内生菌BS-2菌株的抗菌蛋白及其防病作用

 BS-2菌株为一株能在多种植物体内定殖,对多种植物炭疽病具有良好防治效果,并对植物生长具有良好促进作用的枯草芽孢杆菌,其BPY培养液经30%~70%硫酸铵盐析、高温(100℃)处理后,以SDS-PAGE、MALDI-TOF检测,该菌株分泌的抗菌蛋白为分子量 ≤ 2884.39 D的多肽;该抗菌多肽对热稳定并抗紫外线照射,对植物炭疽病菌和番茄青枯病菌等多种植物病原真菌和细菌有强烈的抑制作用,并对辣椒果炭疽病具有69.79%(9 d后)的防病效果;抑制病菌生长,引起菌丝(或芽管)细胞消融,导致菌丝畸形以及抑制病菌分生孢子的产生和萌发等可能是该抗菌多肽主要的防病机制。

Antifungal protein from endophytic bacteria BS-2 and its control effect against anthracnose (Colletotrichum gloeosporioides)

Bacillus subtilis BS-2, an endophytic bacterium isolated from capsicum leaf, was found to be able to colonize in many kinds of plants, suppress diseases, such as anthracnose, and promote plant growth. The antifungal compound obtained through ammonium sulfate precipitation was primarily identified as a polypeptide (MW ≤ 2884.39 D)by SDS-PAGE and MALDI-TOF. This antifungal polypeptide of the nature of thermostable and UV-tolerant showed strong inhibitory activity against various plant pathogenic fungi and bacteria, such as Colletotrichum sp. and Ralstonia solanaceance, and had 69.79% control effect (9 d after inoculating the pathogen) against the anthracnose on the capsicum postharvest fruits. Inhibition of pathogen mycelial growth and conidia formation and germination by this antifungal protein was proposed to be the key mechanism in the disease control activity of B. subtilis BS-2.