Structure of 1-aminocyclopropane-1-carboxylate synthase, a key enzyme in the biosynthesis of the plant hormone ethylene |
| |
Authors: | Capitani G Hohenester E Feng L Storici P Kirsch J F Jansonius J N |
| |
Institution: | Structural Biology Division Biozentrum, University of Basel, Basel, CH-4056, Switzerland. capitani@biocfebs.unizh.ch |
| |
Abstract: | The 2.4 A crystal structure of the vitamin B6-dependent enzyme 1-aminocyclopropane-1-carboxylate (ACC) synthase is described. This enzyme catalyses the committed step in the biosynthesis of ethylene, a plant hormone that is responsible for the initiation of fruit ripening and for regulating many other developmental processes. ACC synthase has 15 % sequence identity with the well-studied aspartate aminotransferase, and a completely different catalytic activity yet the overall folds and the active sites are very similar. The new structure together with available biochemical data enables a comparative mechanistic analysis that largely explains the catalytic roles of the conserved and non-conserved active site residues. An external aldimine reaction intermediate (external aldimine with ACC, i.e. with the product) has been modeled. The new structure provides a basis for the rational design of inhibitors with broad agricultural applications. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|