1jhq
From Proteopedia
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|PDB= 1jhq |SIZE=350|CAPTION= <scene name='initialview01'>1jhq</scene>, resolution 2.0Å | |PDB= 1jhq |SIZE=350|CAPTION= <scene name='initialview01'>1jhq</scene>, resolution 2.0Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=PMO:N1-(5'-PHOSPHO-ALPHA-RIBOSYL)-5-METHOXYBENZIMIDAZOLE'>PMO</scene> | + | |LIGAND= <scene name='pdbligand=NIO:NICOTINIC+ACID'>NIO</scene>, <scene name='pdbligand=PMO:N1-(5'-PHOSPHO-ALPHA-RIBOSYL)-5-METHOXYBENZIMIDAZOLE'>PMO</scene> |
| - | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Nicotinate-nucleotide--dimethylbenzimidazole_phosphoribosyltransferase Nicotinate-nucleotide--dimethylbenzimidazole phosphoribosyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.2.21 2.4.2.21] </span> | |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1d0s|1D0S]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1jhq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jhq OCA], [http://www.ebi.ac.uk/pdbsum/1jhq PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1jhq RCSB]</span> | ||
}} | }} | ||
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[[Category: Escalante-Semerena, J.]] | [[Category: Escalante-Semerena, J.]] | ||
[[Category: Rayment, I.]] | [[Category: Rayment, I.]] | ||
| - | [[Category: NIO]] | ||
| - | [[Category: PMO]] | ||
[[Category: cobalamin biosynthesis]] | [[Category: cobalamin biosynthesis]] | ||
[[Category: cobamide]] | [[Category: cobamide]] | ||
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[[Category: nn:dbi prt]] | [[Category: nn:dbi prt]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:33:54 2008'' |
Revision as of 18:33, 30 March 2008
| |||||||
| , resolution 2.0Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Activity: | Nicotinate-nucleotide--dimethylbenzimidazole phosphoribosyltransferase, with EC number 2.4.2.21 | ||||||
| Related: | 1D0S
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Three-dimensional Structure of CobT in Complex with Reaction Products of 5-methoxybenzimidazole and NaMN
Overview
Nicotinate mononucleotide (NaMN):5,6-dimethylbenzimidazole phosphoribosyltransferase (CobT) from Salmonella enterica plays a central role in the synthesis of alpha-ribazole, a key component of the lower ligand of cobalamin. Surprisingly, CobT can phosphoribosylate a wide range of aromatic substrates, giving rise to a wide variety of lower ligands in cobamides. To understand the molecular basis for this lack of substrate specificity, the x-ray structures of CobT complexed with adenine, 5-methylbenzimidazole, 5-methoxybenzimidazole, p-cresol, and phenol were determined. Furthermore, adenine, 5-methylbenzimidazole, 5-methoxybenzimidazole, and 2-hydroxypurine were observed to react with NaMN within the crystal lattice and undergo the phosphoribosyl transfer reaction to form product. Significantly, the stereochemistries of all products are identical to those found in vivo. Interestingly, p-cresol and phenol, which are the lower ligand in Sporomusa ovata, bound to CobT but did not react with NaMN. This study provides a structural explanation for how CobT can phosphoribosylate most of the commonly observed lower ligands found in cobamides with the exception of the phenolic lower ligands observed in S. ovata. This is accomplished with minor conformational changes in the side chains that constitute the 5,6-dimethylbenzimidazole binding site. These investigations are consistent with the implication that the nature of the lower ligand is controlled by metabolic factors rather by the specificity of the phosphoribosyltransferase.
About this Structure
1JHQ is a Single protein structure of sequence from Salmonella enterica. Full crystallographic information is available from OCA.
Reference
Structural investigation of the biosynthesis of alternative lower ligands for cobamides by nicotinate mononucleotide: 5,6-dimethylbenzimidazole phosphoribosyltransferase from Salmonella enterica., Cheong CG, Escalante-Semerena JC, Rayment I, J Biol Chem. 2001 Oct 5;276(40):37612-20. Epub 2001 Jul 5. PMID:11441022
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