Chemistry and Biology of Pteridines and Folates

Making Methionine: A Love Affair with Folate.- Structure Elucidations of Dimeric Pteridines.- A Selective Procedure for 6-Subsituted Pterin Derivatives: Synthesis and Substitution of Pterin 6-Triflate.- Solution and Solid Phase Synthesis of Pteridines, Purines and Related Compounds.- Synthesis of Pteridines with C-2 and C-6 Functional Group Diversity.- Stereospecific Synthesis of 2-Desamino-Tetrahydropterins as Probes of Hydroxylase Cofactor Recognition.- New Pyranopterin Chemistry Related to Molybdenum and Tungsten Enzymes.- Application of FDCD Spectroscopy for Determination of Chiralities of Biologically Important Pteridines.- Photo-Oxidation of Sepiapterin Produces Pterin-6-Carboxylic Acid and H2O2In Vitro.- Regulation of Tyrosine Hydroxylase by S-Glutathiolation: Relevance to Conditions Associated with Dopamine Neuronal Damage.- The Conformation of Tetrahydro-Biopterin Free and Bound to Aromatic Amino Acid Hydroxylases and NOS.- Regulatory Properties of the Tetrahydropterin Cofactor in the Reaction Catalyzed by Human Tyrosine Hydroxylase Isoforms 1-4.- Structure and Regulation of Phenylalanine Hydroxylase, and Implications for Related Enzymes.- Interaction of Phosphorylated Tyrosine Hydroxylase with 14-3-3 Proteins: Effects on Phosphorylation Kinetics.- Mechanistic Studies of Tryptophan Hydroxylase.- Role of Phe313/Trp326 in Determining Substrate Specificity in Tryptophan and Phenylalanine Hydroxylases.- Possible Contributions of Labile Asparagine Residues to Differences in Regulatory Properties of Human and Rat Phenylalanine Hydroxylase.- 3-(2-Thienyl)-L-Alanine as a Competitive Substrate Analogue and Activator of Human Phenylalanine Hydroxylase.- The N-Terminus of Human Tyrosine Hydroxylase is Responsible for its Association with Phospholipid Bilayers.- Mechanisms of Tyrosine Hydroxylase Activation by Stress Activated Protein Kinases.- Substrate Specificities of Phenylalanine and Tyrosine Hydroxylase: Role of Aspartate 425 of Tyrosine Hydroxylase.- Mutation of W457 Alters N-Hydroxy-L-Arginine Oxidation by Inducible NO Synthase: A Single Turnover Study.- Regulation of Rat Hepatic Phenylalanine Hydroxylating System In Vivo.- Estradiol Modulates GTP Cyclohydrolase I Gene Expression in Brain Catecholaminergic Systems.- PKC-Mediated Regulation of GTP Cyclohydrolase I in Mast Cells and Renal Mesangial Cells.- Regulation of GTP Cyclohydrolase I by Estrogen.- Sexually Dimorphic GTP Cyclohydrolase I Gene Expression is Independent of Sex Hormones.- Studies on the Reaction Mechanism of GTP Cyclohydrolase I.- Site-Directed Mutagenesis of Residues in the Active Site of Sepiapterin Reductase.- Determination of Residues Of Sepiapterin Reductase Phosphorylated by Ca2+/Calmodulin-Dependent Protein Kinase II.- The Interaction of GTP Cyclohydrolase I and GTP Cyclohydrolase Feedback Regulatory Protein Can be Detected Using the Yeast Two-Hybrid System.- Co-Induction of Tetrahydrobiopterin and Catecholamine Syntheses in V-1-Overexpressing PC12D Cells.- Sepiapterin Administration Raises Tissue BH4 Levels More Efficiently than BH4 Supplement in Normal Mice.- Cells Take up BH4, Oxidize it, and the Oxidized Biopterin is Preferentially Released.- Catecholamines-Up, a Negative Regulator of Tyrosine Hydroxylase and GTP Cyclohydrolase I in Drosophila Melanogaster.- The Pteridine Pathway in the Zebrafish, Danio Rerio: Development in Neural Crest-Derived Cells and its Control by GTP Cyclohydrolase I.- Pteridine and Nitric Oxide Biosynthesis in Physarum Polycephalum.- Pteridines and Pigment Granules of Wing Scales Concerned with Sexual Difference in Wing's Capability Reflecting Near-UV Rays in the Japanese Cabbage Butterfly, Pieris Rapae Crucibora.- Tetrahydrobiopterin, Nitric Oxide Synthesis and cGMP Concentrations in Mutants of Physarum Polycephalum with Altered Sporulation Behavior.- BH4 and NOS are Involved in Light Controlled Development of Sporangiophores in the Fungus Phycomyces Blakesleeanus.- Determination of Tetrahydropterins as Native Pteridines in Two Microorganisms, Tetrahymena Pyriformis and E. coli.- Identification of the Sulfurtransfer Pathway for the Generation of the Dithiolene Moiety of Molybdopterin in Escherichia Coli.- Tetrahydrobiopterin and Vascular Endothelial Function.- L-Ascorbic Acid Increases Intracellular Tetrahydrobiopterin Via a Chemical Stabilization and Potentiates Nitric Oxide Synthesis in Endothelial Cells.- The Redox Status of Bound Pterin Cofactor Determines Whether eNOS Produces NO or Superoxide Anion: [3H]-BH4 Binding Studies Provide Insights into Vascular Pathophysiology.- Sepiapterin Reductase Deficiency: Molecular Analysis in a New Case Presenting with Neurotransmitter Deficiency Without Hyperphenylalaninemia.- Molecular Basis of DOPA-Responsive Dystonia.- Human Nigrostriatal Dopamine Neurons Express Low Levels of GTP Cyclohydrolase I mRNA.- Immunosuppressive Effects of the 4-Amino Analogue of Tetrahydrobiopterin.- Tetrahydrobiopterin Responsive Hyperphenylalaninemia Without Biopterin Deficiency.- The Fate of Intravenously Administered Tetrahydrobiopterin and its Implications for Heterologous Gene Therapy of Phenylketonuria.- Influence of Hydrogen Peroxide (H2O2) on Pterin Homeostasis in the Depigmentation Disorder Vitiligo.- Catechol-O-Methyltransferase Inhibition in the Treatment of Tetrahydrobiopterin Deficiency.- Changes in Dihydropteridine Reductase (DHPR) Activity of the Occupationally Lead Exposed Workers.- Clinical Utility of Pteridine Measurement in Cerebrospinal Fluid.- Effect of Ascorbic Acid in Measurement of Serum Pteridine Concentration.- The Effect of Tetrahydrobiopterin (BH4) on Sperm Motility.- Tetrahydrobiopterin Deficiency in Diabetic Rats.- The Effect of Tetrahydrobiopterin (BH4) on Diabetic Nephropathy in Streptozotocin (Stz) Induced Diabetic Rats.- Determination of Sepiapterin and Sepiapterin Reductase in Human Skin.- Neopterin, an Immunodiagnostic and Oxidative Stress Indicator.- Role of Neopterin in Immune Monitoring in Transplant Medicine.- Neopterin and 7,8-Dihydroneopterin-Induced Signal Transduction Cascades in Cell Lines.- Determination of Neopterin Levels in Gingival Crevicular Fluid (GCF).- Neopterin and Biopterin Levels in Pregnancy.- Tetrahyrdobiopterin (BH4)-Mediated Neuronal Death Following Intrastriatal Kainic Acid: Implications for Parkinson's Disease.- Inhibition of Oxidative Stress During Developmental Cell Death: Cellular and Behavioral Effects.- The Role of Tetrahydrobiopterin (BH4) in Trophic Factor Withdrawal-Induced Apoptosis in PC12 Cells.- Apoptotic Death of PC12 Cells Induced by Ischemia-Like Conditions is Mediated by Tetrahydrobiopterin (BH4) Metabolism.- New Approaches Towards Inhibitors of Folate-Dependent Enzymes: Rapid Synthesis of 5-Deazapterins from Uracil Derivatives.- Solid and Solution Phase Strategies for the Synthesis of Potential Inhibitors of Folate Biosynthesis.- Progress Towards the Synthesis of Pyrimidodiazepine-Based Folates as Potential Inhibitors of Glycinamide Ribonucleotide Formyltransferase.- Role of P53 Status on Sensitivity to Thymidylate Synthase Inhibitors and Induction of Apoptosis.- Synthesis of N-[4-[(2-Amino-6-Methyl-3,4-Dihydro-4-Oxo-7h-Pyrrolo[2,3-D]-Pyrimidin-5-YI)Methyl]Benzoyl]-L-Glutamic Acid as an Antifolate.- Effect of Bridge Truncation of Classical 2,4-Diamino-5-Substituted Furo [2,3-D]Pyrimidine and 2-Amino-4-Oxo-6-Substituted Pyrrolo[2,3-D]Pyrimidine on Antifolate Activity.- Selection of Methotrexate-Resistant Lactobacillus Casei in the Presence of Folate or 5-Formyl-Tetrahydrofolate Affects the Resistance Mechanism.- Molecular Mechanisms of Resistance to Antimalarial Antifolate Drug Pyrimethamine-Sulfadoxine.- 5-Fluorouracil Induction of Fas and Apoptosis in Colon Cancer Patients: Relation of Clinical Outcome with Thymidylate Synthase, McI-1 and Rb.- Synthesis of 2- or 4-Seleno Analogues of dUMP and FdUMP, and the Corresponding Nucleosides. Interactions with Mammalian Tumor Thymidylate Synthase of the Selenonucleotides and Inhibition of Tumor Cell Growth by the Selenonucleosides.- Induction of Resistance to the Multi-Targeted antifolate MTA (Ly231514) in Widr Human Colon Cancer Cells.- Mutational Studies of an Essential Glutamate Residue in Escherichia coli Folylpolyglutamate Synthetase with a Role in ATP Binding.- Rapid Purification of the T-Protein of the Glycine Cleavage System from Rabbit Liver.- Effects of Cellular Glycine on Cell Proliferation.- Microarray Analysis of Genes Induced by Methionine Starvation and Growth on Different Sulfur Sources in Yeast.- Gene Structure and Expression of Trichinella spiralis Thymidylate Synthase.- Lack of Mutation of L1210 Thymidylate Synthase with Altered Sensitivity to FdUMP Inhibition.- Enzymes of Thymidylate Biosynthesis in Trichinella pseudospiralis Muscle Larvae and Caenorhabditis elegans Dauer Larvae.- Thymidylate Synthase Heterogeneity Assessed by Monoclonal Antibodies.- Structure-Based Modeling of Reversed N9-C10 Bridge Antifols with Human, Pc and Tg DHFR.- Regulation of Mammalian Methionine Synthase by B12.- Biochemical Studies of Human Methionine Synthase Reductase.- Model Studies for the B12 Dependent Methyltransferases.- Betaine-Homocysteine S-Methyl-Transferase (BHMT) Transcription is Inhibited by S-Adenosylmethionine (AdoMet).- Can Elevated Plasma Homocysteine Levels Result in the Inhibition of Intracellular Methyltransferases?.- The Neuropathy of Disturbed Brain Methylation Reactions.- Dopamine-Stimulated Solid-State Signaling: A Novel Role for Single-Carbon Folates in Human Attention.- Is Moderate Hyperhomocysteinemia Due to Folic Acid Depletion Rather than Insufficient Dietary Intake?.- C677t MTHFR Genotype is a Risk Factor for Thromboembolism: Comparison of T Allele Frequency and Homocysteine Level Between Female Thromboembolic and Non-Thromboembolic Vascular Patients, NTD Mothers and Matched NTD Controls.- Molecular Bases of Hyper-Homocysteinemia Due to Inborn Errors of Folate and Cobalamin Metabolism.- Vitamin B6 (PLP) and Neural Tube Defects: Is There an Association?.- Erythrocyte Folate Levels in Operating Room Personnel.- A Human Ileostomy Model to Determine Folate Bioavailability From Food.- 12 Channel Coulometric Electrochemical Detection for the Identification of Polyglutamate Homology Amongst Cellular Folates.- Gastro-Intestinal pH Modulates Facile Interconvertion of Native Formylfolates During Absorption.- Control Of Folate Production in Lactic Acid Bacteria by Using Metabolic Engineering.- Evidence for a Cryptic Gene that Enables E. coli to Specifically Transport Folate Analogs.- Folate Transport Abnormalities and Congenital Defects.- Role of Multidrug Resistance Proteins (MRP) in Resistance to Antifolates and Folate Homeostasis.- Kinetics Of Reduced Folate Carrier- and Membrane-Associated Folate Receptor-Mediated Transport of Antifolates.- Cell Biology and Regulation of the Intestinal Folate Absorption Process.- Participants.