Kinetic mechanism of quinone oxidoreductase 2 and its inhibition by the antimalarial quinolines.


:Quinone oxidoreductase 2 (QR2) purified from human red blood cells was recently shown to be a potential target of the quinoline antimalarial compounds [Graves et al., (2002) Mol. Pharmacol. 62, 1364]. QR2 catalyzes the two-electron reduction of menadione via the oxidation of N-alkylated or N-ribosylated nicotinamides. To investigate the mechanism and consequences of inhibition of QR2 by the quinolines further, we have used steady-state and transient-state kinetics to define the mechanism of QR2. Importantly, we have shown that QR2 when isolated from an overproducing strain of E. coli is kinetically equivalent to the enzyme from the native human red blood cell source. We observe ping-pong kinetics consistent with one substrate/inhibitor binding site that shows selectivity for the oxidation state of the FAD cofactor, suggesting that selective inhibition of the liver versus red blood cell forms of malaria may be possible. The reductant N-methyldihydronicotinamide and the inhibitor primaquine bind exclusively to the oxidized enzyme. In contrast, the inhibitors quinacrine and chloroquine bind exclusively to the reduced enzyme. The quinone substrate menadione, on the other hand, binds nonspecifically to both forms of the enzyme. Single-turnover kinetics of the reductive half-reaction are chemically and kinetically competent and confirm the inhibitor selectivity seen in the steady-state experiments. Our studies shed light on the possible in vivo potency of the quinolines and provide a foundation for future studies aimed at creating more potent QR2 inhibitors and at understanding the physiological significance of QR2.






Kwiek JJ,Haystead TA,Rudolph J




Has Abstract


2004-04-20 00:00:00












  • The Structure of the Bimolecular Complex between Amphotericin B and Ergosterol in Membranes Is Stabilized by Face-to-Face van der Waals Interaction with Their Rigid Cyclic Cores.

    abstract::Amphotericin B (AmB) is a polyene macrolide antibiotic isolated from Streptomyces nodosus. The antifungal activity of AmB can be attributed to the formation of an ion-channel assembly in the presence of ergosterol (Erg), in which there are two different AmB-Erg orientations, parallel and antiparallel, as reported prev...


    pub_type: 杂志文章


    authors: Nakagawa Y,Umegawa Y,Matsushita N,Yamamoto T,Tsuchikawa H,Hanashima S,Oishi T,Matsumori N,Murata M

    更新日期:2016-06-21 00:00:00

  • Compartmentation of glucose and fructose 1,6-bisphosphate metabolism in vascular smooth muscle.

    abstract::We examined the metabolism of exogenously added 13C-labeled fructose 1,6-bisphosphate (either labeled at the first and sixth carbons or labeled at the first carbon only) and of [2-13C]glucose in well-oxygenated and well-superfused hog carotid artery segments. Exogenously added fructose 1,6-bisphosphate was utilized by...


    pub_type: 杂志文章


    authors: Hardin CD,Roberts TM

    更新日期:1995-01-31 00:00:00

  • Comparative electron paramagnetic resonance study of radical intermediates in turnip peroxidase isozymes.

    abstract::The occurrence of isozymes in plant peroxidases is poorly understood. Turnip roots contain seven season-dependent isoperoxidases with distinct physicochemical properties. In the work presented here, multifrequency electron paramagnetic resonance spectroscopy has been used to characterize the Compound I intermediate ob...


    pub_type: 杂志文章


    authors: Ivancich A,Mazza G,Desbois A

    更新日期:2001-06-12 00:00:00

  • Resonance Raman characterization of the heme cofactor in cystathionine beta-synthase. Identification of the Fe-S(Cys) vibration in the six-coordinate low-spin heme.

    abstract::Human cystathionine beta-synthase (CBS) is an essential enzyme for the removal of the toxic metabolite homocysteine. Heme and pyridoxal phosphate (PLP) cofactors are necessary to catalyze the condensation of homocysteine and serine to generate cystathionine. While the role for the PLP cofactor is thought to be similar...


    pub_type: 杂志文章


    authors: Green EL,Taoka S,Banerjee R,Loehr TM

    更新日期:2001-01-16 00:00:00

  • The study of pH-dependent stability shows that the TPLH-mediated hydrogen-bonding network is important for the conformation and stability of human gankyrin.

    abstract::Ankyrin repeat (AR) proteins possess a distinctive modular and repetitive architecture, and their global folds are maintained by short-range interactions in terms of the primary sequence. In this work, we extended our previous study on the highly conserved TPLH tetrapeptide and investigated the impact of a solvent-exp...


    pub_type: 杂志文章


    authors: Yuan C,Guo Y,Zhu L,Guo W,Mahajan A,Weghorst CM,Li J

    更新日期:2013-07-16 00:00:00

  • Antisense L/D-oligodeoxynucleotide chimeras: nuclease stability, base-pairing properties, and activity at directing ribonuclease H.

    abstract::Ultraviolet thermal denaturation studies substantiate our earlier hypothesis that substitution of a L-nucleotide residue for a D-nucleotide within a DNA duplex permits a stable structure in which all bases are paired through Watson-Crick hydrogen bonds (Damha, M. J., Giannaris, P. A., Marfey, P., & Reid, L. S. (1991) ...


    pub_type: 杂志文章


    authors: Damha MJ,Giannaris PA,Marfey P

    更新日期:1994-06-28 00:00:00

  • Sarcolipin Promotes Uncoupling of the SERCA Ca2+ Pump by Inducing a Structural Rearrangement in the Energy-Transduction Domain.

    abstract::We have performed microsecond (μs) molecular dynamics simulation (MDS) to identify structural mechanisms for sarcolipin (SLN) uncoupling of Ca2+ transport from ATP hydrolysis for the sarcoplasmic reticulum Ca2+-ATPase (SERCA). SLN regulates muscle metabolism and energy expenditure to provide resistance against diet-in...


    pub_type: 杂志文章


    authors: Autry JM,Thomas DD,Espinoza-Fonseca LM

    更新日期:2016-11-08 00:00:00

  • Presence of divalent cation is not mandatory for the formation of intramolecular purine-motif triplex containing human c-jun protooncogene target.

    abstract::Modulation of endogenous gene function, through sequence-specific recognition of double helical DNA via oligonucleotide-directed triplex formation, is a promising approach. Compared to the formation of pyrimidine motif triplexes, which require relatively low pH, purine motif appears to be the most gifted for their sta...


    pub_type: 杂志文章


    authors: Kaushik S,Kaushik M,Svinarchuk F,Malvy C,Fermandjian S,Kukreti S

    更新日期:2011-05-17 00:00:00

  • High resolution proton nuclear magnetic resonance investigation of the structural and dynamic properties of d(C15A15)-d(T15G15).

    abstract::The high resolution proton nuclear magnetic resonance (NMR) spectra of the synthetic DNA block polymer d(C15A15)-d(T15G15) were studied in order to more completely understand telestability in DNA, and to provide fundamental NMR data on DNA helices and random coils. Spectra were measured in the spectral region from 0 t...


    pub_type: 杂志文章


    authors: Early TA,Kearns DR,Burd JF,Larson JE,Wells RD

    更新日期:1977-02-08 00:00:00

  • Identification of potential regulatory sites of the Na+,K+-ATPase by kinetic analysis.

    abstract::Kinetic models are presented that allow the Na(+),K(+)-ATPase steady-state turnover number to be estimated at given intra- and extracellular concentrations of Na(+), K(+), and ATP. Based on experimental transient kinetic data, the models utilize either three or four steps of the Albers-Post scheme, that is, E(2) --> E...


    pub_type: 杂志文章


    authors: Kong BY,Clarke RJ

    更新日期:2004-03-02 00:00:00

  • Reduction of the [2Fe-2S] cluster accompanies formation of the intermediate 9-mercaptodethiobiotin in Escherichia coli biotin synthase.

    abstract::Biotin synthase catalyzes the conversion of dethiobiotin (DTB) to biotin through the oxidative addition of sulfur between two saturated carbon atoms, generating a thiophane ring fused to the existing ureido ring. Biotin synthase is a member of the radical SAM superfamily, composed of enzymes that reductively cleave S-...


    pub_type: 杂志文章


    authors: Taylor AM,Stoll S,Britt RD,Jarrett JT

    更新日期:2011-09-20 00:00:00

  • Phosphoprotein particles: calcium and inorganic phosphate binding structures.

    abstract::Phosphoprotein particles were isolated in their native state from the physiological fluid of the estuarine clam Rangia cuneata , and the characteristics of the mineral ion-protein complex which constitutes the native particle were investigated by using mineral ion binding and mineral ion exchange techniques. The parti...


    pub_type: 杂志文章


    authors: Marsh ME,Sass RL

    更新日期:1984-03-27 00:00:00

  • Differential release of cellular and scrapie prion proteins from cellular membranes by phosphatidylinositol-specific phospholipase C.

    abstract::The abnormal isoform of the scrapie prion protein PrPSc is both a host-derived protein and a component of the infectious agent causing scrapie. PrPSc and the normal cellular isoform PrPC have different physical properties that apparently arise from a posttranslational event. Both PrP isoforms are covalently modified a...


    pub_type: 杂志文章


    authors: Stahl N,Borchelt DR,Prusiner SB

    更新日期:1990-06-05 00:00:00

  • Interaction of acetylene and cyanide with the resting state of nitrogenase alpha-96-substituted MoFe proteins.

    abstract::The nitrogenase MoFe protein contains the active site metallocluster called FeMo-cofactor [7Fe-9S-Mo-homocitrate] that exhibits an S = 3/2 EPR signal in the resting state. No interaction with FeMo-cofactor is detected when either substrates or inhibitors are incubated with MoFe protein in the resting state. Rather, th...


    pub_type: 杂志文章


    authors: Benton PM,Mayer SM,Shao J,Hoffman BM,Dean DR,Seefeldt LC

    更新日期:2001-11-20 00:00:00

  • Electron-transferring enzymes in the plasma membrane of the Ehrlich ascites tumor cell.

    abstract::The plasma membrane of the Ehrlich ascites tumor cell contains an NADH dehydrogenase. This activity was shown not to be due to contamination by other subcellular membranes. A variety of electron acceptors have been compared as to rate with the following result: ferricyanide greater than cytochrome c greater than cytoc...


    pub_type: 杂志文章


    authors: Kilberg MS,Christensen HN

    更新日期:1979-04-17 00:00:00

  • Interconversion of conformational isomers of light chains in the Mcg immunoglobulins.

    abstract::Previous crystallographic studies in this laboratory demonstrated that immunoglobulin light chains with the same amino acid sequence can have at least two and probably three or more conformations, depending on whether the second member of an interacting pair is a light or heavy chain. If a heavy chain is not available...


    pub_type: 杂志文章


    authors: Firca JR,Ely KR,Kremser P,Westholm FA,Dorrington KJ,Edmundson AB

    更新日期:1978-01-10 00:00:00

  • Three novel oligosaccharides with the sialyl-Lea structure in human milk: isolation by immunoaffinity chromatography.

    abstract::We have determined the structures of three novel oligosaccharides isolated from human milk using the monoclonal antibody MSW 113. These oligosaccharides were purified by affinity chromatography on a column of the immobilized monoclonal antibody and by high-performance liquid chromatography. From the results of 500-MHz...


    pub_type: 杂志文章


    authors: Kitagawa H,Nakada H,Kurosaka A,Hiraiwa N,Numata Y,Fukui S,Funakoshi I,Kawasaki T,Yamashina I,Shimada I

    更新日期:1989-10-31 00:00:00

  • Identification of unfolding domains in large proteins by their unfolding rates.

    abstract::Three unfolding domains in rabbit muscle aldolase destabilized in 3 M urea have been identified from their unfolding rate constants (0.10, 0.036, and 0.0064 min-1). The populations of folded and various, partially unfolded forms were determined by amide hydrogen exchange and mass spectrometry. Results of this study sh...


    pub_type: 杂志文章


    authors: Deng Y,Smith DL

    更新日期:1998-05-05 00:00:00

  • Role of enzyme-peptide substrate backbone hydrogen bonding in determining protein kinase substrate specificities.

    abstract::As part of a search for peptides that have specificity for selected protein kinases, the possibility that adenosine cyclic 3',5'-phosphate dependent protein kinase (A-kinase) recognizes the hydrogen-bonding potential of its peptide substrates was investigated. A-Kinase catalyzes the phosphorylation of five N alpha-met...


    pub_type: 杂志文章


    authors: Thomas NE,Bramson HN,Miller WT,Kaiser ET

    更新日期:1987-07-14 00:00:00

  • Elucidation of the chemical nature of the steady-state intermediates in the mechanism of carboxypeptidase A.

    abstract::Cryospectrokinetic studies of zinc and cobalt carboxypeptidase A disclosed two intermediates in the hydrolysis of both peptides and depsipeptides and furnished all the rate and equilibrium constants for the reaction scheme E + S in equilibrium ES1 in equilibrium ES2---E + P [Auld, D. S., Galdes, A., Geoghegan, K. F., ...


    pub_type: 杂志文章


    authors: Galdes A,Auld DS,Vallee BL

    更新日期:1986-02-11 00:00:00

  • Substrate specificity and excision kinetics of Escherichia coli endonuclease VIII (Nei) for modified bases in DNA damaged by free radicals.

    abstract::Endonuclease VIII (Nei) is one of three enzymes in Escherichia coli that are involved in base-excision repair of oxidative damage to DNA. We investigated the substrate specificity and excision kinetics of this DNA glycosylase for bases in DNA that have been damaged by free radicals. Two different DNA substrates were p...


    pub_type: 杂志文章


    authors: Dizdaroglu M,Burgess SM,Jaruga P,Hazra TK,Rodriguez H,Lloyd RS

    更新日期:2001-10-09 00:00:00

  • Energy-transfer dynamics in three light-harvesting mutants of Rhodobacter sphaeroides: a picosecond spectroscopy study.

    abstract::Picosecond absorption spectroscopy has been used to investigate energy-transfer dynamics within the LH1 and LH2 light-harvesting complexes of three mutants of Rhodobacter sphaeroides. We demonstrate that both complexes are inhomogeneous; each contains a specialized pigment pool which absorbs maximally at a longer wave...


    pub_type: 杂志文章


    authors: Hunter CN,Bergström H,van Grondelle R,Sundström V

    更新日期:1990-04-03 00:00:00

  • Genome-Wide Mapping of Oxidative DNA Damage via Engineering of 8-Oxoguanine DNA Glycosylase.

    abstract::The occurrence of 8-oxo-7,8-dihydroguanine (OG) in the genome, as one of the major DNA oxidative damages, has been implicated in an array of biological processes, ranging from mutagenesis to transcriptional regulation. Genome-wide mapping of oxidative damages could shed light on the underlying cellular mechanism. In t...


    pub_type: 杂志文章


    authors: Fang Y,Zou P

    更新日期:2020-01-14 00:00:00

  • Affinity cleavage at the metal-binding site of phosphoenolpyruvate carboxykinase.

    abstract::Chicken liver phosphoenolpyruvate carboxykinase (PEPCK) was rapidly inactivated by micromolar concentrations of ferrous sulfate in the presence of ascorbate at pH 7.4. Omitting ascorbate or replacing the Fe2+ with Mn2+ or Mg2+ gives no inactivation. Mn2+, Mg2+, or Co2+ at 100-fold molar excess over Fe2+ offered comple...


    pub_type: 杂志文章


    authors: Hlavaty JJ,Nowak T

    更新日期:1997-12-09 00:00:00

  • Selective radiolabeling of cell surface proteins to a high specific activity.

    abstract::A procedure was developed for selective radiolabeling of membrane proteins on cells to higher specific activities than possible with available techniques. Cell surface amino groups were derivatized with 125I-(hydroxyphenyl)propionyl groups via 125I-sulfosuccinimidyl (hydroxyphenyl)propionate (125I-sulfo-SHPP). This re...


    pub_type: 杂志文章


    authors: Thompson JA,Lau AL,Cunningham DD

    更新日期:1987-02-10 00:00:00

  • Accumulation of immunoglobulin messenger ribonucleic acid in immunized mouse spleen.

    abstract::We have measured the concentration of mRNAs coding for immunoglobulins, k and lambda type light chains and gamma 1 type heavy chain, in mouse spleen cells activated by bacterial lipopolysaccharide or sheep red blood cells. These mRNAs were quantitated by hybridization to radioactive DNA complementary to highly purifie...


    pub_type: 杂志文章


    authors: Honjo T,Shimizu A,Tsuda M,Natori S,Katatoka T,Dohmoto C,Mano Y

    更新日期:1977-12-27 00:00:00

  • Probing the Flexibility of the Catalytic Nucleophile in the Lyase Catalytic Pocket of Human DNA Polymerase β with Unnatural Lysine Analogues.

    abstract::DNA polymerase β (Pol β) is a key enzyme in mammalian base excision repair (BER), contributing stepwise 5'-deoxyribose phosphate (dRP) lyase and "gap-filling" DNA polymerase activities. The lyase reaction is believed to occur via a β-elimination reaction following the formation of a Schiff base between the dRP group a...


    pub_type: 杂志文章


    authors: Daskalova SM,Bhattacharya C,Dedkova LM,Hecht SM

    更新日期:2017-01-24 00:00:00

  • Conformation and stability of the constant fragment of the immunoglobulin light chain containing an intramolecular mercury bridge.

    abstract::The constant fragment of the immunoglobulin light chain in which the intramolecular disulfide bond is reduced (reduced CL fragment) assumes a conformation very similar to that of the intact CL fragment and contains two sulfhydryl groups buried in the interior of the molecule [Goto, Y., & Hamaguchi, K. (1979) J. Bioche...


    pub_type: 杂志文章


    authors: Goto Y,Hamaguchi K

    更新日期:1986-05-20 00:00:00

  • Biochemical characterization of the L-plastin-actin interaction shows a resemblance with that of alpha-actinin and allows a distinction to be made between the two actin-binding domains of the molecule.

    abstract::Actin interaction with L-plastin, a plastin/fimbrins isoform of the alpha-actinin family of molecules, is poorly characterized, from the biochemical point of view. Besides, molecular modeling of the T-isoform has recently provided a complete model of interaction with filamentous actin [Volkmann, N., DeRosier, D., Mats...


    pub_type: 杂志文章


    authors: Lebart MC,Hubert F,Boiteau C,Ventéo S,Roustan C,Benyamin Y

    更新日期:2004-03-09 00:00:00

  • Mechanistic aspects of the DNA junction-resolving enzyme T7 endonuclease I.

    abstract::The chemical mechanism of phosphodiester bond hydrolysis catalyzed by a junction-resolving enzyme has been investigated. Endonuclease I of phage T7 is a member of the nuclease superfamily of proteins that include many restriction enzymes, and the structure of the active site is very similar to that of BglI in particul...


    pub_type: 杂志文章


    authors: Liu J,Déclais AC,Lilley DM

    更新日期:2006-03-28 00:00:00