两性多肽结构影响鲍曼不动杆菌外膜通透性的实验研究  

Effects of the amphiphilic peptides on membrane permeability of Acinetobacter baumannii

作　　者：张劼[1] 陈永[1] 曾颖[1] 李秀娟[2] 

机构地区：[1]重庆市第三人民医院老年病科,400014 [2]重庆医科大学附属第一医院第一分院内科,400015

出　　处：《重庆医学》2015年第9期1162-1164,1167,共4页Chongqing medicine

基　　金：重庆市卫计委科研基金资助项目(2013-2-097);重庆市渝中区科技计划基金资助项目(20130149)

摘　　要：目的明确两性多肽结构对鲍曼不动杆菌(AB)外膜通透性的影响。方法 PCR扩增LysAB3基因及删除两性多肽结构的LysAB3-D基因,以pET28a(+)为载体构建重组质粒,在大肠杆菌BL21(DE3)中表达LysAB3及LysAB3-D,金属离子螯合亲和层析法纯化重组蛋白。将AB分别经LysAB3及LysAB3-D处理后,用扫描电子显微镜观察菌体形态,荧光显微镜观察菌体中是否有绿色荧光的聚集。结果经LysAB3处理后的AB,在扫描电子显微镜下可见菌体表面粗糙、皱缩,部分裂解为碎片;在荧光显微镜下可见菌体内有绿色荧光聚集。而删除两性多肽结构的LysAB3-D作用AB后,却没有上述现象的发生。结论两性多肽结构可增加AB外膜通透性,有助于裂解酶进入其中,达到抗菌目的。Objective To investigate effects of the amphiphilic peptides on membrane permeability of acinetobacter bauman-nii .Methods The LysAB3 and LysAB3-D （lack of amphiphilic peptides structure gene） was synthesized and inserted into the vec-tor pET28a（＋ ） to construct the recombinant expression plasmid （pET28a-LysAB3 ,pET28a-LysAB3-D） .After expression in E . coli BL21（DE3） and purification with Ni2＋-NTA Sepharose .Acinetobacter baumannii was observed by scanning electron microsco-py and fluorescence microscope ,pretreated with LysAB3 and LysAB3-D respectively .Results Under scanning electron microscopy , LysAB3-treated acinetobacter baumannii exhibited not only significant abnormalities ,including deep roughening of the cell surface , but also FITC readily accumulated in bacteria .It was different from LysAB3-D-treated .Conclusion These results indicate that the amphiphilic peptides structure increase membrane permeability of acinetobacter baumannii ,which helps LysAB3 degrade bacteria .

关 键 词：噬菌体 裂解酶 两性多肽结构 鲍曼不动杆菌 外膜通透性 

分 类 号：R378[医药卫生—病原生物学]