2c2s
From Proteopedia
Human Dihydrofolate Reductase Complexed With NADPH and 2,4-Diamino-5-(1-o-carboranylmethyl)-6-methylpyrimidine, A novel boron containing, nonclassical Antifolate
Structural highlights
Disease[DYR_HUMAN] Defects in DHFR are the cause of megaloblastic anemia due to dihydrofolate reductase deficiency (DHFRD) [MIM:613839]. DHFRD is an inborn error of metabolism, characterized by megaloblastic anemia and/or pancytopenia, severe cerebral folate deficiency, and cerebral tetrahydrobiopterin deficiency. Clinical features include variable neurologic symptoms, ranging from severe developmental delay and generalized seizures in infancy, to childhood absence epilepsy with learning difficulties, to lack of symptoms.[1] [2] Function[DYR_HUMAN] Key enzyme in folate metabolism. Contributes to the de novo mitochondrial thymidylate biosynthesis pathway. Catalyzes an essential reaction for de novo glycine and purine synthesis, and for DNA precursor synthesis. Binds its own mRNA and that of DHFRL1.[3] [4] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedTwo boron-containing, ortho-icosahedral carborane lipophilic antifolates were synthesized, and the crystal structures of their ternary complexes with human dihydrofolate reductase (DHFR) and dihydronicotinamide adenine dinucleotide phosphate were determined. The compounds were screened for activity against DHFR from six sources (human, rat liver, Pneumocystis carinii, Toxoplasma gondii, Mycobacterium avium, and Lactobacillus casei) and showed good to modest activity against these enzymes. The compounds were also tested for antibacterial activity against L. casei, M. tuberculosis H37Ra, and three M. avium strains and for cytotoxic activity against seven different human tumor cell lines. Antibacterial and cytotoxic activity was modest, with one sample, the closo-carborane 4, showing about 10-fold greater activity. The less toxic nido-carborane 2 was also tested as a candidate for boron neutron capture therapy, but showed poor tumor retention and low selectivity ratios for boron distribution in tumor tissue versus normal tissue. Novel boron-containing, nonclassical antifolates: synthesis and preliminary biological and structural evaluation.,Reynolds RC, Campbell SR, Fairchild RG, Kisliuk RL, Micca PL, Queener SF, Riordan JM, Sedwick WD, Waud WR, Leung AK, Dixon RW, Suling WJ, Borhani DW J Med Chem. 2007 Jul 12;50(14):3283-9. Epub 2007 Jun 15. PMID:17569517[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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