Catalytic Properties and the Role of Copper in Bovine and Lentil Seedling Copper/Quinone‐Containing Amine Oxidases: Controversial Opinions

Abstract In this microreview, the differences in the catalytic cycle of two copper/quinone‐containing amine oxidases, one from lentil seedlings, representative of plant enzymes, and the other from bovine serum, typical of mammalian enzymes, are discussed. Although both enzymes are involved in the control of the levels of mono‐, di‐, and polyamines, and contain the same organic cofactor, the quinone of 2,4,5‐trihydroxyphenylalanine, known as TOPA or TPQ, lentil amine oxidase operates in a different way and with a much higher catalytic activity than the bovine serum enzyme. The role of copper in the two enzymes is also discussed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)