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| </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1b3o ConSurf]. | | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1b3o ConSurf]. |
| <div style="clear:both"></div> | | <div style="clear:both"></div> |
| <div style="background-color:#fffaf0;">
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| == Publication Abstract from PubMed ==
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| Inosine monophosphate dehydrogenase (IMPDH) controls a key metabolic step in the regulation of cell growth and differentiation. This step is the NAD-dependent oxidation of inosine 5' monophosphate (IMP) to xanthosine 5' monophosphate, the rate-limiting step in the synthesis of the guanine nucleotides. Two isoforms of IMPDH have been identified, one of which (type II) is significantly up- regulated in neoplastic and differentiating cells. As such, it has been identified as a major target in antitumor and immunosuppressive drug design. We present here the 2.9-A structure of a ternary complex of the human type II isoform of IMPDH. The complex contains the substrate analogue 6-chloropurine riboside 5'-monophosphate (6-Cl-IMP) and the NAD analogue selenazole-4-carboxamide adenine dinucleotide, the selenium derivative of the active metabolite of the antitumor drug tiazofurin. The enzyme forms a homotetramer, with the dinucleotide binding at the monomer-monomer interface. The 6 chloro-substituted purine base is dehalogenated, forming a covalent adduct at C6 with Cys-331. The dinucleotide selenazole base is stacked against the 6-Cl-IMP purine ring in an orientation consistent with the B-side stereochemistry of hydride transfer seen with NAD. The adenosine end of the ligand interacts with residues not conserved between the type I and type II isoforms, suggesting strategies for the design of isoform-specific agents.
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| Crystal structure of human type II inosine monophosphate dehydrogenase: implications for ligand binding and drug design.,Colby TD, Vanderveen K, Strickler MD, Markham GD, Goldstein BM Proc Natl Acad Sci U S A. 1999 Mar 30;96(7):3531-6. PMID:10097070<ref>PMID:10097070</ref>
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| From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
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| </div>
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| <div class="pdbe-citations 1b3o" style="background-color:#fffaf0;"></div>
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| ==See Also== | | ==See Also== |
| *[[Inosine monophosphate dehydrogenase|Inosine monophosphate dehydrogenase]] | | *[[Inosine monophosphate dehydrogenase|Inosine monophosphate dehydrogenase]] |
| *[[Inosine monophosphate dehydrogenase 3D structures|Inosine monophosphate dehydrogenase 3D structures]] | | *[[Inosine monophosphate dehydrogenase 3D structures|Inosine monophosphate dehydrogenase 3D structures]] |
| == References ==
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| <references/>
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| __TOC__ | | __TOC__ |
| </StructureSection> | | </StructureSection> |