Electron transfer between complexes III and IV in S. cerevisiae mitochondrial membranes
Abstract
Mitochondrial oxidative phosphorylation relies on cytochrome c transferring electrons between complexes III and IV. Earlier studies using detergent‐purified complex III‐IV supercomplexes from S. cerevisiae showed that this transfer is limited by two‐dimensional cytochrome c diffusion. This study investigates this process in membrane‐embedded mitoplasts. The results show that membrane embedment shifts the rate‐limiting step from cytochrome c ‐mediated electron transfer to the catalytic activity of the supercomplex itself. Up to a cytochrome c : supercomplex ratio of unity, turnover increases sharply regardless of ionic strength. At higher ratios, the rate levels out at 15–20 s −1 , indicating that the process is no longer limited by salinity‐dependent electron transfer, but rather by the catalytic capacity of complex IV.
Fields of Study & Subjects
Mitochondrial Function and Pathology
ATP Synthase and ATPases Research
Photosynthetic Processes and Mechanisms
Publication details
- Journal / source
- FEBS Letters
- Publisher
- Wiley
- Volume
- 600
- Issue
- 15
- Pages
- 2108–2116
- Publication date
- 16 June 2026
- Language
- EN