COENZYME ADOB12 VS ADOB12.- HOMOLYTIC CO-C CLEAVAGE FOLLOWING ELECTRON-TRANSFER - A RATE ENHANCEMENT GREATER-THAN-OR-EQUAL-TO-10(12)

被引：31

作者：

FINKE, RG

MARTIN, BD

机构：

[1] Department of Chemistry, University of Oregon, Eugene, OR

来源：

JOURNAL OF INORGANIC BIOCHEMISTRY | 1990年 / 40卷 / 01期

关键词：

D O I：

10.1016/0162-0134(90)80036-W

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：

Comparison of the 25°C CoC bond homolysis rate constant of adenosyl-cobalamin (coenzyme B12) vs that for electrochemically reduced adenosyl-cobalamin radical anion indicates a rate enhancement of at least 1012±2 upon the addition of one antibonding electron. Even though electrochemical reduction promotes CoC homolysis by virtually the same amount as the 1012±2 enzymic activation seen for adenosylcobalamin, electron-transfer activation of the CoC homolysis in adenosylcobalamin-dependent enzyme reactions is considered unlikely, based on four lines of evidence. © 1990.

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页码：19 / 22

页数：4

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