Husain I, Chaney S G, Sancar A
J Bacteriol. 1985 Sep;163(3):817-23. doi: 10.1128/jb.163.3.817-823.1985.
cis-Platinum compounds, which are used in cancer chemotherapy, are thought to exert their effect by damaging DNA. It is known that this damage is partially repaired in Escherichia coli. Using cis-Pt-treated pBR322 DNA as a probe, we investigated the role of nucleotide excision repair in the removal of Pt-DNA adducts. We found that the nucleotide excision pathway was the major mechanism for repairing Pt adducts in transforming plasmid DNA but that a recA-dependent pathway also contributed to plasmid survival. When cis-Pt-damaged pBR322 was treated with the purified nucleotide excision enzyme ABC excinuclease in vitro, a fraction of the adducts was removed by the enzyme; this removal resulted in a corresponding increase in transformation efficiency.
用于癌症化疗的顺铂化合物被认为是通过损伤DNA发挥其作用的。已知这种损伤在大肠杆菌中会得到部分修复。我们以经顺铂处理的pBR322 DNA为探针,研究了核苷酸切除修复在去除铂-DNA加合物中的作用。我们发现,核苷酸切除途径是修复转化质粒DNA中铂加合物的主要机制,但一种依赖recA的途径也有助于质粒存活。当体外使用纯化的核苷酸切除酶ABC核酸内切酶处理经顺铂损伤的pBR322时,一部分加合物被该酶去除;这种去除导致转化效率相应提高。