isoenzyme

Isoenzymes
Multiple forms of an enzyme which differ in physical and chemical properties and catalyze the same reaction as an enzyme.
Isoenzymes are produced by a single gene and some may result from more than one gene.
Isoenzymes can be separated by:
1-Heat inactivation
2-Chemical inhibition
3-Electrophoretic techniques (specific)
ISOENZYMES

Catalyze the same reaction.

Differ in AA sequence and physical
properties.

Separable on the basis of charge.
Are tissue specific.

Different Isoenzymes may arise from different tissues and their specific detection may give clues to the site of
pathology.

Isoenzyme variants are derived from different tissue sources.
So separation renders increased specificity to enzyme analysis.
Tissue or organ effected can be detected ( where isoenzyme elevation occurs)

Types
CPK (creatinine Phospho Kinase)
Troponin
LDH (Lactate Dehydrogenase)
ALP (Alkaline phosphatase)
Aldolase
Amylase
CPK-Creatinine Phospho kinase
CPK Isoenzymes are performed when the total CPK level is elevated.
Isoenzyme testing can help differentiate the source of the damaged tissue.
CPK is an enzyme found predominantly in the heart, brain, and skeletal muscle.
CPK is composed of 3 Isoenzymes that differ slightly in structure:
CPK is a dimer made up of 2 subunits called B for brain and M for muscle.