【摘要】 为了研究A型产气荚膜梭菌α毒素(PLC)的致病性,采用PCR扩增编码产气荚膜梭菌α毒素去除信号肽的plc基因片段,构建重组质粒pGEX-plc,经IPTG诱导表达获得重组蛋白PLC。对纯化鉴定后的PLC蛋白进行细胞毒性试验,结果显示,感染后第4小时Hela细胞开始出现病变,并随时间延长而逐渐严重,说明α毒素对Hela细胞有毒性作用。进一步建立小鼠病理模型,重组PLC蛋白接种组与阳性细菌感染组的病理变化显示,小鼠发病迅速,腹部膨大,肠道臌气明显;组织学观察结果显示,被感染小鼠内脏器官出现不同程度的病理变化,以小肠各段尤为明显,表现为肠黏膜损伤、绒毛脱落等。上述结果为A型产气荚膜梭菌致病机制的研究奠定了基础。更多还原

【Abstract】 In order to study the pathogenicity of alpha toxin(phospholipase C,PLC)of Clostridium perfringens type A,aplc gene encoding C.perfringens alpha toxin excluding signal peptide was amplified by PCR and a recombinant expression vector pGEX-plc was constructed.The recombinant protein PLC was expressed induced with IPTG.The in vitro cytotoxicity test of the identified and purified protein PLC showed that Hela cells began to appear pathologic lesions at hour 4post-infection and became serious with the time extending,indicatingαtoxin has virulent effect on Hela cells.Furthermore,a mouse disease model was established.The pathological changes showed fast onset in the recombinant PLC protein injected group and positive bacterial infection group,including abdominal swelling and intestinal gas swollen significantly.Histological observation showed that internal organs of the injected and infected mice with different degrees of pathological changes,especially in small intestine,which showed intestinal mucosal damage,villus loss.The above-mentioned results laid the foundation for study on the pathogenic mechanism of C.perfringens type A.更多还原