FIG 1.

C. difficile ΔhypD mutant has a growth defect when hydroxyproline is substituted for proline in the growth medium. (A) Schematic depicting conversion of trans-4-hydroxy-L-proline to L-proline by HypD, gene hypD (CD630_RS17450), and P5CR, gene proC (CD630_RS17445). (B) Growth of C. difficile 630Δerm WT, the ΔhypD and ΔproC mutants, as well as the complements of both mutants after 24 h of growth in the defined medium CDMM, in CDMM –proline +hydroxyproline (–Pro, +Hyp), and CDMM –proline (–Pro). Statistical significance was determined using Student's t test with Welch’s correction to account for multiple comparisons (*, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001).