木霉菌的几丁质酶与植病生防

Chitinase of Trichoderma spp.and its role in biological control of plant pathogens

木霉菌的几丁质酶是其防治植物真菌性病原菌的主要机制之一,它能降解真菌的细胞壁。木霉菌的几丁质酶具有结构和编码基因多样性。已经纯化的木霉菌几丁质酶有内切和外切几丁质酶,壳二糖酶和N-乙酰-β-D-葡萄糖胺酶。已经克隆的有编码33和42-KDa内切几丁质酶和编码73-KDa的N-乙酰-β-D-葡萄糖胺酶基因。42-KDa内切几丁质酶是目前研究最多的,已经用于转基因植物的培育;对它的表达和调控也有部分了解。

Chitinases secreted by Trichoderma spp.have been addressed as one of the major mechanisms of biocontrol activity,they are responsible for the degradation of fungal cell walls.Trichoderma chitinases are diversified both in structures and in coding genes.Purified chitinase includes endochitinase,exochitinase,chitobiosidase,and NacetylβDglucosaminidase.Genes encoding 33and 42KDa endochitinases and 73KDa NacetylβDglucosaminidase have been cloned.42KDa chitinase is the one of most studied and has been used in transgenic plants,and its expression and regulation are known partially.