Abstract：
:The oxidation of quercetin by horseradish peroxidase/H(2)O(2) was studied in the absence but especially also in the presence of glutathione (GSH). HPLC analysis of the reaction products formed in the absence of GSH revealed formation of at least 20 different products, a result in line with other studies reporting the peroxidase-mediated oxidation of flavonoids. In the presence of GSH, however, these products were no longer observed and formation of two major new products was detected. (1)H NMR identified these two products as 6-glutathionylquercetin and 8-glutathionylquercetin, representing glutathione adducts originating from glutathione conjugation at the A ring instead of at the B ring of quercetin. Glutathione addition at positions 6 and 8 of the A ring can best be explained by taking into consideration a further oxidation of the quercetin semiquinone, initially formed by the HRP-mediated one-electron oxidation, to give the o-quinone, followed by the isomerization of the o-quinone to its p-quinone methide isomer. All together, the results of the present study provide evidence for a reaction chemistry of quercetin semiquinones with horseradish peroxidase/H(2)O(2) and GSH ultimately leading to adduct formation instead of to preferential GSH-mediated chemical reduction to regenerate the parent flavonoid.
journal_name
Arch Biochem Biophysjournal_title
Archives of biochemistry and biophysicsauthors
Awad HM,Boersma MG,Vervoort J,Rietjens IMdoi
10.1006/abbi.2000.1832subject
Has Abstractpub_date
2000-06-15 00:00:00pages
224-33issue
2eissn
0003-9861issn
1096-0384pii
S0003-9861(00)91832-0journal_volume
378pub_type
杂志文章abstract：:Osmolytes are small organic molecules accumulated by organisms under stress conditions to protect macromolecular structure and function. In the present study, we have investigated the effect of several binary osmolyte mixtures on the protein folding/stability and function of RNase-A. For this, we have measured ΔGD(o) ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2015.03.017
更新日期：2015-05-01 00:00:00
abstract：:A preliminary study (J.M. Mata, R. Assad, and B. Peterkofsky (1981) Arch. Biochem. Biophys. 206, 93-104) suggested that chick embryo limb bone microsomes took up and concentrated [14C]ascorbate in the presence of cofactors for prolyl hydroxylase. In the present study, we found that the apparent Km for ascorbate in the...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(87)90104-4
更新日期：1987-04-01 00:00:00
abstract：:Human cytochrome CYP3A4 is the most abundant of all the P450s in human liver and is involved in the metabolism of many environmental toxicants and drugs. Kinetic studies with CYP3A4 have been hampered due to low activity of this enzyme obtained from recombinant gene expression systems or difficulty in reconstituting a...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1995.1278
更新日期：1995-05-10 00:00:00
abstract：:Quercetin is a flavonoid that has roles in both cytoprotection and cytotoxicity. The relation of queretin's cytoprotective and cytotoxic effects are unknown. Quercetin has been shown to induce expression of hypoxia-inducible factor, a protein that is known to regulate transcription of the erythropoietin (EPO) gene, an...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2017.10.013
更新日期：2017-12-15 00:00:00
abstract：:In this study, oxygen consumption and H(2)O(2) release rate by succinate or pyruvate/malate supplemented mitochondria isolated from skeletal muscle of trained and untrained rats were investigated. The overall mitochondrial antioxidant capacity and the effect of preincubation of mitochondria with GDP, an inhibitor of u...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1999.1494
更新日期：1999-12-15 00:00:00
abstract：:We have shown that superoxide (O2.-) is produced during the oxidation of veratryl alcohol by lignin peroxidase (LiP) by the reaction of the veratryl alcohol cation radical with hydrogen peroxide (D. B. Barr, M. M. Shah, and S. D. Aust, 1993, J. Biol. Chem. 268, 241-244). Compound III, an inactive form of peroxidases c...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1994.1251
更新日期：1994-06-01 00:00:00
abstract：:The neprilysin gene is composed of three distinct 5' noncoding exons which can be joined to the first coding exon to generate multiple mRNA species, all encoding the same protein. Genomic fragments containing upstream sequences of each of these three noncoding exons from the rat neprilysin gene were subcloned in the p...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1998.0855
更新日期：1998-10-01 00:00:00
abstract：:Saccharopine dehydrogenase catalyzes the NAD-dependent oxidative deamination of saccharopine to l-lysine and α-ketoglutarate. Lysine 99 is within hydrogen-bond distance to the α-carboxylate of the lysine substrate and D319 is in the vicinity of the carboxamide side chain of NADH. Both are conserved and may be importan...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2011.07.013
更新日期：2011-10-01 00:00:00
abstract：:The aim of this study was to investigate the effect of insulin resistance on glycogen concentration and glycogen synthase activity in the red and white gastrocnemius muscles and to determine whether the inverse relationship existing between glycogen concentration and enzyme activity is maintained in insulin resistant ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2007.04.012
更新日期：2007-08-01 00:00:00
abstract：:Bovine kidney mitochondrial extracts contain an inactive protamine kinase and an inactive casein kinase. The protamine kinase was activated by chromatography on poly(L-lysine)-agarose. Two forms of this soluble mitochondrial protamine kinase were separated by chromatography on protamine-agarose. Both forms were purifi...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(88)90408-0
更新日期：1988-05-01 00:00:00
abstract：:The glutamine synthetase (GS) gene is expressed at high levels in several cell types, including astrocytes, pericentral hepatocytes, and adipocytes. During hormone-mediated adipocyte differentiation of 3T3-L1 cells, GS gene expression increases several hundred fold. We previously reported that elements in the distal 5...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2001.2666
更新日期：2002-01-15 00:00:00
abstract：:The three-dimensional conformation of a protein provides a wealth of biochemical information and with the advent of cloning techniques that allow the preparation of proteins almost at will, a renewed interest has arisen in the crystallographic determination of protein structures. As in any research technique, however,...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(91)90122-y
更新日期：1991-11-15 00:00:00
abstract：:Although life as we know it evolved in an aqueous medium, the properties of water are not completely understood. In this review, we focus on the role of water in guiding protein folding and stability. Specifically, we discuss the mechanisms of protein folding in an aqueous environment, the effects of water on the fold...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2007.07.007
更新日期：2008-01-01 00:00:00
abstract：:Membrane dielectric as a primary basis for effects of ethanol was examined in synaptic plasma membranes (SPM) of genetically selected ethanol-sensitive long-sleep (LS) and ethanol-resistant short-sleep (SS) mice. Multifrequency phase and modulation of fluorometry of diphenylhexatriene (DPH) was used to resolve structu...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1994.1126
更新日期：1994-03-01 00:00:00
abstract：:The primary site of action for the novel antibiotic, bicyclomycin, in Escherichia coli has been identified to be the rho transcription termination factor. The inhibition of rho poly(C)-stimulated hydrolysis of ATP by bicyclomycin has been found to proceed by a non-competitive, reversible pathway with respect to ATP (K...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1995.0066
更新日期：1995-11-10 00:00:00
abstract：:The oxidation of 6-hydroxy-2,2,5,7,8-pentamethylchroman, Trolox C, and alpha-tocopherol by horseradish peroxidase was examined by stopped-flow and ESR experiments. The catalytic intermediate of horseradish peroxidase during the oxidation of vitamin E analogues and vitamin E was invariably Compound II, and rate constan...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(92)90280-a
更新日期：1992-12-01 00:00:00
abstract：:Properly regulated cyclin proteolysis is critical for normal cell cycle progression. A nine-amino acid peptide motif called the destruction box (D box) is present at the N terminus of the yeast mitotic cyclins. This short sequence is required for cyclin ubiquitination and subsequent proteolysis. The anaphase-promoting...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/s0003-9861(02)00467-8
更新日期：2002-11-15 00:00:00
abstract：:The electron transfer reactions from FeII(CN)6(4-) and W(IV)(CN)8(4-) to the cupric ions in human copper, zinc superoxide dismutase were followed by the micro-stopped-flow method. The kinetic rate data clearly indicate that FeII(CN)6(4-) or W(IV)(CN)8(4-) first forms an adduct with the enzyme through the interaction w...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2000.2055
更新日期：2000-11-15 00:00:00
abstract：:The objective of this study was to investigate the antiproliferative activity and apoptosis-inducing mechanism of Concanavalin A (ConA) on human melanoma A375 cells. We firstly simulated the three-dimensional structure of ConA. Subsequently, we found that ConA possessed remarkable antiproliferative effect on A375 cell...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2008.12.003
更新日期：2009-02-01 00:00:00
abstract：:Maintenance of genome integrity is essential for the proper function of all cells and organisms. In response to both endogenous and exogenous DNA damaging agents, mammalian cells have evolved a delicate system to sense DNA damage, stop cell cycle progression, modulate cell metabolism, repair damaged DNA, and induce pr...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
doi：10.1016/j.abb.2016.02.018
更新日期：2016-03-15 00:00:00
abstract：:The superoxide dismutase from Mycobacterium tuberculosis is the only Cu-containing superoxide dismutase that lacks zinc in the active site. To explore the structural properties of this unusual enzyme, we have investigated its stability by differential scanning calorimetry. We have found that the holo-enzyme is signifi...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2009.04.005
更新日期：2009-06-15 00:00:00
abstract：:Mutagenic substitution of the invariant D42 and D169 residues in phosphoribulokinase (PRK) with amino acids that contain neutral side chains (e.g., alanine or asparagine) results in large decreases in catalytic efficiency (10(5)- and 10(4)-fold for replacement of D42 and D169, respectively). To further evaluate the im...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/s0003-9861(02)00367-3
更新日期：2002-09-15 00:00:00
abstract：:The effects of racemic (+/-) and (+)- and (-)-stereoisomers of isoflurane on depolarization-induced (45)Ca(2+) fluxes mediated by voltage-dependent Ca(2+) channels were investigated in transverse tubule membrane vesicles from rabbit skeletal muscle. In the concentration range 0.5 to 2 mM, (+/-)-isoflurane inhibited (4...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2001.2726
更新日期：2002-02-15 00:00:00
abstract：:Transport of the antifolate cancer drug methotrexate was studied in vesicles isolated from the basolateral membrane of rat liver. Transport of methotrexate by basolateral membrane vesicles (BLMVs) was mostly via uptake into an osmotically active intravesicular space, with some binding (approximately 9%), as shown by i...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(92)90102-3
更新日期：1992-10-01 00:00:00
abstract：:Phenylalanine ammonia-lyase (PAL) catalyzes the beta-elimination of ammonia from L-phenylalanine to trans-cinnamic acid. A study of inhibition of PAL by phenol, ortho-cresol, and meta-cresol gave mixed inhibition; para-cresol is not an inhibitor. The calculated values of K(i) and alphaK(i) are phenol, K(i)=2.1+/-0.5 m...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/s0003-9861(03)00007-9
更新日期：2003-04-15 00:00:00
abstract：:Plumbagin (PLB), a natural naphthoquinone from the traditional folk medicines Plumbago zeylanica, Dionaea muscipula, or Nepenthes gracilis, has been documented possessing a wide variety of pharmacological activities. Although PLB demonstrates anticancer activity in multiple types of malignant cells, the cellular targe...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2017.02.007
更新日期：2017-04-01 00:00:00
abstract：:Some compounds are known to induce solute-nonselective permeability of the inner mitochondrial membrane (IMM) in Ca2+-loaded mitochondria. Existing data suggest that this process, following the opening of a mitochondrial permeability transition pore, is preceded by different solute-selective permeable states of IMM. A...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1998.0738
更新日期：1998-08-01 00:00:00
abstract：:The clinical disorder of recessive congenital methemoglobinemia (RCM, OMIN 250800) is associated with mutations in NADH:cytochrome b5 reductase (cb5r) and manifests as cyanosis from birth. Screening a cyanotic infant indicated elevated methemoglobin levels and decreased cb5r activity suggesting RCM. Sequencing the DIA...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2005.12.015
更新日期：2006-03-01 00:00:00
abstract：:Pasteurella multocida is a pathogen of veterinary and medical importance. Here, we report the 1.85Å resolution crystal structure of the class C acid phosphatase from this organism (denoted rPmCCAP). The structure shows that rPmCCAP exhibits the same haloacid dehalogenase fold and dimeric assembly as the class C enzyme...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2011.02.021
更新日期：2011-05-01 00:00:00
abstract：:The Ah receptor binds 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related aryl hydrocarbons and mediates their biochemical and toxic effects by modifying gene expression. In order to interact with DNA, the TCDD.receptor complex must undergo a poorly understood transformation to a form which is distinguishable by it...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(91)90177-k
更新日期：1991-07-01 00:00:00
