Studies of the adenosine triphosphate-adcnosine diphosphate exchange reaction of phosphorylating submitochondrial particles first described by Cooper and Lehninger (l), and subsequently studied in detail by Bronk and Kielley (2), and Wadkins and Lehninger (3) have provided evidence that this exchange reaction is a manifestation of the terminal step of oxidative phosphorylation in which ADP reac...

It has been claimed that barbiturates uncouple oxidative phosphorylations (Brody & Bain, 1954; Brody, 1955). These authors have demonstrated that during the oxidation of pyruvate by liver and brain mitochondria, phosphate uptake was lowered proportionately more than oxygen uptake. Support for the uncoupling theory was derived from certain similarities between the barbiturates and 2:4dinitrophen...

Respiration-linked contraction of corn mitochondria is not noticeably reduced by low, uncoupling concentrations of dinitrophenol. However, if a contraction/respiration ratio is calculated, the contraction proves to be uncoupled. Previous statements that contraction cannot be uncoupled from respiration are in error.The uncoupling of contraction is consistent with the concept that dinitrophenol a...

Previous studies have shown that Ca influx increased but Ca efflux did not change during the contracture of taenia coli induced in hypertonically added 40 mm potassium solution (1) and the results were supported by the others (2-6). Further, the movements of Ca in the muscle in high-K solution might be differently affected by ouabain and 2, 4-dinitrophenol during the abolition of the tonic tens...

The uncoupler 2,4-dinitrophenol blocks the final step of lipopolysaccharide assembly--transfer of O antigen from undecaprenyl pyrophosphate to core lipopolysaccharide--in intact Salmonella typhimurium but not in isolated membrane fractions. The O-antigen ligase enzyme is not inhibited by dinitrophenol in vitro, and core lipopolysaccharide synthesized in the presence of uncoupler in vivo is func...

0 2 4 6 8 Time of incubation at 30°C in shaking water bath (h) Fig. 1. Survival of cytochrome P-450 when shaken aerobically at 30°C in 0.1 M-potassium phosphate bufler: protection by chloramphenicol, cycloheximide, dinitrophenol and semianaerobic conditions Symbols: @ 0.1 M-phosphate buffer + 20% glucose + 1 mMchloramphenicol; A, 0.1 M-phosphate buffer + 20% glucose + 1 m~-2,4-dinitrophenol; 0,...