In practice, the term is mainly used more specifically to indicate that non-carbon atoms have replaced carbon in the backbone of the molecular structure. Typical heteroatoms are nitrogen (N), oxygen (O), sulfur (S), phosphorus (P), chlorine (Cl), bromine (Br), and iodine (I),[2][3] as well as the metals lithium (Li) and magnesium (Mg).
Proteins
It can also be used with highly specific meanings in specialised contexts. In the description of protein structure, in particular in the Protein Data Bank file format, a heteroatom record (HETATM) describes an atom as belonging to a small molecule cofactor rather than being part of a biopolymer chain.[4]
^Housecroft, Catherine E.; Constable, Edwin C. (2006). Chemistry - An introduction to organic, inorganic and physical chemistry (3rd ed.). Prentice Hall. p. 945. ISBN978-0131275676.
^Senda, Y. (2002). "Role of the heteroatom on stereoselectivity in the complex metal hydride reduction of six-membered cyclic ketones". Chirality. 14 (2–3): 110–120. doi:10.1002/chir.10051. PMID11835553.
^Walling, Cheves (1968). "The Role of Heteroatoms in Oxidation". In Mayo, Frank R. (ed.). Oxidation of Organic Compounds. Advances in Chemistry. Vol. 75. pp. 166–173. doi:10.1021/ba-1968-0075.ch013. ISBN9780841200760.