Lysyl Oxidase And Lysyl Oxidase-Like Enzymes

Lysyl oxidase (LOX) and its four congeners, lysyl oxidase-like 1 (LOXL1), -2, -3, and -4, have received much investigative attention in recent years. LOX itself, is the prototypic form of these amine oxidase enzymes. LOX has long been considered to function exclusively as the enzyme that oxidizes peptidyl lysine in its collagen and elastin substrates, thereby initiating formation of the covalent cross-linkages that stabilize these fibrous proteins. This view has been greatly expanded in light of the revelations that LOX can function both as an anti-oncogenic agent and as an enhancer of malignancy in selected cancerous conditions. Evidence is also accumulating that points to the roles of specific LOXL members of this family in disease and in biological homeostasis. This chapter reviews structural and catalytic properties as well as the roles in biology of these amine oxidases and presents a computer-generated predicted 3D protein structure of LOX.