Inhibition of the yeast V-type ATPase by cytosolic ADP

FEBS Lett. 2003 Jan 30;535(1-3):119-24. doi: 10.1016/s0014-5793(02)03886-3.


The activity of the vacuolar H(+)-ATPase has been characterized in isolated vacuoles of the yeast Saccharomyces cerevisiae by means of the patch-clamp technique. With cytosolic calcium at virtually zero (<10(-9) M), Mg-ATP induced a transient, bafilomycin A(1)-sensitive current corresponding to the flow of positive charges from the cytoplasmic surface to the vacuolar lumen. The Mg-ATP-dependent current reached its maximum amplitude (30+/-8 mA m(-2) with 5 mM Mg-ATP, n=34) within 15-20 s and declined slowly over a period of about 15-20 min even in the continuous presence of Mg-ATP. This decline of pumping activity was independent of the cytosolic KCl concentration, suggesting an inhibitory mechanism different from the high salt-induced dissociation of V(0) and V(1) reported for the V-ATPase of plants and fungi. Cytosolic ADP was found to modulate the pump activity since Mg-ATP-induced pump current was smaller if monitored in the presence of 5 mM ADP and addition of 5 mM ADP in the presence of 5 mM Mg-ATP reduced the pump current by more than 50%. Furthermore, reduction of the cytosolic ADP concentration by the ATP-regenerating system creatine phosphate/creatine kinase partially relieved the endogenous inhibition of the V-ATPase, confirming that interaction of cytosolic ADP with the V-ATPase is the reason for the transient nature of the pump current in yeast vacuoles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Diphosphate / metabolism*
  • Adenosine Diphosphate / pharmacology
  • Adenosine Triphosphate / biosynthesis
  • Adenosine Triphosphate / pharmacology
  • Anti-Bacterial Agents / pharmacology
  • Calcium / metabolism
  • Creatine Kinase / pharmacology
  • Cytosol / metabolism*
  • Electrophysiology
  • Macrolides*
  • Patch-Clamp Techniques
  • Potassium Chloride / metabolism
  • Saccharomyces cerevisiae
  • Subcellular Fractions / chemistry
  • Vacuolar Proton-Translocating ATPases / antagonists & inhibitors
  • Vacuolar Proton-Translocating ATPases / metabolism*
  • Vacuoles / chemistry
  • Vacuoles / drug effects
  • Vacuoles / metabolism*


  • Anti-Bacterial Agents
  • Macrolides
  • Adenosine Diphosphate
  • Potassium Chloride
  • bafilomycin A1
  • Adenosine Triphosphate
  • Creatine Kinase
  • Vacuolar Proton-Translocating ATPases
  • Calcium