海洋假单胞菌GY-1菌株的抗菌作用及其胞外抗菌蛋白的分离纯化

采用对峙培养法和牛津杯法测定海洋假单胞杆菌(Pseudomonas) GY-1菌株和发酵液的抑菌作用。结果表明：GY-1菌株和发酵液对小麦根腐病菌(Bipolaris sorokiniana)、禾谷镰刀病菌(Fusarium graminearum)、菠菜早疫病菌(Alternaria solania)、斑点落叶病菌(Alternaria alternata)、油菜菌核病菌(Sclerotinia sclerotiorum)和小麦叶枯病菌(Alternaria tenuis Nees)等植物病原真菌有较强的抑制作用。发酵液采用硫酸铵分级沉淀、DEAE Sepharose Fast Flow柱层析、Sephadex G-75凝胶层析，以小麦根腐病菌为指示菌进行活性追踪和SDS-PAGE电泳纯度跟踪检测，纯化出一种对小麦根腐病菌具有明显抗菌作用的抗菌蛋白，其分子质量约为70.9kD。

Antifungal Activity of Marine Pseudomonas GY-1 and Purification of the Antifungal Protein

In the present study, agar-well diffusion method and Oxford Cup method were used to detect the antimicrobial activities of marine Pseudomonas GY-1 strain. The results showed that GY-1 strain and its fermentation broth had relatively strong inhibition activity against a variety of phytopathogenic fungi, including Bipolaris sorokiniana, Fusarium graminearum, Alternaria solania, Alternaria alternate, Sclerotinia sclerotiorum and Alternaria tenuis Nees. Further study had successfully purified a protein from Pseudomonas GY-1 by ammonium sulfate fractional precipitation, DEAE sepharose fast flow ion exchange chromatography and Sephadex G-75 filtration chromatography. This protein showed obvious inhibition activity against B. sorokiniana. SDS-PAGE analysis revealed that the molecular weight of the protein was about 70.9 kD.