In: Biology
Regarding the electron transport chain, are all of the complexes within the chain integral? Specifically, is complex 2 integral or peripheral? Some images display it as integral, meaning that it does enter the membrane but doesn't span the entirety of it like a transmembrane protein. These different images confuse me, so I'm hoping to get some clarification.
A continuous supply of energy in the form of ATP is essential to the maintenance of life. In most eukaryotes, it is achieved by oxygen-dependent energy production and mitochondrial electron transport chain plays central role in ATP production.
Electron transport chain comprises 4 integral membrane protein complexes
NADH:ubiquinone oxidoreductase (complex I)
Succinate:ubiquinone oxidoreductase (complex II)
Ubiquinol:cytochrome c oxidoreductase/ cytochrome bc1 complex (complex III)
Cytochrome oxidase (complex IV)
The electrons are transferred from NADH and succinate to oxygen through these series of enzymatic complexes of the inner mitochondrial membrane and oxygen is reduced to water. This releases energy and generates a proton gradient across mitochondrial membrane by pumping protons into intermembrane space. The energy of oxidation of hydrogen is used to phosphorylate ADP into ATP. This ATP generation is catalysed by ATP synthase complex (complex V).