Growth curves of B. suis strains in TS broth (A), in TS broth supplemented with 25 mM erythritol (B), and in minimal medium containing only erythritol (25 mM) as a carbon source (C). The strains used were the wild type (•), the ΔeryC deletion mutant (▵), the complemented ΔeryC mutant containing pBBR1-eryC (▴), and an isolated, spontaneously erythritol-tolerant mutant of ΔeryC (○). One typical set of curves out of three independent experiments performed is shown for each.