神经毒素原性酪酸梭菌与E型肉毒梭菌毒素的精制及特性比较

Purification and Characterization of Toxins of Neurotoxigenic Clostridium Butyricum and Clostridium Botulinum Type E

对首次自Ｅ型肉毒中毒食品中分离到的一株神经毒素原性酪酸梭菌（ＬＣＬ１５５）所产生的神经毒素，同Ｅ型肉毒梭菌（Ｅ１５３）所产生的神经毒素进行了精制及特性比较，发现（１）两菌神经毒素的分子量，Ｎａｔｉｖｅ－ＰＡＧＥ测试均为３２０ｋＤａ；ＳＤＳ－ＰＡＧＥ测试则均为１４７ｋＤａ，非毒性非血凝素部分均为１２８ｋＤａ；用胰蛋白酶激活神经毒素后发现两菌神经毒素均由分子量为１０３ｋＤａ的Ｈ链和４８ｋＤａ的Ｌ链组成。（２）两菌神经毒素柱层析图像基本一致，但在菌体毒素提取效果及精制效果诸方面，分离的酪酸梭菌却都较差。（３）胰蛋白酶激活试验表明：两菌神经毒素达到最大毒力所需激活时间不等。在相同温度下，分离的酪酸梭菌毒素只需５ｍｉｎ，而Ｅ型肉毒梭菌毒素却需３０ｍｉｎ，提示两菌神经毒素激活动力学上存在差异。（４）琼脂双扩散试验结果表明两菌神经毒素的抗原性是一致的，没有发现沉淀线呈交叉或部分交叉现象。

Purification and characterization of toxin produced by neurotoxigenic Clostridium butyricum (strain LCL155) primarily isolated from foodborne botulism were compared with that of toxin produced by Clostridium botulinum type E (Strain E153).Through experiments we found (1)In Native PAGE, both neurotoxins were the same position of 320kDa;SDS-PAGE showed that molecular weight of neurotoxins of both C.butyricum and C.botulinum type E were 147 kDa which,when activated with trypsin,were composed of one H subunit of molecular weight of 103kDa and one L subunit of 48kDa.The nontoxinnonhemagglutinin parts of both were 128kDa.(4)The chromatography figure for purified neurotoxin of the two strains were almost the same,but the isolated strain LCL155 was poorer than strain E153 in effectiveness of toxin purification.(5)When treated with trypsin,C.butyricum strain LCL155 neurotoxin could achieve maximum toxicity in 5 min incubation,whereas C.botulinum strain E153 neurotoxin,in 30 min incubation at a same temperature.Which suggested the existence of difference in kinetics of neurotoxin activation.(6)Immuno-diffusion test indicated that two neurotoxins were serologically similar. 