柞蚕抗菌肽D杀菌机理研究

STUDIES ON THE BACTERICIDAL EFFECT OF ANTIBACTERIAL PEPTIDE D FROM CHINESE OAK SILKWORM,ANTHERAEA PERNYI

本文研究柞蚕抗菌肽D对水稻白叶枯病细菌及番茄、烟奇、马铃薯青枯病细菌的杀菌作用及其机理。在37°C,pH6.8条件下,最低有效剂量2ng/1×10~5活菌。通过电镜观察,抗菌肽D对大肠杆菌及白叶枯病细菌的作用,首先使其外壁层及细胞质膜损伤,尤以菌体两端更为明显。此后形成喇叭状缺口,内容物呈囊状挤出胞外而致死。抗菌肽作用的菌体表面形成微管通道,钾离子大量渗出,但菌体外形在短时间内不致崩坏。

Antibacterial peptide D from the haemolymph of Chinese oak silkworm, Antheraea pernyi had a strong bactericidal effect on the bacterium of rice leaf blight disease,Xanthomonas campestris Pv oryze and potato wilt disease, Pseudomonas solanacearum. The bactericidal effect was related to the amount of antibacterial peptide and environment such as temperature,pH and nutrition. Ultra-thin section technique was used to study the mechanism of bactericidal effect of antibacterial peptide, the primary targets were the bacteria] outer layer and cell membrane,especially sensitive to the both ends. At initial action stage, the receptor sites were seriously injured and some microtubules were observed. Potassium ion of inner cell leaked out, intracellular subatances were pressed out of the cell subsequently, and cell become empty vesicles.