【摘要】 通过比较饲喂Cry2Ad诱导的抗Cry2Ad毒素品系和敏感品系小菜蛾抗菌肽的含量和抑菌活性,结果显示,抗Cry2Ad小菜蛾被喂食Cry2Ad毒素后,体内抗菌肽含量显著增高,抑菌活性更强。说明小菜蛾抗菌肽与小菜蛾对Cry2Ad毒素的抗性有一定的相关性。通过SDS-PAGE电泳检验抗菌肽分子量,得到抗Cry2Ad毒素小菜蛾抗菌肽有一分子量约为7.8 KDa特别条带,采用截留量10 KDa的超滤管和阴、阳离子交换柱层析对抗Cry2Ad小菜蛾抗菌肽进行分离、纯化,得到具有抑菌活性的抗菌肽。更多还原

【Abstract】 The content and bacteriostatic activity of antimicrobial peptide were compared between the Cry2 Ad-resistant strain and susceptible strain of Plutella xylostella( L.) fed with Cry2 Ad. The results showed that the content and bacteriostatic activity of antimicrobial peptide were more higher and stronger after the Cry2 Ad-resistant P. xylostella were fed with Cry2 Ad. This indicated that the antimicrobial peptide content in P. xylostella was centainly associated with the resistance of P. xylostella against Cry2 Ad toxin. The molecular weight of antimicrobial peptide was tested using SDS-PAGE electrophoresis,and a special band with molecular weight of approximately 7.8 KDa was detected in the antimicrobial peptide of Cry2 Ad-resistant P. xylostella. An ultrafilter with the cut-off molecular weight of 10 k Da and anion exchange chromatography were used for segregation and purification of the antimicrobial peptide of Cry2 Adresistant P. xylostella,thus the antibacterial peptide composition with bacteriostatic activity was obtained. The study on the characteristics of antimicrobial peptide in Cry2 Ad-resistant strain of P. xylostella provided theoretical basis for investigating the resistance mechanism of P. xylostella to Cry2 Ad toxin in terms of antimicrobial peptide.更多还原