An endogenously produced compound, coenzyme Q10 is found in human cells, and plays an imperative role in production of energy by serving as mobile electron carrier
in electron transport chain within mitochondria.
Coenzyme Q10 (CoQ10) is an essential electron carrier
in the mitochondrial respiratory chain and an important antioxidant.
al., “Vitamin K2 is a mitochondrial electron carrier
that rescues PINK1 deficiency”, Science 336(6086):1306-10 (2012).
Ferredoxin is known as iron-sulphur proteins that function as electron carrier
 in which is an important criteria for sensor.
CoQ10 works as an electron carrier
in the mitochondria, the powerhouse of the cells, to produce energy and is also a powerful antioxidant.
Classification based on the electron carrier