基因工程改良淀粉品质

Manipunation of Starch Quality via Genetic Engineering

淀粉对人类生活十分重要，它不仅是人们的能量和营养来源，而且还是重要的工业原材料。对于淀粉合成过程及淀粉的加工、使用一直是淀粉研究的重点内容。淀粉的合成在最后阶段涉及到３个关键性的酶是：ＡＤＰＧ焦磷酸化酶、淀粉合成酶以及淀粉分支酶。它们分别催化ＡＤＰ－葡萄糖的形成、葡聚糖链的延伸以及分支链的形成。另外淀粉去分支酶对淀粉最终结构的形成也起到重要作用。本文将介绍上述４个酶近年来的生物化学和分子生物学研究进展，并在此基础上讨论利用基因工程改良淀粉品质的可能途径。

Starch is both the major component of yield in the world's main crop plants and an important raw material for many industrial process.The last three committed steps in the pathway of starch biosynthesis are catalyzed by three enzymes,ADPG phosphorylase(AGPP),starch synthase and starch branching enzymes.Recent observations suggest that starch-debranching enzymes also play essential role in amylopectin biosynthesis.Based on the recent advances in the biochemistry and molecular biology study of starch biosynthesis enzymes,manipulation of starch quality by gene engineering is discussed.