The antibiotic bacitracin inhibits the synthesis
of bacterial cell walls. A disk (TaxoA) impregnated
with a small amount of bacitracin (0.04
units) is placed on an agar plate, allowing the
antibiotic to diffuse into the medium and inhibit
the growth of susceptible organisms. After incubation,
the inoculated plates are examined for
zones of inhibition surrounding the disks.