Fig. 2

Sample stability of the microbial community of the methanogenic enrichment culture (a, c, e) and the digester sample (b, d, f). The material was stored in PBS at 22 °C (room temperature, black circle), 6 °C (dark grey circle) and (light grey circle) 0 °C (on ice, light grey circle). a, b Absolute numbers of autofluorescent cells (gate F420+). c, d Mean F₄₂₀ fluorescence intensity of cells in gate F420+. e, f Absolute cell numbers of non-autofluorescent cells (gate F420−). The error bars represent the standard deviation of the three replicates