1wdm
From Proteopedia
(New page: 200px<br /><applet load="1wdm" size="450" color="white" frame="true" align="right" spinBox="true" caption="1wdm, resolution 3.8Å" /> '''fatty acid beta-oxida...) |
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| - | [[Image:1wdm.gif|left|200px]]<br /><applet load="1wdm" size=" | + | [[Image:1wdm.gif|left|200px]]<br /><applet load="1wdm" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1wdm, resolution 3.8Å" /> | caption="1wdm, resolution 3.8Å" /> | ||
'''fatty acid beta-oxidation multienzyme complex from Pseudomonas fragi, form I (native3)'''<br /> | '''fatty acid beta-oxidation multienzyme complex from Pseudomonas fragi, form I (native3)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The atomic view of the active site coupling termed channelling is a major | + | The atomic view of the active site coupling termed channelling is a major subject in molecular biology. We have determined two distinct crystal structures of the bacterial multienzyme complex that catalyzes the last three sequential reactions in the fatty acid beta-oxidation cycle. The alpha2beta2 heterotetrameric structure shows the uneven ring architecture, where all the catalytic centers of 2-enoyl-CoA hydratase (ECH), L-3-hydroxyacyl-CoA dehydrogenase (HACD) and 3-ketoacyl-CoA thiolase (KACT) face a large inner solvent region. The substrate, anchored through the 3'-phosphate ADP moiety, allows the fatty acid tail to pivot from the ECH to HACD active sites, and finally to the KACT active site. Coupling with striking domain rearrangements, the incorporation of the tail into the KACT cavity and the relocation of 3'-phosphate ADP bring the reactive C2-C3 bond to the correct position for cleavage. The alpha-helical linker specific for the multienzyme contributes to the pivoting center formation and the substrate transfer through its deformation. This channelling mechanism could be applied to other beta-oxidation multienzymes, as revealed from the homology model of the human mitochondrial trifunctional enzyme complex. |
==About this Structure== | ==About this Structure== | ||
| - | 1WDM is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Pseudomonas_fragi Pseudomonas fragi] with ZN, ACO and NAD as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Acetyl-CoA_C-acyltransferase Acetyl-CoA C-acyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.3.1.16 2.3.1.16] Full crystallographic information is available from [http:// | + | 1WDM is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Pseudomonas_fragi Pseudomonas fragi] with <scene name='pdbligand=ZN:'>ZN</scene>, <scene name='pdbligand=ACO:'>ACO</scene> and <scene name='pdbligand=NAD:'>NAD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Acetyl-CoA_C-acyltransferase Acetyl-CoA C-acyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.3.1.16 2.3.1.16] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1WDM OCA]. |
==Reference== | ==Reference== | ||
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[[Category: alpha2beta2 heterotetrameric complex]] | [[Category: alpha2beta2 heterotetrameric complex]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:43:07 2008'' |
Revision as of 13:43, 21 February 2008
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fatty acid beta-oxidation multienzyme complex from Pseudomonas fragi, form I (native3)
Overview
The atomic view of the active site coupling termed channelling is a major subject in molecular biology. We have determined two distinct crystal structures of the bacterial multienzyme complex that catalyzes the last three sequential reactions in the fatty acid beta-oxidation cycle. The alpha2beta2 heterotetrameric structure shows the uneven ring architecture, where all the catalytic centers of 2-enoyl-CoA hydratase (ECH), L-3-hydroxyacyl-CoA dehydrogenase (HACD) and 3-ketoacyl-CoA thiolase (KACT) face a large inner solvent region. The substrate, anchored through the 3'-phosphate ADP moiety, allows the fatty acid tail to pivot from the ECH to HACD active sites, and finally to the KACT active site. Coupling with striking domain rearrangements, the incorporation of the tail into the KACT cavity and the relocation of 3'-phosphate ADP bring the reactive C2-C3 bond to the correct position for cleavage. The alpha-helical linker specific for the multienzyme contributes to the pivoting center formation and the substrate transfer through its deformation. This channelling mechanism could be applied to other beta-oxidation multienzymes, as revealed from the homology model of the human mitochondrial trifunctional enzyme complex.
About this Structure
1WDM is a Protein complex structure of sequences from Pseudomonas fragi with , and as ligands. Active as Acetyl-CoA C-acyltransferase, with EC number 2.3.1.16 Full crystallographic information is available from OCA.
Reference
Structural basis for channelling mechanism of a fatty acid beta-oxidation multienzyme complex., Ishikawa M, Tsuchiya D, Oyama T, Tsunaka Y, Morikawa K, EMBO J. 2004 Jul 21;23(14):2745-54. Epub 2004 Jul 1. PMID:15229654
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