Asparagine. Molecular model of the amino acid asparagine (C4.H8.N2.O3). It is a non-essential amino acid. It can be synthesised by the body and so does not need to come from the diet. Asparagine plays an important role in the folding of protein molecules into their secondary structures. Atoms are represented as spheres and are colour-coded: carbon (grey), hydrogen (white), nitrogen (blue) and oxygen (red).