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Phenylalanine Ammonia-Lyase: An enzyme that catalyzes the deamination of PHENYLALANINE to form trans-cinnamate and ammonia.Ammonia: A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.Anabaena variabilis: A species of ANABAENA that can form SPORES called akinetes.Histidine: An essential amino acid that is required for the production of HISTAMINE.Ammonia-Lyases: Enzymes that catalyze the formation of a carbon-carbon double bond by the elimination of AMMONIA. EC 4.3.1.Ethanolamine Ammonia-Lyase: An enzyme that catalyzes the deamination of ethanolamine to acetaldehyde. EC 4.3.1.7.p-Fluorophenylalanine: 3-(p-Fluorophenyl)-alanine.Aspartate Ammonia-Lyase: An enzyme that catalyzes the conversion of aspartic acid to ammonia and fumaric acid in plants and some microorganisms. EC 4.3.1.1.Rhodotorula: A red yeast-like mitosporic fungal genus generally regarded as nonpathogenic. It is cultured from numerous sources in human patients.Basidiomycota: A phylum of fungi that produce their sexual spores (basidiospores) on the outside of the basidium. It includes forms commonly known as mushrooms, boletes, puffballs, earthstars, stinkhorns, bird's-nest fungi, jelly fungi, bracket or shelf fungi, and rust and smut fungi.Salicylic Acid: A compound obtained from the bark of the white willow and wintergreen leaves. It has bacteriostatic, fungicidal, and keratolytic actions.ATP Citrate (pro-S)-Lyase: An enzyme that, in the presence of ATP and COENZYME A, catalyzes the cleavage of citrate to yield acetyl CoA, oxaloacetate, ADP, and ORTHOPHOSPHATE. This reaction represents an important step in fatty acid biosynthesis. This enzyme was formerly listed as EC 4.1.3.8.PhenylpropionatesPlant Diseases: Diseases of plants.Plant Leaves: Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)Histidine Decarboxylase: An enzyme that catalyzes the decarboxylation of histidine to histamine and carbon dioxide. It requires pyridoxal phosphate in animal tissues, but not in microorganisms. EC 4.1.1.22.Phenylalanine: An essential aromatic amino acid that is a precursor of MELANIN; DOPAMINE; noradrenalin (NOREPINEPHRINE), and THYROXINE.Phenols: Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.Gene Expression Regulation, Plant: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.Plant Proteins: Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.Polysaccharide-Lyases: A group of carbon-oxygen lyases. These enzymes catalyze the breakage of a carbon-oxygen bond in polysaccharides leading to an unsaturated product and the elimination of an alcohol. EC 4.2.2.Adenylosuccinate Lyase: An enzyme that, in the course of purine ribonucleotide biosynthesis, catalyzes the conversion of 5'-phosphoribosyl-4-(N-succinocarboxamide)-5-aminoimidazole to 5'-phosphoribosyl-4-carboxamide-5-aminoimidazole and the conversion of adenylosuccinic acid to AMP. EC 4.3.2.2.Diethyl Pyrocarbonate: Preservative for wines, soft drinks, and fruit juices and a gentle esterifying agent.Oxo-Acid-Lyases: Enzymes that catalyze the cleavage of a carbon-carbon bond of a 3-hydroxy acid. (Dorland, 28th ed) EC 4.1.3.Histidine Ammonia-Lyase: An enzyme that catalyzes the first step of histidine catabolism, forming UROCANIC ACID and AMMONIA from HISTIDINE. Deficiency of this enzyme is associated with elevated levels of serum histidine and is called histidinemia (AMINO ACID METABOLISM, INBORN ERRORS).Lyases: A class of enzymes that catalyze the cleavage of C-C, C-O, and C-N, and other bonds by other means than by hydrolysis or oxidation. (Enzyme Nomenclature, 1992) EC 4.Aldehyde-Lyases: Enzymes that catalyze a reverse aldol condensation. A molecule containing a hydroxyl group and a carbonyl group is cleaved at a C-C bond to produce two smaller molecules (ALDEHYDES or KETONES). EC 4.1.2.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Nitrogen: An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Amino Acids: Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.Kinetics: The rate dynamics in chemical or physical systems.Glutamine: A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from GLUTAMIC ACID and AMMONIA. It is the principal carrier of NITROGEN in the body and is an important energy source for many cells.Nitrosomonas: A genus of gram-negative, ellipsoidal or rod-shaped bacteria whose major source of energy and reducing power is from the oxidation of ammonia to nitrite. Its species occur in soils, oceans, lakes, rivers, and sewage disposal systems.Urea: A compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids.Carbamoyl-Phosphate Synthase (Ammonia): An enzyme that catalyzes the formation of carbamoyl phosphate from ATP, carbon dioxide, and ammonia. This enzyme is specific for arginine biosynthesis or the urea cycle. Absence or lack of this enzyme may cause CARBAMOYL-PHOSPHATE SYNTHASE I DEFICIENCY DISEASE. EC 6.3.4.16.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Hyperammonemia: Elevated level of AMMONIA in the blood. It is a sign of defective CATABOLISM of AMINO ACIDS or ammonia to UREA.Glutamate-Ammonia Ligase: An enzyme that catalyzes the conversion of ATP, L-glutamate, and NH3 to ADP, orthophosphate, and L-glutamine. It also acts more slowly on 4-methylene-L-glutamate. (From Enzyme Nomenclature, 1992) EC 6.3.1.2.Bacterial Proteins: Proteins found in any species of bacterium.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.Steroid 17-alpha-Hydroxylase: A microsomal cytochrome P450 enzyme that catalyzes the 17-alpha-hydroxylation of progesterone or pregnenolone and subsequent cleavage of the residual two carbons at C17 in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP17 gene, generates precursors for glucocorticoid, androgen, and estrogen synthesis. Defects in CYP17 gene cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL) and abnormal sexual differentiation.Ammonium Chloride: An acidifying agent that has expectorant and diuretic effects. Also used in etching and batteries and as a flux in electroplating.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Nitrogen Radioisotopes: Unstable isotopes of nitrogen that decay or disintegrate emitting radiation. N atoms with atomic weights 12, 13, 16, 17, and 18 are radioactive nitrogen isotopes.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Nitrification: A process facilitated by specialized bacteria involving the oxidation of ammonium to nitrite and nitrate.Catalysis: The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Protein Kinases: A family of enzymes that catalyze the conversion of ATP and a protein to ADP and a phosphoprotein.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.ATP Phosphoribosyltransferase: An enzyme that catalyzes the first step of the pathway for histidine biosynthesis in Salmonella typhimurium. ATP reacts reversibly with 5-phosphoribosyl-1-pyrophosphate to yield N-1-(5'-phosphoribosyl)-ATP and pyrophosphate. EC 2.4.2.17.Histidinol: The penultimate step in the pathway of histidine biosynthesis. Oxidation of the alcohol group on the side chain gives the acid group forming histidine. Histidinol has also been used as an inhibitor of protein synthesis.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Urocanate Hydratase: An enzyme that catalyzes the conversion of 4,5-dihydro-4-oxo-5-imidazolepropanoate to urocanate and water. EC 4.2.1.49.Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).DNA-(Apurinic or Apyrimidinic Site) Lyase: A DNA repair enzyme that catalyses the excision of ribose residues at apurinic and apyrimidinic DNA sites that can result from the action of DNA GLYCOSYLASES. The enzyme catalyzes a beta-elimination reaction in which the C-O-P bond 3' to the apurinic or apyrimidinic site in DNA is broken, leaving a 3'-terminal unsaturated sugar and a product with a terminal 5'-phosphate. This enzyme was previously listed under EC 3.1.25.2.Amidine-Lyases: These enzymes catalyze the elimination of ammonia from amidines with the formation of a double bond. EC 4.3.2.GlyoxylatesCrystallography, X-Ray: The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Pectins: High molecular weight polysaccharides present in the cell walls of all plants. Pectins cement cell walls together. They are used as emulsifiers and stabilizers in the food industry. They have been tried for a variety of therapeutic uses including as antidiarrheals, where they are now generally considered ineffective, and in the treatment of hypercholesterolemia.Recombinant Proteins: Proteins prepared by recombinant DNA technology.