1PBY

Structure of the Phenylhydrazine Adduct of the Quinohemoprotein Amine Dehydrogenase from Paracoccus denitrificans at 1.7 A Resolution

Summary for 1PBY

• Entry DOI: 10.2210/pdb1pby/pdb
• Related: 1JJU
• Descriptor: quinohemoprotein amine dehydrogenase 60 kDa subunit, quinohemoprotein amine dehydrogenase 40 kDa subunit, quinohemoprotein amine dehydrogenase 9 kDa subunit, ... (6 entities in total)
• Functional Keywords: quinohemoprotein, amine dehydrogenase, oxidoreductase
• Biological source: Paracoccus denitrificans; More
• Total number of polymer chains: 3
• Total formula weight: 100110.74

Authors

Datta, S.,Ikeda, T.,Kano, K.,Mathews, F.S. (deposition date: 2003-05-15, release date: 2003-09-02, Last modification date: 2023-08-16)

Primary citation

Datta, S.,Ikeda, T.,Kano, K.,Mathews, F.S.
Structure of the phenylhydrazine adduct of the quinohemoprotein amine dehydrogenase from Paracoccus denitrificans at 1.7 A resolution.
Acta Crystallogr.,Sect.D, 59:1551-1556, 2003

PubMed Abstract: The 109 kDa quinohemoprotein amine dehydrogenase (QHNDH) from Paracoccus denitrificans contains a novel redox cofactor, cysteine tryptophylquinone (CTQ). This cofactor is derived from a pair of gene-encoded amino acids by post-translational modification and was previously identified and characterized within an 82-residue subunit by chemical methods and crystallographic analysis at 2.05 A resolution. It contains an orthoquinone moiety bound to the indole ring and catalyzes the oxidation of aliphatic and aromatic amines through formation of a Schiff-base intermediate involving one of the quinone O atoms. This paper reports the structural analysis of the complex of QHNDH with the enzyme inhibitor phenylhydrazine determined at 1.70 A resolution. The phenylhydrazone product is attached to the C6 position, identifying the O6 atom of CTQ as the site of Schiff-base formation as postulated by analogy to another amine-oxidizing enzyme, methylamine dehydrogenase. Furthermore, the inner N atom closest to the phenyl ring of phenylhydrazine forms a hydrogen bond to gammaAsp33 in the complex, lending support to the hypothesis that this residue serves as the active-site base for proton abstraction during catalysis.

PubMed: 12925784
DOI: 10.1107/S090744490301429X

Experimental method

X-RAY DIFFRACTION (1.7 Å)