Cytochrome C

Cytochrome c

The cytochrome complex or cyt c is a small heme protein found loosely associated with the inner membrane of the mitochondrion. It belongs to the cytochrome c family of protein.

Heme Protein

 Protein that contain heme prosthetic group.Heme is bound to the protein either covalently or noncovalently bound or both.

Distribution

Cytochrome c is highly soluble, unlike other cytochrome, and is an essential component of the etc .Cytochrome c is a highly conserved protein across the spectrum of species, found in plant, animals and many unicellular organisms. This along with its small size (weight 12,000  Daltons).It primary structure  consists of a chain of about 100 amino acids ,and  the higher- order organism possess a chain of 104 amino acids.

Functions of cytochrome c:

There are many function of cytochrome c.

1.     In electron transport chain.

2.     Role in apoptosis

3.     As anti-oxidative enzyme.

·        Role in ELECTRON TRANSPORT CHAIN

Cytochrome c oxidize is the last enzyme in the respiratory electron transport change of mitochondria. Its main function is convert molecular oxygen to water and aid in establishing mitochondrial membrane potential.

It is locates the inner membrane which separates the mitochondrial matrix from the intercellular space.

The heme group of cytochrome c accepts electrons from the3 bc1 complex and transfers electrons to the complex IV.

·        Role in Apoptosis

One of the ways cell apoptosis is activated is by release of cytochrome c from the mitochondria in the cytosol.

According to the research that cells are to able to protect from apoptosis by blocking the release of cytochrome C using   BCL-xl. .

Another way the cell can control apoptosis is by phosphorylation, which turn chytochrome c into an anti- apoptosis switch.

·        As  Anti-Oxidative Enzyme:

Cytochrome c is known to play a role in the electron transport chain cell apoptosis,

Recent study shown that it can also acts as an anti-oxidative enzyme in mitochondria and it does so by removing superoxide and hydrogen peroxide from mitochondria, therefore, not only is cytochrome c required in mitochondria for cell respiration, but it is also needed in the mitochondria to limit the production of superoxide and hydrogen peroxide.