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产气荚膜梭菌α毒素保护性抗原基因在大肠杆菌中的高效表达 总被引:15,自引:3,他引:12
对含有产气荚膜梭菌(Clostridiumperfringens)α毒素基因的重组菌株BL21(DE3)(pXETA1)和BL21(DE3)plysS(pXETA1),通过培养性状观察和小鼠接种试验,证明这2株重组菌株均无致病性。随后对这2株重组菌株的表达产物进行了研究,经SDS-PAGE和薄层凝胶扫描分析,IPTG诱导3~4h后的BL21(DE3)(pXETA1)表达的α毒素占菌体总蛋白33.21%,BL21(DE3)plysS(pXETA1)表达的α毒素占菌体总蛋白27.25%,其相对分子质量约37500;经Westernblot分析,表达产物可被α毒素抗血清识别。包涵体粗提物的免疫攻毒试验结果表明,以1倍致死量攻击的免疫小鼠可获得100%(36/36)的保护,以2倍致死量攻击的免疫小鼠可获得94.28%(33/35)的保护,从而说明表达产物具有良好的免疫原性。 相似文献
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选择具有显著抗炎效果的甘草总黄酮为受试化合物,考察其抗产气荚膜梭菌所致鸡坏死性肠炎的效果,为甘草总黄酮在坏死性肠炎的治疗应用提供依据。选择AA^+肉鸡,经口给予产气荚膜梭菌ATCC13124菌悬液建立肉仔鸡坏死性肠炎模型,之后使用甘草总黄酮对造模成功的肉鸡进行治疗,通过剖检考察肉鸡肠道的病变情况、病变评分、日增重及器官指数等指标以评估甘草总黄酮对坏死性肠炎的治疗效果。结果显示,通过经口攻菌成功建立了肉仔鸡坏死性肠炎模型;剖检发现,经甘草总黄酮治疗的模型鸡其肠道病变程度明显缓解,病变损伤评分显著低于感染组,炎性因子含量显著降低;治疗组肉鸡日增质量及器官指数与健康肉鸡差异不显著。结果表明,甘草总黄酮能够缓解产气荚膜梭菌所致坏死性肠炎对肉鸡肠道的损伤,具有作为抗生素替代品治疗坏死性肠炎的潜力。 相似文献
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产气荚膜梭菌(Clostridium perfringens,CP)是重要的食源性病原体之一,可对人类和动物健康造成严重威胁。CP在家禽中主要引起禽坏死性肠炎,严重影响了全球肉鸡贸易与生产。关于禽CP的研究当前主要集中于检测及分型方法、疫苗和耐药性方面。目前禽CP疫苗多处于实验室研发阶段,因此禽CP感染的防治主要依靠抗生素,而抗生素的频繁使用又导致了菌株耐药性问题,防治效果有限。因此,CP耐药性研究以及临床诊断技术完善及疫苗研发推进迫在眉睫。本文简述了CP的病原特点、致病机理及禽间的优势流行分型,梳理了禽CP不同检测方法的优点及分型方法,阐述了禽CP耐药现状以及疫苗研发方向及进展,提出了禽CP感染辅助防治措施,以期为CP感染防控提供参考。 相似文献
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产气荚膜梭菌 (Clostridiumperfringens)的致病作用一般由它所产生的胞外酶或毒素诱导。主要有α -毒素、β -毒素、θ -毒素及其他的一些胞外酶。本文针对产气荚膜梭菌α毒素的组成、结构、理化性质、作用机理及分子遗传等方面的研究进展作了简要综述。 相似文献
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The effect of Eimeria tenella infection on the caecal population of lincomycin-resistant Clostridium perfringens (KGW 851) newly introduced into chickens was studied. Four groups of chickens consisted of: (1) Uninoculated controls; (2) inoculated with C perfringens (KGW 851); (3) inoculated with E tenella; and (4) inoculated with C perfringens (KGW 851) followed by E tenella. Five chickens in each group were necropsied on each of days 0, 3, 5, 7, 10 and 14 after the E tenella inoculation. The mean total C perfringens counts in the caecal contents increased at five days after E tenella inoculation and reached maximum counts at seven days after the inoculation. Also lincomycin-resistant C perfringens readily established itself at approximately one 10th of the total C perfringens population in the presence or absence of E tenella infection. 相似文献
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G Glünder 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1989,36(3):217-225
The flora of the large intestine of 92 grey herons was examined for the frequency of aerobic and microaerobic growing bacteria. Clostridium perfringens, Aeromonas hydrophila, Plesiomonas shigelloides and E. coli were isolated from 55%, 48%, 14% and 35% of the birds, respectively. It could be demonstrated that the findings of these bacteria in the intestinal flora are depending on the age of the birds. The percentage of carriers of Clostridium perfringens, Aeromonas hydrophila and Plesiomonas shigelloides was highest in nestlings younger than 18 days, less high in older nestlings and lowest in adult grey herons. Contrary to those bacteria, E. coli was found more often in the intestinal flora at increasing age of the birds. Salmonella spp. were isolated from 6 birds. Two birds yielded positive for Yersinia enterocolitica and Campylobacter spp., respectively. Other aerobic and microaerobic bacteria play a less significant role as part of the intestinal flora. 相似文献
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产气荚膜梭状芽孢杆菌病的流行与致病机制 总被引:19,自引:2,他引:17
产气荚膜梭状芽孢杆菌是人和动物肠道的正常菌群,亦是条件性致病菌,该菌感染主要由毒素导致的毒血症致病,因此,有针对地选用类毒素预防接种,才能防止本病流行。 相似文献
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We evaluated the ability of hen-egg antibodies (HEA) to reduce intestinal colonization by Clostridium perfringens in broiler chickens. Antibodies against C. perfringens or cholera toxin (negative control) were obtained from the eggs of laying hens hyperimmunized using a C. perfringens bacterin or cholera toxin. Eggs were collected, pooled, and egg antibodies were concentrated by polyethylene-glycol precipitation. An initial experiment was conducted to determine the in vivo activity of the administered antibody along the length of the intestine. Thereafter, two feeding trials were performed to assess the efficacy of feed amended with the egg antibodies in reducing the level of colonization of C. perfringens in challenged birds. Antibody activity declined from proximal to distal regions of the intestine but remained detectable in the cecum. In the first experiment there was no significant reduction in the number of C. perfringens in the birds fed the diet amended with the anti-C. perfringens egg antibody, compared to the birds that received the anti-cholera toxin egg antibody (n = 10), at any of the sampling times. In the second experiment there was a significant decrease in C. perfringens intestinal populations 72 h after treatment (n = 15) as assessed by culture-based enumeration, but there was no decrease as measured by quantitative PCR based on the C. perfringens phospholipase C gene. Intestinal-lesion scores were higher in the birds that received the anti-C. perfringens HEA. Our work suggests that administration of HEA did not reduce the level of C. perfringens intestinal colonization and conversely might exacerbate necrotic enteritis. 相似文献
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