1z7e
From Proteopedia
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|PDB= 1z7e |SIZE=350|CAPTION= <scene name='initialview01'>1z7e</scene>, resolution 3.00Å | |PDB= 1z7e |SIZE=350|CAPTION= <scene name='initialview01'>1z7e</scene>, resolution 3.00Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=ATP:ADENOSINE-5 | + | |LIGAND= <scene name='pdbligand=ATP:ADENOSINE-5'-TRIPHOSPHATE'>ATP</scene> and <scene name='pdbligand=UGA:URIDINE-5'-DIPHOSPHATE-GLUCURONIC ACID'>UGA</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= PMRI, YFBG ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | |GENE= PMRI, YFBG ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | ||
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[[Category: rossmann fold; ob-like fold]] | [[Category: rossmann fold; ob-like fold]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 23 14:26:48 2008'' |
Revision as of 12:26, 23 March 2008
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| , resolution 3.00Å | |||||||
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| Ligands: | and | ||||||
| Gene: | PMRI, YFBG (Escherichia coli) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of full length ArnA
Overview
The modification of lipid A with 4-amino-4-deoxy-L-arabinose (Ara4N) allows gram-negative bacteria to resist the antimicrobial activity of cationic antimicrobial peptides and antibiotics such as polymyxin. ArnA is the first enzyme specific to the lipid A-Ara4N pathway. It contains two functionally and physically separable domains: a dehydrogenase domain (ArnA_DH) catalyzing the NAD+-dependent oxidative decarboxylation of UDP-Glucuronic acid (UDP-GlcA), and a transformylase domain that formylates UDP-Ara4N. Here, we describe the crystal structure of the full-length bifunctional ArnA with UDP-GlcA and ATP bound to the dehydrogenase domain. Binding of UDP-GlcA triggers a 17 A conformational change in ArnA_DH that opens the NAD+ binding site while trapping UDP-GlcA. We propose an ordered mechanism of substrate binding and product release. Mutation of residues R619 and S433 demonstrates their importance in catalysis and suggests that R619 functions as a general acid in catalysis. The proposed mechanism for ArnA_DH has important implications for the design of selective inhibitors.
About this Structure
1Z7E is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Structure and mechanism of ArnA: conformational change implies ordered dehydrogenase mechanism in key enzyme for polymyxin resistance., Gatzeva-Topalova PZ, May AP, Sousa MC, Structure. 2005 Jun;13(6):929-42. PMID:15939024
Page seeded by OCA on Sun Mar 23 14:26:48 2008
