| Aliphatic R groups are nonpolar and hydrophobic.
Hydrophobicity increases with increasing number of C atoms in the
hydrocarbon chain. Although these amino acids prefer to remain
inside protein molecules, alanine and glycine are ambivalent, meaning
that they can be inside or outside the protein molecule. Glycine has
such a small side chain that it does not have much effect on the hydrophobic
interactions.
The structures below are shown in the ionization state that predominates
at pH 7.
|
More hydrophobic 
