title: Characterization of a model compound for the lysine tyrosylquinone cofactor of lysyl oxidase.
abstract: We characterized a model compound for the lysine tyrosylquinone (LTQ) cofactor of lysyl oxidase which is one of the mammalian copper-dependent amine oxidases. The model compound, 4-butylamino-5-methyl-o-quinone, was prepared from n-butylamine and 4-methylcatechol by the oxidation with sodium iodate and characterized by spectroscopic analyses. The absorption maximum at 494 nm is consistent with that of lysyl oxidase. The model compound was capable of deaminating benzylamine to benzaldehyde at 37 degrees C in buffered aqueous acetonitrile. The aldehyde production was markedly elevated in the presence of the Cu(II)-EDTA complex but inhibited by free Cu(II). The catalytic cycle was observed at pH 10 in the presence of Cu(II), and the pH activity profile showed a broad optimum at about pH 9.0. In the presence of beta-aminopropionitrile and upon deoxygenation with N2 aldelyde, production was decreased. The important features of the reaction were consistent with the enzymatic reaction.
authors.affiliation: Department of Applied Bioorganic Chemistry, Division of Life Science, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aobaku, Sendai, 981-8555, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Akagawa
authors.forename: K
authors.initials: K
authors.lastname: Suyama
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000629:Aminopropionitrile / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D001547:Benzaldehydes / Q000737:chemistry; D016227:Benzoquinones / Q000737:chemistry*; D001596:Benzylamines / Q000737:chemistry; D002082:Butylamines / Q000737:chemistry; D002396:Catechols / Q000737:chemistry; D003300:Copper / Q000378:metabolism; D004492:Edetic Acid / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007452:Iodates / Q000737:chemistry; D008239:Lysine / Q000031:analogs & derivatives / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D010100:Oxygen / Q000378:metabolism; D008249:Protein-Lysine 6-Oxidase / Q000737:chemistry* / Q000378:metabolism; D011809:Quinones / Q000737:chemistry*; D013053:Spectrophotometry; D013997:Time Factors; D014466:Ultraviolet Rays
chemical_list: C423006:4-butylamino-5-methyl-2-quinone; D000097:Acetonitriles; D000975:Antioxidants; D001547:Benzaldehydes; D016227:Benzoquinones; D001596:Benzylamines; D002082:Butylamines; D002396:Catechols; D007452:Iodates; D011809:Quinones; C100796:lysine tyrosylquinone; C018599:4-methylcatechol; D000629:Aminopropionitrile; D003300:Copper; D004492:Edetic Acid; C030796:benzylamine; D008249:Protein-Lysine 6-Oxidase; D008239:Lysine; D010100:Oxygen; C032175:benzaldehyde; C032285:sodium iodate; C032159:acetonitrile