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· Instead a slow cleavage of the disulfide bond occurs when both GSH and cisplatin are present in the solution with Pt(II) stabilizing the reduced form by forming the bidentate species Atox1-Pt(NH 3) 2 34 35 . It is known that intra- and intermolecular disulfide bonds can be broken in the presence of platinum complexes 38 39 40 41 42
Click to chatDisulfide bonds have been widely used to develop reduction-responsive drug-delivery systems (DDS) for cancer therapy. We propose that disulfide bonds might be also used as an oxidation-responsive linkage just like thioether bonds which can be oxidized to hydrophilic sulfoxide or sulphone in the presence of oxidation stimuli.
Click to chat· Disulfide bonds and free thiol groups in both proteins and smaller organic molecules like glutathione can trade places through a disulfide exchange reaction. This process is essentially a combination of two direct displacement ((S_N2)-like) events with sulfur atoms acting as nucleophile electrophile and leaving group.
Click to chat· intrumolecuhr disulfide formation in synthetic peptides can be envis- aged (Scheme 1). In approach A both of the cysteine residues to be paired have the same protecting group which is removed to give the dithiol form of the peptide. Oxidation by molecular oxygen or other appropriate reagents provides the intramolecular disulfide.
Click to chatOxidation of cysteine-containing peptides to different oxidation states of the sulfur atoms to form disulfide bridges sulfenic sulfinic and sulfonic acid or the oxidation of the sulfur atoms of cystine to sulfoxide and/or sulfone were studied by MS in presence of copper ions. These reactions were achieved both chemically (by oxygen or
Click to chat1.4.2.4 Trisulfide Bond Formation . Trisulfide bonds are generated by the addition of a sulfur atom to an already persistent disulfide bond by the following reaction Cys–S–S–Cys H 2 S O → Cys–S–S–S–Cys H 2 O (1.4.1) Such a phenomenon was shown to exist in all subclasses of IgG. 41 Trisulfide bond formation was found to occur in inter- but not in intrachain disulfide
Click to chat· Instead a slow cleavage of the disulfide bond occurs when both GSH and cisplatin are present in the solution with Pt(II) stabilizing the reduced form by forming the bidentate species Atox1-Pt(NH 3) 2 34 35 . It is known that intra- and intermolecular disulfide bonds can be broken in the presence of platinum complexes 38 39 40 41 42
Click to chatCancer cells cope with high oxidative stress levels characterized by a shift toward the oxidized form (GSSG) of glutathione (GSH) in the redox couple GSSG/2GSH. Under these conditions the cytosolic copper chaperone Atox1 which delivers Cu(I) to the secretory pathway gets oxidized i.e. a disulfide bond is formed between the cysteine residues of the Cu(I)-binding CxxC motif.
Click to chat· Copper-catalyzed formation of disulfide-linked dimer of bovine covalent dimerization through oxidation of SH groups was observed. The rate of dimer formation increased with increased concentration of both copper and denaturant. The copper-dependent conversion rate of native protein into the cova- stabilized by two disulfide bonds (Cys66
Click to chatARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS 96 92-99 (1962) Copper-Induced Hydrolysis of the Disulfîde Bond1 IRVING M. KLOTZ AND BENEDICT J. CAMPBELL2 From The Department of Chemistry Northwestern University Evanslon Illinois Received July 19 1961 Hydrolysis of the disulfide bond of a model compound the disodium salt of 2 2 -(2- hydroxy-6-sulfonaphthyl-l-azo)diphenyl disulfide
Click to chat· disulfide bond exchange reaction where Cys106 was exchanged by Cys121 and formed a stable heat-induced intermediate 7 having typical features of molten globule state 8 . As part of this study on the char-acterization of β-Lg unfolded intermedi-ates we report here the characterization of copper-dependent formation of the disulfide-
Click to chat· Oxidation of Human Copper Chaperone Atox1 and Disulfide Bond Cleavage by Cisplatin and Glutathione. Nardella MI(1) Rosato A(1) Belviso BD(2) Caliandro R(2) Natile G(1) Arnesano F(3). Author information (1)Department of Chemistry University of Bari via Orabona 4 70125 Bari Italy.
Click to chat· death suggests the oxidation of the disulfide bonds of thiol groups of membrane proteins both the role of cysteine residues in proteins known in . E. coli. will also be discussed. In addition previous studies which focus on the effect of copper on disulfide bonds will be reviewed and discussed. Lastly previous studies of copper ion
Click to chat· oxidation of disulfide-containing spectator peptides and proteins . A variety of aryl and alkyl disulfides underwent facile oxidation with hydrogen peroxide in the presence of catalytic benzo-1 2-oxaselenolane Se-oxide affording the corresponding thiolsulfinates as the principal products.
Click to chat· If copper forms incorrect disulfide bonds between any free thiol groups this strain might be especially sensitive to the effects of copper in the absence of a disulfide isomerase such as DsbC. A dsbA strain exactly fits these criteria because it lacks DsbA and therefore acquires disulfides more slowly than a wild-type strain ( 2 ).
Click to chat· Oxidation of Human Copper Chaperone Atox1 and Disulfide Bond Cleavage by Cisplatin and Glutathione Maria I. Nardella 1 Antonio Rosato 1 Benny D. Belviso 2 Rocco Caliandro 2 Giovanni Natile 1 and Fabio Arnesano 1 1 Department of Chemistry University of
Click to chatThe kinetics of the oxidation of copper(I) perchlorate with thiuram disulfide (tds) in acetonitrile and its mixtures with benzene or ethyl bromide have been investigated. It has been shown that the rate of the reaction is limited by the inner-sphere transfer of an electron from the copper(I) ion to tds in a complex of the type CuI(tds) . The subsequent dissociation of the anionradical tds
Click to chat· Oxidation of Human Copper Chaperone Atox1 and Disulfide Bond Cleavage by Cisplatin and Glutathione. Nardella MI(1) Rosato A(1) Belviso BD(2) Caliandro R(2) Natile G(1) Arnesano F(3). Author information (1)Department of Chemistry University of Bari via Orabona 4 70125 Bari Italy.
Click to chat· Fig. 3 shows that the copper extraction increases rapidly with iron ion addition in the initial abiotic leaching period. The Cu extraction in 303 K-Non and 318 K-Non was mainly due to the O 2 oxidation effect at an initial pH value of 1.7. The copper extraction in systems set at 318 K is higher than that at 303 K during the initial 18 days.
Click to chat· Under these conditions the cytosolic copper chaperone Atox1 which delivers Cu(I) to the secretory pathway gets oxidized i.e. a disulfide bond is formed between the cysteine residues of the Cu(I)-binding CxxC motif. Switching to the covalently-linked form sulfur atoms are not able to bind the Cu(I) ion and Atox1 cannot play an antioxidant role.
Click to chat· Fig. 3 shows that the copper extraction increases rapidly with iron ion addition in the initial abiotic leaching period. The Cu extraction in 303 K-Non and 318 K-Non was mainly due to the O 2 oxidation effect at an initial pH value of 1.7. The copper extraction in systems set at 318 K is higher than that at 303 K during the initial 18 days.
Click to chatCancer cells cope with high oxidative stress levels characterized by a shift toward the oxidized form (GSSG) of glutathione (GSH) in the redox couple GSSG/2GSH. Under these conditions the cytosolic copper chaperone Atox1 which delivers Cu(I) to the secretory pathway gets oxidized i.e. a disulfide bond is formed between the cysteine residues of the Cu(I)-binding CxxC motif.
Click to chatwith a copper and zinc ion in each subunit functions as an Disulfide Bonds. Disulfide cross-linked SOD1 is not apparent in ventitious air oxidation or disulfide scrambling. To prevent such changes in the disulfide status of SOD1 during tissue grinding cell lysis and electrophoresis 100 mM iodoacetamide (IA) was added
Click to chat· Disulfide bonds have been reported to play a significant role in the structure and function of proteins. Protein stability may decrease when a disulfide bond is removed and addition of a disulfide bond through protein engineering can increase the protein s thermal stability . For this reason due caution has been applied to antibody disulfide reduction that occurs as a results of cell breakage during
Click to chat· Cu(II)-catalyzed oxidative and reductive cleavage of a disulfide bond in a disulfidedipicolinamide L is reported for the first time. Cu(II) gives a complete oxidation up to sulfonates forming a thermally stable 2D complex while Ag(I) oxidizes it up to sulfinate only.
Click to chat· formation of intermolecular disulfide bonds by copper- induced oxidation of sulfhydryl residues. FGF-1 hom- odimers bound with similar apparent affinity as FGF- 1 monomers to immobilized copper ions both eluting at 60 mM imidazole. Both human FGF-1 monomer and dimer forms had a 6-fold higher apparent affinity for
Click to chatA mild and efficient oxidation of various thiols affords the corresponding disulfides using 1 3-dibromo-5 5-dimethylhydantoin (DBDMH) as oxidant under both solution and solvent-free conditions. A. Khazaei M. A. Zolfigol A. Rostami Synthesis 2004 .
Click to chat· Copper a redox active metal is thought to randomly oxidize unpaired cysteines very rapidly so that in the presence of copper it is important to have effective thiol/disulfide isomerases . Because DsbC corrects the misoxidized disulfides it confers copper resistance to bacteria ( Fig. 6D ).
Click to chatThiol oxidation to disulfides is an area of great importance in organic synthesis both for synthetic and dues that form pairs with disulfide bonds.5 In fact some of copper nanoparticles bromine N-bromo-derivatives nitrogen-containing oxidants diethyl azodicarboxylate sul-
Click to chatThe oxidation of cysteine (RSH) has been studied by using O2 ferricytochrome c (Cyt c) and nitro blue tetrazolium (NBT) as electron acceptors. The addition of 200μM CuII to a solution of 2mM cysteine pH 7.4 produces an absorbance with a peak at 260 nm and a shoulder at 300 nm. Generation of a cuprous bis-cysteine complex (RS-CuI-SR) is responsible for this absorbance.
Click to chat· Under these conditions the cytosolic copper chaperone Atox1 which delivers Cu(I) to the secretory pathway gets oxidized i.e. a disulfide bond is formed between the cysteine residues of the Cu(I)-binding CxxC motif.
Click to chat· Thiol-copper(I) and disulfide–dicopper(I) complex O2-reactivity leading to sulfonate–copper(II) complex or the formation of a cross-linked thioether–phenol product with phenol addition. Journal of Inorganic Biochemistry 2007 101 (11-12) .
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