Purification, characterization, and heterologous expression of an antifungal protein from the endophytic Bacillus subtilis strain Em7 and its activity against Sclerotinia sclerotiorum
An antifungal protein exhibiting a high activity against Sclerotinia sclerotiorum in vivo was purified by ammonium sulfate precipitation, hydrophobic chromatography, and gel filtration chromatography from the culture filtrate of the endophytic Bacillus subtilis strain Em7. The protein was characterized as a β-1,3-1,4-glucanase according to amino acid analysis, and showed excellent properties in thermal stability and acid resistance. At the same time, the antifungal protein was cloned and heterologously expressed in Escherichia coli BL21.