Fig. 4. Acridine Orange uptake into isolated vacuoles from stv1
and
vph1 strains shows diminished activity. Yeast vacuoles were
isolated by Ficoll gradient centrifugation and adjusted to a protein
concentration of 2 mg ml-1
(Uchida et al., 1985).
ATP-dependent proton uptake was measured by following Acridine Orange
absorption changes (A) at 491-540 nm. Vacuoles containing 10
µg of protein were assayed in each sample. Where indicated by an arrow, 10
µl of 0.1 mol l-1 MgATP or 1 µl of 1 mmol l-1
carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone (FCCP) was
added.
