Fig. 1

Schematic illustration of the concept of this study. In S. cerevisiae, acidic organelle vacuoles occupy a large part of the intracellular volume. The ATP-consuming proton pump V-ATPase constantly translocates H⁺ from the cytosol to the vacuolar lumen to maintain the acidification of vacuoles. Reducing the amount of ATP consumed by V-ATPase should increase the ATP supply for the bioproduction of valuable compounds in S. cerevisiae. In this study, the non-ATP-consuming light-driven H⁺ pump dR was introduced into the vacuolar membrane. The introduced dR translocates H⁺ from the cytosol to the vacuolar lumen under light conditions