KINETICS OF MANGANESE RECONSTITUTION AND THIOL-GROUP EXPOSITION IN DIALYZED RAT MAMMARY-GLAND ARGINASE

被引：12

作者：

FUENTES, JM ^{[1
]}

CAMPO, ML ^{[1
]}

SOLER, G ^{[1
]}

机构：

[1] UNIV EXTREMADURA,FAC VET,DEPT BIOQUIM,E-10071 CACERES,SPAIN

来源：

INTERNATIONAL JOURNAL OF BIOCHEMISTRY | 1994年 / 26卷 / 05期

关键词：

ARGINASE; RAT MAMMARY GLAND; MANGANESE; SULFHYDRYL GROUP;

D O I：

10.1016/0020-711X(94)90165-1

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：

1. Rat mammary gland arginase is a metallo-enzyme dependent on Mn2+, which can be only partially substituted by Cd2+. 2. Reconstitution of the activity of dialyzed arginase by manganese is a two-phase process; the second phase is independent of the cation concentration, with a half-time recovery (t1/2) of 10.77 min. 3. The apparent K-m for Mn2+ is 280 mu M and 10.5 mu M for enzyme dialyzed for 24 and 72 hr, respectively. 4. Treatment with 5mM EDTA at pH6 totally inhibits enzyme activity, which is reconstituted by Mn2+. 5. Results obtained with iodocetamide treatment suggest the existence of sulphydryl groups accessible only when the enzyme is dialyzed.

引用

页码：653 / 659

页数：7