Evolution and functional classification of mammalian copper amine oxidases.

Mammalian copper-containing amine oxidases (CAOs), encoded by four genes (AOC1-4) and catalyzing the oxidation of primary amines to aldehydes, regulate many biological processes and are linked to various diseases including inflammatory conditions and histamine intolerance. Despite the known differences in their substrate preferences, CAOs are currently classified based on their preference for either primary monoamines (EC 1.4.

Multivalent Interactions of Human Primary Amine Oxidase with the V and C22 Domains of Sialic Acid-Binding Immunoglobulin-Like Lectin-9 Regulate Its Binding and Amine Oxidase Activity.

Sialic acid-binding immunoglobulin-like lectin-9 (Siglec-9) on leukocyte surface is a counter-receptor for endothelial cell surface adhesin, human primary amine oxidase (hAOC3), a target protein for anti-inflammatory agents. This interaction can be used to detect inflammation and cancer in vivo, since the labeled peptides derived from the second C2 domain (C22) of Siglec-9 specifically bind to the inflammation-inducible hAOC3. As limited knowledge on the interaction between Siglec-9 and hAOC3 has hampered both hAOC3-targeted drug design and in vivo imaging applications, we have now produced and purified the extracellular region of Siglec-9 (Siglec-9-EC) consisting of the V, C21 and C22 domains, modeled its 3D structure and characterized the hAOC3-Siglec-9 interactions using biophysical methods and activity/inhibition assays.

Novel pyridazinone inhibitors for vascular adhesion protein-1 (VAP-1): old target-new inhibition mode.

Vascular adhesion protein-1 (VAP-1) is a primary amine oxidase and a drug target for inflammatory and vascular diseases. Despite extensive attempts to develop potent, specific, and reversible inhibitors of its enzyme activity, the task has proven challenging. Here we report the synthesis, inhibitory activity, and molecular binding mode of novel pyridazinone inhibitors, which show specificity for VAP-1 over monoamine and diamine oxidases.

Structural comparison of the active site channels in rodent and primate vascular adhesion protein-1.

In this study, we have made homology models of mouse, rat, and monkey vascular adhesion protein-1 (VAP-1) to reveal basis for the species-specific ligand recognition of VAP-1. Based on the structural comparisons, rodent VAP-1s have a narrower active site channel than primate VAP-1s. The variable residues in mouse and rat VAP-1, Phe447 from arm I and the polar residues from the first α-helix of the D3 domain together with C-terminal residues are likely to affect ligand recognition and binding.