Molecular structures for amino-acids:

 

Alanine (Ala): R / S

Aspartic acid (Asp): R / S

Valine (Val): R / S

Serine (Ser): R / S

Methionine (Met): R / S

Leucine (Leu): R / S

Glutamic acid (Glu): R / S

Lysine (Lys): R / S