Enzymes, Nature’s Catalyst

1. Enzymes, Nature’s 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 enzyme substrate products Reaction (rxn) Pg. 166

4. Lock & Key Analogy Key fits lock-turns it—thus opening the door for rxn to proceed key Lock substrate enzyme

5. Example of Enzyme reaction Active site • Enzyme –sucrase • end with -ase • Substrate - sucrose • Products – glucose & fructose • Glucose + Fructose  Sucrose sucrase sucrose Glucose & Fructose reaction

6. Enzymes, Nature’s 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