus gelijkend op peengeelbladvirus in aangetroffen. Ook werd eenmaal een aan een mycoplasma toe te schrijven ziekte geconstateerd.Virusinsterving bleek epidemiologisch te kunnen worden verklaard door de massale jaarlijkse migratie vanC. aegopodii in het voorjaar, waarbij PYFV van fluitekruid naar peen en andere schermbloemigen wordt verspreid. Door onvatbaarheid van peen voor het helpervirus (AYV) treedt in dit gewas geen secundaire verspreiding op.In geen van 12 peenrassen en wilde peen werd resistentie aangetroffen. Toepassing van een systemisch insekticide bleek in eerder onderzoek slechts een beperkt effect te hebben. Peenzaadteelt in gebieden met minder bladluizen, zoals het noorden des lands, lijkt aan te bevelen, maar verder lijkt de ziekte niet te bestrijden.Work in partial fulfillment of requirements for master's training at Agricultural University, Wageningen 相似文献
137.
试验旨在研究肺炎克雷伯菌(Klebsiella pneumoniae)外膜蛋白OmpK17基因序列特征及其免疫原性。参照GenBank中肺炎克雷伯菌外膜蛋白OmpK17基因序列(登录号:U52843.1)设计1对特异性引物,应用PCR技术扩增获得了肺炎克雷伯菌榆中分离株(YZ株)OmpK17基因CDS序列,应用相关软件及程序对OmpK17基因核苷酸序列及其推导的氨基酸序列进行生物信息学分析,构建其原核表达载体pET-OmpK17,并在大肠杆菌BL21(DE3)中进行了表达。表达产物纯化后免疫新西兰兔制备多抗血清,应用ELISA和Western blotting分析了重组蛋白的免疫原性。结果显示,肺炎克雷伯菌YZ株外膜蛋白OmpK17基因高度保守,其CDS序列全长513 bp,编码170个氨基酸,与GenBank中其他肺炎克雷伯菌OmpK17基因序列同源性均高于99.6%;OmpK17蛋白分子质量约为18.5 ku,具有较强的亲水性,含有1个信号肽、1个跨膜区和6个抗原决定簇区域,是一种具有桶状三维结构的跨膜蛋白。SDS-PAGE结果显示,OmpK17基因在大肠杆菌中获得表达且表达产物主要以包涵体形式存在。ELISA及Western blotting结果表明,肺炎克雷伯菌OmpK17蛋白具有良好的免疫原性。本研究克隆和表达了肺炎克雷伯菌OmpK17基因及其编码蛋白,并证实该蛋白具有良好的免疫原性,为OmpK17基因的生物学特性研究和肺炎克雷伯菌检测方法的建立奠定了基础,为肺炎克雷伯菌基因工程疫苗的研发提供了理论依据。 相似文献
138.
猪肺炎支原体(Mycoplasma hyopneumoniae,MHP)是猪气喘病的病原。DnaK又称为热休克蛋白Hsp70,具有分子伴侣和免疫的作用。以MHP中国分离株Yin-1为模板,扩增了DnaK基因的全序列,将该序列克隆到pMD18-T载体上并测序。测序结果Yin-1株DnaK基因即Hsp70基因全长1803bp,编码600aa,第631~633位TGA在支原体编码色氨酸而不是作为终止密码子。将该序列与多种致病支原体DnaK基因进行分析比较,发现Yin-1株与232株、J株、7448株等MHP菌株的DNA同源性为99.3%~99.4%,氨基酸同源性为99.2%~99.3%,而与非同种支原体的DNA和氨基酸同源性仅为64.5%~74.4%和59.3%~77%。这表明DnaK基因在种内高度保守,种间差异较大。以pET28a为载体构建重组质粒,原核表达DnaKC末端大小为1kb左右的基因,对表达的蛋白进行纯化后,通过Westernblot检测它的免疫活性。原核表达得到大小为41ku的目的蛋白.经Westernblot证实.纯化蛋白可与MHP阳性猪血清反应,具有免疫活性。 相似文献
139.
Dara Zirofsky Wendy Rekers Cynthia Powell Jennifer Hawley Julia Veir Michael Lappin 《Topics in companion animal medicine》2018,33(2):45-48
Signs of ocular infections like discharge and conjunctivitis occur commonly in cats in shelters and feline herpesvirus 1 (FHV-1), Chlamydia felis, Mycoplasma spp, and feline calicivirus (FCV) are thought to be the most common causes. While molecular assays are available to amplify nucleic acids of each of these agents as single tests or in panels, additional information is needed concerning whether the assay results can be used to predict response to treatment. The objectives of this study were to report results for conventional polymerase chain reaction (PCR) assays that amplify nucleic acids of FHV-1, Mycoplasma spp., C. felis, and FCV from cats with signs of acute ocular and upper respiratory infections in an animal shelter and to determine whether the results are associated with treatment responses to topical administration of cidofovir (anti-FHV-1) or oxytetracycline (anti-Mycoplasma spp. and C. felis). Conjunctival samples were collected from both eyes of 60 cats with ocular signs of disease. Total deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) were extracted from each sample and assayed for DNA of FHV-1, Mycoplasma spp., and C. felis and RNA of FCV by conventional PCR assays. Cats were randomized to be administered either oxytetracycline ointment or cidofovir drops in both eyes and a standardized ocular disease score system was used to determine a total ocular score for each cat prior to treatment on Day 0 and on Day 7. Nucleic acids of one or more agents were amplified from one or both eyes from 39 of 60 cats (65%). FHV-1 DNA (21 cats), Mycoplasma spp. DNA (25 cats) or FCV RNA (2 cats) were amplified most commonly. After treatment for 7 days, 32 of 60 cats (53.3%) were considered improved with 27 of 32 cats (84.4%) having ocular scores of 0 (21 cats) or 1 (6 cats). When the results of the FHV-1 PCR assay were compared to cidofovir treatment responses, the positive and negative predictive values of the assay were shown to be 29.4% and 60%, respectively. When the results of the Mycoplasma spp. PCR assay were compared to oxytetracycline treatment responses, the positive and negative predictive values of the assay were shown to be 40% and 38.5%, respectively. The predictive value of conventional PCR assay results for FHV-1 or Mycoplasma spp. DNA was low, suggesting that performing these tests to formulate a treatment protocol has minimal clinical utility in cats with suspected acute ocular infections. 相似文献
140.
Citrus huanglongbing (HLB), previously called greening, is a serious citrus disease in Asia, eastern and southern Africa. It is caused by Candidatus Liberibacter asiaticus (Las), a phloem-limited, nonculturable bacterium transmitted by the Asian citrus psyllid ( Diaphorina citri ) in Asia. A PCR-based assay was developed for monitoring Las in vector psyllids using a rapid DNA extraction from psyllid bodies and PCR amplification. The entire procedure for Las detection in psyllids can be completed within 5 h. Using this method, Las can be accurately detected in psyllid adults as well as nymphs in different instar stages. The assay is sensitive enough for Las detection in single-psyllid extract from adult, fifth, fourth and third instars. In a transovarial transmission experiment, Las was not detected in eggs or in offspring produced by Las-carrying psyllid females. In a retention test, the Las-carrying psyllids remained Las-positive for 12 weeks after they were moved to common jasmine orange, a Las-immune plant. From these experimental results it was concluded that Las persists in the Asian citrus psyllid vector, but is not transovarially transmitted by the vector. These data help in understanding epidemiological characteristics of Las and psyllids in citrus HLB. 相似文献