Glutamine. Molecular model of the amino acid glutamine. Its chemical formula is C4.H10.N2.O3. Atoms are represented as spheres and are colour- coded: carbon (blue), hydrogen (gold), oxygen (red) and nitrogen (dark blue). Amino acids are the building blocks of proteins. Glutamine is a semi-essential amino acid. It can be synthesised by the body, but those who are chronically ill or injured do need to obtain it from their food to regain their health. It is found in animal products and in cabbage, beetroot, legumes, spinach and parsley. Glutamine plays an important role in the synthesis of DNA (deoxyribonucleic acid) and proteins. It also is a precursor for rapidly dividing immune cells, thus aiding in immune function, and maintains kidney function.