摘要
目的研究出血性大肠埃希菌的vero细胞毒素。方法通过超声破碎,硫酸铵沉淀及两次离子交换层析,再经过凝胶过滤,最终从大肠埃希菌O157∶H7 882364菌株获得了一种新的vero细胞毒素。对此毒素进行细胞毒性测定和分子量及等电点的测定,并对毒素的N端15个氨基酸序列进行了检测。结果用凝较过滤层析测定纯化的vero细胞毒素分子量为43KD,等电点为3.8,蛋白N端15个氨基酸序列为SFELPALPYAKDALA,其对vero细胞的CD50为4bg。结论这种毒素与VT1毒素和VT2毒素明显不同,因此初步确定为新毒素,称之为VT3。通过实验将推动我国对出血性大肠埃希菌O157∶H7的致病性研究和对VT类毒素和抗毒素的进一步研制和应用。
Objective To research the verocytotoxin of Enterohemorrhagic E. coli （EHEC）. Methods Obtained a new kind of verocytotoxin from EHEC O157 ： H7 strain 882364 called VT. The VT3 was purified from cell lysates. The steps included （NH4）2SO4 precipitation and anion exchange chromatography and gel filtration chromatography. Results The molecular weight of VT3 detected by gel filtrationis 43 KD and the PI was 3.8, N-terminal of protein sequence was SFELPALPYAKDALA. The CD50 of VT3 was 4 pg. Conclusions The VT3 appeared to be similar immunogenicity with VT1. Characteristic analysis of the pure toxin showed VT3 was different from VT1 and VT2. This research improved the research and application of VT antitoxin and toxoid in our country.
出处
《中国微生态学杂志》
CAS
CSCD
2006年第5期343-345,347,共4页
Chinese Journal of Microecology
