as the next step, you decide to test various agents to see if they can inhibit quorum sensing in vitro. you know from work done on a related bacterium that short proteins (peptides) can act as inhibitors of quorum sensing by blocking protein-protein binding events required for signaling. you test a large collection of synthetic peptides and find three candidates that appear to interfere with quorum sensing (peptides 1, 2, and 3). in an experiment similar to the one in the previous part, you grow cultures of wild-type (non-mutant) s. aureus to the same standardized high density and measure the amount of toxin they secrete. for this experiment, however, you mix the candidate inhibitory peptides into the growth medium before starting the cultures. the control culture contains no peptide.