A Gene Expression In The New Methods Of Change Detection And Identification Of Antibacterial Substances

Since the discovery of the first antibiotic penicillin in 1929, antibiotics have played an essential role in the human health. However, with the emergence and spread of resistance to existing antibiotic among pathogens new antibiotics are urgently needed. The objective of this research was to design and construct an antibiotic screening system using antibiotic responsive genes as reporters.Plasmid pCS26 carrying a promoterless luminescence reporter, luxCDABE, was used as the vector and the promoter regions of antibiotic responsive genes/operons from Escherichia coli were cloned upstream of the lux reporter to form the first part of the screening reporter array. Random promoter library of Salmonella enterica was screened for antibiotic responsive clones which consist of the second part of the screening array.With the selected promoters sensitived to antibiotics from random promoter library of Pseudomonas aeruginosa by early work of lab which consists of the third part of the screening array.We used 12 kinds of antibiotics to screen these genes, to identify the function of antibiotic to the expression of promoters. The selected final reporter array responded to different antibiotics in distinct patterns and enabled in vivo high-throughput screening for antibiotics. Unknown antibiotics could be classified by analyzing the response patterns.And then, we use these genes to screen 30 kinds of different compounds. We found 9 kinds of compounds inhibit the growth of bacteria sensitived to the promoters as antibiotics. Meanwhile, we used these genes to screen the microorganism from soil, and we found 12 bacterial strains snsitived to promoters. This screening system is both sensitive and efficient and should prove to be a useful tool for screening new antibiotic compounds.