FIG 1.
CbpB is toxic in the absence of c-di-AMP. (A) dacA deletion mutants are unable to grow on rich media unless there is a second mutation in cbpB that renders it nonfunctional. All three strains grow on complete listeria synthetic medium (cLSM). (B) Construction of a strain to test CbpB function. The dacAfl cre-cbpB strain was engineered to flox the dacA gene while constitutively expressing cbpB. (C) When plating this strain on actA-activating medium, the resulting mutant is ΔdacA Phyper-cbpB. Plating this strain on actA-activating medium also resulted in a plating deficiency, which was restored by the addition of L. monocytogenes dacA or B. subtilis disA.