OBJECTIVETo establish an efflux pump inhibitor screening model with the out-membrane protein OprM in Pseudomonas aeruginosa efflux pump system as the target point.

METHODSEfflux pump out-membrane protein gene oprM was obtained from standard Pseudomonas aeruginosa PA01 strain. Expression of OprM protein was induced in E. coli strain HS151 with T-easy vector as the cloning vector, and pMMB67EH as the expression vector. In order to evaluate the function of OprM protein, we measured intracellular tetracycline concentrations with liquid scintillation counter, measured the diameters of bacteriostatic circles with paper disc, and then established a screening model accordingly.

RESULTSOprM protein was highly expressed. Using Pseudomonas aeruginosa as the main detecting bacteria, we established a drug screening model acting on OprM. A total of 1 600 microbial fermentation samples were screened with this model, among which 56 positive strains were found, with a positive rate of 3.5%.

CONCLUSIONOprM plays an important role in drug efflux. The established model has good specificity and maneuverability.