Collis C M, Grammaticopoulos G, Briton J, Stokes H W, Hall R M
CSIRO Division of Biomolecular Engineering, Sydney Laboratory, North Ryde, New South Wales Australia.
Mol Microbiol. 1993 Jul;9(1):41-52. doi: 10.1111/j.1365-2958.1993.tb01667.x.
Site-specific insertion of gene cassettes into the insert region of integrons has been demonstrated. Insertion was only observed if the integron DNA integrase was expressed in the recipient cell and if the cassette DNA was ligated prior to transformation. The essential ligation products were resistant to treatment with exonuclease III, indicating that they were closed circular molecules. Insertion of cassettes into integron fragments containing either no insert (one recombination site), or one gene cassette (two recombination sites), was demonstrated. In the latter case, insertion occurred predominantly at the core site located 5' to the resident cassette, which corresponds to the only site available when no insert is present in the recipient. When DNA molecules including two gene cassettes were used, insertion of only one of the gene cassettes was generally observed, suggesting that resolution of the circular molecule to generate two independent circular cassettes occurred more rapidly than insertion into the recipient integron.
已证实基因盒可位点特异性插入整合子的插入区域。仅当整合子DNA整合酶在受体细胞中表达且盒式DNA在转化前进行连接时，才会观察到插入现象。必需的连接产物对外切核酸酶III处理具有抗性，表明它们是闭环分子。已证实基因盒可插入不含插入片段（一个重组位点）或一个基因盒（两个重组位点）的整合子片段中。在后一种情况下，插入主要发生在位于常驻盒式结构5'端的核心位点，该位点与受体中不存在插入片段时唯一可用的位点相对应。当使用包含两个基因盒的DNA分子时，通常仅观察到其中一个基因盒插入，这表明环状分子生成两个独立环状盒式结构的拆分比插入受体整合子的速度更快。
