S-Methylmethionine is both a substrate and an inactivator of 1-aminocyclopropane-1-carboxylate synthase

被引：18

作者：

Ko, S ^{[1
]}

Eliot, AC ^{[1
]}

Kirsch, JF ^{[1
]}

机构：

[1] Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA

来源：

ARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS | 2004年 / 421卷 / 01期

关键词：

1-aminocyclopropane-1-carboxylate synthase; ACC; S-methylmethionine; pyridoxal phosphate; ethylene biosynthesis; vinylglycine;

D O I：

10.1016/j.abb.2003.10.017

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：

S-methyl-L-methionine (SMM) is ubiquitous in the tissues of flowering plants, but its precise function remains unknown. It is both a substrate and an inhibitor of the pyridoxal 5-phosphate-dependent enzyme 1-aminocyclopropane-1-carboxylate (ACC) synthase, due to its structural similarity to the natural substrate of this enzyme, S-adenosyl-L-methionine. In the reaction with ACC synthase, SMM can either be transaminated to yield 4-dimethylsulfonium-2-oxobutyrate; converted to alpha-ketobutyrate, ammonia, and dimethylsulfide, or inactivate the enzyme covalently after elimination of dimethyl sulfide. These results suggest a previously unrecognized role for SMM in the regulation of ACC synthase activity in plants. (C) 2003 Elsevier Inc. All rights reserved.

引用

页码：85 / 90

页数：6

共 12 条

[1]

Abeles FB., 1992, ETHYLENE PLANT BIOL

[2] S-methylmethionine plays a major role in phloem sulfur transport and is synthesized by a novel type of methyltransferase [J].