Each monomer consists of an active site that includes a Cu(II) atom, coordinated by three histidine residues, as well as 2,4,5-trihydroxyphenylalanine quinone (TPQ), a crucial cofactor.
The DNA sequence encodes a polypeptide of 417 amino acids, the first 21 residues of which constitute a signal peptide,[6] with a weight of approximately 32 kDa.
Molecular oxygen and the copper ion are utilized to reoxidize the cofactor, producing hydrogen peroxide as a side product.
[14] Lysyl oxidase is an extracellular copper-dependent enzyme that catalyzes formation of aldehydes from lysine residues in collagen and elastin precursors.
[18] This resulted in lathyrism, characterized by poor bone formation and strength, hyperextensible skin, weak ligaments, and increased occurrence of aortic aneurysms.
[19] Developmentally, reduced lysyl oxidase activity have been implicated in Menkes disease and occipital horn syndrome, two X-linked recessive disorders characterized by a mutation in a gene coding for a protein involved in copper transport.
[24] LOX expression was also detected in megakaryocytes, or bone marrow cells responsible for the production of platelets.
In a rodent model of breast cancer, a small-molecule or antibody inhibitors of LOX abolished metastasis.
[26] In cells lacking TGF-β receptors, a deficiency that is characteristic of lung cancer, lysyl oxidase is found in high concentrations.
[27] Lysyl oxidase has been newly implicated in tumor angiogenesis, or blood vessel formation, both in vivo and in vitro.