The fdx5 mutant is unable to grow and has attenuated respiration and photosynthesis rates in the dark. (A) Colonies of WT, fdx5, and two rescued strains [fdx5(FDX5)-1 and fdx5(FDX5)-2] after 9 d of growth on solid TAP medium in the light and dark. The medium was unsupplemented, supplemented with paromomycin (Paro), or supplemented with paromomycin and Zeocin (Paro + Zeo). (B) Growth of WT, fdx5, and two rescued strains in liquid TAP medium over 7 d in the light and dark. (C) Respiratory O2 consumption after transferring WT cells, fdx5, and the fdx5(FDX5) complemented strain from the light to the dark for various times (1–48 h). (D) Photosynthetic O2 evolution in saturating actinic light after transferring WT cells, fdx5, and the fdx5(FDX5) complemented strain from the light to the dark for various times (1–48 h). The results for the various strains are given in different colors, as indicated. Error bars for B, C, and D represent SD (n = 3); experiments were performed in triplicate.