ENZYME

Enzyme

A biological catalyst that increases the rate of reactions without being changed at the end.

Activation Energy

The energy required to convert reactants to products, which enzymes lower.

Globular Proteins

Most enzymes are this type of protein, which is water-soluble.

Specificity

Most enzymes are specific to certain substrates, like trypsin for peptide bonds.

Active Site

The specific portion of an enzyme where a substrate binds during a reaction.

Enzyme-Substrate Complex

The intermediate formed when an enzyme binds to its substrate.

Lock and Key Model

A model where the enzyme's active site is rigid and only fits specific substrates.

Induced Fit Model

A model where the enzyme's active site is flexible and adjusts to fit the substrate.

Factors Affecting Enzyme Activity

Temperature, pH, substrate concentration, and enzyme concentration.

Optimum Temperature

The temperature at which an enzyme is most active, typically around 37°C.

Optimum pH

The pH level at which an enzyme functions best, which is 7.4 in the body.

Competitive Inhibitor

An inhibitor that resembles the substrate and competes for the active site.

Noncompetitive Inhibitor

An inhibitor that binds to an enzyme and changes its shape, preventing substrate binding.

Enzyme Cofactors

Metal ions that assist enzymes in catalyzing reactions, obtained from food.

Vitamins

Organic molecules required from the diet that can act as coenzymes.

Zymogens

Inactive enzymes that become active after a chemical change.

Enzyme Activity Monitoring

The process of detecting enzyme levels in body fluids to assess cell damage.

Penicillin

An antibiotic that inhibits bacterial cell wall formation by targeting specific enzymes.

ACE Inhibitors

Drugs that prevent the synthesis of angiotensin-converting enzyme to lower blood pressure.

HIV Protease Inhibitors

Medications that interfere with the enzyme necessary for HIV replication.