Panel A: Freshly grown cells of wild type yeast (MR6), atp6-L247P mutant (RKY38), and a strain lacking the leader peptide of Atp6p (RKY48, atp6-Δleader) [] were serially diluted and 5 μl of each dilution spotted onto glucose (YPGA) and glycerol (N3) plates, and onto glycerol plates containing the indicated concentrations of oligomycin (Oligo). The plates were incubated at 28°C and photographed after 4 days. Panel B: Growth of yeast atp11 mutants on EG ± oligomycin. Wild type and atp11 mutant strains described in [] were grown overnight on rich glucose plates (2% glucose, 2% bactopeptone, 1% yeast extract), replica-plated to non-fermentable media (3% glycerol, 2% ethanol, 2% bactopeptone, 1% yeast extract) that was either untreated (EG) or supplemented with oligomycin to 2% (EGO), and incubated at 30°C for 48 h. From top to bottom, the strains analyzed were W303-1A, W303ΔATP11, and W303ΔATP11 transformants harboring plasmids for Atp11(R183)p, Atp11(Δ40–111)p, Atp11(Δ40–75)p, or Atp11(A300)p. The amount of oligomycin-sensitive ATPase activity measured in mitochondria isolated from each strain is shown on the left. For stylistic reasons, two separate regions of the same photograph were fused (white dotted line) to create the digital image of the EG and EGO plates shown in the figure.