目的 在包含腺病毒全基因组40 kb的大质粒上快速实现单碱基突变.方法 通过重叠PCR方法扩增出含有突变位点的打靶DNA,将腺病毒大质粒和打靶DNA共同转化入Red高重组率大肠杆菌中,通过菌落PCR联合酶切鉴定的方法,筛选到携带突变位点大质粒的菌株.并将得到的突变大质粒再次转化入质粒高稳定菌株DH10B中,以保持质粒骨架的稳定性.结果 通过该法在腺病毒的9171位点和24410位点连续引入了2个单碱基突变.酶切鉴定了骨架质粒的稳定性,测序结果显示突变位点正确.结论 成功建立了一种快速在40 kb的腺病毒大质粒上实现单碱基突变的技术,阳性突变位点检出率在5%~15%,该法的建立为研究腺病毒的毒理作用提供了技术平台.“,”Objective To construct a highly efficient approach to the introduction of the single-base mutation in a plasmid containing the adenovirus whole genome larger than 40 kb.Methods The target DNA with a mutation site was achieved by over-lapping PCR.The large plasmid with adenovirus genome and target DNA were co-transformed into Escherichia coli strain DY330 carrying a high rate Red recombination system.The positive clone was selected via colony PCR in combination with enzyme identification.The site-mutation large plasmid was transformed into E.coli strain DH10B in which the backbone of the large plasmid remained was stable.Results Two mutations were continuously introduced into the adenovirus genome,the location of which was pos.9171 and pos.24410 respectively.The integrality and stability of the plasmid backbone were verified by enzyme cutting identification.The two mutations on the plasmid were verified by DNA sequencing.Conclusion An efficient approach to the introduction of the single-base mutation in positions 9171 and 24410 from the adenovirus genome which was integrated into a plasmid is successfully established.The positive selection efficiency ranges from 5%to 15%.The construction of the approach will facilitate the study of adenovirus infection mechanism.