Fig. 4

Induction of WatR target genes by acetate but not lactate. The wild-type and ΔwatR (JHM15) strains were grown in NMS media with 20% (v/v) methane until early exponential phase and then treated with 0.15 g/L lactate (A) or 0.6 g/L acetate (B) for 10 min. Transcript levels were detected by qRT-PCR and indicated as values relative to those of untreated wild type. Each value represents the average ± standard deviations from two (for lactate) or three (for acetate) independent experiments. Significant difference from wild-type strain is shown as *p < 0.1; **p < 0.05