家蝇抗菌肽对细菌细胞表面特性影响及其作用机理的研究

Effect on the Bacterial Cell Surface Characteristics and Cell Membrane of the Antibacterial Peptide of Housefly(Musca domestica)

摘要:

利用微生物对十六烷吸附的方法(MATS方法)、微电泳方法与测定细菌质膜上β-半乳糖苷酶活性的方法，探讨了家蝇抗菌肽对大肠杆菌等6种细菌细胞表面特性及其细胞膜的作用机制。研究结果表明，抗菌肽使细菌表面电负性增强，对G⁺细菌细胞表面电荷的改变大于对G^-的改变，使细菌细胞表面疏水性不同程度的下降。抗菌肽引起细菌细胞膜通透性迅速增加，不同细菌β-半乳糖苷酶释放的最大速度V_P在3.86pmol/min～6.92 pmol/min，相应的时间T_P为0，由此推测抗菌肽对细胞膜的作用机制是“形成孔洞"。

Abstract:

Effect on the bacterial cell surface characteristics and cell membrane of the antibacterial peptide of the larvae of housefly (Musca domestica) was studied by MATS, microelectrophoresis and measuring the hydrolysis of o-nitrophenyl-L-D-galactoside(ONPG) by the cell β-galactosidase. The results indicated that the antibacterial peptide of the housefly larvae could increase the negative charge of the cell surface, more potently to the G⁺ than the G^-, and could decrease the hydropobicity of the cell surface. The results also suggested that the antibacterial peptide could increase the permeability of the cell membrane, the regression equation of the time course of o-nitrophenol(ONP) was obtained, and the maximum velocity of ONPG hydrolysis(V_P) was calculated to be 3.86 pmol/min-6.92 pmol/min for various tested bacteria at 0 minute.It was suggested that the antibacterial peptide may act on the cell membrane through the “pore forming " mechanism.