Fig. 2

Growth and H2 production during fermentative growth. The graphs show growth curves (a) and H2 concentration (b) during pyruvate fermentation (40 mM pyruvate) by Sulfurospirillum spp. and D. hafniense strain DCB-2, each after adaptation. The graphs are representatives of three independent replicates; the graphs of the latter are presented in Supplementary Figures 4 and 5. S.m. S. multivorans, S.d. S. deleyianum, S.c. S. cavolei, S.a. S. arsenophilum, D.h. D. hafniense DCB-2