绿脓杆菌pprA与pprB基因的克隆及其抗药性研究

从绿脓杆菌(Pseudomonas aeruginosa)PAK菌株的染色体DNA构建的基因文库中筛选到一 基因片段与绿脓杆菌的抗性相关。经测序证明该片段包含了绿脓杆菌基因组中PA4293所编码 序列,进一步实验证明与它相邻的另一段827bp的基因也与绿脓杆菌的抗药性有关。上述2基 因分别命名为pprA和pprB。以绿脓杆菌PAK菌株为出发菌株,经过新霉素耐受培养得到抗生素 抗性菌株PAK1-3,该菌株对氨基糖苷类抗生素的抗性明显增强。经PCR方法扩增上述基因并克 隆至PAK1-3菌株中,可引起该菌株对氨基糖苷类抗生素的敏感。又经pprB基因转入临床分离 得到的致病性绿脓杆菌中,导致部分绿脓杆菌对氨基糖苷类抗生素的敏感性增强。pprA和pprB 很可能是一组与绿脓杆菌抗药性相关的双分子调节系统,并与细胞膜的通透性有关。

pprA and pprB cloned and antibiotic resistance in Pseudomonas aeruginosa

Using laboratory strain PAK, a spontaneous P. aeruginora mutant ( PAK1-3) was isolated which displays an increased resistance to various antibiotics especially to aminoglycosides. By complementation of the mutant with genomic clone library derived from the wild type PAK, a novel gene (pprA ) was identified to be able to render PAK1-3 sensitivity to antibiotics. Furthermore, the gene ( pprB ) closed to pprA was observed with the relationship of P. aeruginora . Introduction of a plasmid expressing the pprA and pprB gene into randomly chosen clinical isolates resulted in increased sensitivity to aminoglycosides in majority that have been tested.This slows the pprA and pprB are probably cognate two-component regulatory genes and connected with permeability of cell membrane.