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Kuramochi K, Miyano Y, Enomoto Y, Takeuchi R, Ishi K, Takakusagi Y, Saitoh T, Fukudome K, Manita D, Takeda Y, Kobayashi S, Sakaguchi K, Sugawara F. Identification of small molecule binding molecules by affinity purification using a specific ligand immobilized on PEGA resin. Bioconjug Chem 2009; 19:2417-26. [PMID: 19035789 DOI: 10.1021/bc8002716] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We investigated the application of resins used in solid-phase synthesis for affinity purification. A synthetic ligand for FK506-binding protein 12 (SLF) was immobilized on various resins, and the binding assays between the SLF-immobilized resins and FK506-binding protein 12 (FKBP12) were performed. Of the resins tested in this study, PEGA resin was the most effective for isolating FKBP12. This matrix enabled the isolation of FKBP12 from a cell lysate, and the identification of SLF-binding peptides from a phage cDNA library. We confirmed the interaction between SLF and these peptides using a cuvette type quartz crystal microbalance (QCM) apparatus. Our study suggests that PEGA resin has great potential as a tool not only for the purification and identification of small-molecule binding proteins but also for the selection of peptides that recognize target molecules.
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Affiliation(s)
- Kouji Kuramochi
- Department of Applied Biological Science, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
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Roberts GC. Origins of specificity in the binding of small molecules to dihydrofolate reductase. CIBA FOUNDATION SYMPOSIUM 2008:89-104. [PMID: 32020 DOI: 10.1002/9780470720424.ch7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Dihydrofolate reductase is the target for the therapeutically important 'anti-folate' drugs such as methotrexate and trimethoprim. Methotrexate is a powerful inhibitor of the enzyme, binding up to 10,000 times more tightly than the structurally similar substrate, folate. Two contributions to this striking difference in affinity have been identified: the two ligands bind in different charge states, and there are conformational differences between the two complexes. The origins of the tight binding of methotrexate have been explored further by studying the binding of 2,4-diaminopyrimidine and p-aminobenzoyl-L-glutamate, which may be considered as 'fragments' of methotrexate. These two compounds bind simultaneously but also cooperatively, the binding of one 'fragment' leading to a 50-fold increase in the affinity for the other. Studies of structural analogues of these fragments show that the specificity as well as the strength of binding can be altered by the presence of the other 'fragment'; both positive and negative cooperativity are observed. The relation of these observations to methotrexate binding, and the notion of intramolecular cooperativity in ligand binding are discussed.
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MESH Headings
- Chromatography, Affinity/methods
- Chromatography, Gel/methods
- Cloning, Molecular
- Crystallization
- Dimerization
- Enzyme Stability
- Escherichia coli
- Gram-Negative Anaerobic Straight, Curved, and Helical Rods/enzymology
- Gram-Negative Anaerobic Straight, Curved, and Helical Rods/genetics
- Gram-Negative Anaerobic Straight, Curved, and Helical Rods/growth & development
- Guanidine
- Methotrexate/metabolism
- Molecular Weight
- Recombinant Proteins/chemistry
- Recombinant Proteins/isolation & purification
- Recombinant Proteins/metabolism
- Spectrophotometry, Ultraviolet
- Tetrahydrofolate Dehydrogenase/chemistry
- Tetrahydrofolate Dehydrogenase/genetics
- Tetrahydrofolate Dehydrogenase/isolation & purification
- Tetrahydrofolate Dehydrogenase/metabolism
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Affiliation(s)
- T Dams
- Abteilung Strukturforschung, Max Planck Institut für Biochemie, Martinsried D-82151, Germany
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Chen YQ, Gulotta M, Cheung HTA, Callender R. Light Activates Reduction of Methotrexate by NADPH in the Ternary Complex with Escherichia coli Dihydrofolate Reductase. Photochem Photobiol 1999. [DOI: 10.1111/j.1751-1097.1999.tb05309.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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5
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Guéra A, America T, van Waas M, Weisbeek PJ. A strong protein unfolding activity is associated with the binding of precursor chloroplast proteins to chloroplast envelopes. PLANT MOLECULAR BIOLOGY 1993; 23:309-324. [PMID: 8219067 DOI: 10.1007/bf00029007] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Protein conformational changes related to transport into chloroplasts have been studied. Two chimaeric proteins carrying the transit peptide of either ferredoxin or plastocyanin linked to the mouse cytosolic enzyme dihydrofolate reductase (EC 1.5.1.3.) were employed. In contrast to observations in mitochondria, we found in chloroplasts that transport of a purified ferredoxin-dihydrofolate reductase fusion protein is not blocked by the presence of methotrexate, a folate analogue that stabilizes the structural conformation of dihydrofolate reductase. It is shown that transport competence of this protein in the presence of methotrexate is not a consequence of alteration of the folding characteristics or methotrexate binding properties of dihydrofolate reductase by fusion to the ferredoxin transit peptide. Binding of dihydrofolate reductase fusion proteins to chloroplast envelopes is not inhibited by low temperature and it is only partially diminished by methotrexate. It is demonstrated that the dihydrofolate reductase fusion proteins unfold, despite the presence of methotrexate, on binding to the chloroplast envelopes. We propose the existence of a strong protein unfolding activity associated to the chloroplast envelopes.
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Affiliation(s)
- A Guéra
- Institut de Biologie Moleculaire des Plantes du CNRS, Strasbourg, France
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6
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Pryer NK, Salama NR, Schekman R, Kaiser CA. Cytosolic Sec13p complex is required for vesicle formation from the endoplasmic reticulum in vitro. J Cell Biol 1993; 120:865-75. [PMID: 8432727 PMCID: PMC2200066 DOI: 10.1083/jcb.120.4.865] [Citation(s) in RCA: 117] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The SEC13 gene of Saccharomyces cerevisiae is required in vesicle biogenesis at a step before or concurrent with the release of transport vesicles from the ER membrane. SEC13 encodes a 33-kD protein with sequence homology to a series of conserved internal repeat motifs found in beta subunits of heterotrimeric G proteins. The product of this gene, Sec13p, is a cytosolic protein peripherally associated with membranes. We developed a cell-free Sec13p-dependent vesicle formation reaction. Sec13p-depleted membranes and cytosol fractions were generated by urea treatment of membranes and affinity depletion of a Sec13p-dihydrofolate reductase fusion protein, respectively. These fractions were unable to support vesicle formation from the ER unless cytosol containing Sec13p was added. Cytosolic Sec13p fractionated by gel filtration as a large complex of about 700 kD. Fractions containing the Sec13p complex restored activity to the Sec13p- dependent vesicle formation reaction. Expression of SEC13 on a multicopy plasmid resulted in overproduction of a monomeric form of Sec13p, suggesting that another member of the complex becomes limiting when Sec13p is overproduced. Overproduced, monomeric Sec13p was inactive in the Sec13p-dependent vesicle formation assay.
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Affiliation(s)
- N K Pryer
- Department of Molecular and Cell Biology, University of California, Berkeley 94720
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7
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Buchwalder A, Szadkowski H, Kirschner K. A fully active variant of dihydrofolate reductase with a circularly permuted sequence. Biochemistry 1992; 31:1621-30. [PMID: 1737018 DOI: 10.1021/bi00121a006] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The amino acid sequence of mouse dihydrofolate reductase was permuted circularly at the level of the gene. By transposing the 3'-terminal half of the coding sequence to its 5' terminus, the naturally adjacent amino and carboxyl termini of the native protein were fused, and one of the flexible peptide loops at the protein surface was cleaved. The steady-state kinetic constants, the dissociation constants of folate analogues, and the degree of activation by both mercurials and salt as well as the resistance toward digestion by trypsin were almost indistinguishable from those of a recombinant wild-type protein. Judged by these criteria, the circularly permuted variant has the same active site and overall structure as the wild-type enzyme. The only significant difference was the lower stability toward guanidinium chloride and the lower solubility of the circularly permuted variant. This behavior may be due to moving a mononucleotide binding fold from the interior of the sequence to the carboxyl terminus. Thus, dihydrofolate reductase requires neither the natural termini nor the cleaved loop for stability, for the conformational changes that accompany catalysis as well as the binding of inhibitors, and for the folding process.
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Affiliation(s)
- A Buchwalder
- Abteilung Biophysikalische Chemie, Biozentrum der Universität, Basel, Switzerland
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8
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Loetscher P, Pratt G, Rechsteiner M. The C terminus of mouse ornithine decarboxylase confers rapid degradation on dihydrofolate reductase. Support for the pest hypothesis. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)99150-7] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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9
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Probing the role of two hydrophobic active site residues in the human dihydrofolate reductase by site-directed mutagenesis. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(19)47131-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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10
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Kinetics of the formation and isomerization of methotrexate complexes of recombinant human dihydrofolate reductase. J Biol Chem 1988. [DOI: 10.1016/s0021-9258(19)81516-8] [Citation(s) in RCA: 94] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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11
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Eilers M, Schatz G. Binding of a specific ligand inhibits import of a purified precursor protein into mitochondria. Nature 1986; 322:228-32. [PMID: 3016548 DOI: 10.1038/322228a0] [Citation(s) in RCA: 515] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Methotrexate, a folate antagonist, blocks import into mitochondria of mouse dihydrofolate reductase fused to a mitochondrial presequence. Methotrexate does not mask the presequence, but stabilizes the dihydrofolate reductase moiety. It does not inhibit import of the authentic precursor from which the presequence is derived. This suggests that dihydrofolate reductase must at least partly unfold in order to be transported across mitochondrial membranes.
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IKEGAMI SUSUMU, IMAYOSHI JUNJI, TAKAHASHI NOBUO, NAGANO HIROSHI. Dihydrofolate Reductase in Starfish Oocytes and Embryos: Developmental Consequences of Its Inhibition by Methotrexate1. (starfish/dihydrofolate reductase/methotrexate/DNA synthesis/early development). Dev Growth Differ 1985. [DOI: 10.1111/j.1440-169x.1985.00393.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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13
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Webber S, Whiteley JM. Comparative activity of rat liver dihydrofolate reductase with 7,8-dihydrofolate and other 7,8-dihydropteridines. Arch Biochem Biophys 1985; 236:681-90. [PMID: 3970530 DOI: 10.1016/0003-9861(85)90674-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The various interactions of rat liver dihydrofolate reductase with two unconjugated 7,8-dihydropteridines, 7,8-dihydrobiopterin and 6-methyl-7,8-dihydropteridine, have been compared with those of 7,8-dihydrofolate and folate. Of particular interest was the reactivity demonstrated by 7,8-dihydrobiopterin because of the potential physiological significance of this reaction both in the regeneration of tetrahydrobiopterin, a cofactor for various biological hydroxylations, and as a step in the biosynthesis of this compound from GTP. Kinetic experiments gave Km values of 0.17, 6.42, and 10.2 microM for 7,8-dihydrofolate, 7,8-dihydrobiopterin, and 6-methyl-7,8-dihydropteridine, respectively, with Vmax = 6.22, 2.39, and 1.54 mumol min-1 mg-1. With folate the enzyme showed high affinity (Km = 0.88 microM) but low Vmax (0.20 mumol min-1 mg-1). The natural cofactor was NADPH and a Km of approximately 0.7 microM was measured with each substrate. The enzyme was activated by both p-hydroxymercuribenzoate and urea when assayed with 7,8-dihydrofolate but was inhibited when 7,8-dihydrobiopterin was the substrate. The pH optimum for dihydrofolate reduction was 4 with enhancement at pH greater than or equal to 5.5 in the presence of 1 M NaCl. Peak activity with 7,8-dihydrobiopterin occurred at pH 4.8; this was shifted to pH 5.3 but was not enhanced by 1 M NaCl. Inhibition with methotrexate was similar whether the enzyme was assayed with either the conjugated or unconjugated 7,8-dihydro derivatives. The rat liver enzyme, highly unstable after purification, was stabilized in the presence of the nonionic detergent, Tween-20 (0.1%); however, the comparative properties toward the conjugated and unconjugated substrates were not altered by this treatment.
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14
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Kamen BA, Whyte-Bauer W, Bertino JR. A mechanism of resistance to methotrexate. NADPH but not NADH stimulation of methotrexate binding to dihydrofolate reductase. Biochem Pharmacol 1983; 32:1837-41. [PMID: 6882460 DOI: 10.1016/0006-2952(83)90047-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Characteristics of methotrexate (MTX) inhibition of dihydrofolic acid reductase (DHFR) enzyme activity and the effects of NADPH and NADH on enzyme-drug interaction were studied. Two highly sensitive assay procedures were used. The first utilized tritium-labeled MTX to measure direct binding properties of the enzyme and the second utilized tritium-labeled dihydrofolate (H2PteGlu) and folate (PteGlu) to analyze kinetics of reduction of these substrates. NADPH was found to enhance DHFR binding of MTX (Kd = 2.6 X 10(-11) M), whereas NADH was found to have no effect (Kd = 3.7 X 10(-9) M). However, NADH proved to be a good substrate for folate reduction compared to NADPH, especially in low salt buffer. The observation that NADH supports the reduction of folate and dihydrofolate but not MTX binding suggests that natural resistance to MTX could exist if NADH replaces NADPH as the main cofactor for DHFR.
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15
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Seng G, Bolard J. Circular dichroism studies in the near UV of ligand binding to chicken liver dihydrofolate reductase. Biochimie 1983; 65:169-75. [PMID: 6405809 DOI: 10.1016/s0300-9084(83)80081-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Circular dichroism spectra in the near UV (250-400 nm) were recorded for chicken liver dihydrofolate reductase and its complexes with substrates, inhibitor methotrexate, and cofactor NADPH. The spectra obtained with methotrexate are very like those published for bacterial dihydrofolate reductases. Thus we suggest that the conformations of methotrexate at the active site of the chicken liver enzyme and that of the enzyme from Lactobacillus casei which has been described extensively in X-ray studies show a great similarity. The same similarity does not hold in the case of the substrate dihydrofolate where the C.D. spectra of binary complexes obtained with enzymes from different sources are different.
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Fernandes DJ, Cardenas RM, Bertino JR, Hynes JB. Effects of 5,8-dideazaisopteroylglutamate and its possible tri-gamma-glutamyl metabolite (5,8-dideazaisoPteGlu3) on colon adenocarcinoma, and the folate dependent enzymes thymidylate synthase and dihydrofolate reductase. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1983; 163:341-57. [PMID: 6688493 DOI: 10.1007/978-1-4757-5241-0_25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A series of 2-amino-4-hydroxy-quinazolines was synthesized and evaluated as inhibitors of colon adenocarcinoma and the folate-dependent enzymes, thymidylate synthase and dihydrofolate reductase. Of the quinazolines tested, 5,8-dideazaisopteroylglutamate, (IAHQ), when administered at 85 mg/kg on days 2 and 10 after tumor implantation delayed the growth of colon tumor No. 38, and resulted in 6 of 20 tumor-free animals at 90 days. In contrast, methotrexate had no effect on the growth of colon tumor No. 38 at maximally tolerated doses. IAHQ was also active against human colon adenocarcinoma cells (HCT-8) in tissue culture, requiring a concentration of 5 X 10(-7) M to inhibit cell growth 50% after 72 hours continuous exposure. Since IAHQ was an effective substrate for folylpolyglutamate synthetase, we examined the effects of IAHQ and its possible tri-gamma-glutamyl metabolite, 5,8-dideazaisoPteGLu3, on thymidylate synthase and dihydrofolate reductase. Neither IAHQ nor 5,8-dideazaisoPteGlu3 stimulated significant binding of 5-fluorodeoxyuridylate to thymidylate synthase. This was consistent with the observation that IAHQ antagonized the killing of HCT-8 cells by 5-fluorouracil. 5,8 DideazaisoPteGlu3 bound more tightly to thymidylate synthase than dihydrofolate reductase as indicated by Kis of 0.09 and 0.7 microM when deoxyuridylate and dihydropteroylglutamate, respectively, were the variable substrates. Inhibition studies also revealed that binding of IAHQ and 5,8-dideazaisoPteGlu3 to thymidylate synthase is promoted and not antagonized by deoxyuridylate. The data suggests that the biochemical basis for the antitumor effects of IAHQ is the intracellular conversion of IAHQ to poly-gamma-glutamyl metabolites, which inhibit thymidylate synthase via formation of an inhibitor-deoxyuridylate-enzyme complex.
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Melera PW, Hession CA, Davide JP, Scotto KW, Biedler JL, Meyérs MB, Shanske S. Antifolate-resistant Chinese Hamster Cells. mRNA directed overproduction of multiple dihydrofolate reductases from a series of independently derived sublines containing amplified dihydrofolate reductase genes. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(18)33606-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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18
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Filman DJ, Bolin JT, Matthews DA, Kraut J. Crystal structures of Escherichia coli and Lactobacillus casei dihydrofolate reductase refined at 1.7 A resolution. II. Environment of bound NADPH and implications for catalysis. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(18)33498-7] [Citation(s) in RCA: 121] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Roth B, Cheng CC. Recent progress in the medicinal chemistry of 2,4-diaminopyrimidines. PROGRESS IN MEDICINAL CHEMISTRY 1982; 19:269-331. [PMID: 6129679 DOI: 10.1016/s0079-6468(08)70332-1] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Roberts GC, Feeney J, Burgen AS, Daluge S. The charge state of trimethoprim bound to Lactobacillus casei dihydrofolate reductase. FEBS Lett 1981; 131:85-8. [PMID: 6793401 DOI: 10.1016/0014-5793(81)80893-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Cocco L, Groff JP, Temple C, Montgomery JA, London RE, Matwiyoff NA, Blakley RL. Carbon-13 nuclear magnetic resonance study of protonation of methotrexate and aminopterin bound to dihydrofolate reductase. Biochemistry 1981; 20:3972-8. [PMID: 7284303 DOI: 10.1021/bi00517a005] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Methotrexate, aminopterin, and folate have been synthesized with 90% enrichment of C-2 with 13C. 13C nuclear magnetic resonance has been used to examine the state of protonation of the pteridine ring of these compounds under various conditions and gives much more clear-cut results than most other methods. For the free compounds the following pK values were obtained: methotrexate, 5.73 +/- 0.02 (N-1); aminopterin, 5.70 +/- 0.03 (N-1); folic acid, 2.40 (N-1) and 8.25 +/- 0.05 (N-3, O-4 amide group). The state of protonation of these compounds when complexed to dihydrofolate reductase (isoenzyme 2 from Streptococcus faecium) was also studied over the pH range 6--10. The resonance from bound methotrexate showed a constant chemical shift over the whole pH range studied, and it is inferred that in the complex the pteridine ring remains protonated to at least pH 10. The same result was obtained for the binary complex of aminopterin with the reductase and for either methotrexate or aminopterin in ternary complex with reductase and NADPH4. The latter is an inhibitor of the reductase competitive with NADPH. However, folate bound to the reductase in either the binary or the ternary complex shows the same protonation behavior as in the free state. The data indicate that the association constant for binding of methotrexate is increased enough when protonation of N-1 occurs to account for the enhanced binding of methotrexate as compared with folate.
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Cocco L, Temple C, Montgomery JA, London RE, Blakley RL. Protonation of methotrexate bound to the catalytic site of dihydrofolate from Lactobacillus casei. Biochem Biophys Res Commun 1981; 100:413-9. [PMID: 6789822 DOI: 10.1016/s0006-291x(81)80112-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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23
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Melera P, Wolgemuth D, Biedler J, Hession C. Antifolate-resistant chinese hamster cells. Evidence from independently derived sublines for the overproduction of two dihydrofolate reductases encoded by different mRNAs. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(19)86168-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Gready JE. Dihydrofolate reductase: binding of substrates and inhibitors and catalytic mechanism. ADVANCES IN PHARMACOLOGY AND CHEMOTHERAPY 1980; 17:37-102. [PMID: 7004143 DOI: 10.1016/s1054-3589(08)60007-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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25
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Hitchings GH, Smith SL. Dihydrofolate reductases as targets for inhibitors. ADVANCES IN ENZYME REGULATION 1980; 18:349-71. [PMID: 7446303 DOI: 10.1016/0065-2571(80)90025-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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26
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Smith S, Patrick P, Stone D, Phillips A, Burchall J. Porcine liver dihydrofolate reductase. Purification, properties, and amino acid sequence. J Biol Chem 1979. [DOI: 10.1016/s0021-9258(19)86510-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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27
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Bertino JR, Sawicki WL, Moroson BA, Cashmore AR, Elslager EF. 2,4-diamino-5-methyl-6-[(3,4,5-trimethoxyanilino)methyl]quinazoline (tmq), a potent non-classical folate antagonist inhibitor--I effect on dihydrofolate reductase and growth of rodent tumors in vitro and in vivo. Biochem Pharmacol 1979; 28:1983-7. [PMID: 454469 DOI: 10.1016/0006-2952(79)90655-5] [Citation(s) in RCA: 65] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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