枯草芽孢杆菌Zl-2抗菌蛋白特性及对小麦赤霉病菌的抑制作用

Characterization and inhibition effects of antifungal protein from Bacillus subtilis Zl-2

为揭示生防菌枯草芽孢杆菌菌株Zl-2产生的抗菌蛋白性质及对小麦赤霉病菌的抑制作用,采用硫酸铵对菌株Zl-2的发酵液进行分级沉淀获得抗菌粗蛋白,然后研究该抗菌蛋白对热、酸碱、紫外光和蛋白酶的稳定性,同时以小麦赤霉病病原菌禾谷镰刀菌(Fusarium graminearum)为靶标菌,对活性蛋白的抗菌作用进行初步研究。结果表明,Zl-2产生的抗菌蛋白具有很好的耐热、耐紫外特性,对酸碱和蛋白酶敏感,抗菌蛋白的抗菌作用主要表现在对禾谷镰刀菌菌丝生长有强烈的抑制作用,并且使菌丝生长的形态畸形、底端膨大、对孢子的萌发也有抑制作用。因此,枯草芽孢杆菌Zl-2的抗菌蛋白具有稳定性好、抗菌能力强的特点,不同于目前已研究的来自枯草芽孢杆菌的抗菌物质,可能为新的抗菌蛋白。

In order to separate a type of antifungal antifungal effects, we use the crude protein of Z1-2 protein from Bacillus subtilis Z1-2, and investigate its to precipitate with ammonium sulfate （ （NH4 ）2SO4 ）. The stability of antagonistic protein under different conditions, such as temperature, pH value, ultraviolet and protease, was investigated to understand the antifungal effects mentioned above. The antifungal activ- ity was measured by Fusarium graminearum as an indicator. The results showed that the antifungal pro- tein exhibited a high stability towards the temperature and ultraviolet, but sensitive to pH value and prote- ase. This Z1-2 protein displayed strong inhibition on the growth of Fusarium graminearum mycelium, which led to mycelium malformation, bottom inflation; and inhibited the spore germination. This researchdiscovered that antifungal protein of Bacillus subtilis ZI-2 showed high stability and strong antifungal abili- ty. Importantly, this protein displayed different characteristics, compared with currently-known metabo- lites obtained from Bacillus subtilis, suggesting that B. subtilis Z1-2 had potential to be a novel antifungal protein.