1u7h: Difference between revisions
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'''Structure and a Proposed Mechanism for Ornithine Cyclodeaminase from Pseudomonas putida''' | {{Structure | ||
|PDB= 1u7h |SIZE=350|CAPTION= <scene name='initialview01'>1u7h</scene>, resolution 1.80Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=NA:SODIUM+ION'>NA</scene>, <scene name='pdbligand=NAD:NICOTINAMIDE-ADENINE-DINUCLEOTIDE'>NAD</scene> and <scene name='pdbligand=MPD:(4S)-2-METHYL-2,4-PENTANEDIOL'>MPD</scene> | |||
|ACTIVITY= [http://en.wikipedia.org/wiki/Ornithine_cyclodeaminase Ornithine cyclodeaminase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.3.1.12 4.3.1.12] | |||
|GENE= Ornithine Cyclase (deaminating) ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=303 Pseudomonas putida]) | |||
}} | |||
'''Structure and a Proposed Mechanism for Ornithine Cyclodeaminase from Pseudomonas putida''' | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
1U7H is a [ | 1U7H is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_putida Pseudomonas putida]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1U7H OCA]. | ||
==Reference== | ==Reference== | ||
Ornithine cyclodeaminase: structure, mechanism of action, and implications for the mu-crystallin family., Goodman JL, Wang S, Alam S, Ruzicka FJ, Frey PA, Wedekind JE, Biochemistry. 2004 Nov 9;43(44):13883-91. PMID:[http:// | Ornithine cyclodeaminase: structure, mechanism of action, and implications for the mu-crystallin family., Goodman JL, Wang S, Alam S, Ruzicka FJ, Frey PA, Wedekind JE, Biochemistry. 2004 Nov 9;43(44):13883-91. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/15518536 15518536] | ||
[[Category: Ornithine cyclodeaminase]] | [[Category: Ornithine cyclodeaminase]] | ||
[[Category: Pseudomonas putida]] | [[Category: Pseudomonas putida]] | ||
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[[Category: rossmann fold]] | [[Category: rossmann fold]] | ||
''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 14:28:16 2008'' | ||
Revision as of 15:28, 20 March 2008
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| , resolution 1.80Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , and | ||||||
| Gene: | Ornithine Cyclase (deaminating) (Pseudomonas putida) | ||||||
| Activity: | Ornithine cyclodeaminase, with EC number 4.3.1.12 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Structure and a Proposed Mechanism for Ornithine Cyclodeaminase from Pseudomonas putida
OverviewOverview
Ornithine cyclodeaminase catalyzes the conversion of L-ornithine to L-proline by an NAD(+)-dependent hydride transfer reaction that culminates in ammonia elimination. Phylogenetic comparisons of amino acid sequences revealed that the enzyme belongs to the mu-crystallin protein family whose three-dimensional fold has not been reported. Here we describe the crystal structure of ornithine cyclodeaminase in complex with NADH, refined to 1.80 A resolution. The enzyme consists of a homodimeric fold whose subunits comprise two functional regions: (i) a novel substrate-binding domain whose antiparallel beta-strands form a 14-stranded barrel at the oligomeric interface and (ii) a canonical Rossmann fold that interacts with a single dinucleotide positioned for re hydride transfer. The adenosyl moiety of the cofactor resides in a solvent-exposed crevice on the protein surface and makes contact with a "domain-swapped"-like coil-helix module originating from the dyad-related molecule. Diffraction data were also collected to 1.60 A resolution on crystals grown in the presence of l-ornithine. The structure revealed that the substrate carboxyl group interacts with the side chains of Arg45, Lys69, and Arg112. In addition, the ammonia leaving group hydrogen bonds to the side chain of Asp228 and the site of hydride transfer is 3.8 A from C4 of the nicotinamide. The absence of an appropriately positioned water suggested that a previously proposed mechanism that calls for hydrolytic elimination of the imino intermediate must be reconsidered. A more parsimonious description of the chemical mechanism is proposed and discussed in relation to the structure and function of mu-crystallins.
About this StructureAbout this Structure
1U7H is a Single protein structure of sequence from Pseudomonas putida. Full crystallographic information is available from OCA.
ReferenceReference
Ornithine cyclodeaminase: structure, mechanism of action, and implications for the mu-crystallin family., Goodman JL, Wang S, Alam S, Ruzicka FJ, Frey PA, Wedekind JE, Biochemistry. 2004 Nov 9;43(44):13883-91. PMID:15518536
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