Zobrazeno 1 - 10
of 126
pro vyhledávání: '"James H. Freisheim"'
Publikováno v:
Photochemistry and Photobiology. 62:71-81
— Photosensitized L-biopterin induces the transfer of a hydrogen atom from the dihydronico-tinamide moiety of NADPH to the biopterin ring. Sensitization occurs through the triplet state of both the lactim and lactam tautomers of L-biopterin. Quench
Publikováno v:
Journal of Molecular Biology. 247:309-325
Previous NMR studies on the ternary complex of human dihydrofolate reductase (hDHFR) with methotrexate (MTX) and NADPH detected six long-lived bound water molecules. Two of the water molecules, WatA and WatB, stabilize the structure of the protein wh
Publikováno v:
Archives of Biochemistry and Biophysics. 306:501-509
Nuclear magnetic resonance (NMR) spectra for [2-amino,3-15N2]folate and [2-13C]folate complexed with human dihydrofolate reductase, and for complexes of similarly labeled dihydrofolate, show that the N-3 proton of bound folate or dihydrofolate exchan
Autor:
Zenia Nimec, Brigid M. O'Connor, Robert F. Rotundo, James A. Dias, John Galivan, James H. Freisheim, Ying Wang
Publikováno v:
Advances in Enzyme Regulation. 33:207-218
gamma-Glutamyl hydrolase is a ubiquitous enzyme that has the capacity to cleave gamma-glutamyl bonds of cellular folyl- and antifolylpoly-gamma-glutamates. This study has revealed that the enzyme is secreted by primary cultures of rat hepatocytes and
Publikováno v:
ChemInform. 22
The new folate antagonist, 5-fluoro-5,8-dideazaisoaminopterin was synthesized in four steps beginning with 2,4-diamino-5-fluoroquinazoline. It was found to be a potent inhibitor of human dihydrofolate reductase. Against L1210 leukemia in mice, 5-fluo
Publikováno v:
ChemInform. 23
A series of thirty eight 2,4-diaminoquinazolines having diverse substitution patterns on the aromatic ring was evaluated for inhibitory activity against dihydrofolate reductase (DHFR) obtained from a human lymphoblast cell line. Many of these compoun
Publikováno v:
Journal of Medicinal Chemistry. 35:1578-1588
5-Deazafolate and 6-deazatetrahydrofolate (DATHF) analogues with the glutamic acid side chain replaced by homocysteic aicd (HCysA), 2-amino-4-phosphonobutanoic acid (APBA), and ornithine (Om) were synthesized as part of a larger program directed towa
Publikováno v:
Journal of Biological Chemistry. 267:864-870
Substrate and inhibitor binding to dihydrofolate reductase (DHFR) primarily involves residues in the amino-terminal half of the enzyme; however, antibody binding studies performed in this laboratory suggested that the loop region located in the carbo
Autor:
N. R. Nirmala, James H. Freisheim, Tavner J. Delcamp, Gerhard Wagner, Brian J. Stockman, Michael T. DeYarman
Publikováno v:
Biochemistry. 31:218-229
Dihydrofolate reductase is an intracellular target enzyme for folate antagonists, including the anticancer drug methotrexate. In order to design novel drugs with altered binding properties, a detailed description of protein-drug interactions in solut
Publikováno v:
Journal of Heterocyclic Chemistry. 28:1981-1986
A series of thirty eight 2,4-diaminoquinazolines having diverse substitution patterns on the aromatic ring was evaluated for inhibitory activity against dihydrofolate reductase (DHFR) obtained from a human lymphoblast cell line. Many of these compoun