Search results
Results from the WOW.Com Content Network
Complex III (EC 1.10.2.2) (also referred to as cytochrome b c 1 or the coenzyme Q : cytochrome c – oxidoreductase) is a proton pump driven by electron transport. Complex III is a multi-subunit transmembrane protein encoded by both the mitochondrial (cytochrome b) and the nuclear genomes (all other subunits).
In eukaryotes, NADH is the most important electron donor. The associated electron transport chain is NADH → Complex I → Q → Complex III → cytochrome c → Complex IV → O 2 where Complexes I, III and IV are proton pumps, while Q and cytochrome c are mobile electron carriers. The electron acceptor for this process is molecular oxygen.
Diffusion vs. Transport. In biology, an ion transporter is a transmembrane protein that moves ions (or other small molecules) across a biological membrane to accomplish many different biological functions, including cellular communication, maintaining homeostasis, energy production, etc. [1] There are different types of transporters including pumps, uniporters, antiporters, and symporters.
While these proteins are diverse (taking on both membrane-bound or soluble forms), their common locations in the outer membrane or periplasm in Gram-negative and Gram-positive bacteria provide intimate contact for electron transfer. [10] Additionally, the presence of electron shuttles dramatically increases the direct transfer rate. [4]
The carriers pass electrons to the electron transport chain (ETC) in the inner mitochondrial membrane, which in turn pass them to other proteins in the ETC. The energy at every redox transfer step is used to pump protons from the matrix into the intermembrane space, storing energy in the form of a transmembrane electrochemical gradient.
Oxidative phosphorylation is made up of two closely connected components: the electron transport chain and chemiosmosis. The electron transport chain in the cell is the site of oxidative phosphorylation. The NADH and succinate generated in the citric acid cycle are oxidized, releasing the energy of O 2 to power the ATP synthase.
In biology and ecology, abiotic components or abiotic factors are non-living chemical and physical parts of the environment that affect living organisms and the functioning of ecosystems.
The gastric hydrogen potassium ATPase or H + /K + ATPase is the proton pump of the stomach.It exchanges potassium from the intestinal lumen with cytoplasmic hydronium [2] and is the enzyme primarily responsible for the acidification of the stomach contents and the activation of the digestive enzyme pepsin [3] (see gastric acid).