Heteroatom This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Heteroatom".
In the nomenclature of organic chemistry, a heteroatom (from Ancient Greek heteros, different, + atomos) is any atom that is not carbon or hydrogen. It is typically, but not exclusively, nitrogen, oxygen, sulfur, phosphorus, boron, chlorine, bromine, or iodine.
In the description of protein structure, particularly in the now-deprecated Protein Data Bank file format, a heteroatom record (HETATM) describes an atom belonging to a small molecule cofactor rather than to part of a biopolymer chain.
