Figure 4.

In vivo characterization of FDH variants. (a) Growth profiles of NADPH auxotroph strain with five gene deletions expressing MvaFDH^4M (red line) or PseFDH in the presence of formate (black line) or gluconate (yellow line) as a control. Additional deletion of maeA results in a more robust selection strain (NADPH-aux) that displays slower growth with MvaFDH^4M (red dotted line) in the presence of formate, no growth with PseFDH in the presence of formate (black dotted lines), and full growth with PseFDH in the presence of gluconate (yellow dotted lines). (b) Growth profiles of NADPH-aux when the seven PseFDH variants isolated from the selection are expressed. Strains were cultured in 20 mM glycerol, 3 mM keto-glutarate, and 75 mM formate. (c) Sequencing results of PseFDH variants with doubling time (DT) ± standard error from triplicates.