(1) The quinolinate synthetase B protein exists in all nadA and nadC mutants examined.
(2) The presence of cAMP + cAMP receptor protein was essential for the complete derepression of nadA while no effect was evident upon nadB.
(3) She alleged that Epstein went on to make her have sex with Nada Marcinkova, another female Epstein associate .
(4) The structure of the adducts is in conformity with the generation and reactions of dehydro NADA quinone methide (or its radical).
(5) Accordingly, desaturase enzyme preparation contained both o-diphenoloxidase activity and NADA quinone:NADA quinone methide isomerase activity.
(6) Resolution of the NADA desaturase system on Benzamidine Sepharose and Sephacryl S-200 columns yielded the above-mentioned quinone isomerase and NADA quinone methide:dehydro NADA isomerase.
(7) The present paper reports on the mechanism by which dehydro-NADA is oxidatively activated to form reactive intermediate(s) as revealed by pulse radiolysis, electron spin resonance spectroscopy, high performance liquid chromatography, and ultraviolet-visible spectroscopic analysis.
(8) Exogenously added NADA quinone was readily converted by these enzyme preparations to N-acetylnorepinephrine and dehydro NADA.
(9) High-copy-number vectors, carrying either gene nadA, nadB or nadA + nadB, increased quinolinate production 1.5-fold, 2.0-fold and 15-fold respectively.
(10) After ecdysis NADA became the major hemolymph catecholamine in all species as DA decreased rapidly.
(11) The NADA desaturase system which converts NADA to 1,2-dehydro-NADA, surprisingly, does not resemble dehydrogenases such as succinate dehydrogenase.
(12) NADA-sulphate was quantified by an HPLC-ECD method while the decrease in 4-MU was monitored continuously by a fluorimetric procedure.
(13) These studies indicate that NADA quinone is an intermediate during the side chain hydroxylation of NADA by Manduca cuticular enzyme(s).
(14) The remaining nicotinamide mononucleotide accumulates extracellularly and will support the growth of nadA pncB mutants which cannot utilize the nicotinamide resulting from the major pathway of NAD degradation.
(15) In addition, the sulfate conjugate formed, namely N-acetyldopamine-sulfate (NADA-sulfate) was quantified directly by high-pressure liquid chromatography cum electrochemical detection (HPLC-ECD).
(16) Kinetic studies with NADA showed two pH optima of 6.7 and 8.6 for the overall sulphate conjugation and the PST reaction while the PAPS generation occurred maximally at pH 8.0.
(17) Reconstitution of NADA side chain desaturase activity was achieved by mixing the last enzyme fraction with NADA quinone isomerase, obtained from the hemolymph of the same organism, and mushroom tyrosinase.
(18) Evidence for the formation of an unstable intermediate in the synthesis of quinolinate from aspartate and dihydroxyacetone phosphate by Escherichia coli was obtained using toluenized cells of nadA and nadB mutants of this organism and partially purified A and B proteins in dialysis and membrane cone experiments.
(19) Media coverage was, not surprisingly, sparse – one interview for Melody Maker is vague to the point of rendering itself totally “nada”, while an Island press release is something of a bad joke.
(20) Confirmation of the operon arrangement for nadA and pnuC was obtained through the sequence analysis of a 2.4-kilobase DNA fragment which complemented both NadA and PnuC mutant phenotypes.
Nads
Definition:
Example Sentences:
(1) One hour after direct mechanical cardiomassage (DMCM) a moderately pronounced edema of the intercellular spaces in the basal compartment of the seminiferous epithelium, normal content of lactate and succinate dehydrogenases, and a certain decrease in the activity of glucose-6-phosphate dehydrogenases and NAD- and NADP-diaphorases were noted.
(2) Transformed mammalian cells express both the usual NADP-dependent trifunctional methylenetetrahydrofolate dehydrogenase-cyclohydrolase-synthetase as well as the bifunctional NAD-dependent methylenetetrahydrofolate dehydrogenase-cyclohydrolase.
(3) The results are discussed in terms of a two-site model in which separate, but interacting, regions exist on the enzyme to accommodate the adenosine and nicotinamide moieties of NAD, and a single-site model in which the adenosine part of the molecule is bound preferentially and this interacts with the nicotinamide fraction.
(4) The NAD-dependent enzymes (except alpha-GPDH) showed a stronger reactivity in the proximal tubules, while the NADP-dependent ones were more reactive in the thick limb of Henle's loop and distal convoluted tubules.
(5) In contrast, AMP and adenosine did not alter NAD glycohydrolase activity or affect subunit structure.
(6) With cortisol and cortisol-21-aldehyde, product inhibition patterns showed only slope effects with steroid product and NAD+, suggesting a "random" mechanism.
(7) Kinetic studies of glutamate dehydrogenase were made with wide concentration ranges of the coenzymes NAD(+) and NADP(+) and the substrates glutamate and norvaline.
(8) Both substances decreased the concentrations of NAD(+) in the islet cells to about 10% of the control values within 2h after injection.
(9) We investigated the denaturation of tetrameric 20 beta-hydroxysteroid dehydrogenase (20R)-17 beta,20 beta,21-trihydroxysteroid:NAD+ oxidoreductase, EC 1.1.1.53) to find out whether intermediate states are formed during the process.
(10) On subfractionation of this crude mitochondrial fraction with continuous sucrose density gradients, most of the activity of the three enzymes was found at a higher density than NAD+-isocitrate dehydrogenase and at about the same density as glutamate dehydrogenase, confirming earlier reported data for acetyl-CoA synthase.
(11) The effect of dicoumarol on glucuronidation of 3-OH-benzo(a)pyrene (BP) appears to be due to inhibition of UDPglucuronosyltransferase (UDPGT) and not to an inhibited DT-diaphorase (NAD(P)H:quinone oxidoreductase); to date the only enzyme known to be inhibited by dicoumarol.
(12) The increase in concentration of organic cosolvents results in a 2-2.5-fold increase of the maximal reaction rate and a decrease of Michaelis constant for formate of NAD(+)-dependent formate dehydrogenase from methylotrophic bacteria Pseudomonas sp.
(13) Furthermore, NADP was over 1000-fold more potent than NAD in inhibiting the enzyme competitively with respect to NADH.
(14) The possible participation of a Ca(2+)-induced activation of NAD-isocitrate dehydrogenase in this process was investigated.
(15) A 4.1-kb EcoRI fragment which includes the gene (gldA) encoding a glycerol dehydrogenase (G1DH; EC 1.1.1.6; glycerol:NAD oxidoreductase) from Bacillus stearothermophilus var.
(16) It is supposed that the stimulating effect of lactate with NAD+ on the mitochondria respiration is not so much a result of the membrane-damaged action as a result of oxidation of lactate dehydrogenase reaction products: phosphorylative oxidation of pyruvate and nonconjugated oxidation of NADH.
(17) In the presence of glycolate (glyoxylate), and NADH and NAD alone or together in physiological proportions, the rate of serine-to-glycerate conversion was enhanced and sustained by the addition of malate.
(18) Virazole 5'-phosphate was subsequently found to be a potent competitive inhibitor of inosine 5'-phosphate dehydrogenase (IMP:NAD(+) oxidoreductase, EC 1.2.1.14) isolated from Escherichia coli (K(m) = 1.8 x 10(-5) M) with a K(i) of 2.7 x 10(-7) M. Guanosine 5'-phosphate (GMP) was a competitive inhibitor of this enzyme with a K(i) of 7.7 x 10(-5) M. Virazole 5'-phosphate was similarly active against IMP dehydrogenase isolated from Ehrlich ascites tumor cells, with a K(i) of 2.5 x 10(-7) M. The K(m) for this enzyme was 1.8 x 10(-5) M, and the K(i) for GMP was 2.2 x 10(-4) M. These results suggest that the antiviral activity of Virazole might be due to the inhibition of GMP biosynthesis in the infected cell at the step involving the conversion of IMP to xanthosine 5'-phosphate.
(19) The methods described make possible the preparation of fossil samples for light nad transmission electron microscopy.
(20) The activity of soluble NAD-specific hydrogenase was not detected.