CP7抗菌蛋白对嗜水气单胞菌的抑杀作用机理

目的]研究多粘类芽孢杆菌(Paenibacillus polymyxa) CP7菌株的抗菌蛋白(CP7ACP)对嗜水气单胞菌的抑杀作用机理,为防治嗜水气单胞菌引起的鱼病提供新的潜在天然药物.方法]采用抑菌试验、钼锑抗比色法和紫外光谱法研究其对嗜水气单胞菌S12菌株生长、磷泄漏和生物大分子的影响,并利用扫描电镜和透射电镜观察了嗜水气单胞菌细胞结构遭受的破坏作用.结果]CP7ACP对嗜水气单胞菌的抑菌圈直径约8.1 mm,最小抑菌浓度(MIC)与最小杀菌浓度(MBC)分别为原液浓度的1/8和1/4;嗜水气单胞菌受CP7ACP处理后,电镜观察发现其细胞壁、细胞膜、细胞器以及菌体均受到不同程度的破坏,胞内的生物大分子和磷泄漏明显,基因组DNA发生增色效应.结论]CP7ACP抑制嗜水气单胞菌生长,可用于防治嗜水气单胞菌引起的鱼病.

Mechanism of CP7 antibacterial protein against Aeromonas hydrophila

Objective] The efficacy of the CP7 antimicrobial proteins (CP7ACP) to Aeromonas hydrophila was evaluated to provide potential novel natural drug for treating fish disease caused by Aeromonas hydrophila. Methods] The effect on Growth, phosphorus divulges and biomacromolecule of Aeromonas hydrophila S12 were tested using Antibacterial test, Mo-Sb colorimetry and UV spectroscopy, while destructive effects of Aeromonas hydrophila cell structure by CP7ACP were observed under both scanning electron microscope and transmission electron microscope. Results] The inhibition zone diameter was about 8.1 mm, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was 1/8 and 1/4 of stock solution respectively. After treated by CP7ACP, electron microscope reveals that cell wall, membrane, organelles and the thallus of Aeromonas hydrophila are subject to different degrees of damage, while intracellular biomacromolecule and phosphorus significantly divulge, genomic DNA become hyperchromic effect. Conclusion] CP7ACP inhibit the growth of Aeromonas hydrophila, can be used for preventing fish disease caused by Aeromonas hydrophila.