Enzymes, Nature’s Catalyst

1
Enzymes, Natures Catalyst

• Lecture 2

Proteins ? amino acids ? nucleotides
All enzymes are proteins, but not all proteins
are enzymes
2
Where are enzymes used?

• Foods baked goods, brewing, coffee, ice cream,
  milk, cheese, meats
• Non-Food Detergent, leather, photography,
  environment, paper, rubber
• Disease/Disorders myocardial infarction, liver
  disease, muscle diseases

3
ENZYMES
Active site

• Enzymes enables molecules, called substrates, to
  undergo a chemical change to form new substances,
  called products.
• Substrates, a molecule on which an enzyme acts on
• Active site, region on which the substrate binds

substrate
enzyme
products
Reaction (rxn)
Pg. 166
4
Lock Key Analogy
Key fits lock-turns itthus opening the door for
rxn to proceed
key
Lock
substrate
enzyme
5
Example of Enzyme reaction

• Enzyme sucrase
• end with -ase
• Substrate - sucrose
• Products glucose fructose
• Glucose Fructose ? Sucrose

Active site
sucrose
sucrase
Glucose Fructose
reaction
6
Enzymes, Natures Catalyst

• Catalyst promotes a reaction between other
  chemicals by reducing the energy required to
  activate a reaction
• Eg. Enzymes, Temperature, pH, salt concentrations

7
Enzyme Activation Vs. Inhibition
Normal substrate
Competitive Inhibitors Competes with normal
substrate, for active site
Slow down or stops reaction
8
Temperature Effects

• Most animal enzymes rapidly become denatured at
  temps above 40degC

9
pH Effects

• Enzymes are affected by changes in pH
• Optimum pH is the most favorable pH where an
  enzyme is most active

10
So

• All proteins are enzymes, but not all enzymes are
  proteins
• NO!!!
• All enzymes are proteins, but not all proteins
  are enzymes