Marker Enzyme of Peri Mitochondrial Space
The marker enzyme of the peri mitochondrial space is cytochrome c. Cytochrome c is a small heme protein located in the intermembrane space of mitochondria. It plays a crucial role in the electron transport chain, which is responsible for generating ATP in aerobic respiration.

Cytochrome c Function
- Cytochrome c acts as an electron carrier between complex III and complex IV in the electron transport chain.
- It transfers electrons from complex III to complex IV, where oxygen is finally reduced to water.
- This transfer of electrons is essential for the production of ATP, which is the main energy currency of the cell.

Role as a Marker Enzyme
- Cytochrome c is used as a marker enzyme for the peri mitochondrial space because of its unique location in the intermembrane space.
- Its presence in this specific location indicates the integrity of the mitochondria and the efficiency of the electron transport chain.
- Changes in cytochrome c levels or activity can indicate mitochondrial dysfunction, which is associated with various diseases such as neurodegenerative disorders and metabolic disorders.

Conclusion
In conclusion, cytochrome c serves as the marker enzyme of the peri mitochondrial space due to its crucial role in the electron transport chain and its specific location in the intermembrane space. Monitoring cytochrome c levels can provide valuable insights into mitochondrial function and overall cellular health.

Adenylate kinase