Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Pyruvic Acid”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,423 records · Page 79Linked to original sources
PubMed1975

Glycogenolysis and control of anaphylactic histamine release by cyclic adenosine monophosphate-related agents. II. Modification of histamine release by glycogenolytic metabolites.

D-glucose-6-phosphate (less than or equal to 5 x 10(-3) M), pyruvate, lactate (less than or equal to 1 X 10(-2) M), and dibutyryl cyclic AMP (less than 5 X 10(-3) M) were capable of inhibiting anapylactic histamine release in vitro from chopped guinea pig lung. In lower concentrations, pyruvic acid and lactate, as well as dibutyryl cyclic AMP, enhanced the release. Significant synergism was observed betweenpyruvate (5 X 10(-3) M) and isoproterenol (1 X 10(-8) M) in the inhibition of histamine release. The inhibitory actions of isoproterenol, glucose-6-phosphate, and pyruvate were influenced by calcium ion concentration. However, beta blockade, which diminished the isoproterenol effect, was without efect on pyruvate (1 X 10(-2) M) to the release system. Glucose-6-phosphate and isoproterenol did not have this effect. The results, together with a prevouus study, suggest that glycogenolysis may possess a role in the anaphylactic istamine release in vitro from sensitized lung fragments...

Anaphylaxis↗
PubMed2002

Diabetes causes marked changes in lymphocyte metabolism.

An enhanced susceptibility to infections is well known to occur in a poorly controlled diabetic state. Since glucose and glutamine are essential for lymphocyte function, we investigated whether their metabolism is changed in lymphocytes obtained from mesenteric lymph nodes of alloxan-induced diabetic rats (40 mg/kg body weight). The activities of hexokinase, phosphofructokinase, glucose-6-phosphate dehydrogenase (G6PDH), citrate synthase and phosphate-dependent glutaminase were determined. Decarboxylation of metabolites [U-14C]-, [1-14C]- and [6-14C]-glucose, [1-14C]- and [2-14C]-pyruvic acid, [U-14C]-palmitic acid and [U-14C]-glutamine was evaluated in incubated lymphocytes isolated from mesenteric lymph nodes. The measurements were carried out in cells following three experimental protocols: (1) lymphocytes freshly obtained from control and alloxan-induced diabetic rats, (2) lymphocytes from insulin-treated (2 U/rat per day) diabetic rats and (3) lymphocytes obtained from control and diabetic rats and cultured in the presence of insulin (1 mU/ml) for 6 h. The activities of hexokinase, G6PDH and citrate synthase were decreased by the diabetic state, whereas that of phosphofructokinase was raised. Decarboxylation of [U-14C]- and [6-14C]-glucose, [1-14C]- and [2-14C]-pyruvate and [U-14C]-glutamine were also decreased in lymphocytes from diabetic rats, whereas [U-14C]-palmitic acid decarboxylation was increased. Insulin administration in vivo or added to the culture medium reversed the changes observed in freshly obtained lymphocytes. Alloxan-induced diabetes did change lymphocyte metabolism and this may be an important mechanism leading to impairment of lymphocyte function.

Animals↗
PubMed1962

Galactose metabolism. I. Pathway of carbon in fermentation by Streptococcus faecalis.

Fukuyama T. T. (University of Pennsylvania, Philadelphia) and D. J. O'Kane. Galactose metabolism. I. Pathway of carbon in fermentation by Streptococcus faecalis. J. Bacteriol. 84:793-796. 1962.-The pathway by which galactose-1-C(14) is fermented in Streptococcus faecalis was investigated using dried-cell preparations. Lactic acid, acetic acid, formic acid, ethanol, and carbon dioxide were the end products formed, with lactic acid representing approximately 50% of the sugar fermented. The distribution of radio-activity indicated that the fermentation follows the Embden-Meyerhof route, suggesting that the difference in the formation of the products of glucose and galactose fermentation must be attributed to alternate routes of pyruvic acid metabolism. Differences in pH did not account for the dissimilar fermentation patterns.

Acetates↗
PubMedDate not supplied

[Quantitative determination of lactate, puruvate and methylglyoxa in their mixture].

A method is suggested for nonenzymic spectrophotometric determination of the content of lactic, pyruvic acids and methylglyoxal in their mixture without mutual interference. The determination may be conducted in the biological material after removing protein. 2,4 dinitrophenylhydrazine hydrochloride solution is added to the solution containing the above-mentioned components, then it is centrifuged. The content of lactate and pyruvate is determined in the supernatant fluid, that of methylglyoxal--in the sediment.

Aldehydes↗
PubMed1985

Alternate substrates and inhibitors of bacterial 4-hydroxyphenylpyruvate dioxygenase.

A variety of analogues of (4-hydroxyphenyl)pyruvic acid were synthesized, and the reactions of these compounds with the 4-hydroxyphenylpyruvate dioxygenase from Pseudomonas sp. P.J. 874 were examined. Several of the ring-substituted substrate analogues are reversible inhibitors of the enzyme, the most potent being the competitive inhibitor (2,6-difluoro-4-hydroxyphenyl) pyruvate (Ki = 1.3 microM). Two substrate analogues (2-fluoro-4-hydroxyphenyl)pyruvate and [(4-hydroxyphenyl)thio]pyruvate proved to be alternate substrates for the enzyme. The former compound is converted to (3-fluoro-2,5-dihydroxyphenyl)acetate in an essentially normal catalytic sequence including oxidative decarboxylation, ring hydroxylation, and side-chain migration. The latter compound, however, undergoes oxidative decarboxylation and sulfoxidation to give [(4-hydroxyphenyl)sulfinyl]acetate; ring oxidation is not observed. The implications of these results with regard to the catalytic mechanism of 4-hydroxyphenylpyruvate dioxygenase are discussed.

4-Hydroxyphenylpyruvate Dioxygenase↗
PubMed1992

Metabolism of L-amino acids in a marine bacterium isolated from mackerel intestines in relation to eicosapentaenoic acid biosynthesis.

Metabolism of glucose and L-amino acids in an obligately aerobic marine bacterium isolated from Pacific mackerel intestines was investigated for the mechanism and pathway of eicosapentaenoic acid (EPA) biosynthesis. This bacterium could not uptake glucose but the cell-free extract of this bacterium had the enzymatic activities of L-alanine oxidase (EC 1.4.3.2), L-alanine dehydrogenase (EC 1.4.1.1). L-serine dehydratase (EC 4.2.1.13), and malate dehydrogenase (EC 1.1.1.40), and of seven enzymes involved in the TCA cycle of the usual aerobes. On the other hand, the carbon-13 concentration in cellular fatty acids of the bacterium, especially that in their methyl carbon atoms in contrast to their carbonyl carbons, increased drastically when the bacterium was grown in the presence of 13CH3COONa. These results indicate that: (i) the TCA cycle works in this bacterium, (ii) glucose is not utilized and pyruvic acid is in vivo synthesized from L-alanine, L-serine, and malic acid, and (iii) EPA and other cellular fatty acids are in vivo synthesized from acetyl coenzyme A by the usual de novo synthesis route.

Amino Acids↗
PubMed1976

Eperythrozoon ovis: the difference in carbohydrate metabolism between infected and uninfected sheep erythrocytes.

The glucose utilization lactic and pyruvic acid production and oxygen uptake of normal and Eperythrozoon ovis infected sheep erythrocytes were measured under aerobic conditions. Infected cells showed marded increases in both glucose utilization and acid production as compared with controls. Uninfected erythocyte samples which included a percentage of reticulocytes comparable to that found in E. ovis infection showed no apparent difference in glucose utilization and lactic acid production form the normal control erythrocytes, although considerable increases in the oxygen uptake were recorded.

Anaplasmataceae Infections↗
PubMed2006

Targeted engineering of Azospirillum brasilense SM with indole acetamide pathway for indoleacetic acid over-expression.

Rhizospheric bacterial strains are known to produce indole-3-acetic acid (IAA) through different pathways, and such IAA may be beneficial to plants at low concentrations. IAA biosynthesis by a natural isolate of Azospirillum brasilense SM was studied and observed to be tryptophan-inducible and -dependent in nature. While our work demonstrated the operation of the indole pyruvic acid pathway, the biochemical and molecular evidence for the genes of the indole acetamide (IAM) pathway were lacking in A. brasilense SM. This led us to use the IAM pathway genes as targets for metabolic engineering, with the aim of providing an additional pathway of IAA biosynthesis and improving IAA levels in A. brasilense SM. The introduction of the heterologous IAM pathway, consisting of the iaaM and iaaH genes, not only increased the IAA levels by threefold but also allowed constitutive expression of the same genes along with efficient utilization of IAM as a substrate. Such an engineered strain showed a superior effect on the lateral branching of sorghum roots as well as the dry weight of the plants when compared with the wild-type strain. Such an improved bioinoculant could be demonstrated to enhance root proliferation and biomass productivity of treated plants compared with the parental strain.

Acetamides↗
PubMed1984

Structure and synthesis of histopine, a histidine derivative produced by crown gall tumors.

Histopine, an unusual amino acid derivative of histidine isolated from crown gall tumors of sunflowers (Helianthus annus) inoculated with Agrobacterium tumefaciens strain B6, was previously assigned the gross structure N-(1-carboxyethyl) histidine (2). A diastereomeric mixture containing histopine (2a and 2b) was readily prepared by reductive alkylation of (S)-histidine (1) with pyruvic acid and sodium cyanoborohydride. The individual diastereomers were prepared by reaction of (S)-histidine with (R)- and (S)-2-bromopropionic acid. (R)-N-(1-Carboxyethyl)-(S)-histidine (2a) supports the growth of A. tumefaciens whereas (S)-N-(1-carboxyethyl)-(S)-histidine (2b) is inactive. Therefore, we assign structure 2a to histopine.

Chromatography, High Pressure Liquid↗
PubMed2001

Template-directed C-H insertion: synthesis of the dioxabicyclo[3.2.1]octane core of the zaragozic acids.

[reaction: see text] The preparation of (+/-)-24, a model for the core of the zaragozic acids, is reported. The pivotal reaction in this endeavor is the dirhodium(II)-catalyzed intramolecular C-H bond insertion of 2-diazoacetyl-1,3-dioxane 4, a transformation which generates four of the six stereocenters present in the core structure. A novel method for the diastereoselective synthesis of pyruvic acid acetals was also developed and employed in the preparation of 4 from xylitol derivative 7.

Bridged Bicyclo Compounds, Heterocyclic↗
PubMed2000

Involvement of naphthalene dioxygenase in indole-3-acetic acid biosynthesis by Pseudomonas putida.

Two variants of plant growth-promoting strain Pseudomonas putida BS1380 harboring the naphthalene degradative plasmid pBS2 and the recombinant plasmid pNAU64 that contains the genes encoding for naphthalene dioxygenase were constructed by conjugation. The ability of this strain to produce phytohormone indole-3-acetic acid from different carbon sources was studied. Indole-3-acetic acid synthesis by these transconjugants was 15-30 times as much in contrast to a wild-type strain with glucose as the sole carbon source. No difference was observed in other carbon or nitrogen sources. It is suggested that naphthalene dioxygenase is involved in the conversion of indole-3-pyruvic acid to indole-3-acetic acid.

Cloning, Molecular↗
PubMed2004

Occurrence of pyranoanthocyanins in sparkling wines manufactured with red grape varieties.

The anthocyanin pigments in rosé (Vitis vinifera cv. Garnacha) and blanc de noir (V. vinifera cv. Monastrell) base and sparkling wines were studied by LC-DAD/ESI-MS. Anthocyanins of grape origin and pyranoanthocyanins resulting from C-4/C-5 cycloaddition of the former ones with pyruvic acid, acetaldehyde, 4-vinylphenol, 4-vinylguaiacol, and 4-vinylcatechol were identified in the different wines. Rosé wines presented a higher total pigment content than blanc de noir wines. Pyranoanthocyanins represented 68.9-76.0% of total pigment content in rosé wines and 49.4-60.7% in blanc de noir wines. Malvidin 3-glucoside-pyruvate was the most abundant pigment in both rosé and blanc de noir base wines. Important qualitative and quantitative changes were observed in terms of the anthocyanin and pyranoanthocyanin pigments after the second (bottle) fermentation and 9 months of aging on yeast lees, but not after a further time (3-9 additional months) of aging on lees. Evaluation of the wine color characteristics was consistent with a greater color stability for the rosé sparkling wines that could be associated with the high content, structural diversity, and spectroscopic features of the pyranoanthocyanins present in these wines.

Anthocyanins↗
PubMed2002

Landing responses of Anopheles gambiae elicited by oxocarboxylic acids.

A wind tunnel bioassay and video system were used to observe Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) landing on glass cylinders, heated to human skin temperature (34 degrees C) and treated with aqueous solutions of oxocarboxylic acids. Six of nine compounds tested: 2-oxobutanoic, 2-oxo-3-methylbutanoic, 2-oxopentanoic, 2-oxo-3-methylpentanoic, 2-oxo-4-methylpentanoic and 2-oxohexanoic elicited significant landing responses in comparison to a water control. Landing responses appeared to be restricted to C4-C6, 2-oxocarboxylic acids. A solution of 1 microg/microL of 2-oxopentanoic acid elicited the highest level of response that was temperature dependent: significant numbers of landings occurred only within +/-2 degrees C of human skin temperature. Chemical analysis by linked gas-liquid chromatography/mass spectrometry of methyl-oxime, trimethylsilyl derivatized samples of human sweat extracts revealed the presence of 2-oxopropanoic (pyruvic) acid and three behaviourally active, branched chain acids: 2-oxo-3-methylbutanoic, 2-oxo-3-methylpentanoic and 2-oxo-4-methylpentanoic.

Animals↗
PubMed1996

Purification and properties of aromatic amino acid aminotransferases from Azospirillum brasilense UAP 14 strain.

The purification and characterization of AAT1, one of two aromatic amino acid aminotransferase (EC 2.6.1.57) in Azospirillum brasilense, is described. Purified AAT1 had a subunit mass of 33 kDa and a nondenatured molecular mass of 66 kDa, suggesting a dimeric structure. Other properties include a pI of 5.04, an optimum temperature of 45 degrees C, and optimum pH of 8.5. AAT1 utilized all aromatic amino acids, the L-tryptophan derivatives such as L-5-methyl tryptophan and L-flour-tryptophan, and L-histidine. The apparent Km values for L-tyrosine, L-phenylalanine, and L-tryptophan were 0.19, 0.43, and 1.05 mM, respectively. The enzyme was competive inhibited by indole-3-pyruvic acid with a Ki of 0.17 mM.

Azospirillum brasilense↗
PubMedDate not supplied

[A method of determining pyruvate kinase activity].

A method is suggested for determining the activity of pyruvate kinase (ATP: pyruvate-phosphotransferase). The method is based on evaluation of the amount of ATP formed in the course of phosphoenolpyruvic-to-pyruvic acid transformation in the presence of ADP and magnesium ions. The ATP amount in the reaction medium is determined by paper electrophoresis with subsequent spectrophotometry.

Adenosine Triphosphate↗
PubMed1991

Heat stress and thermal dehydration: lactacidemia and plasma volume regulation.

This investigation was undertaken to study heat stress and dehydration effects on 1) plasma lactic acid (LA) concentration and 2) plasma LA effect on plasma volume conservation during thermal dehydration. Experiments were performed on conscious nonacclimated and heat-acclimated laboratory rats subjected to various levels of heat stress and/or dehydration (37-42 degrees C with and without drinking water). During the exposures, rectal temperature (Tre), plasma LA pyruvic acids, and hematocrit were measured. From these data, excess LA, indicative of anaerobic metabolism, was calculated. In separate experiments, transvascular protein efflux (half time of Evans blue-labeled albumin) was measured before and after plasma LA elevation, either by LA infusion or thermal dehydration. The results show that elevation of plasma LA was associated with a rise in Tre, with accelerated elevation within a Tre range of 41-42 degrees C. LA concentrations were similar for the same Tre in all experimental groups. In nonacclimated rats, this rise was accompanied by a significant rise in excess LA. In acclimated rats, only a minor rise in excess LA was observed. A positive correlation was found between plasma LA elevation and the increase in plasma protein efflux. It is concluded that there is a temperature threshold for the rise in plasma LA. In nonacclimated rats, local hypoxia may contribute to this rise. The data also suggest that, in nonacclimated rats, lactacidemia accelerates plasma protein and fluid loss, leading to circulatory failure during acute thermal dehydration.

Acclimatization↗
PubMedDate not supplied

In vivo metabolism of isomeric naphthalene oxide glutathione conjugates.

We have examined the fate of glutathione conjugates derived from naphthalene metabolism at various dose levels (5-80 mg/kg) in an effort to explore the potential use of urinary mercapturic acids as biomarkers of exposure to naphthalene and as indicators of the activity and stereoselectivity of cytochrome P-450-dependent naphthalene epoxidation. This approach extends previous studies which demonstrated a high degree of stereoselectivity in the formation of (+)-1R,2S-naphthalene oxide from naphthalene in target tissue microsomes (mouse lung), but not in microsomal preparations isolated from nontarget tissues such as mouse liver. To validate the use of mercapturic acids as indicators of epoxide formation in vivo, individual naphthalene oxide glutathione adduct isomers were administered iv to mice, and urinary metabolites were identified and quantified. Mercapturates accounted for 69-75% of the administered dose in the 8-hr urines of animals treated with trans-1-(S)-hydroxy-2-(S)-glutathionyl-1,2-dihydronaphthalene (adduct 1) and 76-84% for trans-1-(R)-hydroxy-2-(R)-glutathionyl-1,2-dihydronaphthalene (adduct 2). Only 39-57% of the dose of trans-1-(R)-glutathionyl-2-(R)-hydroxy-1,2-dihydronaphthalene (adduct 3) administered to mice was excreted as the mercapturic acid derivative; however, two additional metabolites were detected which were not present in the urine of animals treated with adducts 1 or 2. The first metabolite, accounting for 2-4% of the dose of adduct 3, was not identified. The second metabolite, isolated by HPLC and identified by mass spectrometry as (hydroxy-1,2-dihydronaphthalenylthio)pyruvic acid, accounted for 14-25% of the administered dose of adduct 3.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcysteine↗
PubMed1997

A new metabolic link. The acyl carrier protein of lipid synthesis donates lipoic acid to the pyruvate dehydrogenase complex in Escherichia coli and mitochondria.

Lipoic acid is an essential enzyme cofactor that requires covalent attachment to its cognate proteins to confer biological activity. The major lipoylated proteins are highly conserved enzymes of central metabolism, the pyruvate and alpha-ketoglutarate dehydrogenase complexes. The classical lipoate ligase uses ATP to activate the lipoate carboxyl group followed by attachment of the cofactor to a specific subunit of each dehydrogenase complex, and it was assumed that all lipoate attachment proceeded by this mechanism. However, our previous work indicated that Escherichia coli could form lipoylated proteins in the absence of detectable ATP-dependent ligase activity raising the possibility of a class of enzyme that attaches lipoate to the dehydrogenase complexes by a different mechanism. We now report that E. coli and mitochondria contain lipoate transferases that use lipoyl-acyl carrier protein as the lipoate donor. This finding demonstrates a direct link between fatty acid synthesis and lipoate attachment and also provides the first direct demonstration of a role for the enigmatic acyl carrier proteins of mitochondria.

Acyl Carrier Protein↗