1. Biochemistry: Macromolecules Part 2
AP Biology
Biochemistry: Macromolecules
Part 2

2. Proteins

3. LE 5-UN78
a carbon
Amino
group
Carboxyl
group

4. Fig: 5.17a

5. Fig: 5.17b

6. Dehydration and Hydrolysis Reactions again
Short polymer
Unlinked monomer
Dehydration removes a water
molecule, forming a new bond
Longer polymer
Dehydration reaction in the synthesis of a polymer
Hydrolysis adds a water
molecule, breaking a bond
Hydrolysis of a polymer

7. Peptide Bonding

8. Primary (1’) sequence

9. Primary Structure is IMPORTANT

10. Sickle Cell and Oxygen transport
Normal hemoglobin
Sickle-cell hemoglobin
Primary
structure
Val
His
Leu
Thr
Pro
Glu
Glu
Primary
structure
Val
His
Leu
Thr
Pro
Val
Glu 1 2 3 4 5 6 7 1 2 3 4 5 6 7
Exposed
hydrophobic
region
Secondary
and tertiary
structures
Secondary
and tertiary
structures
b subunit
b subunit a a  
Quaternary
structure
Normal
hemoglobin
(top view)
Quaternary
structure
Sickle-cell
hemoglobin a   a
Function
Molecules do
not associate
with one
another; each
carries oxygen.
Function
Molecules
interact with
one another to
crystallize into
a fiber; capacity
to carry oxygen
is greatly reduced.

11. 2’ structure

12. 3’ Structure

13. 4’ Structure

14. Protein’s Natural Form

15. Denaturation of a protein

16. Chaperonin

17. Nitrogen Cycle and Proteins
N2 in atmosphere
Assimilation
Denitrifying
bacteria
NO3–
Nitrogen-fixing
bacteria in root
nodules of legumes
Decomposers
Nitrifying
bacteria
Ammonification
Nitrification
NH3
NH4+
NO2–
Nitrogen-fixing
soil bacteria
Nitrifying
bacteria