Resistance Of Multi-drug Resistant Bacteria Establishment And Application Of Drug Screening Model

The appearance and spreading of drug resistant and multidrug resistant bacteria is always reminding people of finding new mechanical antibacterial drugs to combat the threat of these mutants. Multidrug resistant bacterial infection is one of the most serious problems in clinical curation. But multidrug resistant bacteria can also be whole-cell models for screening anti multidrug resistant bacterial drugs. In this paper, we reported that one multidrug resistant bacterium bxg-zu was isolated from dead abalones. It showed high level drug resistance of multi common clinical drugs. The sequencing result of bxg-zu’s 16S rDNA showed that it was Morganella morgani strain. We used this multidrug resistant bacterium to build drug screening model and screened 3192 synthetic chemicals and 6400 microbial fermentation broths. The preliminary hit rates of chemicals and microbial fermentation broths screening were 0.44% and 0.59% separately. One chemical named 2-Bromo-2-nitro-1,3-propanediol (Bronopol) and one microbial fermentation broth numberd I08A-1776 which overcame the multidrug resistant mechanism were discovered by secondary screening. The antibacterial test results showed that they had both anti gram-negative and gram-positive bacterial activities especially anti Mycobacterium tuberculosis (MTB) activities.3 pure chemicals 1-3 were isolated from fermentation broth I08A-1776 and proved to be new structural streptothricin antibiotics. The main active compound of the microbial metabolites was still under isolation. But the results of UV and LC-MS showed that this compound could also be streptothricin antibiotic.