Amino acids link together by peptide bonds to form peptide chains. They further undergo conformational changes to form functional proteins of interest. Proteins are macromolecules that play an important role in the cell.
Alanine and valine are aliphatic hydrophobic amino acids. When trying to synthesize a protein consisting of alternate L-alanine and L-valine residues, the following problems may arise:
The amino acids could link together via peptide bonds to form the primary structure. But the chain would not undergo secondary structure formation while consisting of only aliphatic hydrophobic chains. To form secondary and further conformational structures, other amino acids with charged and hydrophilic groups are essential.