A novel endonuclease mechanism directly visualized for I-Ppol

被引：103

作者：

Galburt, EA

Chevalier, B

Tang, WL

Jurica, MS

Flick, KE

Monnat, RJ

Stoddard, BL

机构：

[1] Univ Washington, Fred Hutchinson Canc Res Ctr, Seattle, WA 98109 USA

[2] Univ Washington, Grad Program Biomol Struct & Design, Seattle, WA 98109 USA

[3] Univ Washington, Dept Pathol, Seattle, WA 98195 USA

来源：

NATURE STRUCTURAL BIOLOGY | 1999年 / 6卷 / 12期

关键词：

D O I：

10.1038/70027

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

A novel mechanism of DNA endonucleolytic cleavage has been visualized for the homing endonuclease I-PpoI by trapping the uncleaved enzyme-substrate complex and comparing it to the previously visualized product complex,This enzyme employs a unique single metal mechanism, A magnesium ion is coordinated by an asparagine residue and two DNA oxygen atoms and stabilizes the phosphoanion transition state and the 3'oxygen having group. A hydrolytic water molecule is activated by a histidine residue for an in-line attack on the scissile phosphate. A strained enzyme-substrate-metal complex is formed before mechanism directly cleavage, then relaxed during the reaction.

引用

页码：1096 / 1099

页数：4

共 29 条

[1] Novel site-specific DNA endonucleases [J].