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A proton pump is an integral membrane protein pump that builds up a proton ... reducing equivalents provided by electron transfer or photosynthesis power the ...
The electron transport chain of photosynthesis is often put in a diagram called the Z-scheme, because the redox diagram from P680 to P700 resembles the letter Z. [3] The final product of PSII is plastoquinol, a mobile electron carrier in the membrane. Plastoquinol transfers the electron from PSII to the proton pump, cytochrome b6f. The ultimate ...
In photophosphorylation, light energy is used to pump protons across a biological membrane, mediated by flow of electrons through an electron transport chain. This stores energy in a proton gradient. As the protons flow back through an enzyme called ATP synthase, ATP is generated from ADP and inorganic phosphate.
The bacteriorhodopsin changes its configuration in response to sunlight, acting as a proton pump. This produces a proton gradient more directly, which is then converted to chemical energy. The process does not involve carbon dioxide fixation and does not release oxygen, and seems to have evolved separately from the more common types of ...
Here, light energy drives electron transport through a proton pump and the resulting proton gradient causes subsequent synthesis of ATP. In bacteria , the electron transport chain can vary between species but it always constitutes a set of redox reactions that are coupled to the synthesis of ATP through the generation of an electrochemical ...
In most cases the proton-motive force is generated by an electron transport chain which acts as a proton pump, using the Gibbs free energy of redox reactions to pump protons (hydrogen ions) out across the membrane, separating the charge across the membrane. In mitochondria, energy released by the electron transport chain is used to move protons ...
-ATPase or proton pump creates the electrochemical gradients in the plasma membrane of plants, fungi, protists, and many prokaryotes. Here, proton gradients are used to drive secondary transport processes. As such, it is essential for the uptake of most metabolites, and also for plant responses to the environment (e.g., movement of leaves).
Bacteriorhodopsin is a light-driven proton pump. It is the retinal molecule that changes its isomerization state from all-trans to 13-cis when it absorbs a photon. The surrounding protein responds to the change in the chromophore shape, by undergoing an ordered sequence of conformational changes (collectively known as the photocycle). [17]