Cofactors and coenzymes Flashcards
What is a cofactor?
A non-protein which, alongside a protein, enzymes consist of
How do cofactors bind?
Loosely to the enzyme or form part of the active site to activate them
What do cofactors do?
They help the enzyme to carry out it is function by transferring atoms or groups from one reaction to another in a metabolic pathway
What are the two types of cofactors?
Organic or inorganic
How are inorganic cofactors taken in?
Through the diet as mineral ions
What are examples of inorganic cofactors?
Zinc, iron, calcium and chloride ions
What is an example of how inorganic cofactors are used?
Amylase, which breaks down starch to maltose, needs the chloride ion to help form the correct shape of the active site
What is another name for organic cofactors?
Coenzymes
Where are coenzymes derived from?
From vitamins such as Vitamin B3 which is used to synthesis the coenzyme NAD (nicotinamide adenine dinucleotide)
What does NAD do?
It transfers hydrogen atoms between molecules in the reactions in respiration
How is NAD needed?
The enzyme alcohol dehydrogenase needs NAD to transfer hydrogen in the conversion of ethanal to ethanol in anaerobic respiration
What is an example of a vitamin used to make a co-enzyme?
Vitamin B5 is used to make co-enzyme A which is essential in the breakdown of fatty acids and carbohydrates in respiration
What are prosthetic groups needed for?
They are required by enzymes to carry out their function so are a type of cofactor
How do prosthetic groups bind?
They are permanently and tightly bound to the enzyme
What is an example of a prosthetic group?
Carbonic anhydrase is involved in the metabolism of carbon dioxide and it has a zinc ion, forming an important part of its structure
