重组人血小板型磷脂酶A_2杀菌作用及其抗生素后效应的研究

Study on bactericidal effect of recombinant human platelet phospholipase A_2(PLA_2) and Postantibiotic Effect(PAE)

目的：探讨利用基因工程制备重组人血小板型磷脂酶A2（PLA2）对革兰阳性（G＋）菌及耐甲氧西林金黄色葡萄球菌（MRSA）体外的杀菌作用,并观察其抗生素后效应（PAE）,探讨血小板型PLA2的杀菌机制。方法：采用微量稀释法测定重组人血小板型PLA2对细菌的最低抑菌浓度（MIC）,以菌落平板计数法检测最低杀菌浓度（MBC）和PAE。结果：血小板型PLA2对4种细菌MIC值在0.05-0.2μg/ml之间,MBC值在0.1-0.4μg/ml之间。血小板型PLA2对4种细菌PAE为1.6-24 h。结论：重组人血小板型PLA2对G＋菌有较强的杀菌作用,血小板型PLA2对G＋菌有明显的PAE,具有发展为新型抗菌药物的巨大潜力。

Objective： To explore the bactericidal effect of recombinant human platelet phospholipase A2（PLA2） generated by gene engineering on the gram-positive（G＋） bacteria（including staphylococcus aureus,strphylococcus epidermidis and enterococcus facecalis） and methicillin-resistant Staphylococcus aureus（MRSA）in vitro,the postantibiotic effect and the bactericidal mechanism of PLA2.Methods： Microdilution method was used to determined the minimal inhibitory concentration（MIC） of recombinant human PLA2 on the bacteria.And colony forming unit （CFU） of bacteria was counted by plate method to determine MBC and PAE.Results： The MIC value of PLA2 on the four bacteria was 0.05~0.2 μg/mL, MBC value was 0.1~0.4 μg/mL.The PAZ of PLA2 on the four bacteria was 1.6~24hs.Conclusion： The recombinant human platelet PLA2 possesses a strong bactericidal activity against G＋ bacteria and presents an obvious PAE to the G＋ bacteria,and it has great potentials to be developed as a kind of new anti-bacteria drug.