BIOD60H3 Lecture Notes - Lecture 8: Peripheral Membrane Protein, Electrochemical Gradient, Bacteriorhodopsin
Document Summary
The chemiosmotic theory: etc links redox energy to atp synthesis. Experimental evidence for chemiosmosis: mitochondria oxidizes substrates and consume oxygen only when adp is present, mitchell"s proposal: synthetic compounds uncouple oxidation from phosphorylation (using synthetic molecules disrupts the atp synthesis, atpase activity in damaged mitochondria. 46 subunits, ~900kda, possible largest protein in imm. L-shaped, one arm in imm and other into the matrix: contains one fmn and 8 or 9 iron sulfur clusters. Complex ii: succinate coq oxidoreductase: aka succinate dehydrogenase. 2e- from succinate are transferred to fad to form fadh2: fadh2 transfers electrons to coq via fe-s clusters. First round of q-cycle: coqh2 from complex i binds to qo site, one electron is transferred to fe-s protein (r-isp) which releases two protons in to the. Complex iv: cytochrome c oxidase: accepts electrons one at a time from cyt c and donates them to oxygen to form water.
