粉纹夜蛾离体细胞抗菌肽的抗菌谱测定

The Antimicrobial Activity Spectrum of Antibacterial Peptide from Induced Trichoplusia ni Cell Line

用热灭活的大肠杆菌DH5α诱导粉纹夜蛾 (Trichoplusiani)离体细胞产生抗菌肽 ,用三氯乙酸沉淀法提取出该活性物质 ,采用琼脂糖孔穴扩散法和生长抑制测定法测定其抗菌谱 ,发现该抗菌物质具有较广的抗微生物活性 ,其中特别是对革兰氏阴性菌中的沙门氏菌和大肠杆菌 ,酵母菌中的白色念珠菌 ,植物病源真菌中的花生白绢病菌和小麦赤霉病菌具有较强的抑菌活性 ,从而表明该物质是一种既抗细菌 ,又抗真菌的抗微生物肽。

The cultured Trichoplusia ni cells were induced with heat-killed Escherichia coli strain DH5a and secreted antibacterial peptides into the medium ,these antibacterial peptides were recovered by acid precipitation. By use of agarose diffusion assay and growth inhibition assay, the antimicrobial activity spectrum of the antibacterial peptide was defined. Results show that this antibacterial peptide has broad inhibitory activity against bacteria,fungi and yeast,especially, it has strong inhibitory activity against G- bacteria:Salmonella derby and Escherichia coli ; yeast:Candida.albicans; fungi:Fusarium graminearum Schwabe and Sclerotium rolfsii Saccardo.Therefore,we can conclude that it is a kind of antimicrobial peptide.