Structure of Active Site

How is enzyme-function related to its structure

Enzyme function is tied to the structure of the active site, enzyme - substrate specificity and environmental factors

What is the active site

small region on an enzyme where the substrate binds, formed by a specific sequence of amino acids

What determines the specificity of an active site

by the enzyme’s amino acid sequence and 3D folding

2 Key features that allow an active site to interact with a substrate

Shape complementarity

Chemical compatibility

Shape complementarity

The active site’s shape matches the substrate.

Chemical compatibility

The active site contains amino acids with specific properties that interact with the substrate.

2 Models of enzyme-substrate interactions

Lock and Key model

Induced fit model

Lock and Key model

active site has a rigid shape that perfectly matches the substrate,

Induced fit model

Active site is flexible and adjusts its shape to fit the substrate more snugly upon binding

How does induced fit model enhance catalysis

The conformational change in the active site helps destabilize the substrate bonds, lowering the activation energy required for the reaction

What is denaturation

process by which 3D structure of an enzyme is altered, leading to the loss of its function

Causes of enzyme denaturation

High temperature

Extreme pH

Chemical agents