Cycloprodigiosin hydrochloride inhibits acidification of the plant vacuole

Abstract

The effect of cycloprodigiosin hydrochloride (cPrGHCl), obtained from the marine bacterium Pseudoalteromonas denitrificans, on acidification of the vacuole was studied in Characeae cells. In internodal cells of Nitella, the plasma membrane of which had been permeabilized, cPrG-HCl inhibited both ATP- and pyrophosphate-dependent acidification of the vacuole. Application of cPrG-HCl to living internodal cells of Chara, induced a significant increase in vacuolar pH. The role of cPrG-HCl as a tool for studying the physiological role of acidic vacuole is discussed.