3-Hydroxyanthranilic Acid: An oxidation product of tryptophan metabolism. It may be a free radical scavenger and a carcinogen.3-Hydroxyanthranilate 3,4-Dioxygenase: An enzyme that catalyzes the conversion of 3-hydroxyanthranilate to 2-amino-3-carboxymuconate semialdehyde. It was formerly characterized as EC 1.13.1.6.ortho-Aminobenzoates: Benzoic acids, salts, or esters that contain an amino group attached to carbon number 2 or 6 of the benzene ring structure.KynurenineOxazines: Six-membered heterocycles containing an oxygen and a nitrogen.Streptomyces antibioticus: An actinomycete from which the antibiotic OLEANDOMYCIN is obtained.XanthurenatesTryptophan: An essential amino acid that is necessary for normal growth in infants and for NITROGEN balance in adults. It is a precursor of INDOLE ALKALOIDS in plants. It is a precursor of SEROTONIN (hence its use as an antidepressant and sleep aid). It can be a precursor to NIACIN, albeit inefficiently, in mammals.Niacin: A water-soluble vitamin of the B complex occurring in various animal and plant tissues. It is required by the body for the formation of coenzymes NAD and NADP. It has PELLAGRA-curative, vasodilating, and antilipemic properties.Quinolinic Acid: A metabolite of tryptophan with a possible role in neurodegenerative disorders. Elevated CSF levels of quinolinic acid are correlated with the severity of neuropsychological deficits in patients who have AIDS.Oxygenases: Oxidases that specifically introduce DIOXYGEN-derived oxygen atoms into a variety of organic molecules.Indoleamine-Pyrrole 2,3,-Dioxygenase: A dioxygenase with specificity for the oxidation of the indoleamine ring of TRYPTOPHAN. It is an extrahepatic enzyme that plays a role in metabolism as the first and rate limiting enzyme in the kynurenine pathway of TRYPTOPHAN catabolism.Dioxygenases: Non-heme iron-containing enzymes that incorporate two atoms of OXYGEN into the substrate. They are important in biosynthesis of FLAVONOIDS; GIBBERELLINS; and HYOSCYAMINE; and for degradation of AROMATIC HYDROCARBONS.Streptomyces: A genus of bacteria that form a nonfragmented aerial mycelium. Many species have been identified with some being pathogenic. This genus is responsible for producing a majority of the ANTI-BACTERIAL AGENTS of practical value.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.Free Radical Scavengers: Substances that influence the course of a chemical reaction by ready combination with free radicals. Among other effects, this combining activity protects pancreatic islets against damage by cytokines and prevents myocardial and pulmonary perfusion injuries.Chromatography, Thin Layer: Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Quinolinic AcidsCorpus Striatum: Striped GRAY MATTER and WHITE MATTER consisting of the NEOSTRIATUM and paleostriatum (GLOBUS PALLIDUS). It is located in front of and lateral to the THALAMUS in each cerebral hemisphere. The gray substance is made up of the CAUDATE NUCLEUS and the lentiform nucleus (the latter consisting of the GLOBUS PALLIDUS and PUTAMEN). The WHITE MATTER is the INTERNAL CAPSULE.Dictionaries, MedicalInflammation: A pathological process characterized by injury or destruction of tissues caused by a variety of cytologic and chemical reactions. It is usually manifested by typical signs of pain, heat, redness, swelling, and loss of function.Immunity, Innate: The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from the presence of naturally occurring ANTI-INFECTIVE AGENTS, constitutional factors such as BODY TEMPERATURE and immediate acting immune cells such as NATURAL KILLER CELLS.T-Lymphocytes, Regulatory: CD4-positive T cells that inhibit immunopathology or autoimmune disease in vivo. They inhibit the immune response by influencing the activity of other cell types. Regulatory T-cells include naturally occurring CD4+CD25+ cells, IL-10 secreting Tr1 cells, and Th3 cells.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.Fungi: A kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including MUSHROOMS; YEASTS; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies.Th2 Cells: Subset of helper-inducer T-lymphocytes which synthesize and secrete the interleukins IL-4, IL-5, IL-6, and IL-10. These cytokines influence B-cell development and antibody production as well as augmenting humoral responses.Acetylserotonin O-Methyltransferase: An enzyme that catalyzes the transfer of a methyl group from S-adenosylmethionine to N-acetylserotonin to form N-acetyl-5-methoxytryptamine (MELATONIN).Kynurenic Acid: A broad-spectrum excitatory amino acid antagonist used as a research tool.Fas-Associated Death Domain Protein: A signal-transducing adaptor protein that associates with TNF RECEPTOR complexes. It contains a death effector domain that can interact with death effector domains found on INITIATOR CASPASES such as CASPASE 8 and CASPASE 10. Activation of CASPASES via interaction with this protein plays a role in the signaling cascade that leads to APOPTOSIS.Apoptosis: One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.Caspases: A family of intracellular CYSTEINE ENDOPEPTIDASES that play a role in regulating INFLAMMATION and APOPTOSIS. They specifically cleave peptides at a CYSTEINE amino acid that follows an ASPARTIC ACID residue. Caspases are activated by proteolytic cleavage of a precursor form to yield large and small subunits that form the enzyme. Since the cleavage site within precursors matches the specificity of caspases, sequential activation of precursors by activated caspases can occur.Caspase 8: A long pro-domain caspase that contains a death effector domain in its pro-domain region. Caspase 8 plays a role in APOPTOSIS by cleaving and activating EFFECTOR CASPASES. Activation of this enzyme can occur via the interaction of its N-terminal death effector domain with DEATH DOMAIN RECEPTOR SIGNALING ADAPTOR PROTEINS.Antigens, CD95: A tumor necrosis factor receptor subtype found in a variety of tissues and on activated LYMPHOCYTES. It has specificity for FAS LIGAND and plays a role in regulation of peripheral immune responses and APOPTOSIS. Multiple isoforms of the protein exist due to multiple ALTERNATIVE SPLICING. The activated receptor signals via a conserved death domain that associates with specific TNF RECEPTOR-ASSOCIATED FACTORS in the CYTOPLASM.Fas Ligand Protein: A transmembrane protein belonging to the tumor necrosis factor superfamily that was originally discovered on cells of the lymphoid-myeloid lineage, including activated T-LYMPHOCYTES and NATURAL KILLER CELLS. It plays an important role in immune homeostasis and cell-mediated toxicity by binding to the FAS RECEPTOR and triggering APOPTOSIS.Caspase 3: A short pro-domain caspase that plays an effector role in APOPTOSIS. It is activated by INITIATOR CASPASES such as CASPASE 9. Isoforms of this protein exist due to multiple alternative splicing of its MESSENGER RNA.International Cooperation: The interaction of persons or groups of persons representing various nations in the pursuit of a common goal or interest.Intracranial Aneurysm: Abnormal outpouching in the wall of intracranial blood vessels. Most common are the saccular (berry) aneurysms located at branch points in CIRCLE OF WILLIS at the base of the brain. Vessel rupture results in SUBARACHNOID HEMORRHAGE or INTRACRANIAL HEMORRHAGES. Giant aneurysms (>2.5 cm in diameter) may compress adjacent structures, including the OCULOMOTOR NERVE. (From Adams et al., Principles of Neurology, 6th ed, p841)Aneurysm: Pathological outpouching or sac-like dilatation in the wall of any blood vessel (ARTERIES or VEINS) or the heart (HEART ANEURYSM). It indicates a thin and weakened area in the wall which may later rupture. Aneurysms are classified by location, etiology, or other characteristics.Registries: The systems and processes involved in the establishment, support, management, and operation of registers, e.g., disease registers.Aneurysm, Infected: Aneurysm due to growth of microorganisms in the arterial wall, or infection arising within preexisting arteriosclerotic aneurysms.Hypermedia: Computerized compilations of information units (text, sound, graphics, and/or video) interconnected by logical nonlinear linkages that enable users to follow optimal paths through the material and also the systems used to create and display this information. (From Thesaurus of ERIC Descriptors, 1994)Genetic Linkage: The co-inheritance of two or more non-allelic GENES due to their being located more or less closely on the same CHROMOSOME.Cryptococcus gattii: A species of the fungus CRYPTOCOCCUS. Its teleomorph is Filobasidiella bacillispora.Cryptococcus neoformans: A species of the fungus CRYPTOCOCCUS. Its teleomorph is Filobasidiella neoformans.Cryptococcus: A mitosporic Tremellales fungal genus whose species usually have a capsule and do not form pseudomycellium. Teleomorphs include Filobasidiella and Fidobasidium.Cryptococcosis: Infection with a fungus of the species CRYPTOCOCCUS NEOFORMANS.D-Amino-Acid OxidaseCandida albicans: A unicellular budding fungus which is the principal pathogenic species causing CANDIDIASIS (moniliasis).Gastrointestinal Tract: Generally refers to the digestive structures stretching from the MOUTH to ANUS, but does not include the accessory glandular organs (LIVER; BILIARY TRACT; PANCREAS).Metagenome: A collective genome representative of the many organisms, primarily microorganisms, existing in a community.Microbiota: The full collection of microbes (bacteria, fungi, virus, etc.) that naturally exist within a particular biological niche such as an organism, soil, a body of water, etc.Intestines: The section of the alimentary canal from the STOMACH to the ANAL CANAL. It includes the LARGE INTESTINE and SMALL INTESTINE.Receptors, Aryl Hydrocarbon: Cytoplasmic proteins that bind certain aryl hydrocarbons, translocate to the nucleus, and activate transcription of particular DNA segments. AH receptors are identified by their high-affinity binding to several carcinogenic or teratogenic environmental chemicals including polycyclic aromatic hydrocarbons found in cigarette smoke and smog, heterocyclic amines found in cooked foods, and halogenated hydrocarbons including dioxins and polychlorinated biphenyls. No endogenous ligand has been identified, but an unknown natural messenger with a role in cell differentiation and development is suspected.Skatole

Influence of adenine-induced renal failure on tryptophan-niacin metabolism in rats. (1/40)

To discover the role of the kidney in tryptophan degradation, especially tryptophan to niacin, rat kidneys were injured by feeding a diet containing a large amount of adenine. The kidney contains very high activity of aminocarboxymuconate-semialdehyde decarboxylase (ACMSD), which leads tryptophan into the glutaric acid pathway and then the TCA cycle, but not to the niacin pathway. On the other hand, kidneys contain significant activity of quinolinate phosphoribosyltransferase (QPRT), which leads tryptophan into the niacin pathway. The ACMSD activity in kidneys were significantly lower in the adenine group than in the control group, while the QPRT activity was almost the same, however, the formations of niacin and its compounds such as N1-methylnicotinamide and its pyridones did not increase, and therefore, the conversion ratio of tryptophan to niacin was lower in the adenine group than in the control group. The contents of NAD and NADP in liver, kidney, and blood were also lower in the adenine group. The decreased levels of niacin and the related compounds were consistent with the changes in the enzyme activities involved in the tryptophan-niacin metabolism in liver. It was concluded from these results that the conversion of tryptophan to niacin is due to only the liver enzymes and that the role of the kidney would be extremely low.  (+info)

Inhibition of allogeneic T cell proliferation by indoleamine 2,3-dioxygenase-expressing dendritic cells: mediation of suppression by tryptophan metabolites. (2/40)

Indoleamine 2,3-dioxygenase (IDO), an enzyme involved in the catabolism of tryptophan, is expressed in certain cells and tissues, particularly in antigen-presenting cells of lymphoid organs and in the placenta. It was shown that IDO prevents rejection of the fetus during pregnancy, probably by inhibiting alloreactive T cells, and it was suggested that IDO-expression in antigen-presenting cells may control autoreactive immune responses. Degradation of tryptophan, an essential amino acid required for cell proliferation, was reported to be the mechanism of IDO-induced T cell suppression. Because we wanted to study the action of IDO-expressing dendritic cells (DCs) on allogeneic T cells, the human IDO gene was inserted into an adenoviral vector and expressed in DCs. Transgenic DCs decreased the concentration of tryptophan, increased the concentration of kynurenine, the main tryptophan metabolite, and suppressed allogeneic T cell proliferation in vitro. Kynurenine, 3-hydroxykynurenine, and 3-hydroxyanthranilic acid, but no other IDO-induced tryptophan metabolites, suppressed the T cell response, the suppressive effects being additive. T cells, once stopped in their proliferation, could not be restimulated. Inhibition of proliferation was likely due to T cell death because suppressive tryptophan catabolites exerted a cytotoxic action on CD3(+) cells. This action preferentially affected activated T cells and increased gradually with exposure time. In addition to T cells, B and natural killer (NK) cells were also killed, whereas DCs were not affected. Our findings shed light on suppressive mechanisms mediated by DCs and provide an explanation for important biological processes in which IDO activity apparently is increased, such as protection of the fetus from rejection during pregnancy and possibly T cell death in HIV-infected patients.  (+info)

T cell apoptosis by tryptophan catabolism. (3/40)

Indoleamine 2,3-dioxygenase (IDO) is a tryptophan-catabolizing enzyme that, expressed by different cell types, has regulatory effects on T cells resulting from tryptophan depletion in specific local tissue microenvironments. Different mechanisms, however, might contribute to IDO-dependent immune regulation. We show here that tryptophan metabolites in the kynurenine pathway, such as 3-hydroxyanthranilic and quinolinic acids, will induce the selective apoptosis in vitro of murine thymocytes and of Th1 but not Th2 cells. T cell apoptosis was observed at relatively low concentrations of kynurenines, did not require Fas/Fas ligand interactions, and was associated with the activation of caspase-8 and the release of cytochrome c from mitochondria. When administered in vivo, the two kynurenines caused depletion of specific thymocyte subsets in a fashion qualitatively similar to dexamethasone. These data suggest that the selective deletion of T lymphocytes may be a major mechanism whereby tryptophan metabolism affects immunity under physiopathologic conditions.  (+info)

Prokaryotic homologs of the eukaryotic 3-hydroxyanthranilate 3,4-dioxygenase and 2-amino-3-carboxymuconate-6-semialdehyde decarboxylase in the 2-nitrobenzoate degradation pathway of Pseudomonas fluorescens strain KU-7. (4/40)

The 2-nitrobenzoic acid degradation pathway of Pseudomonas fluorescens strain KU-7 proceeds via a novel 3-hydroxyanthranilate intermediate. In this study, we cloned and sequenced a 19-kb DNA locus of strain KU-7 that encompasses the 3-hydroxyanthranilate meta-cleavage pathway genes. The gene cluster, designated nbaEXHJIGFCDR, is organized tightly and in the same direction. The nbaC and nbaD gene products were found to be novel homologs of the eukaryotic 3-hydroxyanthranilate 3,4-dioxygenase and 2-amino-3-carboxymuconate-6-semialdehyde decarboxylase, respectively. The NbaC enzyme carries out the oxidation of 3-hydroxyanthranilate to 2-amino-3-carboxymuconate-6-semialdehyde, while the NbaD enzyme catalyzes the decarboxylation of the latter compound to 2-aminomuconate-6-semialdehyde. The NbaC and NbaD proteins were overexpressed in Escherichia coli and characterized. The substrate specificity of the 23.8-kDa NbaC protein was found to be restricted to 3-hydroxyanthranilate. In E. coli, this enzyme oxidizes 3-hydroxyanthranilate with a specific activity of 8 U/mg of protein. Site-directed mutagenesis experiments revealed the essential role of two conserved histidine residues (His52 and His96) in the NbaC sequence. The NbaC activity is also dependent on the presence of Fe(2+) but is inhibited by other metal ions, such as Zn(2+), Cu(2+), and Cd(2+). The NbaD protein was overproduced as a 38.7-kDa protein, and its specific activity towards 2-amino-3-carboxymuconate-6-semialdehyde was 195 U/mg of protein. Further processing of 2-aminomuconate-6-semialdehyde to pyruvic acid and acetyl coenzyme A was predicted to proceed via the activities of NbaE, NbaF, NbaG, NbaH, NbaI, and NbaJ. The predicted amino acid sequences of these proteins are highly homologous to those of the corresponding proteins involved in the metabolism of 2-aminophenol (e.g., AmnCDEFGH in Pseudomonas sp. strain AP-3). The NbaR-encoding gene is predicted to have a regulatory function of the LysR family type. The function of the product of the small open reading frame, NbaX, like the homologous sequences in the nitrobenzene or 2-aminophenol metabolic pathway, remains elusive.  (+info)

First evidence of catalytic mediation by phenolic compounds in the laccase-induced oxidation of lignin models. (5/40)

The sulfonephthalein indicator, phenol red, exhibits an unusually slow rate of oxidation by laccase from Poliporus pinsitus, in spite of the fact that it is a phenol and therefore a natural substrate for this phenoloxidase enzyme. Nevertheless, after prolonged exposure to laccase (24 h) phenol red is oxidized by more than 90%. We found that phenol red, which can be oxidatively converted into a resonance-stabilized phenoxy radical, performs as a mediator in the laccase-catalyzed oxidation of a nonphenolic substrate (4-methoxybenzyl alcohol) and also of a hindered phenol (2,4,6-tri-tert-butylphenol). In particular, phenol red was found to be at least 10 times more efficient than 3-hydroxyanthranilate (a reported natural phenolic mediator of laccase) in the oxidation of 4-methoxybenzyl alcohol. Other phenols, which do not bear structural analogies to phenol red, underwent rapid degradation and did not perform as laccase mediators. On the other hand, several variously substituted sulfonephthaleins, of different pK2 values, mediated the laccase catalysis, the most efficient being dichlorophenol red, which has the lowest pK2 of the series. The mediating efficiency of phenol red and dichlorophenol red was found to be pH dependent, as was their oxidation Ep value (determined by cyclic voltammetry). We argue that the relative abundance of the phenoxy anion, which is easier to oxidize than the protonated phenol, may be one of the factors determining the efficiency of a phenolic mediator, together with its ability to form relatively stable oxidized intermediates that react with the desired substrate before being depleted in undesired routes.  (+info)

Excretion of anthranilate and 3-hydroxyanthranilate by Saccharomyces cerevisiae: relationship to iron metabolism. (6/40)

Resting suspensions of cells of Saccharomyces cerevisiae grown in iron-rich or iron-deficient conditions were studied by following the fluorescence emission changes (lambda em. 400-460 nm, lambda exc. 300-340 nm) occurring in these suspensions upon addition of glucose and ferric iron. The results show that, in addition to NAD(P)H, metabolites of the aromatic amino acid pathway interfere with the fluorescence measurements, and that they could be involved in ferric iron reduction. Wild-type strains of S. cerevisiae are known to excreted anthranilic acid and 3-hydroxyanthranilic acid in response to glucose. The major fluorescing compound excreted by a chorismate-mutase-deficient mutant strain of S. cerevisiae was identified as anthranilic acid. The excretion of anthranilic and 3-hydroxyanthranilic acids was correlated with the ferric-reducing capacity of the extracellular medium. Excretion during growth was much greater by cells cultured in iron-rich medium than by cells grown in iron-deficient medium. The possibility was examined that a link could exist between the biosynthesis of aromatics and the ferri-reductase activity of the cells, via chorismate synthase and its putative diaphorase-associated activity. Two ferri-reductase-deficient mutants excreted much less 3-hydroxyanthranilate than did the parental wild-type strains. However, the ferri-reductase activity of a chorismate-synthase-deficient mutant was comparable to that of the parental strain.  (+info)

Inducible and constitutive kynureninases. Control of the inducible enzyme activity by transamination and inhibition of the constitutive enzyme by 3-hydroxyanthranilate. (7/40)

The inducible kynureninase from Neurospora crassa is inactivated by incubation with L-alanine or L-ornithine. The inactivated enzyme is resolved to the apoenzyme by dialysis. Reactivation of the apoenzyme is achieved by incubation with pyridoxamine 5'-phosphate plus pyruvate, as well as with pyridoxal 5'-phosphate. The kynurenine hydrolysis proceeds linearly in the presence of added pyridoxal 5'-phosphate, or pyridoxamine 5'-phosphate plus pyruvate. These findings indicate that the fungal inducible kynureninase can act as an amino-transferase to control the enzyme activity, and that the control mechanism is similar to that reported for the bacterial kynureninase (Moriguchi, M. & Soda, K. (1973) Biochemistry 12, 2974-2980). The ratio of kynureninase activity to aminotransferase activity was determined with bacterial and fungal enzymes. All the inducible kynureninases from various fungal species examined are also controlled by the transamination. In contrast, the pig liver kynureninase and the fungal constitutive enzymes are little or not at all affected by preincubation with amino acids. Thus, the present regulatory mechanism does not operate in these constitutive-type enzymes. The rate of hydrolysis of L-3-hydroxykynurenine by the pig liver enzyme decreases with increase in the incubation time; the enzyme is inhibited by 3-hydroxyanthranilate produced from L-3-hydroxykynurenine. The inhibition is found in all the constitutive-type enzymes, suggesting that 3-hydroxyanthranilate plays a regulatory role in NAD biosynthesis from tryptophan.  (+info)

Characterization of a pseudomonad 2-nitrobenzoate nitroreductase and its catabolic pathway-associated 2-hydroxylaminobenzoate mutase and a chemoreceptor involved in 2-nitrobenzoate chemotaxis. (8/40)

Pseudomonas fluorescens strain KU-7 is a prototype microorganism that metabolizes 2-nitrobenzoate (2-NBA) via the formation of 3-hydroxyanthranilate (3-HAA), a known antioxidant and reductant. The initial two steps leading to the sequential formation of 2-hydroxy/aminobenzoate and 3-HAA are catalyzed by a NADPH-dependent 2-NBA nitroreductase (NbaA) and 2-hydroxylaminobenzoate mutase (NbaB), respectively. The 216-amino-acid protein NbaA is 78% identical to a plasmid-encoded hypothetical conserved protein of Polaromonas strain JS666; structurally, it belongs to the homodimeric NADH:flavin mononucleotide (FMN) oxidoreductase-like fold family. Structural modeling of complexes with the flavin, coenzyme, and substrate suggested specific residues contributing to the NbaA catalytic activity, assuming a ping-pong reaction mechanism. Mutational analysis supports the roles of Asn40, Asp76, and Glu113, which are predicted to form the binding site for a divalent metal ion implicated in FMN binding, and a role in NADPH binding for the 10-residue insertion in the beta5-alpha2 loop. The 181-amino-acid sequence of NbaB is 35% identical to the 4-hydroxylaminobenzoate lyases (PnbBs) of various 4-nitrobenzoate-assimilating bacteria, e.g., Pseudomonas putida strain TW3. Coexpression of nbaB with nbaA in Escherichia coli produced a small amount of 3-HAA from 2-NBA, supporting the functionality of the nbaB gene. We also showed by gene knockout and chemotaxis assays that nbaY, a chemoreceptor NahY homolog located downstream of the nbaA gene, is responsible for strain KU-7 being attracted to 2-NBA. NbaY is the first chemoreceptor in nitroaromatic metabolism to be identified, and this study completes the gene elucidation of 2-NBA metabolism that is localized within a 24-kb chromosomal locus of strain KU-7.  (+info)

  • Several amino acids (AAs) have been shown to be associated with insulin resistance and increased risk of type 2 diabetes, but no previous studies have investigated the association of AAs with insulin secretion in a longitudinal setting. (diabetesjournals.org)
  • However, most of these studies have been cross-sectional, and none of these studies has investigated the association of amino acids (AAs) with changes in insulin secretion in a longitudinal setting. (diabetesjournals.org)
  • belongs to the class of organic compounds known as alpha amino acids. (hmdb.ca)
  • These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). (hmdb.ca)
  • Various studies revealed that C. gattii could assimilate d -proline ( 2 , 3 , 13 , 31 ) and d -tryptophan ( 2 , 3 , 35 ) whereas C. neoformans , including serotype AD, did not assimilate these amino acids. (asm.org)
  • It is shown here that Cu(II), and to a lesser extent Fe(III), enhance oxidation of free 3OHKyn, 3OHAA and 3OHKyn bound to specific amino acids and lens proteins, with this resulting in increased cross-linking of lens proteins. (figshare.com)
  • A Metabolic Relationship Between the Aromatic Amino Acids" by Joseph F. Nyc, Francis A. Haskins et al. (unl.edu)
  • The evidence presented suggests the possibility of a common precursor to the aromatic amino acids. (unl.edu)
  • 3-Hydroxyanthranilic acid oxygenase (3HAO) is the biosynthetic enzyme for quinolinic acid, an endogenous agonist of the NMDA glutamate receptor subtype and a potent neurotoxin. (jneurosci.org)
  • In order to explore the anatomical basis of possible functional interactions between glutamate and quinolinic acid in the rat striatum, pre- and postembedding immunocytochemical methods were used to localize 3HAO immunoreactivity (-i) and glutamate-i at the electron microscopic level. (jneurosci.org)
  • Since quinolinic acid is known to enter the extracellular compartment readily, these results suggest that astrocytic quinolinic acid may participate in the regulation of glutamatergic neurotransmission in the rat striatum. (jneurosci.org)
  • Increased concentrations of excitotoxin quinolinic acid in cerebrospinal fluid (CSF) are associated with infection with the human immunodeficiency virus (HIV-1) and have been implicated in the pathogenesis of the acquired immune deficiency syndrome (AIDS) dementia complex. (docme.ru)
  • In the present study, inoculation of macaques with D/ l/California, an immunosuppressive serotype 1 type D retrovirus, was associated with acute and chronic increases in CSF and serum quinolinic acid concentrations in macaques that had developed SAIDS, a simian disease analogous to AIDS in humans-particularly macaques with demonstrable opportunistic infections. (docme.ru)
  • quinolinic acid, 15.6fold). (docme.ru)
  • Macaques infected with D/ l/California may provide a primate model for investigation of the mechanisms involved in increases in CSF quinolinic acid in retrovirus and other infectious diseases, including HIV-1. (docme.ru)
  • Severe depression is associated with increased microglial quinolinic acid in subregions of the anterior cingulate gyrus: evidence for an immune-modulated glutamatergic neurotransmission? (edu.au)
  • HAAO catalyzes the synthesis of quinolinic acid (QUIN) from 3-hydroxyanthranilic acid. (bio-rad.com)
  • Understand why preventing a build-up of quinolinic acid (QA) is important. (neurohacker.com)
  • It is isomerized by glutamate-1-semialdehyde 2,1-aminomutase to give aminolevulinic acid in the biosynthesis of porphyrins , including heme and chlorophyll . (rug.nl)
  • In endotoxin-treated mice, the activity of indoleamine-2,3-dioxygenase(IDO), the first enzyme of the kynurenine pathway that synthesizes QUIN, is increased in several extrahepatic tissues, plasma L-kynurenine (L-KYN) is elevated , and QUIN, 3-hydroxykynurenine L-TRP and 5-hydroxyindoleacetic acid (5-HIAA) concentrations are increased in cerebral cortex [5, 61. (docme.ru)
  • 2008), it may be predicted that in some forms of epilepsy, over activation of microglial branch with respect to the astrocytic branch of the KP leads to accumulation of QUIN and 3-HK in the CNS. (ukessays.com)
  • It has been proposed that adjunctive treatment with KMO inhibitor along with anti-convulsants can improve the treatment outcome, as inhibition of KMO increase the KYNA production and decrease the 3-HK and QUIN production in the CNS (Campbell et al. (ukessays.com)
  • One molecule, 3-hydroxyanthranilic acid , was orders of magnitude better than the others, and was selected for follow-up in the lab. (thefreedictionary.com)
  • Thus, two equivalents of 3-phosphoglycerate are produced for each molecule of CO 2 that is fixed. (wikipedia.org)
  • In the light-independent reactions (also known as the Calvin cycle), two 3-phosphoglycerate molecules are synthesized, one of which continues through the Calvin cycle to be regenerated to RuBP and the other is reduced to form one molecule of glyceraldehyde 3-phosphate (G3P). (wikipedia.org)
  • Moderate decay due conversion to glutamic acid in improperly stored serum/plasma samples, leading to a marked increase in the Glu/Gln ratio. (uib.no)
  • Moderate decay due conversion to aspartic acid in improperly stored serum/plasma samples, leading to an increase in the Asp/Asn ratio. (uib.no)
  • Perkins and Stone, 1982) discovered that KYNA is a broad spectrum antagonists of glutamate receptor which can inhibit three types of ionotropic receptors- N -methyl-D-aspartate (NMDA), kainate and a-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors. (ukessays.com)
  • Here we test for the chemotaxis of this strain towards six chloro-nitroaromatic compounds (CNACs), namely 2-chloro-4-nitrophenol (2C4NP), 2-chloro-3-nitrophenol (2C3NP), 4-chloro-2-nitrophenol (4C2NP), 2-chloro-4-nitrobenzoate (2C4NB), 4-chloro-2-nitrobenzoate (4C2NB) and 5-chloro-2-nitrobenzoate (5C2NB), and examine its relationship to the degradation of such compounds. (biomedcentral.com)
  • The latter may promote the oxidation of free, or protein-bound, o -aminophenols, such as the UV filter compounds 3-hydroxykynurenine (3OHKyn) and 3-hydroxyanthranilic acid (3OHAA). (figshare.com)
  • In its HO2 form, superoxide can also initiate lipid peroxidation of polyunsaturated fatty acids. (hmdb.ca)
  • EPA is an omega-3 fatty acid whose biological effects include the modulation of inflammatory response. (hindawi.com)
  • By competing with omega-6 fatty acids, EPA is degraded by cellular lipoxygenase and cyclooxygenase. (hindawi.com)
  • Lysoplasmalogenase is specific for the sn- 2-deacylated (lyso) form of plasmalogen and catalyses hydrolytic cleavage of the vinyl ether bond, releasing a fatty aldehyde and sn- glycero-3-phosphocholine or sn- glycero-3-phosphoethanolamine. (qmul.ac.uk)
  • In this article we review evidence supporting opposing roles for IDO-dependent immune regulation-including the generation of regulatory T (Treg) 3 cells ( 4 , 5 )-and the IL-23/Th17 axis in controlling inflammation to specific fungi. (jimmunol.org)
  • In addition to the Th1/Th2 balance, it has recently been shown that the occurrence of long-lasting antifungal protection is dependent on the presence of CD4 + CD25 + regulatory T cells (Treg) 3 that, by negatively regulating anticandidal Th1 reactivity, limit exaggerated inflammatory responses ( 2 ). (jimmunol.org)
  • 3 ⇓ - 5 Less well characterized and of emerging importance are regulatory checkpoints intrinsic to mature, immunostimulatory DCs in controlling the degree and duration of immune responses. (bloodjournal.org)
  • This protein is involved in step 3 of the subpathway that synthesizes quinolinate from L-kynurenine. (uniprot.org)
  • IFNγ can induce chemokine and cytokine secretion in the tumor microenvironment, including IP-10, an angiostatic protein ( 8 , 13 ), and can inhibit tumor angiogenesis ( 3 , 13 , 14 ). (aacrjournals.org)
  • 1 It acts as an antioxidant whether it is free or albumin bound, 2 unconjugated or conjugated, 3,4 and it inhibits both lipid and protein oxidation. (ahajournals.org)
  • 3-Hydroxyanthranilate 34-dioxygenase is a monomeric cytosolic protein belonging to the family of intramolecular dioxygenases containing nonheme ferrous iron. (bio-rad.com)
  • In this paper, we place an emphasis on the role of tumor-infiltrating myeloid cells in maintaining stromal and vascular quiescence, and we underscore the importance of indoleamine 2,3-dioxygenase activity as a myeloid-driven tumor tolerance mechanism. (hindawi.com)
  • Gas chromatographic determination of urinary indole-3-acetic acid. (nii.ac.jp)
  • 3,4 The causative factors of vascular access stenosis include small diameter of artery and vein, surgical technique, previous venipunctures, hemodynamic stress, and the presence of accessory veins. (ahajournals.org)
  • Glycerate 3-phosphate is also a precursor for serine , which, in turn, can create cysteine and glycine through the homocysteine cycle. (wikipedia.org)
  • Lobocka M, Hennig J, Wild J, Kłopotowski T. Organization and expression of the Escherichia coli K-12 dad operon encoding the smaller subunit of D-amino acid dehydrogenase and the catabolic alanine racemase. (labome.org)
  • CATALYTIC ACTIVITY: L-3-hydroxykynurenine + H(2)O = 3- CC hydroxyanthranilate + L-alanine. (genome.jp)
  • PatientContactRelationship IETF language tag This record is generally less unambiguous evidence for efficacy and safety of folic acid decrease plasma homocysteine concentrations in breast cancer-related lymphoedema. (cbdordersnow.com)
  • Glutamate-i was heavily deposited (3-13-fold higher gold particle density than tissue average) in axon terminals forming asymmetric synapses with spines and, occasionally, dendrites. (jneurosci.org)