What does cytochrome c reduce?
What does cytochrome c reduce?
Cytochrome c oxidase, the terminal enzyme of cellular respiration in mitochondria and many bacteria, reduces O2 to water. This four-electron reduction process is coupled to translocation (pumping) of four protons across the mitochondrial or bacterial membrane1; however, proton pumping is poorly understood.
What are the Colours of the oxidised and reduced species of cytochrome c?
Cytochrome c changes to orangish brown upon reduction, whereas TMBZ changes to greenish blue upon oxidation.
Where is cytochrome found in mitochondria?
mitochondrial intermembrane/intercristae spaces
In healthy cells, cytochrome c (Cyt c) is located in the mitochondrial intermembrane/intercristae spaces, where it functions as an electron shuttle in the respiratory chain and interacts with cardiolipin (CL).
What is the role of cytochrome c in the electron transport chain?
Cytochrome c is functionally involved in the electron transport chain of mitochondria. That electron transport is part of the pathway for synthesis of ATP. The role of cytochrome c is to carry electrons from one complex of integral membrane proteins of the inner mitochondrial membrane to another (Fig. 10.3).
How does cytochrome c cause apoptosis?
During cell apoptosis cytochrome c is released into the cytoplasm where it binds and activates the apoptotic protease activating factor-1 (Apaf-1) allowing its binding to ATP and the formation of the ring-like apoptosome.
What happens when cytochrome c is oxidized?
Cytochrome c is oxidized by mitochondrial cytochrome oxidase (COX) and in this oxidized form (Cyt. cox) it binds to Apaf-1 forming the apoptosome which activates pro-caspase-9 leading to apoptosis. Cytosolic cytochrome c can be reduced (Cyt.
Do cytochromes oxidize or reduce?
Cytochromes are proteins containing a haem (page 371) prosthetic group, the iron atom in the haem group being alternately oxidized and reduced by the transfer of electrons.
What is the function of cytochrome?
Cytochrome c is primarily known for its function in the mitochondria as a key participant in the life-supporting function of ATP synthesis. However, when a cell receives an apoptotic stimulus, cytochrome c is released into the cytosol and triggers programmed cell death through apoptosis.
How are cytochromes formed?
Cytochromes c They are monomeric proteins, containing a heme c moiety, with the proximal and distal ligands formed by histidine and methionine residues. They usually contain a single heme per molecule; however, molecules containing up to eight heme residues are found in certain photosynthetic bacteria.
How do cytochromes transfer electrons?
Electron transfer from cytochrome c occurs by electrostatic binding to subunit II, which should be followed by electron transfer through the CuA center to heme a or heme a3, see Figure 1. Heme a is coordinated by two axial histidine ligands (His102 and His421) provided from different helices.
What is the consequence of cytochrome c translocation in apoptosis?
We showed that cytochrome c, released from mitochondria upon apoptosis induction, gradually accumulates in the nucleus as evidenced by both immunofluorescence and subcellular fractionation.