Bacterial Efflux Pump: Antibiotic Extrusion Simulator

Multidrug efflux pumps are one of the most common — and least visible — resistance mechanisms in Gram-negative bacteria: no mutation to the antibiotic's target and no enzyme that destroys the drug, just an active transporter complex spanning both membranes that ejects the molecule as fast as it diffuses in. This simulator models a population of antibiotic molecules diffusing across a bacterial cell membrane while a tunable number of RND-family pumps (modelled on AcrAB-TolC) actively extrude them via Michaelis-Menten kinetics powered by the proton-motive force. Adjust external drug concentration, membrane permeability, pump count and turnover rate and watch the intracellular concentration converge to a steady state — below or above the lethal threshold — exactly as it would inside a real efflux-overexpressing clinical isolate.