Brandsma J A, de Ruijter M, Visse R, van Meerten D, van der Kaaden M, Moggs J G, van de Putte P
Laboratory of Molecular Genetics, Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, Netherlands.
Mutat Res. 1996 Jan 2;362(1):29-40. doi: 10.1016/0921-8777(95)00028-3.
The toxic effect and the mutagenicity of two differentially repaired site-specific cis-diamminedichloroplatinum(II) (cis-DDP) lesions were investigated. Detailed analysis of the UvrABC-dependent repair of the two lesions in vitro showed a more efficient repair of the cis-Pt.GG adduct compared to that of the cis-Pt.GCG adduct (Visse et al., 1994). Furthermore, previously, a dependency of cis-DDP mutagenesis on UvrA and UvrB, but not on UvrC was found (Brouwer et al., 1988). To possibly relate survival and mutagenesis to repair, plasmids containing the same site-specific cis-DDP lesions as those that were used in the detailed repair studies were transformed into Escherichia coli. The results indicate that both lesions are very efficiently bypassed in vivo. Mutation analysis was performed using a denaturing gradient gel electrophoresis technique, which allows identification of mutations without previous selection. Although the cis-Pt.GG adduct is in vitro more efficiently repaired than the cis-Pt.GCG adduct, it appeared to be more mutagenic. We present a model in which this result is related to the previously observed dependency of the mutagenicity of cis-DDP lesions on the Uvr A and B proteins.
研究了两种差异修复的位点特异性顺二氨二氯铂（II）（顺铂）损伤的毒性作用和致突变性。对这两种损伤在体外的UvrABC依赖性修复进行详细分析表明，与顺铂.GCG加合物相比，顺铂.GG加合物的修复效率更高（维斯等人，1994年）。此外，之前发现顺铂诱变依赖于UvrA和UvrB，但不依赖于UvrC（布劳威尔等人，1988年）。为了将存活率和诱变作用与修复联系起来，将含有与详细修复研究中使用的相同位点特异性顺铂损伤的质粒转化到大肠杆菌中。结果表明，这两种损伤在体内都能非常有效地被绕过。使用变性梯度凝胶电泳技术进行突变分析，该技术无需预先筛选就能鉴定突变。虽然顺铂.GG加合物在体外比顺铂.GCG加合物修复效率更高，但它似乎更具致突变性。我们提出了一个模型，该模型将这一结果与之前观察到的顺铂损伤的诱变性对UvrA和B蛋白的依赖性联系起来。
