棉花黄、枯萎病拮抗菌的筛选及抗菌蛋白B110-a的初步测定

从分离自中药上的307株芽孢杆菌中,筛选到3株对棉花黄、枯萎病菌均有强烈抑制作用的菌株,B₁₁₀、B₁₈₄和B₂₁₆,其中B₁₁₀拮抗作用尤为显著。B₁₁₀分离自中药白豆蔻,根据其形态特征和生理生化特征初步鉴定为枯草芽孢杆菌,其蛋白粗提液经Sephadex^TMG-75后得到两个峰,其中峰a有较强抑菌活性,命名为B_110-a,峰b基本无活性;SDS-PAGE分析结果显示B₁₁₀-a主要由两种蛋白组成,含量较高的分子量为50kD,含量较低的分子量为29kD。

Isolation of antagonistic Bacillus and purification of antifungal protein B110-a

Three antifungal strains of Bacillus, namely B110, B184 and B216, which were isolated from Chinese traditional medicines, strongly inhibited the spreading of cotton Verticillium wilt disease and Fusarium oxysporura f. sp. vasinfectum. Bl10 was identified as Bacillus subtilis by its cell morphological, physiological and biochemical characters. One component of the antifungal proteins from B110 was separated by gel filtration through Sephadex^TM G -75 column, which was named as B110-a. SDS-PAGE showed that B110-a included two protein gradients, the molecular weight of which was 50kD and 29kD, respectively.