1wmo

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spinqualitylabelsall models 1wmo, resolution 1.8Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Crystal structure of topaquinone-containing amine oxidase activated by nickel ion

Overview

The topa quinone (TPQ) cofactor of copper amine oxidase is generated by, copper-assisted self-processing of the precursor protein. Metal ion, specificity for TPQ biogenesis has been reinvestigated with the, recombinant phenylethylamine oxidase from Arthrobacter globiformis., Besides Cu2+ ion, some divalent metal ions such as Co2+, Ni2+, and Zn2+, were also bound to the metal site of the apoenzyme so tightly that they, were not replaced by excess Cu2+ ions added subsequently. Although these, noncupric metal ions could not initiate TPQ formation under the, atmospheric conditions, we observed slow spectral changes in the enzyme, bound with Co2+ or Ni2+ ion under the dioxygen-saturating conditions., Resonance Raman spectroscopy and titration with phenylhydrazine provided, unambiguous evidence for TPQ formation by Co2+ and Ni2+ ions. Steady-state, kinetic analysis showed that the enzymes activated by Co2+ and Ni2+ ions, were indistinguishable from the corresponding metal-substituted enzymes, prepared from the native copper enzyme (Kishishita, S., Okajima, T., Kim, M., Yamaguchi, H., Hirota, S., Suzuki, S., Kuroda, S., Tanizawa, K., and, Mure, M. (2003) J. Am. Chem. Soc. 125, 1041-1055). X-ray crystallographic, analysis has also revealed structural identity of the active sites of Co-, and Ni-activated enzymes with Cu-enzyme. Thus Cu2+ ion is not the sole, metal ion assisting TPQ formation. Co2+ and Ni2+ ions are also capable of, forming TPQ, though much less efficiently than Cu2+.

About this Structure

1WMO is a Single protein structure of sequence from Arthrobacter globiformis with NI as ligand. Active as Amine oxidase (copper-containing), with EC number 1.4.3.6 Full crystallographic information is available from OCA.

Reference

Reinvestigation of metal ion specificity for quinone cofactor biogenesis in bacterial copper amine oxidase., Okajima T, Kishishita S, Chiu YC, Murakawa T, Kim M, Yamaguchi H, Hirota S, Kuroda S, Tanizawa K, Biochemistry. 2005 Sep 13;44(36):12041-8. PMID:16142901

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