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1e7q
From Proteopedia
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| - | [[Image:1e7q.jpg|left|200px]] | + | [[Image:1e7q.jpg|left|200px]] |
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| - | '''GDP 4-KETO-6-DEOXY-D-MANNOSE EPIMERASE REDUCTASE S107A''' | + | {{Structure |
| + | |PDB= 1e7q |SIZE=350|CAPTION= <scene name='initialview01'>1e7q</scene>, resolution 1.6Å | ||
| + | |SITE= <scene name='pdbsite=AC1:Nap+Binding+Site,+Residue+Ala107+Is+Mutat+The+Native+Bei+...'>AC1</scene> and <scene name='pdbsite=AC2:Uvw+Binding+Site+For+Chain+A'>AC2</scene> | ||
| + | |LIGAND= <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=NAP:NADP+NICOTINAMIDE-ADENINE-DINUCLEOTIDE+PHOSPHATE'>NAP</scene>, <scene name='pdbligand=UVW:ACETYLPHOSPHATE'>UVW</scene> and <scene name='pdbligand=TRS:2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL'>TRS</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''GDP 4-KETO-6-DEOXY-D-MANNOSE EPIMERASE REDUCTASE S107A''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1E7Q is a [ | + | 1E7Q is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1E7Q OCA]. |
==Reference== | ==Reference== | ||
| - | Probing the catalytic mechanism of GDP-4-keto-6-deoxy-d-mannose Epimerase/Reductase by kinetic and crystallographic characterization of site-specific mutants., Rosano C, Bisso A, Izzo G, Tonetti M, Sturla L, De Flora A, Bolognesi M, J Mol Biol. 2000 Oct 13;303(1):77-91. PMID:[http:// | + | Probing the catalytic mechanism of GDP-4-keto-6-deoxy-d-mannose Epimerase/Reductase by kinetic and crystallographic characterization of site-specific mutants., Rosano C, Bisso A, Izzo G, Tonetti M, Sturla L, De Flora A, Bolognesi M, J Mol Biol. 2000 Oct 13;303(1):77-91. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/11021971 11021971] |
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: sdr]] | [[Category: sdr]] | ||
| - | ''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 10:51:14 2008'' |
Revision as of 08:51, 20 March 2008
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| , resolution 1.6Å | |||||||
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| Sites: | and | ||||||
| Ligands: | , , and | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
GDP 4-KETO-6-DEOXY-D-MANNOSE EPIMERASE REDUCTASE S107A
Overview
GDP-4-keto-6-deoxy-d-mannose epimerase/reductase is a bifunctional enzyme responsible for the last step in the biosynthesis of GDP-l-fucose, the substrate of fucosyl transferases. Several cell-surface antigens, including the leukocyte Lewis system and cell-surface antigens in pathogenic bacteria, depend on the availability of GDP-l-fucose for their expression. Therefore, the enzyme is a potential target for therapy in pathological states depending on selectin-mediated cell-to-cell interactions. Previous crystallographic investigations have shown that GDP-4-keto-6-deoxy-d-mannose epimerase/reductase belongs to the short-chain dehydrogenase/reductase protein homology family. The enzyme active-site region is at the interface of an N-terminal NADPH-binding domain and a C-terminal domain, held to bind the substrate. The design, expression and functional characterization of seven site-specific mutant forms of GDP-4-keto-6-deoxy-d-mannose epimerase/reductase are reported here. In parallel, the crystal structures of the native holoenzyme and of three mutants (Ser107Ala, Tyr136Glu and Lys140Arg) have been investigated and refined at 1. 45-1.60 A resolution, based on synchrotron data (R-factors range between 12.6 % and 13.9 %). The refined protein models show that besides the active-site residues Ser107, Tyr136 and Lys140, whose mutations impair the overall enzymatic activity and may affect the coenzyme binding mode, side-chains capable of proton exchange, located around the expected substrate (GDP-4-keto-6-deoxy-d-mannose) binding pocket, are selectively required during the epimerization and reduction steps. Among these, Cys109 and His179 may play a primary role in proton exchange between the enzyme and the epimerization catalytic intermediates. Finally, the additional role of mutated active-site residues involved in substrate recognition and in enzyme stability has been analyzed.
About this Structure
1E7Q is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Probing the catalytic mechanism of GDP-4-keto-6-deoxy-d-mannose Epimerase/Reductase by kinetic and crystallographic characterization of site-specific mutants., Rosano C, Bisso A, Izzo G, Tonetti M, Sturla L, De Flora A, Bolognesi M, J Mol Biol. 2000 Oct 13;303(1):77-91. PMID:11021971
Page seeded by OCA on Thu Mar 20 10:51:14 2008
Categories: Escherichia coli | Single protein | Bolognesi, M. | Izzo, G. | Rosano, C. | NAP | SO4 | TRS | UVW | Epimerase/reductase | Red | Sdr
