2a81
From Proteopedia
| Line 4: | Line 4: | ||
|PDB= 2a81 |SIZE=350|CAPTION= <scene name='initialview01'>2a81</scene>, resolution 3.150Å | |PDB= 2a81 |SIZE=350|CAPTION= <scene name='initialview01'>2a81</scene>, resolution 3.150Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=ACO:ACETYL+COENZYME+*A'>ACO</scene> | + | |LIGAND= <scene name='pdbligand=ACO:ACETYL+COENZYME+*A'>ACO</scene>, <scene name='pdbligand=BCN:BICINE'>BCN</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= CarB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=554 Pectobacterium carotovorum]) | |GENE= CarB ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=554 Pectobacterium carotovorum]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[2a7k|2A7K]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2a81 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2a81 OCA], [http://www.ebi.ac.uk/pdbsum/2a81 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=2a81 RCSB]</span> | ||
}} | }} | ||
| Line 27: | Line 30: | ||
[[Category: Sleeman, M C.]] | [[Category: Sleeman, M C.]] | ||
[[Category: Sorensen, J L.]] | [[Category: Sorensen, J L.]] | ||
| - | [[Category: ACO]] | ||
| - | [[Category: BCN]] | ||
[[Category: acetyl coenzyme some]] | [[Category: acetyl coenzyme some]] | ||
[[Category: antibiotic]] | [[Category: antibiotic]] | ||
| Line 37: | Line 38: | ||
[[Category: crotonase]] | [[Category: crotonase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 01:49:04 2008'' |
Revision as of 22:49, 30 March 2008
| |||||||
| , resolution 3.150Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Gene: | CarB (Pectobacterium carotovorum) | ||||||
| Related: | 2A7K
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
carboxymethylproline synthase (CarB) from pectobacterium carotovora, complexed with acetyl CoA and bicine
Overview
The first step in the biosynthesis of the medicinally important carbapenem family of beta-lactam antibiotics is catalyzed by carboxymethylproline synthase (CarB), a unique member of the crotonase superfamily. CarB catalyzes formation of (2S,5S)-carboxymethylproline [(2S,5S)-t-CMP] from malonyl-CoA and l-glutamate semialdehyde. In addition to using a cosubstrate, CarB catalyzes C-C and C-N bond formation processes as well as an acyl-coenzyme A hydrolysis reaction. We describe the crystal structure of CarB in the presence and absence of acetyl-CoA at 2.24 A and 3.15 A resolution, respectively. The structures reveal that CarB contains a conserved oxy-anion hole probably required for decarboxylation of malonyl-CoA and stabilization of the resultant enolate. Comparison of the structures reveals that conformational changes (involving His(229)) in the cavity predicted to bind l-glutamate semialdehyde occur on (co)substrate binding. Mechanisms for the formation of the carboxymethylproline ring are discussed in the light of the structures and the accompanying studies using isotopically labeled substrates; cyclization via 1,4-addition is consistent with the observed labeling results (providing that hydrogen exchange at the C-6 position of carboxymethylproline does not occur). The side chain of Glu(131) appears to be positioned to be involved in hydrolysis of the carboxymethylproline-CoA ester intermediate. Labeling experiments ruled out the possibility that hydrolysis proceeds via an anhydride in which water attacks a carbonyl derived from Glu(131), as proposed for 3-hydroxyisobutyryl-CoA hydrolase. The structural work will aid in mutagenesis studies directed at altering the selectivity of CarB to provide intermediates for the production of clinically useful carbapenems.
About this Structure
2A81 is a Single protein structure of sequence from Pectobacterium carotovorum. Full crystallographic information is available from OCA.
Reference
Structural and mechanistic studies on carboxymethylproline synthase (CarB), a unique member of the crotonase superfamily catalyzing the first step in carbapenem biosynthesis., Sleeman MC, Sorensen JL, Batchelar ET, McDonough MA, Schofield CJ, J Biol Chem. 2005 Oct 14;280(41):34956-65. Epub 2005 Aug 11. PMID:16096274
Page seeded by OCA on Mon Mar 31 01:49:04 2008
