【摘要】 枯萎菌拮抗蜡状芽孢杆菌BC98-I分泌产生的抗真菌物质经粗提、Sephadex G100和DEAE52柱层析分离纯化后,得到了抗菌馏分P1D4。该馏分达到了电泳纯,SDS-PAGE电泳检测其分子量约为3.5kD,等电点为4.65。又经MALDI-TOF质谱检测,该馏分为精确分子量小于或等于1531.71D的多肽。氨基酸组成分析结果表明:馏分P1D4由Asp、Glu、Ser等12种氨基酸组成,富含酸性和极性氨基酸。结合以往研究结果,目标产物热稳定性好,对胰蛋白酶和蛋白酶K有良好耐受性,初步认为属低分子量的环状多肽。更多还原

【Abstract】 Bacillus cereus strain BC98-I is an antagonist that strongly inhibit pathogens causing vegetable,melon and flower wilt diseases.After acid precipitation,methanol and ethyl ether extraction,Sephadex G100 and DEAE 52 column chromatography,the antifungal fraction was purified and named as P1D4.Molecular weight of P1D4 was 3.5 kD detected by SDS-PAGE and PI value is 4.65 by PAGE-IEF respectively.The accurate molecular weight of P1D4 was equal or small than 1 531.71D as determined by MALDI-TOF mass spectrometry.The amino acid composition of peptide was analyzed and results showed that the purified fra-ction was composed of 12 amino acids of Asp,Glu,Ser,etc.Earlier experiments showed that the peptide was possessed of highly stability against ultraviolet radiation,heat,trypsin and proteinase K.Based on the results,it was suggested that this antifungal material was a cyclic peptide.更多还原