The accumulation of protons in the intermembrane space creates an electrochemical gradient that causes protons to flow down the gradient and back into the matrix through ATP synthase. The proton motive force occurs when the cell membrane becomes energized due to electron transport reactions by the electron carriers embedded in it. The membrane may be either cytoplasmic membrane as in the case of bacteria or inner mitochondrial membrane as in case of eukaryotes. ... NAD + accepts two e – and two protons from the substrate during catabolic reaction and transfers to the electron transport chain. These bacteria use the energy of light to create a proton gradient using a photosynthetic electron transport chain. Proton motive force is also used to transport substances across membranes during active transport and to rotate bacterial flagella. Electron Transport Chain Definition. 4). ATP is used by the cell as the energy for metabolic processes for cellular functions.. Where Does the Electron Transport Chain … The mitochondrial electron transport chain is a series of enzymes and coenzymes in the crista membrane, each of which is reduced by the preceding coenzyme, and in turn reduces the next, until finally the protons and electrons that have entered the chain from either NADH or reduced flavin reduce oxygen to water. Although the electron transport chain of E. coli transports electrons from NADH (NADH is the electron donor) to acceptors and moves protons (H +) across the plasma membrane similar to mitochondrial electron transport chain, it is quite different from the latter in its construction. Electron Transport Chain. The electron transport chain is a cluster of proteins that transfer electrons through a membrane within mitochondria to form a gradient of protons that drives the creation of adenosine triphosphate (ATP). The electron transport chain is the third step of aerobic cellular respiration. This electron carrier, cytochrome oxidase, differs between bacterial types and can be used to differentiate closely related bacteria for diagnoses. It occurs in both cellular respiration and photosynthesis in mitochondria. The proton gradient established during electron transport is a form of potential energy C. The electron transport chain can be found in the mitochondria of aerobic bacteria and other cells D. The movement of protons down a concentration gradient is an endergonic … This movement of protons provides the energy for the production of ATP. A. Protons are pumped out of the mitochondria by the complexes of the electron transport chain B. Non-photosynthetic bacteria such as E. coli also contain ATP synthase. In fact, mitochondria and chloroplasts are the product of endosymbiosis and trace … Basically, this causes the cell to act like a tiny battery. During various steps in glycolysis and the citric acid cycle, the oxidation of certain intermediate precursor molecules causes the reduction of NAD + to NADH + H + and FAD to FADH 2.NADH and FADH 2 then transfer protons and electrons to the electron transport chain to produce additional ATPs by oxidative phosphorylation .. As mentioned in the previous section on energy, during … Thus, iron oxide-reducing bacteria rely on complex and yet not fully understood electron transport chains to transfer electrons across the cell envelope (reviewed in ref. This relatively simple electron transport chain lacks the reach needed to transport electrons to extracellular electron acceptors, such as iron oxide minerals. The electron transport chain is a sequence of four protein complexes that incorporate redox reactions to create an electrochemical gradient in a complete mechanism called oxidative phosphorylation that contributes to the formation of ATP. 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