Caught in the 'Death Galaxy'

A new microfluidics chip developed by researchers at Princeton University is showing that bacteria evolve resistance to antibiotics much more quickly, and more predictably, than previously thought, reports Technology Review's Lauren Gravitz. The chip, dubbed the "death galaxy" by its inventor Robert Austin, simulates the complex environment that bacteria experience in the human body — it contains more than 1,000 hexagonal chambers, each of which is a microhabitat, Gravitz says. In his experiment, Austin flowed nutrients around one side of the chip and the antibiotic ciprofloxacin around the other. The solutions flow into the chambers at different concentrations and build different bacterial ecologies in each chamber. The researchers began to see resistant strains emerge within five hours and, after 10 hours, the resistant strains were spreading to cover even the most antibiotic-saturated chambers, Gravitz says. "The researchers also discovered that the evolution occurred predictably. Every time they ran the experiment, they got the same result, with the same four resistance-conferring mutations emerging over and over again," she adds. The chip could be valuable in the development of new antibiotics and could be used to improve strains of beneficial bacteria, like those that are used to degrade pollutants. Austin says he's even planning an application for use in cancer research by using the chip to study how cancer cells develop resistance to chemotherapy.