水稻内生枯草芽孢杆菌G87抗菌蛋白的分离纯化及理化特性

Isolation, purification and characterization of antifungal protein from rice endophytic bacterim Bacillus subtilis G87

摘要:

摘要：【目的】为得到枯草芽孢杆菌（Bacillus subtilis）G87的抗菌蛋白，明确其蛋白理化特性。【方法】采用硫酸铵沉淀和柱层析法进行分离纯化。【结果】获得单一抗菌活性蛋白（峰6-2-1），此抗菌蛋白分子量为50.8 kDa，等电点为5.90。经初步分析，抗菌蛋白不含脂，而含有少量（0.62%）糖；其蛋白部分具有脯氨酸或羟脯氨酸，但不含芳香族氨基酸。抗菌蛋白在高温（≥60℃）和较碱（pH>8）环境下活性明显下降，但较抗紫外线、氯仿和胰蛋白酶、蛋白酶K、胃蛋白酶。【结论】枯草芽孢杆菌G87的抗菌蛋白为不含芳烃的糖蛋白，对高温和碱性条件敏感，而对蛋白酶类和紫外线等不敏感。

Abstract:

Abstract: [Objective] In order to obtain the antagonistic protein of Bacillus subtilis G87 and definitude its characterization. [Methods] Methods of ammonium sulfate precipitating and column chromatography analyzing were used to isolate and purify the protein. [Results] A purified protein (peak 6-2-1) was obtained which molecular weight was 50.8kD by SDS-PAGE and isoelectric point was 5.90 by IEF-PAGE. The antifungal protein contained 0.62% saccharide and some proline or hydroxyproline, but no lipid and aromatic amino acid. The inhibitory activity of the antifungal protein would decreased distinctly at the higher temperature (≥60℃) and in the condition of alkalinity (pH>8), but tolerant to ultraviolet radiation, chloroform, trypsin, proteinase K and pepsin. [Conclusion] Antifungal protein of Bacillus subtilis G87 was a kind of glycoprotein without aromatic hydrocarbon. It was sensitive to higher temperature and tight alkalinity but not to proteinase analog and ultraviolet radiation et al.