柞蚕抗菌肽对柑桔黄龙病及溃疡病病原菌的杀菌作用

首次报道柞蚕（Ａｎｔｈｅｒａｅａｐｅｒｎｙｉ）抗菌肽对柑桔黄龙病病原类细菌（ＢａｃｔｅｒｉａｌｌｉｋｅＯｒｇａｎｉｓｍ，ＢＬＯ）及溃疡病黄单胞菌（ＸａｎｔｈｏｍｏｎａｓｃａｍｐｅｓｔｒｉｓＰＶｃｉｔｒｉＤｙｅ）的杀菌作用，分别在平板培养基上用孔穴法注入５—１０μｌ免疫血淋巴，则出现明显的抑菌圈。用纯化的抗菌肽１０μｇ／ｍｌ处理ＢＬＯ及Ｘ．ｃｉｔｒｉ２０─６０ｍｉｎ，用电镜及激光共焦扫描显微镜观察到病原菌细胞膜的损坏、内容物泄出乃至死亡的过程，对抗菌肽的杀菌机理进行了讨论。

THE BACTERICIDAL EFFECT OF ANTIBACTERIAL PEPTIDE FROM CHINESE OAK SILKWORM TOTHE PATHOGEN OF BACTERIAL ULCER AND YELLOW SHOOT DISEASE IN CITRUS

In this article,the bactericidal effect of antibacterial peptide(AP)from Chinese oak silkworm pupae,Antheraea pernyi on the growth of the pathogens of bacterial ulcer(Xanthomonas campestris PV citri)and yellow shoot disease(Bacterium like Organism,BLO)was firstly reported.The inducible AP was immunized from the haemolymph of Chinese oak silkworm pupae by injecting with E.coli K12D31.The AP was purified by boiling(100℃,30min).centrifuging and separating with Sephadex G 50.The purified AP was labelled with fluorescince yellow.Both pathogens were treated with 10μg/ml of AP.The optimal effective time was 20─60 min for killing the bacteria.Observation under the laser scanning confocal mi-croscopy and electron scanning microscopy showed that the primary targets of AP were the cell membrane.In the initial action stage,the receptor sites were seriously injured and some small channels were found on the cell surface,then the intracellular substances were pressed out of the cell,at last the cells became empty and died.