Isolation and Purification of Antifungal Protein from Burkholderia pyrrocinia JK-SH007

Abstract:

A preliminary study on the antagonistic protein produced by Burkholderia pyrrocinia JK-SH007 was carried out. The results showed it was stable to heat, not sensitived to proteinase K and partially sensitive to alkali. Cell culture was obtained after centrifuging and filtering (0.22 μm) of ferment liquid of B. pyrrocinia JK-SH007 by shake-flask fermentation. The crude proteins were obtained by fractionation with (NH4)2SO4 (20%-60%). Active proteins(A-Ⅱ-2) were obtained after purification of the crude proteins by 3.5 kD dialysis bag dialysis, cold acetone precipitation (-20°C), Sephadex G-50, DEAE-Sephadex A-25 aion-exchange column chromatography. A-Ⅱ-2 were shown three bands by SDS-polyacrylamide gel electrophoresis (SDS-PAGE). The proteins showed good inhibition activity to three pathogens Cytospora chrysosperma, Phomopsis macrospore and Fusicoccum aesculi which caused poplar canker.

Key words:Poplar canker, Burkholderia pyrrocinia, Antifungal protein, Isolation and purification, Antagonistic bacteria