Module 5

Enzymes

Proteins that accelerate, regulate, and coordinate chemical reactions in biological systems.

Vitalism

The belief that living organisms are fundamentally different from inanimate objects due to the presence of a non-physical element.

Coenzymes

Complex organic molecules or vitamins required for enzyme activity.

Apoenzyme

The inactive form of an enzyme when it is not bound to its cofactor.

Holoenzyme

The active form of an enzyme when it is bound to its cofactor.

Catalyst

Substance that lowers the activation energy required for a reaction to proceed.

Specificity

The property of enzymes to catalyze a particular reaction without side reactions.

Transition State

The high-energy state during a reaction where substrates are converted into products.

Michaelis-Menten Kinetics

A model that describes the rate of enzyme-catalyzed reactions with substrate concentration.

kcat

Turnover number; the number of substrate molecules converted to product per enzyme molecule per unit time under saturating conditions.

Allosteric Regulation

The regulation of enzyme activity through binding of molecules at sites other than the active site.

Endergonic Reaction

A reaction that requires an input of free energy to occur.

Exergonic Reaction

A spontaneous reaction that releases free energy.

Serine Proteases

Digestive enzymes that cleave peptide bonds in proteins, activated as zymogens.

Enzyme Inhibition

The process by which an inhibitor molecule decreases or eliminates the activity of an enzyme.

Covalent Modification

The attachment of a modifying group to a protein, affecting its activity.

Glycogen Synthase

An enzyme that produces glycogen from glucose.

Glycogen Phosphorylase

An enzyme that breaks down glycogen into glucose.

Cooperative Activation

A phenomenon where binding of a substrate enhances the activity of an enzyme.

Serine Residues

Amino acids that often play a role in the catalytic mechanism of enzymes.

Substrate Concentration (S)

The amount of substrate available for enzyme reactions, impacting the rate of reaction.