1. PROTEINS (Polymers of Amino Acids)

2. 20 Amino Acids Grouped by properties of their side chains Polypeptide
Non-polar (hydrophobic)
Polar (hydrophilic)
Acidic (-COOH grp)
Basic (-NH2)
Polypeptide
Many amino acids
linked together

3. Types of Proteins Structural – ligaments, hair, horns, webs
Storage (energy) – seeds, egg whites
Transportation – blood & Facillitated Diffusion
Regulation – hormones: insulin & testosterone
Movement/Reaction – reflex, contraction
Immunology – antigens & antibodies
Enzymes – speed up rxns (digestion)

4. DENATURATION Protein loses its shape & no longer function Causes:
More shape changes, greater impact on its ability to function
Causes:
Temperature
pH (toxic chemicals)
Radiation
Example: Sickle Cell Anemia

5. MOLECULAR STRUCTURE
PRIMARY
Sequence of amino acids

6. MOLECULAR STRUCTURE Single (point) mutations can cause problems
Normal hemoglobin:
VAL – HIS – LEU – THR – PRO – GLU – GLU
Sickle Cell Hemo.:
VAL – HIS – LEU – THR – PRO – VAL – GLU

7. MOLECULAR STRUCTURE SECONDARY A.A. chain coil or fold due H-bonds
Alpha Helix: -- Pleated Sheets

8. MOLECULAR STRUCTURE TERTIARY 3-D shape
Globular – (round clusters – hemoglobin)
Fibrous – (long threads – collegen)
Hydrophobic interaction – nonpolar sections of molecule clump to middle of protein away from any possible sources of water

9. MOLECULAR STRUCTURE QUATERNARY
Interaction of multiple polypeptide chains

10. ENZYMES Substrate – substance being broken down
Active site – area where substrate/enzyme connect
Induced Fit – slight change of shape as enzyme & substrate join

11. Affects on Reaction Rates
Cofactors / coenzymes – an additional enzyme working on same substrate
Competitive Inhibitors –
block active site

12. Affects on Reaction Rates
Noncompetitive Inhibitors – changes shape of the enzyme without attaching to the active site
Allosteric regulation – attachment of another molecule which changes the shape of the enzyme

13. Metabolic Controls
Feedback Inhibition – the product of the reaction binds to the enzyme & prevents it from doing its job. Avoid excess production

14. Metabolic Controls
Cooperativity – (form allosteric regulation) when another molecule helps maintain shape of enzyme