甲壳动物几丁质酶基因的结构与功能

Structure and function of chitinase gene in crustaceans

综述几丁质酶的分类,并以50条甲壳动物几丁质酶为例,验证氨基酸同源性的分类方式可以将甲壳动物几丁质酶细分为Group 1~Group 7。重点介绍甲壳动物几丁质酶的结构和功能,结构方面主要从Group 1~Group 7几丁质酶氨基酸序列的保守基序(Motif)组成特点和Group 1~Group 7几丁质酶结构域组成特点进行阐述,并以三疣梭子蟹(Portunus trituberculatus)几丁质酶为例结合解析过的几丁质酶结构,预测甲壳动物几丁质酶三维空间结构特点;功能方面几丁质酶主要参与几丁质食物的消化、蜕皮时旧壳的消化以及通过降解病原体几丁质外壳来对抗病原,发挥免疫防御的功能。

The classification of chitinases in 50 crustaceans was reviewed and it was verified that chitinases in crustaceans could be subdivided into group 1-group 7 according to the classification of amino acid homology.The structure and the function of chitinase in crustaceans were focused in this review.In terms of structure,the characterization of conserved motifs based on amino acid sequence,as well as the composition profile of several domains of group 1-group 7 chitinases were discussed.Then,the three-dimensional structure of one of chitinases from P.trituberculatus,which was considered as a symbol of the crustacean chitinase,was predicted.The functions of crustacean chitinase were further stated and it generally participated in the digestion of chitinous food,in the digestion of old shells during molting,as well as degrading the chitinous cell wall of pathogen to exert its function on immune defense.