- * Let's start with alanine, also written as Ala or A.
- Draw a general amino acid stick structure and replace the R with a line.
- Remind ourselves: what does the line represent? A methyl (CH3) group.
- Alanine is considered to be the simplest amino acid (even though glycine has a simpler R group) because its R group is large enough to give it some steric constraints, but small enough to prevent major changes in protein structure.
Amino Acids: Hydrophobic/Aliphatic
Hydrophobic
Alanine (Ala, A)
Valine (Val, V)
- Beta branching; branch at the beta carbon
Leucine (Leu, L)
- Branch on gamma carbon
Isoleucine (Ile, I)
- Beta branching
- Isomer of leucine (same formula, different arrangement of atoms)
Methionine (Met, M)
- Contains sulfur atom