1pj3
From Proteopedia
(New page: 200px<br /> <applet load="1pj3" size="450" color="white" frame="true" align="right" spinBox="true" caption="1pj3, resolution 2.10Å" /> '''Crystal structure o...) |
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- | [[Image:1pj3.gif|left|200px]]<br /> | + | [[Image:1pj3.gif|left|200px]]<br /><applet load="1pj3" size="350" color="white" frame="true" align="right" spinBox="true" |
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caption="1pj3, resolution 2.10Å" /> | caption="1pj3, resolution 2.10Å" /> | ||
'''Crystal structure of human mitochondrial NAD(P)+-dependent malic enzyme in a pentary complex with natural substrate pyruvate, cofactor NAD+, Mn++, and allosteric activator fumarate.'''<br /> | '''Crystal structure of human mitochondrial NAD(P)+-dependent malic enzyme in a pentary complex with natural substrate pyruvate, cofactor NAD+, Mn++, and allosteric activator fumarate.'''<br /> | ||
==Overview== | ==Overview== | ||
- | Malic enzymes catalyze the oxidative decarboxylation of L-malate to | + | Malic enzymes catalyze the oxidative decarboxylation of L-malate to pyruvate and CO(2) with the reduction of the NAD(P)(+) cofactor in the presence of divalent cations. We report the crystal structures at up to 2.1 A resolution of human mitochondrial NAD(P)(+)-dependent malic enzyme in different pentary complexes with the natural substrate malate or pyruvate, the dinucleotide cofactor NAD(+) or NADH, the divalent cation Mn(2+), and the allosteric activator fumarate. Malate is bound deep in the active site, providing two ligands for the cation, and its C4 carboxylate group is out of plane with the C1-C2-C3 atoms, facilitating decarboxylation. The divalent cation is positioned optimally to catalyze the entire reaction. Lys183 is the general base for the oxidation step, extracting the proton from the C2 hydroxyl of malate. Tyr112-Lys183 functions as the general acid-base pair to catalyze the tautomerization of the enolpyruvate product from decarboxylation to pyruvate. |
==Disease== | ==Disease== | ||
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==About this Structure== | ==About this Structure== | ||
- | 1PJ3 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with MN, PYR, NAD and FUM as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Malate_dehydrogenase_(decarboxylating) Malate dehydrogenase (decarboxylating)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.39 1.1.1.39] Full crystallographic information is available from [http:// | + | 1PJ3 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=MN:'>MN</scene>, <scene name='pdbligand=PYR:'>PYR</scene>, <scene name='pdbligand=NAD:'>NAD</scene> and <scene name='pdbligand=FUM:'>FUM</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Malate_dehydrogenase_(decarboxylating) Malate dehydrogenase (decarboxylating)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.39 1.1.1.39] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PJ3 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: oxidative decarboxylase]] | [[Category: oxidative decarboxylase]] | ||
- | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:29:18 2008'' |
Revision as of 12:29, 21 February 2008
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Crystal structure of human mitochondrial NAD(P)+-dependent malic enzyme in a pentary complex with natural substrate pyruvate, cofactor NAD+, Mn++, and allosteric activator fumarate.
Contents |
Overview
Malic enzymes catalyze the oxidative decarboxylation of L-malate to pyruvate and CO(2) with the reduction of the NAD(P)(+) cofactor in the presence of divalent cations. We report the crystal structures at up to 2.1 A resolution of human mitochondrial NAD(P)(+)-dependent malic enzyme in different pentary complexes with the natural substrate malate or pyruvate, the dinucleotide cofactor NAD(+) or NADH, the divalent cation Mn(2+), and the allosteric activator fumarate. Malate is bound deep in the active site, providing two ligands for the cation, and its C4 carboxylate group is out of plane with the C1-C2-C3 atoms, facilitating decarboxylation. The divalent cation is positioned optimally to catalyze the entire reaction. Lys183 is the general base for the oxidation step, extracting the proton from the C2 hydroxyl of malate. Tyr112-Lys183 functions as the general acid-base pair to catalyze the tautomerization of the enolpyruvate product from decarboxylation to pyruvate.
Disease
Known disease associated with this structure: Epilepsy, idopathic generalized, susceptibility to OMIM:[154270]
About this Structure
1PJ3 is a Single protein structure of sequence from Homo sapiens with , , and as ligands. Active as Malate dehydrogenase (decarboxylating), with EC number 1.1.1.39 Full crystallographic information is available from OCA.
Reference
Crystal structures of substrate complexes of malic enzyme and insights into the catalytic mechanism., Tao X, Yang Z, Tong L, Structure. 2003 Sep;11(9):1141-50. PMID:12962632
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