Fig. 3

Autotrophic cultivation of C. drakei with A. woodii [P_bgaL_ldhD_NFP] either in sequential co-culture (squares □) or concurrent co-culture (circles ○). (A), optical density (white) and formate concentration in the medium (grey); (B), substrate consumption with lactate concentration (white) and accumulated pressure loss of the headspace (grey); (C), short-chain products acetate (white) and ethanol (grey); (D), VFA products butyrate (white) and hexanoate (grey). Triplicate cultures were grown with 110 kPa H₂ + CO₂ in the headspace without antibiotics. Recombinant gene expression of A. woodii [P_bgaL_ldhD_NFP] was induced after 15 h, as indicated by the dashed line. The dotted line indicates the addition of C. drakei from a parallel monoculture to the sequential co-culture. For the concurrent co-culture, both strains were inoculated at the start of the cultivation. Plotted data points are the arithmetic mean of three biological replicates. Error bars represent the respective standard deviation