FIG. 2.

Mutation of the Cj0572 gene in C. jejuni NCTC11168 results in riboflavin auxotrophy, which can be overcome by supplementation with exogenous riboflavin or the riboflavin precursor diacetyl. (A) Growth curves of the wild-type (WT) strain and the ribB (Cj0572) mutant in riboflavin-free MEMα with 20 μM FeCl₃, with and without supplementation with 500 μM riboflavin. (B) Growth curves of the ribB (Cj0572) mutant strain in riboflavin-free MEMα supplemented with 20 μM FeCl₃ and a range of riboflavin concentrations. (C) Growth curves of the C. jejuni NCTC11168 wild-type strain (WT) and ribB mutant in response to exogenous diacetyl. Cultures were grown in MEMα without riboflavin, supplemented with 20 μM FeCl₃ at 37°C, with or without 50 μM diacetyl. Data shown are from two independent growth experiments, each performed in triplicate. Error bars indicate standard deviations.