1. INTRODUCTION OF ENZYME IN MEDICINE dr. Ali

What is an enzyme?

An enzyme is a biological catalyst that speeds up chemical reactions in the body without being consumed in the process. They are mostly proteins (except for ribozymes, which are RNA-based).Enzymes lower the activation energy required for reactions, allowing metabolic processes to occur efficiently.

What is a biocatalyst?

A substance (usually an enzyme) that speeds up biochemical reactions.

What are the properties of enzymes?

Colloidal nature in solution. Sensitive to temperature and pH changes. Highly specific in function.

dialyzable

What is a coenzyme?

A non-protein, organic molecule that assists an enzyme in catalyzing reactions, often derived from vitamins.

Examples of coenzymes?

NAD+ (from niacin) – involved in redox reactions. FAD (from riboflavin) – helps in energy metabolism. Coenzyme A (CoA) – important for fatty acid and carbohydrate metabolism. Thiamine Pyrophosphate (TPP) – assists in decarboxylation reactions. Biotin – carries carbon dioxide in carboxylation reactions.

How are enzymes classified?

Enzymes are classified by the International Union of Biochemists (IUB) into six major classes based on function.

What are the six enzyme classes?

Oxidoreductases – Catalyze oxidation-reduction reactions. (Example: LDH) Transferases – Transfer functional groups. (Example: ALT) Hydrolases – Break bonds by adding water. (Example: Amylase) Lyases – Add/remove groups to form/break double bonds. (Example: Fumarase) Isomerases – Rearrange atoms within a molecule. (Example: Phosphoglucoisomerase) Ligases – Join two molecules using ATP. (Example: DNA Ligase)

How are enzymes used in medicine?

Enzymes are critical in: Diagnosis – Measuring enzyme levels to detect diseases. Therapy – Enzyme-based treatments for diseases. Laboratory analysis – Used in biochemical assays.

What are plasma function-specific enzymes?

Enzymes synthesized in the liver, secreted into plasma, and involved in blood clotting, immunity, and lipid metabolism.

Examples of plasma function-specific enzymes?

Coagulation Factors – Help in blood clot formation (e.g., Prothrombin, Fibrinogen). Complement Factors – Aid the immune system (e.g., C3, C5-C9). Lipoprotein Lipase – Breaks down fats. Ceruloplasmin – Involved in copper and iron metabolism. Renin – Regulates blood pressure. Cholinesterase – Breaks down neurotransmitters.

What are plasma non-specific enzymes?

Enzymes normally found in low plasma concentrations but increase due to tissue damage.

Examples of plasma non-specific enzymes?

Creatine Kinase (CK) – Muscle and brain; marker for heart attack. Alkaline Phosphatase (ALP) – Liver and bones; marker for liver disease and bone disorders. Lactate Dehydrogenase (LDH) – Multiple tissues; marker for tissue damage. Aspartate Aminotransferase (AST) – Liver, heart, and muscles; marker for liver damage and heart attack. Alanine Transaminase (ALT) – Liver-specific; marker for hepatitis. Aldolase – Muscle enzyme; elevated in muscle disease.

Why do plasma non-specific enzymes appear in the blood?

They are released when cells are damaged due to injury, disease, or stress.

How are enzymes used therapeutically?

Streptokinase/Urokinase – Dissolves blood clots in heart attack or stroke. Recombinant Tissue Plasminogen Activator (rtPA) – Emergency stroke treatment. Papain – Anti-inflammatory enzyme from papaya.

What are enzymatic markers?

Specific enzymes that indicate organ damage or disease when found in abnormal levels in the blood.

What enzymes are used to diagnose a heart attack?

Creatine Kinase-MB (CK-MB) – Peaks at 24 hours, indicates myocardial infarction. Lactate Dehydrogenase (LDH) – Peaks later, useful when CK-MB is inconclusive. Aspartate Aminotransferase (AST) – Can indicate myocardial infarction or liver damage.

What enzymes indicate liver damage?

Alanine Transaminase (ALT) – Specific to liver, rises in hepatitis. Aspartate Aminotransferase (AST) – Rises in liver and heart damage. Alkaline Phosphatase (ALP) – High in bile duct obstruction and liver disease. Gamma-Glutamyl Transferase (GGT) – Elevated in alcoholic liver disease. 5’-Nucleotidase (5’NT) – Used alongside ALP for bile duct disorders.

What enzymes indicate pancreatic disease?

Amylase – Elevated in acute pancreatitis. Lipase – More pancreas-specific, remains elevated longer.

What enzymes indicate muscle disease?

Aldolase – Muscle damage, muscular dystrophy. Creatine Kinase-MM (CK-MM) – Skeletal muscle damage.

What enzymes indicate prostate disease?

Acid Phosphatase (ACP) – Elevated in prostate cancer. Prostate-Specific Antigen (PSA) – More specific marker for prostate cancer.

What enzymes indicate bone disorders?

Alkaline Phosphatase (ALP-Pre Beta) – Elevated in Paget’s disease, bone tumors, osteomalacia. Gamma-type ALP – May be high in ulcerative colitis.

What other enzymes serve as disease markers?

Cholinesterase – Low in liver disease or pesticide poisoning. Glucose-6-Phosphate Dehydrogenase (G6PD) – Deficiency causes hemolytic anemia. Ceruloplasmin – Low in Wilson’s disease (copper accumulation).

How are enzymes used in genetic engineering?

Restriction Endonucleases – Cut DNA for genetic manipulation. Taq DNA Polymerase – Used in PCR (DNA amplification).

How are enzymes used in industry?

Rennin – Used in cheese production. Glucose Isomerase – Converts glucose to high-fructose corn syrup. Proteases – Used in detergents.