1u9j
From Proteopedia
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| - | [[Image:1u9j.gif|left|200px]] | + | [[Image:1u9j.gif|left|200px]] |
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| - | '''Crystal Structure of E. coli ArnA (PmrI) Decarboxylase Domain''' | + | {{Structure |
| + | |PDB= 1u9j |SIZE=350|CAPTION= <scene name='initialview01'>1u9j</scene>, resolution 2.40Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=SO4:SULFATE ION'>SO4</scene> | ||
| + | |ACTIVITY= | ||
| + | |GENE= PmrI, yfbG ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli]) | ||
| + | }} | ||
| + | |||
| + | '''Crystal Structure of E. coli ArnA (PmrI) Decarboxylase Domain''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1U9J is a [ | + | 1U9J is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1U9J OCA]. |
==Reference== | ==Reference== | ||
| - | Crystal structure of Escherichia coli ArnA (PmrI) decarboxylase domain. A key enzyme for lipid A modification with 4-amino-4-deoxy-L-arabinose and polymyxin resistance., Gatzeva-Topalova PZ, May AP, Sousa MC, Biochemistry. 2004 Oct 26;43(42):13370-9. PMID:[http:// | + | Crystal structure of Escherichia coli ArnA (PmrI) decarboxylase domain. A key enzyme for lipid A modification with 4-amino-4-deoxy-L-arabinose and polymyxin resistance., Gatzeva-Topalova PZ, May AP, Sousa MC, Biochemistry. 2004 Oct 26;43(42):13370-9. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/15491143 15491143] |
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: decarboxylase; x-ray structure; e coli proteome]] | [[Category: decarboxylase; x-ray structure; e coli proteome]] | ||
| - | ''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 14:29:02 2008'' |
Revision as of 12:29, 20 March 2008
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| , resolution 2.40Å | |||||||
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| Ligands: | |||||||
| Gene: | PmrI, yfbG (Escherichia coli) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal Structure of E. coli ArnA (PmrI) Decarboxylase Domain
Overview
Gram-negative bacteria including Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa can modify the structure of lipid A in their outer membrane with 4-amino-4-deoxy-l-arabinose (Ara4N). Such modification results in resistance to cationic antimicrobial peptides of the innate immune system and antibiotics such as polymyxin. ArnA is a key enzyme in the lipid A modification pathway, and its deletion abolishes both the Ara4N-lipid A modification and polymyxin resistance. ArnA is a bifunctional enzyme. It can catalyze (i) the NAD(+)-dependent decarboxylation of UDP-glucuronic acid to UDP-4-keto-arabinose and (ii) the N-10-formyltetrahydrofolate-dependent formylation of UDP-4-amino-4-deoxy-l-arabinose. We show that the NAD(+)-dependent decarboxylating activity is contained in the 360 amino acid C-terminal domain of ArnA. This domain is separable from the N-terminal fragment, and its activity is identical to that of the full-length enzyme. The crystal structure of the ArnA decarboxylase domain from E. coli is presented here. The structure confirms that the enzyme belongs to the short-chain dehydrogenase/reductase (SDR) family. On the basis of sequence and structure comparisons of the ArnA decarboxylase domain with other members of the short-chain dehydrogenase/reductase (SDR) family, we propose a binding model for NAD(+) and UDP-glucuronic acid and the involvement of residues T(432), Y(463), K(467), R(619), and S(433) in the mechanism of NAD(+)-dependent oxidation of the 4-OH of the UDP-glucuronic acid and decarboxylation of the UDP-4-keto-glucuronic acid intermediate.
About this Structure
1U9J is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of Escherichia coli ArnA (PmrI) decarboxylase domain. A key enzyme for lipid A modification with 4-amino-4-deoxy-L-arabinose and polymyxin resistance., Gatzeva-Topalova PZ, May AP, Sousa MC, Biochemistry. 2004 Oct 26;43(42):13370-9. PMID:15491143
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