5.4 Enzyme Active Sites and Chemical Catalysis

These flashcards cover key concepts related to enzyme function, active sites, and mechanisms of chemical catalysis as discussed in the lecture notes.

Enzymes

Biological catalysts that accelerate chemical reactions by stabilizing transition states and orienting substrates.

Active Site

The region on an enzyme where substrate molecules bind and undergo a chemical reaction.

Transition State

A high-energy state during a chemical reaction in which reactants are transformed into products.

Hydrophobic Channels

Structural features in enzymes that guide nonpolar substrates into the active site while restricting water access.

Acid-Base Catalysis

A mechanism where enzymes donate or accept protons to facilitate reactions, often involving ionizable side chains.

Covalent Catalysis

A mechanism involving the formation of a transient covalent bond between the enzyme and the substrate.

Metal-Ion Catalysis

A mechanism where metal ions in enzymes stabilize charges and orient substrates for reactions.

Gibbs Energy

The energy associated with a chemical reaction that can be used to determine the spontaneity of the reaction.

Transition State Analogs

Molecules that mimic the transition state and serve as potent inhibitors by binding tightly to enzymes.

pKa

The measure of the strength of an acid in solution, indicating the tendency of a functional group to either donate or accept a proton.