The Action of 2,4-Dinitrophenol on Corn Root Mitochondria

Abstract

A study has been made of the action of a wide range of concentrations of 2,4-dinitrophenol (DNP) on the partial reactions of oxidative phosphorylation. DNP at a concentration of 1 X 10-4M caused classic uncoupling of oxidative phos-phorylation. Higher concentrations inhibited ,phosphorylation and oxidation. The inhibition of oxidation was due to an inhibition of malate dehydrogenase. The P : ° ratio was reduced by uncoupling and inhibition of the enzymes involved in ATP formation.