FIG 5.

Expression of hypD and proC differs between C. difficile and selected commensal Clostridia in rich media supplemented with hydroxyproline. (A) Alignment of hypD and proC across C. difficile and selected commensal Clostridia strains. Each protein sequence was compared against its counterpart in the reference strain C. difficile 630Δerm, generating the amino acid percent identity labeled within each gene. (B–E) Expression of hypD and proC in BHI media and BHI media with 600 mg/L (4.6 mM) hydroxyproline added of C. difficile (B), C. hiranonis (C), C. hylemonae (D), and C. scindens (E). Experiments were run in triplicate, and three biological replicates were performed. The expression in medium supplemented with hydroxyproline was compared to expression in medium without additional hydroxyproline. Statistical significance was determined using Student's t test (*, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001).