家蝇抗菌肽的抑菌动力学研究及其机理初探

利用鼠伤寒沙门氏菌针刺诱导家蝇幼虫表达抗菌肽，对抗菌肽的抑菌动力学进行研究，并通过抗菌肽样品对不同细菌动力学特性的研究出发对抗菌肽抑菌作用机制进行探讨。研究发现抗菌肽样品的活性与作用时间有关，24h内出现一到两个活性峰，同一抗菌肽样品对不同细菌的抑菌动力学有差异，抗菌肽的抑菌动力学机制应该与它的的抑菌作用机制有关。通过电镜观测、细胞磷代谢、紫外吸收物测定以及抗菌肽与细菌DNA相互作用结果可知，微生物诱导家蝇表达的抗菌肽样品不仅能够造成细菌细胞的快速坍塌破裂而且能够破坏细胞核心，与DNA结合作用。抗菌肽抑菌动力学的解释：微生物诱导产物中含有两类抗菌肽，一类抗菌肽能造成细胞膜的快速坍塌破裂形成第一个活性峰；另一类抗菌肽可进入细胞，破坏细胞核心，造成紫外吸收物大量外泄形成第二个活性峰。

Investigate antibiosis dynamics and antibacterial mechanisms of Antibacterial Peptides from Musca domestica Larvae

The antibacterial peptides from Musca domestica larvae that were induced by injection with Salmonella typhimurium. Antibiosis dynamics of this antibacterial peptides was investigated. And the antibacterial mechanisms was analyzed. There were one or two activity peaks in 24 hours of the antibacterial peptides sample. The same antibacterial peptides sample had different antibiosis dynamics property for different bacteria. The action time and mode of Musca domestica larvae antibacterial peptides were decided by the characteristic of bacteria cell. The results of scanning electron microscope(SEM) , cell phosphorus metabolism essay, cell ultraviolet absorbate detection and the interaction of antibacterial peptides and cell’s DNA essay showed that the antibacterial peptides of Musca domestica larvae induced by microbe not only effected on the cellular membrane but also influenced the intern structure and function of bacterial cell and binded with bacterial DNA. The interpretation of antibiosis dynamics is that one kind of antibacterial peptides made cellular membrane ruptured caused the first activity peak of antibiosis dynamics, the other kind of antibacterial peptides entered bacterial cell and reacted with genetic material caused the second activity peak.