λpL/pR-cI857温控系统的改造及其对大肠杆菌菌蜕制备的影响  

Mutation of λpL/pR-cI857 system for production of bacterial ghost in Escherichia coli

作　　者：董洪亮[1,2] 韩先干[2] 白灏[2] 何亮[2] 刘蕾[2] 刘瑞[2] 柴同杰[1] 丁铲[2] 刘海文[2] 于圣青[2] 

机构地区：[1]山东农业大学动物科技学院,山东泰安271000 [2]中国农业科学院上海兽医研究所,上海200241

出　　处：《生物工程学报》2012年第12期1423-1430,共8页Chinese Journal of Biotechnology

基　　金：国家自然科学基金(Nos.31001078;31072161;30871851)资助~~

摘　　要：菌蜕是革兰氏阴性菌在噬菌体Phix174的溶菌基因E的作用下形成的细菌空壳,通常由λpL/pR-cI857温控系统通过调控E基因的表达制备。通过重叠PCR技术,将λpL/pR-cI857温控系统中λpR启动子的第2个操纵基因(OR2)的第9位碱基由T突变为C(T→C)。溶菌试验结果表明,突变后的λpL/pR-cI857系统在37℃时仍能稳定抑制基因E的表达,对大肠杆菌的溶菌率为99.9%。通过对λpR启动子的改造,扩大了λpL/pR-cI857温控系统的温度调控范围,为菌蜕疫苗的研制提供了参考。Bacterial ghost is intact envelope of Gram-negative bacteria, which is produced by the function of the lysis gene E from bacteriophage PhiX174. The expression of the lysis gene E is usually controlled by the thermosensitive λpL/pR-cI857 promoter. In this study, we described a mutation （T→C） at the ninth nucleotide of the OR2 in the kpR promoter of theλpL/pR-cI857 system by overlap PCR. The bacteriolytic assay showed that the mutation in the λpL/pR-cI857 system enhanced the temperature of repressing the expression of gene E up to 37 ℃. The lysis efficiency of altered λpR promoter in Escherichia coli DHS5a and avian pathogenic E. coli DE17 was up to 99.9%. The expanded range of temperature will benefit for the production of bacterial ghost.

关 键 词：大肠杆菌 菌蜕 重叠PCR 突变 

分 类 号：Q93[生物学—微生物学]