Acceleration of Emergence of BActerial Antibiotic Resistance in Connected Microenvironments

Emergence of resistance to antibiotics by bacteria is a fundamental problem, yet the variables that influence the rate of emergence of resistance are not well understood. In a microfluidic device designed to mimic naturally occurring niches, the time to emergence of resistance of Escherichia coli (E. coli) to the antibiotic Ciprofloxacin occurred within 10 hours. Resistance emerged with as few as 100 bacteria in the initial inoculation. Whole-genome sequencing revealed the fixation of four functional single nucleotide polymorphisms (SNPs). The principles of rapid emergence of resistance in heterogeneous environments may apply generally in chemotherapy.