Fig 4.

Growth of C. difficile wild-type and mutant strains supplemented with l-proline or glycine. C. difficile wild-type (JIR8094 [○]), LB-CD4 (prdB::ermB [◇]), and LB-CD12 (grdA::ermB [△]) strains were grown in TY medium alone or supplemented with 30 mM l-proline (A) or 30 mM glycine (B). The C. difficile wild type (JIR8094 [●]) was grown in TY medium alone. Cultures were grown anaerobically in a microtiter plate format at 37°C, and OD₆₀₀ measurements were taken every 10 min using a plate reader (Bio-Tek).