The enzyme catalyzing the formation of orotidine-5'-phosphoric acid (orotidylic acid) from orotic acid and 5-phosphoribosyl-1-pyrophosphate in the course of pyrimidine nucleotide biosynthesis. EC
Orotidine-5'-phosphate carboxy-lyase. Catalyzes the decarboxylation of orotidylic acid to yield uridylic acid in the final step of the pyrimidine nucleotide biosynthesis pathway. EC
Enzymes of the transferase class that catalyze the transfer of a pentose group from one compound to another.
The key substance in the biosynthesis of histidine, tryptophan, and purine and pyrimidine nucleotides.
An enzyme that in the course of pyrimidine biosynthesis, catalyzes the oxidation of dihydro-orotic acid to orotic acid utilizing oxygen as the electron acceptor. This enzyme is a flavoprotein which contains both FLAVIN-ADENINE DINUCLEOTIDE and FLAVIN MONONUCLEOTIDE as well as iron-sulfur centers. EC
An enzyme that catalyzes the conversion of 5-phosphoribosyl-1-pyrophosphate and hypoxanthine, guanine, or 6-mercaptopurine to the corresponding 5'-mononucleotides and pyrophosphate. The enzyme is important in purine biosynthesis as well as central nervous system functions. Complete lack of enzyme activity is associated with the LESCH-NYHAN SYNDROME, while partial deficiency results in overproduction of uric acid. EC
A triazine nucleoside used as an antineoplastic antimetabolite. It interferes with pyrimidine biosynthesis thereby preventing formation of cellular nucleic acids. As the triacetate, it is also effective as an antipsoriatic.
An enzyme catalyzing the formation of AMP from adenine and phosphoribosylpyrophosphate. It can act as a salvage enzyme for recycling of adenine into nucleic acids. EC
An enzyme that catalyzes the transfer of ribose from uridine to orthophosphate, forming uracil and ribose 1-phosphate.
Enzymes that catalyze the addition of a carboxyl group to a compound (carboxylases) or the removal of a carboxyl group from a compound (decarboxylases). EC 4.1.1.
An enzyme that, in the course of pyrimidine biosynthesis, catalyzes ring closure by removal of water from N-carbamoylaspartate to yield dihydro-orotic acid. EC
An enzyme that catalyzes the conversion of carbamoyl phosphate and L-aspartate to yield orthophosphate and N-carbamoyl-L-aspartate. (From Enzyme Nomenclature, 1992) EC
An enzyme that catalyzes the formation of nicotinamide mononucleotide (NMN) from nicotinamide and 5-phosphoribosyl-1-pyrophosphate, the rate-limiting step in the biosynthesis of the NAD coenzyme. It is also known as a growth factor for early B-LYMPHOCYTES, or an ADIPOKINE with insulin-mimetic effects (visfatin).
An inherited disorder transmitted as a sex-linked trait and caused by a deficiency of an enzyme of purine metabolism; HYPOXANTHINE PHOSPHORIBOSYLTRANSFERASE. Affected individuals are normal in the first year of life and then develop psychomotor retardation, extrapyramidal movement disorders, progressive spasticity, and seizures. Self-destructive behaviors such as biting of fingers and lips are seen frequently. Intellectual impairment may also occur but is typically not severe. Elevation of uric acid in the serum leads to the development of renal calculi and gouty arthritis. (Menkes, Textbook of Child Neurology, 5th ed, pp127)
A family of 6-membered heterocyclic compounds occurring in nature in a wide variety of forms. They include several nucleic acid constituents (CYTOSINE; THYMINE; and URACIL) and form the basic structure of the barbiturates.
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
Purine bases related to hypoxanthine, an intermediate product of uric acid synthesis and a breakdown product of adenine catabolism.
An enzyme that catalyzes the formation of N-5'-phosphoribosylanthranilic acid from anthranilate and phosphoribosylpyrophosphate, the first step in tryptophan synthesis in E. coli. It exists in a complex with ANTHRANILATE SYNTHASE in bacteria. EC
An oxidoreductase involved in pyrimidine base degradation. It catalyzes the catabolism of THYMINE; URACIL and the chemotherapeutic drug, 5-FLUOROURACIL.
An enzyme of the transferase class that catalyzes the reaction 5,10-methylenetetrahydrofolate and dUMP to dihydrofolate and dTMP in the synthesis of thymidine triphosphate. (From Dorland, 27th ed) EC
An autosomal recessive disorder affecting DIHYDROPYRIMIDINE DEHYDROGENASE and causing familial pyrimidinemia. It is characterized by thymine-uraciluria in homozygous deficient patients. Even a partial deficiency in the enzyme leaves individuals at risk for developing severe 5-FLUOROURACIL-associated toxicity.
An enzyme of the lyase class that catalyzes the cleavage of fructose 1,6-biphosphate to form dihydroxyacetone phosphate and glyceraldehyde 3-phosphate. The enzyme also acts on (3S,4R)-ketose 1-phosphates. The yeast and bacterial enzymes are zinc proteins. (Enzyme Nomenclature, 1992) E.C.
The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Chemical compounds derived from acids by the elimination of a molecule of water.
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
Contractile tissue that produces movement in animals.
All of the divisions of the natural sciences dealing with the various aspects of the phenomena of life and vital processes. The concept includes anatomy and physiology, biochemistry and biophysics, and the biology of animals, plants, and microorganisms. It should be differentiated from BIOLOGY, one of its subdivisions, concerned specifically with the origin and life processes of living organisms.
A publication issued at stated, more or less regular, intervals.
A bibliographic database that includes MEDLINE as its primary subset. It is produced by the National Center for Biotechnology Information (NCBI), part of the NATIONAL LIBRARY OF MEDICINE. PubMed, which is searchable through NLM's Web site, also includes access to additional citations to selected life sciences journals not in MEDLINE, and links to other resources such as the full-text of articles at participating publishers' Web sites, NCBI's molecular biology databases, and PubMed Central.
A phylum of unicellular parasitic EUKARYOTES characterized by the presence of complex apical organelles generally consisting of a conoid that aids in penetrating host cells, rhoptries that possibly secrete a proteolytic enzyme, and subpellicular microtubules that may be related to motility.
Lists of persons or organizations, systematically arranged, usually in alphabetic or classed order, giving address, affiliations, etc., for individuals, and giving address, officers, functions, and similar data for organizations. (ALA Glossary of Library and Information Science, 1983)
A genus of ascomycetous fungi of the family Saccharomycetaceae, order SACCHAROMYCETALES.
A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.
Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.
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.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide 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.
Proteins found in any species of fungus.