FIGURE 12.
Effect of substrates (succinate and Pi) on the hydrolysis and release of synthesized ThTP. The mitochondrial fraction was preincubated (15 min, 30 °C) in the presence of Pi (5 mm), succinate (5 mm), and ThDP (1 mm). Then the samples were washed twice by centrifugation (11,000 × g, 5 min), and the mitochondria were resuspended in saline and incubated for the time indicated either in the absence (A and B) or the presence (C and D) of Pi (5 mm) and succinate (10 mm). After centrifugation (11,000 × g, 5 min), ThTP was determined in the pellets (A and C) and the supernatants (B and D) (mean ± S.D., n = 2–8). ●, control; ○, 0.2 μm CCCP; □, 10 nm valinomycin.