Amino Acid Structure
We divide amino acids into four general categories (with two special cases).
- 1. Hydrophobic, which have nonpolar side chains that are usually aliphatic. Aliphatic means the side chains they have only have carbon and hydrogen atoms in their R groups (and no resonance).
- 2. Aromatic, which have one or more aromatic rings in the side chains.
- 3. Polar, which have polar, uncharged side chains.
- 4. Charged, which have either positively or negatively charged side chains
- 5. And the special cases: glycine (its R group is a hydrogen atom), and proline
- 20 amino acids coded for in our genome.
- General structure = Central alpha carbon bound to: Hydrogen atom, Carboxylic acid group, Amino group, Variable R Group (differentiates the AA).