Before the development of the EC number system, enzymes were named in an arbitrary fashion, and names like
old yellow enzyme and
malic enzyme that give little or no clue as to what reaction was catalyzed were in common use. Most of these names have fallen into disuse, though a few, especially proteolytic enzymes with very low specificity, such as
pepsin and
papain, are still used, as rational classification on the basis of specificity has been very difficult. By the 1950s the chaos was becoming intolerable, and after Hoffman-Ostenhof and Dixon and Webb had proposed somewhat similar schemes for classifying enzyme-catalyzed reactions, the International Congress of Biochemistry in
Brussels set up the Commission on Enzymes under the chairmanship of
Malcolm Dixon in 1955. The first version was published in 1961, and the Enzyme Commission was dissolved at that time, though its name lives on in the term
EC Number. The current sixth edition, published by the
International Union of Biochemistry and Molecular Biology in 1992 as the last version published as a printed book, contains 3196 different enzymes. Supplements 1-4 were published 1993–1999. Subsequent supplements have been published electronically, at the website of the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology. == See also ==