ATP-driven proton fluxes across membranes of secretory organelles.

S. Cidon, H. Ben-David, N. Nelson

Research output: Contribution to journalArticlepeer-review

Abstract

The ATP-dependent proton uptake by chromaffin granule membranes, lysosomes, and synaptosomes was examined. In synaptosomes the reaction was absolutely dependent on the presence of chloride, while in chromaffin granules chloride had a profound effect and in lysosomes only a minor effect. The presence of chloride markedly increases the rate of collapse of delta pH by carbonyl cyanide p-trifluoromethoxyphenylhydrazone in all three organelles. Ascorbate with phenazine methosulfate uncoupled the ATP-dependent proton uptake by chromaffin granules, but had no effect on lysosomes and synaptosomes. Proton uptake by submitochondrial particles was about 50-fold more sensitive to dicyclohexylcarbodiimide than the proton uptake by chromaffin granule membranes. Chromaffin granule membranes were treated with 2 M sodium bromide to inactivate the mitochondrial ATPase. The treatment caused a complete inhibition of the ATP-dependent proton uptake. Solubilization of these membranes by sodium cholate, followed by reconstitution by cholate dilution revealed the ATP-dependent proton uptake of the system. It is concluded that the genuine ATPase enzyme of chromaffin granules is a proton translocator.

Original languageEnglish
Pages (from-to)11684-11688
Number of pages5
JournalJournal of Biological Chemistry
Volume258
Issue number19
StatePublished - 10 Oct 1983

Fingerprint

Dive into the research topics of 'ATP-driven proton fluxes across membranes of secretory organelles.'. Together they form a unique fingerprint.

Cite this