2ok4
From Proteopedia
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| - | [[Image:2ok4.jpg|left|200px]] | + | [[Image:2ok4.jpg|left|200px]] |
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| - | '''Crystal structure of aromatic amine dehydrogenase TTQ-phenylacetaldehyde adduct oxidized with ferricyanide''' | + | {{Structure |
| + | |PDB= 2ok4 |SIZE=350|CAPTION= <scene name='initialview01'>2ok4</scene>, resolution 1.45Å | ||
| + | |SITE= <scene name='pdbsite=AC1:Hy1+Binding+Site+For+Residue+H+2001'>AC1</scene> and <scene name='pdbsite=AC2:Hy1+Binding+Site+For+Residue+D+2002'>AC2</scene> | ||
| + | |LIGAND= <scene name='pdbligand=HY1:PHENYLACETALDEHYDE'>HY1</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Aralkylamine_dehydrogenase Aralkylamine dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.4.99.4 1.4.99.4] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''Crystal structure of aromatic amine dehydrogenase TTQ-phenylacetaldehyde adduct oxidized with ferricyanide''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 2OK4 is a [ | + | 2OK4 is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Alcaligenes_faecalis Alcaligenes faecalis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2OK4 OCA]. |
==Reference== | ==Reference== | ||
| - | New insights into the reductive half-reaction mechanism of aromatic amine dehydrogenase revealed by reaction with carbinolamine substrates., Roujeinikova A, Hothi P, Masgrau L, Sutcliffe MJ, Scrutton NS, Leys D, J Biol Chem. 2007 Aug 17;282(33):23766-77. Epub 2007 May 1. PMID:[http:// | + | New insights into the reductive half-reaction mechanism of aromatic amine dehydrogenase revealed by reaction with carbinolamine substrates., Roujeinikova A, Hothi P, Masgrau L, Sutcliffe MJ, Scrutton NS, Leys D, J Biol Chem. 2007 Aug 17;282(33):23766-77. Epub 2007 May 1. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17475620 17475620] |
[[Category: Alcaligenes faecalis]] | [[Category: Alcaligenes faecalis]] | ||
[[Category: Aralkylamine dehydrogenase]] | [[Category: Aralkylamine dehydrogenase]] | ||
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[[Category: ttq]] | [[Category: ttq]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 18:00:44 2008'' |
Revision as of 16:00, 20 March 2008
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| , resolution 1.45Å | |||||||
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| Sites: | and | ||||||
| Ligands: | |||||||
| Activity: | Aralkylamine dehydrogenase, with EC number 1.4.99.4 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of aromatic amine dehydrogenase TTQ-phenylacetaldehyde adduct oxidized with ferricyanide
Overview
Aromatic amine dehydrogenase uses a tryptophan tryptophylquinone (TTQ) cofactor to oxidatively deaminate primary aromatic amines. In the reductive half-reaction, a proton is transferred from the substrate C1 to betaAsp-128 O-2, in a reaction that proceeds by H-tunneling. Using solution studies, kinetic crystallography, and computational simulation we show that the mechanism of oxidation of aromatic carbinolamines is similar to amine oxidation, but that carbinolamine oxidation occurs at a substantially reduced rate. This has enabled us to determine for the first time the structure of the intermediate prior to the H-transfer/reduction step. The proton-betaAsp-128 O-2 distance is approximately 3.7A, in contrast to the distance of approximately 2.7A predicted for the intermediate formed with the corresponding primary amine substrate. This difference of approximately 1.0 A is due to an unexpected conformation of the substrate moiety, which is supported by molecular dynamic simulations and reflected in the approximately 10(7)-fold slower TTQ reduction rate with phenylaminoethanol compared with that with primary amines. A water molecule is observed near TTQ C-6 and is likely derived from the collapse of the preceding carbinolamine TTQ-adduct. We suggest this water molecule is involved in consecutive proton transfers following TTQ reduction, and is ultimately repositioned near the TTQ O-7 concomitant with protein rearrangement. For all carbinolamines tested, highly stable amide-TTQ adducts are formed following proton abstraction and TTQ reduction. Slow hydrolysis of the amide occurs after, rather than prior to, TTQ oxidation and leads ultimately to a carboxylic acid product.
About this Structure
2OK4 is a Protein complex structure of sequences from Alcaligenes faecalis. Full crystallographic information is available from OCA.
Reference
New insights into the reductive half-reaction mechanism of aromatic amine dehydrogenase revealed by reaction with carbinolamine substrates., Roujeinikova A, Hothi P, Masgrau L, Sutcliffe MJ, Scrutton NS, Leys D, J Biol Chem. 2007 Aug 17;282(33):23766-77. Epub 2007 May 1. PMID:17475620
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