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1kms
From Proteopedia
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HUMAN DIHYDROFOLATE REDUCTASE COMPLEXED WITH NADPH AND 6-([5-QUINOLYLAMINO]METHYL)-2,4-DIAMINO-5-METHYLPYRIDO[2,3-D]PYRIMIDINE (SRI-9439), A LIPOPHILIC ANTIFOLATE
Contents |
Overview
The crystal structures of two human dihydrofolate reductase (hDHFR) ternary complexes, each with bound NADPH cofactor and a lipophilic antifolate inhibitor, have been determined at atomic resolution. The potent inhibitors 6-([5-quinolylamino]methyl)-2,4-diamino-5-methylpyrido[2,3-d]pyrimidine (SRI-9439) and (Z)-6-(2-[2,5-dimethoxyphenyl]ethen-1-yl)-2,4-diamino-5-methylpyrido[2,3-d ]pyrimidine (SRI-9662) were developed at Southern Research Institute against Toxoplasma gondii DHFR-thymidylate synthase. The 5-deazapteridine ring of each inhibitor adopts an unusual puckered conformation that enables the formation of identical contacts in the active site. Conversely, the quinoline and dimethoxybenzene moieties exhibit distinct binding characteristics that account for the differences in inhibitory activity. In both structures, a salt-bridge is formed between Arg70 in the active site and Glu44 from a symmetry-related molecule in the crystal lattice that mimics the binding of methotrexate to DHFR.
Disease
Known disease associated with this structure: Anemia, megaloblastic, due to DHFR deficiency (1) OMIM:[126060]
About this Structure
1KMS is a Single protein structure of sequence from Homo sapiens with , and as ligands. Active as Dihydrofolate reductase, with EC number 1.5.1.3 Full crystallographic information is available from OCA.
Reference
Atomic structures of human dihydrofolate reductase complexed with NADPH and two lipophilic antifolates at 1.09 a and 1.05 a resolution., Klon AE, Heroux A, Ross LJ, Pathak V, Johnson CA, Piper JR, Borhani DW, J Mol Biol. 2002 Jul 12;320(3):677-93. PMID:12096917
Page seeded by OCA on Thu Feb 21 13:35:50 2008
