2gci
From Proteopedia
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| - | [[Image:2gci.gif|left|200px]] | + | [[Image:2gci.gif|left|200px]] |
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| - | '''The 1,1-proton transfer reaction mechanism by alpha-methylacyl-CoA racemase is catalyzed by an asparte/histidine pair and involves a smooth, methionine-rich surface for binding the fatty acyl moiety''' | + | {{Structure |
| + | |PDB= 2gci |SIZE=350|CAPTION= <scene name='initialview01'>2gci</scene>, resolution 1.60Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=MRR:(R)-2-METHYLMYRISTOYL-COENZYME+A'>MRR</scene> and <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Alpha-methylacyl-CoA_racemase Alpha-methylacyl-CoA racemase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.1.99.4 5.1.99.4] | ||
| + | |GENE= CAB09301 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1773 Mycobacterium tuberculosis]) | ||
| + | }} | ||
| + | |||
| + | '''The 1,1-proton transfer reaction mechanism by alpha-methylacyl-CoA racemase is catalyzed by an asparte/histidine pair and involves a smooth, methionine-rich surface for binding the fatty acyl moiety''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 2GCI is a [ | + | 2GCI is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Mycobacterium_tuberculosis Mycobacterium tuberculosis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2GCI OCA]. |
==Reference== | ==Reference== | ||
| - | The catalysis of the 1,1-proton transfer by alpha-methyl-acyl-CoA racemase is coupled to a movement of the fatty acyl moiety over a hydrophobic, methionine-rich surface., Bhaumik P, Schmitz W, Hassinen A, Hiltunen JK, Conzelmann E, Wierenga RK, J Mol Biol. 2007 Apr 6;367(4):1145-61. Epub 2007 Jan 27. PMID:[http:// | + | The catalysis of the 1,1-proton transfer by alpha-methyl-acyl-CoA racemase is coupled to a movement of the fatty acyl moiety over a hydrophobic, methionine-rich surface., Bhaumik P, Schmitz W, Hassinen A, Hiltunen JK, Conzelmann E, Wierenga RK, J Mol Biol. 2007 Apr 6;367(4):1145-61. Epub 2007 Jan 27. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17320106 17320106] |
[[Category: Alpha-methylacyl-CoA racemase]] | [[Category: Alpha-methylacyl-CoA racemase]] | ||
[[Category: Mycobacterium tuberculosis]] | [[Category: Mycobacterium tuberculosis]] | ||
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[[Category: alpha-methylacyl-coa racemase]] | [[Category: alpha-methylacyl-coa racemase]] | ||
[[Category: coa transferase]] | [[Category: coa transferase]] | ||
| - | [[Category: coenzyme | + | [[Category: coenzyme some]] |
[[Category: proton transfer]] | [[Category: proton transfer]] | ||
[[Category: racemase]] | [[Category: racemase]] | ||
| - | ''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 17:03:04 2008'' |
Revision as of 15:03, 20 March 2008
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| , resolution 1.60Å | |||||||
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| Ligands: | and | ||||||
| Gene: | CAB09301 (Mycobacterium tuberculosis) | ||||||
| Activity: | Alpha-methylacyl-CoA racemase, with EC number 5.1.99.4 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
The 1,1-proton transfer reaction mechanism by alpha-methylacyl-CoA racemase is catalyzed by an asparte/histidine pair and involves a smooth, methionine-rich surface for binding the fatty acyl moiety
Overview
Alpha-methylacyl-CoA racemases are essential enzymes for branched-chain fatty acid metabolism. Their reaction mechanism and the structural basis of their wide substrate specificity are poorly understood. High-resolution crystal structures of Mycobacterium tuberculosis alpha-methylacyl-CoA racemase (MCR) complexed with substrate molecules show the active site geometry required for catalysis of the interconversion of (2S) and (2R)-methylacyl-CoA. The thioester oxygen atom and the 2-methyl group are in a cis-conformation with respect to each other. The thioester oxygen atom fits into an oxyanion hole and the 2-methyl group points into a hydrophobic pocket. The active site geometry agrees with a 1,1-proton transfer mechanism in which the acid/base-pair residues are His126 and Asp156. The structures of the complexes indicate that the acyl chains of the S-substrate and the R-substrate bind in an S-pocket and an R-pocket, respectively. A unique feature of MCR is a large number of methionine residues in the acyl binding region, located between the S-pocket and the R-pocket. It appears that the (S) to (R) interconversion of the 2-methylacyl chiral center is coupled to a movement of the acyl group over this hydrophobic, methionine-rich surface, when moving from its S-pocket to its R-pocket, whereas the 2-methyl moiety and the CoA group remain fixed in their respective pockets.
About this Structure
2GCI is a Single protein structure of sequence from Mycobacterium tuberculosis. Full crystallographic information is available from OCA.
Reference
The catalysis of the 1,1-proton transfer by alpha-methyl-acyl-CoA racemase is coupled to a movement of the fatty acyl moiety over a hydrophobic, methionine-rich surface., Bhaumik P, Schmitz W, Hassinen A, Hiltunen JK, Conzelmann E, Wierenga RK, J Mol Biol. 2007 Apr 6;367(4):1145-61. Epub 2007 Jan 27. PMID:17320106
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