2ji8: Difference between revisions
No edit summary |
No edit summary |
||
| Line 5: | Line 5: | ||
==Overview== | ==Overview== | ||
Despite more than five decades of extensive studies of thiamin diphosphate, (ThDP) enzymes, there remain many uncertainties as to how these enzymes, achieve their rate enhancements. Here, we present a clear picture of, catalysis for the simple nonoxidative decarboxylase, oxalyl-coenzyme A, (CoA) decarboxylase, based on crystallographic snapshots along the, catalytic cycle and kinetic data on active site mutants. First, we provide, crystallographic evidence that, upon binding of oxalyl-CoA, the C-terminal, 13 residues fold over the substrate, aligning the substrate alpha-carbon, for attack by the ThDP-C2 atom. The second structure presented shows a, covalent reaction intermediate after decarboxylation, interpreted as being, nonplanar. Finally, the structure of a product complex is . | Despite more than five decades of extensive studies of thiamin diphosphate, (ThDP) enzymes, there remain many uncertainties as to how these enzymes, achieve their rate enhancements. Here, we present a clear picture of, catalysis for the simple nonoxidative decarboxylase, oxalyl-coenzyme A, (CoA) decarboxylase, based on crystallographic snapshots along the, catalytic cycle and kinetic data on active site mutants. First, we provide, crystallographic evidence that, upon binding of oxalyl-CoA, the C-terminal, 13 residues fold over the substrate, aligning the substrate alpha-carbon, for attack by the ThDP-C2 atom. The second structure presented shows a, covalent reaction intermediate after decarboxylation, interpreted as being, nonplanar. Finally, the structure of a product complex is presented. In, accordance with mutagenesis data, no side chains of the enzyme are implied, to directly participate in proton transfer except the glutamic acid, (Glu-56), which promotes formation of the 1',4'-iminopyrimidine tautomer, of ThDP needed for activation. | ||
==About this Structure== | ==About this Structure== | ||
2JI8 is a | 2JI8 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Oxalobacter_formigenes Oxalobacter formigenes] with MG, TPP, ADP, FYN and PGE as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Oxalyl-CoA_decarboxylase Oxalyl-CoA decarboxylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.1.8 4.1.1.8] Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2JI8 OCA]. | ||
==Reference== | ==Reference== | ||
| Line 36: | Line 36: | ||
[[Category: thiamine pyrophosphate]] | [[Category: thiamine pyrophosphate]] | ||
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 13:30:47 2007'' | ||
Revision as of 14:25, 5 November 2007
|
X-RAY STRUCTURE OF OXALYL-COA DECARBOXYLASE IN COMPLEX WITH FORMYL-COA
OverviewOverview
Despite more than five decades of extensive studies of thiamin diphosphate, (ThDP) enzymes, there remain many uncertainties as to how these enzymes, achieve their rate enhancements. Here, we present a clear picture of, catalysis for the simple nonoxidative decarboxylase, oxalyl-coenzyme A, (CoA) decarboxylase, based on crystallographic snapshots along the, catalytic cycle and kinetic data on active site mutants. First, we provide, crystallographic evidence that, upon binding of oxalyl-CoA, the C-terminal, 13 residues fold over the substrate, aligning the substrate alpha-carbon, for attack by the ThDP-C2 atom. The second structure presented shows a, covalent reaction intermediate after decarboxylation, interpreted as being, nonplanar. Finally, the structure of a product complex is presented. In, accordance with mutagenesis data, no side chains of the enzyme are implied, to directly participate in proton transfer except the glutamic acid, (Glu-56), which promotes formation of the 1',4'-iminopyrimidine tautomer, of ThDP needed for activation.
About this StructureAbout this Structure
2JI8 is a Single protein structure of sequence from Oxalobacter formigenes with MG, TPP, ADP, FYN and PGE as ligands. Active as Oxalyl-CoA decarboxylase, with EC number 4.1.1.8 Structure known Active Site: AC1. Full crystallographic information is available from OCA.
ReferenceReference
Crystallographic snapshots of oxalyl-CoA decarboxylase give insights into catalysis by nonoxidative ThDP-dependent decarboxylases., Berthold CL, Toyota CG, Moussatche P, Wood MD, Leeper F, Richards NG, Lindqvist Y, Structure. 2007 Jul;15(7):853-61. PMID:17637344
Page seeded by OCA on Mon Nov 5 13:30:47 2007
Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)
OCA- Pages with broken file links
- Oxalobacter formigenes
- Oxalyl-CoA decarboxylase
- Single protein
- Berthold, C.L.
- Leeper, F.
- Lindqvist, Y.
- Moussatche, P.
- Richards, N.G.J.
- Toyota, C.G.
- Wood, M.D.
- ADP
- FYN
- MG
- PGE
- TPP
- Decarboxylase
- Flavoprotein
- Lyase
- Non- oxidative decarboxylase
- Oxalate degradation
- Product complex
- Thiamin diphosphate-dependent
- Thiamine pyrophosphate