1w1r: Difference between revisions
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[[Image:1w1r.gif|left|200px]]<br /> | [[Image:1w1r.gif|left|200px]]<br /><applet load="1w1r" size="450" color="white" frame="true" align="right" spinBox="true" | ||
<applet load="1w1r" size="450" color="white" frame="true" align="right" spinBox="true" | |||
caption="1w1r, resolution 1.90Å" /> | caption="1w1r, resolution 1.90Å" /> | ||
'''PLANT CYTOKININ DEHYDROGENASE IN COMPLEX WITH TRANS-ZEATIN'''<br /> | '''PLANT CYTOKININ DEHYDROGENASE IN COMPLEX WITH TRANS-ZEATIN'''<br /> | ||
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==About this Structure== | ==About this Structure== | ||
1W1R is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Zea_mays Zea mays] with NAG, FAD and ZEA as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Cytokinin_dehydrogenase Cytokinin dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.5.99.12 1.5.99.12] | 1W1R is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Zea_mays Zea mays] with NAG, FAD and ZEA as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Cytokinin_dehydrogenase Cytokinin dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.5.99.12 1.5.99.12] Known structural/functional Site: <scene name='pdbsite=AC1:Nag Binding Site For Chain A'>AC1</scene>. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1W1R OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: signal]] | [[Category: signal]] | ||
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Dec 18 18:26:28 2007'' | ||
Revision as of 19:16, 18 December 2007
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PLANT CYTOKININ DEHYDROGENASE IN COMPLEX WITH TRANS-ZEATIN
OverviewOverview
Cytokinins form a diverse class of compounds that are essential for plant, growth. Cytokinin dehydrogenase has a major role in the control of the, levels of these plant hormones by catalysing their irreversible oxidation., The crystal structure of Zea mays cytokinin dehydrogenase displays the, same two-domain topology of the flavoenzymes of the vanillyl-alcohol, oxidase family but its active site cannot be related to that of any other, family member. The X-ray analysis reveals a bipartite architecture of the, catalytic centre, which consists of a funnel-shaped region on the protein, surface and an internal cavity lined by the flavin ring. A pore with, diameter of about 4A connects the two active-site regions. Snapshots of, two critical steps along the reaction cycle were obtained through the, structural analysis of the complexes with a slowly reacting substrate and, the reaction product, which correspond to the states immediately before, (Michaelis complex) and after (product complex) oxidation has taken place., The substrate displays a "plug-into-socket" binding mode that seals the, catalytic site and precisely positions the carbon atom undergoing, oxidation in close contact with the reactive locus of the flavin. A, polarising H-bond between the substrate amine group and an Asp-Glu pair, may facilitate oxidation. Substrate to product conversion results in small, atomic movements, which lead to a planar conformation of the reaction, product allowing double-bond conjugation. These features in the mechanism, of amine recognition and oxidation differ from those observed in other, flavin-dependent amine oxidases.
About this StructureAbout this Structure
1W1R is a Single protein structure of sequence from Zea mays with NAG, FAD and ZEA as ligands. Active as Cytokinin dehydrogenase, with EC number 1.5.99.12 Known structural/functional Site: . Full crystallographic information is available from OCA.
ReferenceReference
Structures of Michaelis and product complexes of plant cytokinin dehydrogenase: implications for flavoenzyme catalysis., Malito E, Coda A, Bilyeu KD, Fraaije MW, Mattevi A, J Mol Biol. 2004 Aug 27;341(5):1237-49. PMID:15321719
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