What are the differences between an enzyme and a coenzyme?

Question

Accepted Answer

Basis of differentiation

Enzyme

Coenzyme

Definition

Is a protein catalyst that increases the rate of biochemical reactions without altering itself in the process

Is an organic non-protein molecule that enzymes require to effectively perform their catalytic activity

Size

Is a large molecule

Is a small molecule

Nature

Is a globular protein

Is a non-protein molecule

Composition

Composed of amino acids that form a complex 3D structure

May be a vitamin or derivative, not composed of amino acids

Function

Acts as a biological catalyst that facilitates and catalyzes specific chemical reactions in the body

Acts as a helper molecule that facilitates an enzyme’s catalytic activity by transferring electrons or chemical groups during enzymatic reactions

Specificity

Is specific

Is not specific

Involvement in catalytic activity

Is directly involved in catalysis by providing a specific active site for substrates to bind to

Is indirectly involved in catalysis, typically assisting enzymes by accepting or donating chemical groups

Changes after the reaction

Retains its structure and chemical composition throughout the enzymatic reaction

Undergoes chemical change after the enzymatic reaction

Examples

Kinase
DNA polymerase
Amylase
Proteinase

NAD+
ATP
FAD
coenzyme A

Basis of differentiation	Enzyme	Coenzyme
Definition	Is a protein catalyst that increases the rate of biochemical reactions without altering itself in the process	Is an organic non-protein molecule that enzymes require to effectively perform their catalytic activity
Size	Is a large molecule	Is a small molecule
Nature	Is a globular protein	Is a non-protein molecule
Composition	Composed of amino acids that form a complex 3D structure	May be a vitamin or derivative, not composed of amino acids
Function	Acts as a biological catalyst that facilitates and catalyzes specific chemical reactions in the body	Acts as a helper molecule that facilitates an enzyme’s catalytic activity by transferring electrons or chemical groups during enzymatic reactions
Specificity	Is specific	Is not specific
Involvement in catalytic activity	Is directly involved in catalysis by providing a specific active site for substrates to bind to	Is indirectly involved in catalysis, typically assisting enzymes by accepting or donating chemical groups
Changes after the reaction	Retains its structure and chemical composition throughout the enzymatic reaction	Undergoes chemical change after the enzymatic reaction
Examples	Kinase DNA polymerase Amylase Proteinase	NAD+ ATP FAD coenzyme A