Mitochondrial complex I - energy conversion by a giant proton pump

Program Description

Mitochondrial complex I plays a key role in aerobic energy metabolism. With a molecular mass of almost 1 MDa and more than 40 subunits it is one of the largest membrane protein complexes of the cell. Complex I is a redox-driven proton pump. Electron transfer from NADH to ubiquinone is coupled with proton translocation across the inner mitochondrial membrane. The electrochemical proton gradient established by respiratory chain complexes powers ATP synthase. Dysfunction of mitochondrial complex I is implicated in a number of neuromuscular diseases and neurodegenerative disorders. However, the catalytic mechanism of complex I has remained enigmatic. Recent progress in structure determination provided insight into the molecular basis of energy conversion.