植物防御素的生物学活性及其应用前景

The biological activities of plant defensins and their application prospects

植物防御素是植物界中一类阳离子型多肽,在结构和功能上,它们与早先发现的哺乳动物和昆虫防御素类似。植物防御素的分子量在5kDa左右,其中含有8个保守的半胱氨酸残基。植物防御素的三维结构呈小球形,包括1个α-螺旋和3个反平行的β-折叠片层结构,8个半胱氨酸可以形成3对或4对二硫键,从而构成了Cys稳定的βαββ结构模序。从植物防御素的结构和体外生物学活性,可以看出植物防御素是一类十分复杂的多肽,它的作用不仅仅局限于植物免疫,而应具有广阔的应用前景。

Plant defensins are cationic peptides in the plant kingdom,they are structurally and and functionally related to defensins that have been previously characterized in mammals and insects. And their molecular mass are nearly 5 kDa,including eight conserved Cys residues. The three-dimensional structure of plant defensins is small and globular. It has one α-helix,three antiparallel β-sheets and three or four disulfide bridges formed by eight Cys residuals,thus is called the Cys stabilizedαβ motif （CSαβ）. Based on the structure and vitro activities of plant defensin,it seems clear that plant defensins are so sophisticated peptides that their effects can not be limited to plant defense,and it has a wide field of application with good prospects.