1. Macromolecules
Part 2
Unit 1
Chapter 5

2. Proteins Most structurally sophisticated molecules Structure:
consists of 1+ polypeptides folded into 3D shape
monomer = amino acids
polymer = polypeptide

3. Protein Functions Involved in almost everything: Enzymes
Defense (antibodies)
Storage (Casein in milk, ovalbumin in egg whites)
Transport (hemoglobin)
Hormonal (insulin)
Receptor (nerve cells)
Contractile and motor (muscle)
Structural (Keratin, collagen)

4. Four Levels of Protein Structure
Primary Structure
amino acid sequence determined by DNA
20 different amino acids
Linked by peptide bonds

5. Secondary Structure Folding along short sections of polypeptide
Shape from H bonds
Types:
Alpha helix
Beta pleated sheet

6. Tertiary Structure determined by interactions between side chains
Types:
hydrophobic & hydrophilic interactions
H bonds
ionic bonds
disulfide bridges

7. Quaternary Structure Joins together more than 1 polypeptide chain
a functional protein

8. Four Levels of Protein folding

9. Chaperonin proteins Guide protein folding
Keep new polypeptide separated from other things in cytoplasm while spontaneously folding

10. Denaturation Disrupt 3D structurepH
salt
temperature
disrupts H bonds, ionic bonds & disulfide bridges

11. Nucleic Acids Store and transmit hereditary info.
Nucleotides: Pentose, nitrogen base, phosphate group
DNA and RNA
Watson and Crick

12. Pairing of nucleotides
Nucleotides bond between DNA strands
H bonds hold bases together
A :: T
2 H bonds
G :: C
3 H bonds