Mycobacterium smegmatis containing a green fluorescent protein (GFP) gene grown in a microfluidic chip, treated with rifampicin (the most important anti-TB drug) and stained. Dead bacteria appear red, and live bacteria (expressing GFP) are green. These are potential persister bacilli, surviving the drug treatment. (Submitted by Suzie Hingley-Wilson, Nan Ma and Johnjoe McFadden, University of Surrey)
