DNA螺旋中的氧化性胸腺嘧啶二聚体修复

Oxidative thymine dimer repair in the DNA helix.

作者信息

Dandliker P J, Holmlin R E, Barton J K

机构信息

Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.

出版信息

Science. 1997 Mar 7;275(5305):1465-8. doi: 10.1126/science.275.5305.1465.

DOI:10.1126/science.275.5305.1465

PMID:9045609

Abstract

The metallointercalator Rh(phi)2DMB3+ (phi, 9,10-phenanthrenequinone diimine; DMB, 4,4'-dimethyl-2,2'-bipyridine) catalyzed the repair of a thymine dimer incorporated site-specifically in a 16-base pair DNA duplex by means of visible light. This repair could be accomplished with rhodium noncovalently bound to the duplex and at long range (16 to 26 angstroms), with the rhodium intercalator tethered to either end of the duplex assembly. This long-range repair was mediated by the DNA helix. Repair efficiency did not decrease with increasing distance between intercalated rhodium and the thymine dimer, but it diminished with disruption of the intervening pi-stack.

摘要

金属嵌入剂二（菲咯啉）二甲基联吡啶合铑（III）离子[Rh(phi)2DMB3+，其中phi为9,10-菲醌二亚胺，DMB为4,4'-二甲基-2,2'-联吡啶]借助可见光催化修复特定位点掺入16碱基对DNA双链体中的胸腺嘧啶二聚体。铑与双链体非共价结合且在远距离（16至26埃）时即可实现这种修复，铑嵌入剂连接在双链体组装体的任一端。这种远距离修复由DNA螺旋介导。修复效率不会随嵌入铑与胸腺嘧啶二聚体之间距离的增加而降低，但会因中间π堆积的破坏而降低。