Enzymes

1. Enzymes

2. Enzymes • Most Enzymes end with the letters - ASE • Enzymes are substrate specific….. Examples: • Maltase can only breakdown Maltose • Sucrase can only breakdown Sucrose • Amylase can only breakdown Amylose

3. Enzymes • The efficiency of Enzymes is affected by: - pH shifts: pepsinogen is only activated when stomach acids lower the pH - Heat: denatures enzymes

4. Allosteric Enzymes • Have two types of binding sites…. One for the substrate and one for the allosteric effector. Two types of Allosteric Effectors • Allosteric Activator – binds to the enzyme and changes its shape to induces a reaction. 2. Allosteric Inhibitor – binds to the enzyme and induces inactivity

5. Allosteric Enzymes

6. Competitive Inhibition An enzyme mimics the substrate and occupies the active site preventing a reaction.

7. Noncompetitor Inhibitor Prevents enzyme reactions by binding to the enzyme at locations other than the active site.

8. Cooperativity • Occurs when an enzyme becomes receptive to additional substrate molecules after one substrate molecule attaches to an active site. • Example: Hemoglobin…… its binding capacity to additional oxygen molecules increases after the first oxygen fills the active site.

9. Cooperativity