Cleland nomenclature

Cle·land no·men·cla·ture

a system for representing the binding mechanisms of enzyme-catalyzed reactions; in this nomenclature, substrates are represented by the letters A, B, C, etc., whereas products are represented by P, Q, R, etc., enzyme by E, and modified forms of the enzyme by F, G, etc.; in addition, the number of substrates or products is represented by uni, bi, ter, etc.; thus, an aminotransferase reaction (for example, alanine transaminase) has a ping-pong bi-bi mechanism, and glutamine synthetase has a random ter-ter mechanism. See also entries under mechanism [W. Wallace Cleland]