What is "in mitochondrial electron transport?

Mitochondrial electron transport, also known as the electron transport chain (ETC), is a series of protein complexes and other molecules embedded in the inner mitochondrial membrane. It plays a crucial role in cellular respiration, specifically in the production of ATP, the cell's primary energy currency.

The primary function of the ETC is to transfer electrons from electron donors, namely NADH and FADH2, to electron acceptors, ultimately leading to the reduction of oxygen to water. This electron transfer is coupled with the pumping of protons (H+) from the mitochondrial matrix into the intermembrane space, creating an electrochemical gradient.

Key components of the ETC include:

• Complex I (NADH dehydrogenase): https://www.wikiwhat.page/kavramlar/Complex%20I%20(NADH%20dehydrogenase) accepts electrons from NADH and transfers them to ubiquinone (coenzyme Q).

• Complex II (Succinate dehydrogenase): https://www.wikiwhat.page/kavramlar/Complex%20II%20(Succinate%20dehydrogenase) accepts electrons from succinate (part of the citric acid cycle) and transfers them to ubiquinone.

• Ubiquinone (Coenzyme Q): https://www.wikiwhat.page/kavramlar/Ubiquinone%20(Coenzyme%20Q) is a mobile electron carrier that shuttles electrons from Complex I and II to Complex III.

• Complex III (Cytochrome bc1 complex): https://www.wikiwhat.page/kavramlar/Complex%20III%20(Cytochrome%20bc1%20complex) transfers electrons from ubiquinone to cytochrome c and pumps protons into the intermembrane space.

• Cytochrome c: https://www.wikiwhat.page/kavramlar/Cytochrome%20c is a mobile electron carrier that shuttles electrons from Complex III to Complex IV.

• Complex IV (Cytochrome c oxidase): https://www.wikiwhat.page/kavramlar/Complex%20IV%20(Cytochrome%20c%20oxidase) accepts electrons from cytochrome c and transfers them to oxygen, reducing it to water. This complex also pumps protons into the intermembrane space.

The proton gradient established by the ETC is then used by ATP synthase (Complex V) to drive the synthesis of ATP through a process called oxidative phosphorylation. https://www.wikiwhat.page/kavramlar/oxidative%20phosphorylation

The flow of electrons through the ETC is tightly regulated to match the cell's energy demands. Inhibitors of the ETC can disrupt ATP production and lead to cell death. Additionally, the ETC can generate reactive oxygen species (ROS) as byproducts, which can cause oxidative stress if not properly controlled. https://www.wikiwhat.page/kavramlar/reactive%20oxygen%20species%20(ROS)