Abstract：
:Diquat is a hepatotoxin whose toxicity in vivo and in vitro is mediated by redox cycling and greatly enhanced by pretreatment with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), an inhibitor of glutathione reductase. The mechanism by which redox cycling mediates diquat cytotoxicity is unclear, however. Here, we have attempted to examine the roles of three potential products of redox cycling, namely superoxide anion radical (O2-.), hydrogen peroxide (H2O2), and hydroxyl radical (.OH), in the toxicity of diquat to BCNU-treated isolated hepatocytes. Addition of high concentrations of catalase, but not superoxide dismutase, to the incubations provided some protection against the toxic effect of diquat, but much better protection was observed when catalase was added in combination with the iron chelator desferrioxamine. Addition of desferrioxamine alone also provided considerable protection, whereas the addition of copper ions enhanced diquat cytotoxicity. Taken together, these results indicate that both H2O2 and the transition metals iron and copper could play major roles in the cytotoxicity of diquat. The role of O2-. remains less clear, however, but studies with diethylenetriaminepentaacetic acid indicate that O2-. is unlikely to significantly contribute to the reduction of Fe3+ to Fe2+. The hydroxyl radical or a related species seems the most likely ultimate toxic product of the H2O2/Fe2+ interaction, but hydroxyl radical scavengers afforded only minimal protection.
journal_name
Arch Biochem Biophysjournal_title
Archives of biochemistry and biophysicsauthors
Sandy MS,Moldeus P,Ross D,Smith MTdoi
10.1016/0003-9861(87)90466-8subject
Has Abstractpub_date
1987-11-15 00:00:00pages
29-37issue
1eissn
0003-9861issn
1096-0384pii
0003-9861(87)90466-8journal_volume
259pub_type
杂志文章abstract：:The relative reactivities of lysine residues of tropomyosin complexed with troponin have been measured in order to locate the binding site of troponin on tropomyosin in a complex between the two native proteins. The lysines were labeled with acetic anhydride using a competitive labeling procedure and the relative reac...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(88)90306-2
更新日期：1988-08-01 00:00:00
abstract：:The role of H211 of the yeast F1-ATPase beta-subunit was investigated by site-specific mutagenesis and characterization of the resulting enzymes. Five amino acids (N, D, I, K, and A) were substituted for H211 of the ATP2 gene. The mutated genes were expressed in an atp2::LEU2 host, and only yeast expressing H211N resp...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1996.0056
更新日期：1996-02-01 00:00:00
abstract：:Sphingosine-1-phosphate (SPP) acts as a first messenger in immortalized human airway epithelial cells (CFNPE9o(-)), possibly interacting with an Edg family receptor. Expression of the SPP receptors Edg-1 and Edg-3, as well as a low level of Edg-5/H218, was detected in these cells, in agreement with their ability to sp...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1999.1589
更新日期：2000-03-01 00:00:00
abstract：:The kinetic properties of UDP-glucuronosyltransferase were measured after brief treatment of liver microsomes at alkaline pH, followed by assay with p-nitro-phenol as aglycone, at pH 7.5. Enzyme activity increased in a graded fashion as the pH of pretreatment was increased above 8.0, with apparent maximal activation o...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(90)90585-m
更新日期：1990-03-01 00:00:00
abstract：:Current issues in research on health effects by polyphenols are addressed. As to the cardiovascular system, flow-mediated dilation (FMD), a functional biomarker, can be used as surrogate marker for cardiovascular risk. Acute short-term effects peaking at 2h after ingestion of polyphenol-rich food items are distinguish...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
doi：10.1016/j.abb.2010.04.006
更新日期：2010-09-01 00:00:00
abstract：:DNA of livers or kidneys of rodents contain endogenously modified nucleotides of as yet unknown structure or function. As part of our examination of the origin of endogenous DNA modifications, we examined polar adducts of hamster liver and kidney DNA by 32P-postlabeling analysis (central and upper cuts) and compared t...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1995.1007
更新日期：1995-01-10 00:00:00
abstract：:The parent pyridine nucleotide NAD is the end product of oxidative tryptophan catabolism via the kynurenine pathway. Indoleamine 2, 3-dioxygenase, the rate-limiting enzyme for this pathway, is induced by the proinflammatory cytokine interferon-gamma. The aim of this study was to investigate the effect of interferon-ga...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1999.1381
更新日期：1999-12-01 00:00:00
abstract：:The effects of in vitro addition of halogenated hydrocarbons on the susceptibility of various rat tissues to lipid peroxidation, and of iron overload and dietary vitamin E in the intact rat on subsequent lipid peroxidation in rat tissue slices were examined. The ease and speed of tissue slice preparation allowed testi...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(84)90502-2
更新日期：1984-09-01 00:00:00
abstract：:A quantitative assay has been developed to measure holocarboxylase synthetase activity in cellular extracts. This assay was based on measuring the incorporation of [3H]biotin of high specific activity (4.3 Ci/mmol) into purified rat liver apopyruvate carboxylase. With this assay, holocarboxylase synthetase in 3T3-L1 m...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(83)90026-7
更新日期：1983-08-01 00:00:00
abstract：:The article summarizes the current knowledge on the pathogenesis, clinical aspects and treatment of bone problems in the major inflammatory bowel diseases (Crohn's disease and ulcerative colitis) and celiac disease. It presents the physiological relationship between intestine and bone as well as the alterations determ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章,评审
doi：10.1016/j.abb.2010.06.026
更新日期：2010-11-01 00:00:00
abstract：:The kinetics of the irreversible unfolding of glutathione reductase (NAD[P]H:GSSG oxidoreductase, EC 1.6.4.2.) from cyanobacterium Spirulina maxima was studied at pH 7.0 and room temperature. Denaturation was induced by guanidinium chloride and the changes in enzyme activity, aggregation state, and tertiary structure ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2000.2230
更新日期：2001-03-15 00:00:00
abstract：:Mitochondrial metabolism depends on movement of hydrophilic metabolites through the mitochondrial outer membrane via the voltage-dependent anion channel (VDAC). Here we assessed VDAC permeability of intracellular mitochondria in cultured hepatocytes after plasma membrane permeabilization with 8 microM digitonin. Block...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2008.10.036
更新日期：2009-01-15 00:00:00
abstract：:The secondary structures of staphylococcal nuclease (SNase) have been assigned and semiquantitatively estimated from the deconvoluted Fourier transformed infrared (FTIR) spectrum. The changes in the secondary structures accompanying unfolding and refolding of SNase during reversible thermal denaturation up to 70 degre...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1996.0151
更新日期：1996-04-01 00:00:00
abstract：:Gene expression in the obligate intracellular bacterium Chlamydia trachomatis ranges from nil in the infectious EB form to high in the dividing RB form. Little is known about the mechanisms of gene regulation in chlamydiae and only a few promoter sequences have been characterized. The purpose of our study was to exami...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2000.1854
更新日期：2000-07-01 00:00:00
abstract：:Homogeneous cultures of epithelial, endothelial, and mesangial cells from calf glomeruli were radiolabeled with [35S]sulfate in order to evaluate their capacity for the biosynthesis of the proteoglycan (PG) components present in the glomerular extracellular matrix. Although each cell type was observed to incorporate i...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1995.1371
更新日期：1995-08-01 00:00:00
abstract：:Ferroptosis is a type of iron-dependent, non-apoptotic cell death, which is typically induced by cysteine starvation or by the inhibition of glutathione peroxidase 4 (GPX4) activity with the accompanying elevation in lipid peroxidation product levels. Despite the central role of mitochondria in oxidative metabolism an...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2021.108775
更新日期：2021-01-22 00:00:00
abstract：:Pyruvate dehydrogenase (E1), an alpha(2)beta(2) tetramer, catalyzes the oxidative decarboxylation of pyruvate and reductive acetylation of lipoyl moieties of the dihydrolipoamide acetyltransferase. The roles of betaW135, alphaP188, alphaM181, alphaH15, and alphaR349 of E1 determined by kinetic analysis were reassessed...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2004.06.027
更新日期：2004-09-15 00:00:00
abstract：:2-Isopropenyl-2-methyladamantane (2-PMADA) and 3-isopropenyl-3-methyldiamantane (3-PMDIA) showed potent and selective inhibition of cytochrome P450 (CYP) 2B6-mediated reactions with K(i) values of 5.27 and 2.17 microM, respectively. No effect on activities of other human CYP was found even at concentrations 100-fold h...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/S0003-9861(02)00259-X
更新日期：2002-07-01 00:00:00
abstract：:The effects of nonlamellar-prone lipids, diacylglycerol and phosphatidylethanolamine (PE), on the kinetic association of SecA with model membranes were examined by measuring changes in the intrinsic emission fluorescence with a stopped-flow apparatus. Upon interaction with standard liposomes composed of 50 mol% dioleo...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.2001.2565
更新日期：2001-11-01 00:00:00
abstract：:The absorption spectra of Ni(II) bound to the core histone tetramer, (H3-H4)2, of chicken erythrocytes in 500 mM NaCl + 100 mM phosphate (pH 7.4) were recorded. A charge transfer band was seen at 317 nm, characteristic of a bond between Ni(II) and the sulfur atom of Cys-110 of histone H3. The conditional affinity cons...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1999.1137
更新日期：1999-04-15 00:00:00
abstract：:Glucose oxidase reduces nitroblue tetrazolium, or ferricytochrome c, faster anaerobically than aerobically. This result is inconsistent with the conclusion that GO2 can reduce O2 to O2- which is then responsible for the reduction of NBT and of cytochrome c. Nevertheless, the aerobic reductions are partially inhibitabl...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1006/abbi.1995.1247
更新日期：1995-04-20 00:00:00
abstract：:Partially purified linamarase from Trifolium repens (genotype Lili acac) plants was kinetically characterized. Kinetic evidence was found to support the assumption that this cyanogenic beta-D-glucosidase has a broad substrate spectrum. p-Nitrophenyl-beta-D-xylopyranoside and p-nitrophenyl-alpha-L-arabinopyranoside sub...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(89)90245-2
更新日期：1989-08-01 00:00:00
abstract：:In this study, the binding points of MethB and two structurally-related cationic phenoxazine dyes [meldola blue (MB) and nile blue (NB)] to human butyrylcholinesterase (BChE) were investigated by molecular docking and site directed mutagenesis. The comparative inhibitory effects of MethB, MB and NB on recombinant wild...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2013.01.003
更新日期：2013-04-01 00:00:00
abstract：:The relationships between conformational dynamics, stability and protein function are not obvious. Frataxin (FXN) is an essential protein that forms part of a supercomplex dedicated to the iron-sulfur (Fe-S) cluster assembly within the mitochondrial matrix. In humans, the loss of FXN expression or a decrease in its fu...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2020.108491
更新日期：2020-09-30 00:00:00
abstract：:Type III galactosemia is an inherited disease caused by mutations which affect the activity of UDP-galactose 4'-epimerase (GALE). We evaluated the impact of four disease-associated variants (p.N34S, p.G90E, p.V94M and p.K161N) on the conformational stability and dynamics of GALE. Thermal denaturation studies showed th...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2014.07.030
更新日期：2014-11-15 00:00:00
abstract：:We analyzed the effect of a natural osmolyte, trimethylamine N-oxide (TMAO), on structural properties and conformational stabilities of several proteins under macromolecular crowding conditions by a set of biophysical techniques. We also used the solvent interaction analysis method to look at the peculiarities of the ...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2015.02.021
更新日期：2015-03-15 00:00:00
abstract：:Human leukemic T-lymphocytes undergo extensive and rapid apoptosis in the presence of L1AD3, a small cyclic peptide derivative of cobra cardiotoxin. The first step in this process involves its binding to membranes of susceptible cells. By the use of a biotin "handle" synthetically incorporated at the N-terminus of L1A...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2004.08.010
更新日期：2004-12-01 00:00:00
abstract：:The reduction of prostaglandin H synthase compound II by ascorbic acid in the presence of diethyldithiocarbamate was studied in 0.1 M phosphate buffer (pH 8.0) at 4.0 +/- 0.5 degrees C, by rapid scan spectrometry and transient state kinetics. A saturation effect and nonzero intercept were observed in the plot of pseud...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/0003-9861(90)90445-5
更新日期：1990-09-01 00:00:00
abstract：:Although in vitro models are often used in beta-carotene research, knowledge about the uptake and metabolism of beta-carotene in cell lines is lacking. We measured by HPLC the intracellular levels of beta-carotene and its metabolites in 9 human intestinal and lung cell lines after exposure to 1 microM beta-carotene du...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2005.05.001
更新日期：2005-07-01 00:00:00
abstract：:Carbohydrate Binding Modules (CBMs) targeting cellulose, xylan and mannan have been reported, however, a CBM targeting rhamnogalacturonan I (RG I) has never been identified. We had studied earlier a rhamnogalacturonan lyase (CtRGL) from Clostridium thermocellum that was associated with a family 35 CBM, Rgl-CBM35. In t...
journal_title：Archives of biochemistry and biophysics
pub_type： 杂志文章
doi：10.1016/j.abb.2018.07.023
更新日期：2018-09-15 00:00:00
