Cofactors Coenzymes And Prosthetic Groups.

What do some enzymes need in order to carry out their functions as biological catalysts?

A non-protein helper component.

What are cofactors?

Non-protein components that may either transfer atoms or groups from one reaction to another in a multi-step pathway or form part of the active site of an enzyme.

If a cofactor is an organic molecule, what is it called?

A coenzyme.

How are inorganic cofacotors obtained?

Via diet as minerals, including iron, calcium, chloride and zinc ions.

Where are many coenzymes derived from?

Vitamins, class of organic molecule found in the diet.

What are prospthetic groups?

Cofactors, while some cofactors are loosely or temporarily bound to the enzyme protein in order to activate them, prosthetic groups are tightly bound and form a permanent feature of the protein.

What are enzymes required by?

Certain enzymes to carry out their catalytic function

What are inactive precursor enzymes?

Enzmes produced in an inactive form, particularly enzymes that can cause damage within the cells producing them or to tissues where they are released, or enzymes whose action needs to be controlled and only activated under certain conditions.

What do precursor enzyymes often need to undergo?

A change in shape (tertiary structure), particular to the active site, to be activated. This can be achieved by the addition of a cofactor.

Before the cofactor is added, what is the precursor protein called?

An apoenzyme.

After the cofactor is added, what is the precursor protein called?

A holoenzyme.

Sometimes, how is the change in tertiary structure brought about?

By the action of another enzyme. In some cases, a change in conditions such as pH or temperature results in a change in tertiary structure and activates a precursor enzyme, these types of precursor enzymes are called proenzymes.