The chemostat device was designed at the Institute for Science and Technology in Vienna, and modified at Purdue University’s School of Biomedical Engineering. It maintains constant growth inhibition via dynamic regulation of antibiotic concentration. It includes components for mixing and aeration of growth media, optical monitoring of bacterial growth rate, and feedback control of antibiotic delivery to the culture. Each team of three participants will be given a pre-assembled chemostat and wild-type strain of V. natriegens.  Following initial tests of the chemostat and natural tolerance of their strain, they will subject their strain to ever-increasing amounts of antibiotics to promote evolution of resistance. Following this, each group will select three mutants to send for sequencing.

The bioinformatics instructor will lead them through QC, de novo assembly or assembly via alignment to the reference genome, and SNP/rearrangement calling to identify mutations  that likely increase resistance. Results from all twelve teams will be compiled and used to map the biological networks that were most apt to give rise to resistance. Participants will analyze the similarities and differences among group results to show how mutations arise spontaneously, but may be conserved to particular susceptible biological functions that allow the bacteria to survive under pressure.  By the end of the 39-day program, teams will have identified the genetic modifications that have arisen, and simulated the natural spread of mutations from selection pressure.