1av4
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CRYSTAL STRUCTURES OF THE COPPER-CONTAINING AMINE OXIDASE FROM ARTHROBACTER GLOBIFORMIS IN THE HOLO-AND APO-FORMS: IMPLICATIONS FOR THE BIOGENESIS OF TOPA QUINONE
OverviewOverview
The crystal structures of the copper enzyme phenylethylamine oxidase from, the Gram-positive bacterium Arthrobacter globiformis (AGAO) have been, determined and refined for three forms of the enzyme: the holoenzyme in, its active form (at 2.2 A resolution), the holoenzyme in an inactive form, (at 2.8 A resolution), and the apoenzyme (at 2.2 A resolution). The, holoenzyme has a topaquinone (TPQ) cofactor formed from the apoenzyme by, the post-translational modification of a tyrosine residue in the presence, of Cu2+. Significant differences between the three forms of AGAO are, limited to the active site. The polypeptide fold is closely similar to, those of the amine oxidases from Escherichia coli [Parsons, M. R., et al., (1995) Structure 3, 1171-1184] and pea seedlings [Kumar, V., et al. (1996), Structure 4, 943-955]. In the active form of holo-AGAO, the active-site Cu, atom is coordinated by three His residues and two water molecules in an, approximately square-pyramidal arrangement. In the inactive form, the Cu, atom is coordinated by the same three His residues and by the phenolic, oxygen of the TPQ, the geometry being quasi-trigonal-pyramidal. There is, evidence of disorder in the crystals of both forms of holo-AGAO. As a, result, only the position of the aromatic group of the TPQ cofactor, but, not its orientation about the Cbeta-Cgamma bond, is determined, unequivocally. In apo-AGAO, electron density consistent with an unmodified, Tyr occurs at a position close to that of the TPQ in the inactive, holo-AGAO. This observation has implications for the biogenesis of TPQ., Two features which have not been described previously in amine oxidase, structures are a channel from the molecular surface to the active site and, a solvent-filled cavity at the major interface between the two subunits of, the dimer.
About this StructureAbout this Structure
1AV4 is a Single protein structure of sequence from Arthrobacter globiformis with CU as ligand. Active as Amine oxidase (copper-containing), with EC number 1.4.3.6 Full crystallographic information is available from OCA.
ReferenceReference
Crystal structures of the copper-containing amine oxidase from Arthrobacter globiformis in the holo and apo forms: implications for the biogenesis of topaquinone., Wilce MC, Dooley DM, Freeman HC, Guss JM, Matsunami H, McIntire WS, Ruggiero CE, Tanizawa K, Yamaguchi H, Biochemistry. 1997 Dec 23;36(51):16116-33. PMID:9405045
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