重组双基因鸭源大肠杆菌菌蜕的制备

Generation of bacterial ghost fromEscherichia coli in ducklings by expression of Lysis gene E and Staphylococcal nuclease A gene

目的利用裂解E基因和葡萄球菌核酸酶A(SN)基因的表达,制备鸭源大肠杆菌(E.coli)菌蜕。方法通过将带有裂解E基因和葡萄球菌核酸酶A(SN)基因的质粒pET29a-E-S转化至鸭源E.coli O_(92)中,对E.coli O_(92)(pET29a-E-S)进行诱导,每隔30min检测菌液的OD_(600)值,并检测培养液中所含DNA。结果通过诱导,E.coli O_(92)(pET29a-E-S)OD_(600)值在诱导90min后开始持续下降,180min时开始趋于平稳,到360min溶菌效率达99.999%。并且葡萄球菌核酸酶把DNA降解为50~400bp的小片断。结论通过裂解E基因和SN基因表达,成功制备了E.coli O_(92)菌蜕,本实验为进一步研究该菌蜕疫苗奠定了基础。

We generated bacterial ghost from Escherichia coli in ducklings by expression of Lysis gene E and Staphylococcal nuclease A gene. Plasmid pET29a-E-S consisting of E gene and Staphylococcal nuclease A gene was transferred into E.coli O92 from ducklings. E.coli O92（pET29a-E-S） was induced to lyse and the OD600 value of culture media was measured every 30 min during the induction, and DNA in medium were detected. The result showed the OD600 value of E.coli O92（pET29a-E-S） began to decline after 90 min of induction, after 180 min of induction, the OD600 value decline speed became slowly, and after 360 min of induction, the rate of genetic inactivation was at 99.999%. DNA in medium was degraded into small fragments （50 bp-400 bp） by Staphylococcus nuclease A. The E.coli O92 ghost was generated successfully by expression of Lysis E gene and Staphylococcal nuclease A gene, which laid a foundation on the study of bacterial ghost vaccine against E.coli O92 infection.