Abstract:
:In addition to its superoxide dismutase (SOD) activity, Cu,Zn-superoxide dismutase (CuZnSOD) catalyzes the reductive decomposition of S-nitroso-L-glutathione (GSNO) in the presence of thiols such as L-glutathione (GSH). The GSNO-reductase activity but not the superoxide dismutase (SOD) activity of CuZnSOD is inhibited by the commonly used polyaminocarboxylate metal ion chelators, EDTA and DTPA. The basis for this selective inhibition is systematically investigated here. Incubation with EDTA or DTPA caused a time-dependent decrease in the 680 nm d-d absorption of Cu(II)ZnSOD but no loss in SOD activity or in the level of metal loading of the enzyme as determined by ICP-MS. The chelators also protected the SOD activity against inhibition by the arginine-specific reagent, phenylglyoxal. Measurements of both the time course of SNO absorption decay at 333 nm and oxymyoglobin scavenging of the NO that is released confirmed that the chelators inhibit CuZnSOD catalysis of GSNO reductive decomposition by GSH. The decreased GSNO-reductase activity is correlated with decreased rates of Cu(II)ZnSOD reduction by GSH in the presence of the chelators as monitored spectrophotometrically at 680 nm. The aggregate data suggest binding of the chelators to CuZnSOD, which was detected by isothermal titration calorimetry (ITC). Dissociation constants of 0.08 +/- 0.02 and 8.3 +/- 0.2 microM were calculated from the ITC thermograms for the binding of a single EDTA and DTPA, respectively, to the CuZnSOD homodimer. No association was detected under the same conditions with the metal-free enzyme (EESOD). Thus, EDTA and DTPA must bind to the solvent-exposed active-site copper of one subunit without removing the metal. This induces a conformational change at the second active site that inhibits the GSNO-reductase but not the SOD activity of the enzyme.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Ye M,English AMdoi
10.1021/bi061077osubject
Has Abstractpub_date
2006-10-24 00:00:00pages
12723-32issue
42eissn
0006-2960issn
1520-4995journal_volume
45pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::The [2Fe-2S] cluster of the Rieske iron-sulfur protein is held between two loops of the protein that are connected by a disulfide bridge. We have replaced the two cysteines that form the disulfide bridge in the Rieske protein of Saccharomyces cerevisiae with tyrosine and leucine, and tyrosine and valine, to evaluate t...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi035344r
更新日期:2003-11-25 00:00:00
abstract::The oxidation of deoxy- and oxyhemerythrin to methemerythrin by Fe(CN)6(3-) has been examined. The first step produces (semi-met)O, a half-oxidized form of hemerythrin which has different spectral and kinetic properties from (semi-met)R which is produced by one-electron reduction of methemerythrin. Further oxidation o...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00559a003
更新日期:1980-09-02 00:00:00
abstract::Elastin binding proteins from plasma membranes of elastin-producing cells were isolated by affinity chromatography on immobilized elastin peptides. Three proteins of 67, 61, and 55 kDa were released from the elastin resin by guanidine/detergent, soluble elastin peptides, synthetic peptide VGVAPG, or galactoside sugars...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00435a014
更新日期:1989-05-02 00:00:00
abstract::The HIV-1 virulence factor Nef interacts with the macrophage Src-family kinase Hck, resulting in constitutive kinase activation that contributes to viral replication and immune escape. Previous chemical library screens identified the diphenylfuranopyrimdine kinase inhibitor DFP-4AB, which selectively inhibits Nef-depe...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.5b00875
更新日期:2015-10-20 00:00:00
abstract::The mitogen-activated protein kinases (MAPKs) are key components of cellular signal transduction pathways, which are down-regulated by the MAPK phosphatases (MKPs). Catalytic activity of the MKPs is controlled both by their ability to recognize selective MAPKs and by allosteric activation upon binding to MAPK substrat...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.7b00827
更新日期:2017-11-21 00:00:00
abstract::When grown under O2-limited conditions, Escherichia coli expresses a cytochrome bd quinol oxidase that has an unusually high affinity for O2. We have studied the reaction of cytochrome bd with CO and O2 by rapid-reaction spectrophotometry. The reduced enzyme forms a photosensitive ferrocytochrome d-CO complex, and fol...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00254a021
更新日期:1994-12-20 00:00:00
abstract::The electron spin echo decay envelope for the blue copper protein, stellacyanin, and for a number of other Cu(II) complexes has been studied. Particular attention was given to the form of the "nuclear modulation" patterns, which show the effects of coupling between the electron spin and the neighboring nuclei. The env...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00662a033
更新日期:1976-08-24 00:00:00
abstract::The aureolic acid antitumor antibiotic mithramycin (MTM) inhibits both cancer growth and bone resorption by cross-linking GC-rich DNA, thus blocking binding of Sp-family transcription factors to gene regulatory elements. Transcription of c-src, a gene implicated in many human cancers and required for osteoclast-depend...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi034091z
更新日期:2003-07-15 00:00:00
abstract::The repair of the endogenous lesion 8-oxo-7,8-dihydrodeoxyguanosine (8-oxodG) was investigated in the nucleotide excision repair mutant xeroderma pigmentosum D (XPD), using human normal or transformed XPD fibroblasts and the Chinese hamster XPD cell line UV5. In vivo repair of 8-oxodG induced by hydrogen peroxide trea...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi992610l
更新日期:2000-08-29 00:00:00
abstract::The sex steroid binding protein (SBP) of human pregnancy serum was purified to homogeneity by the sequential use of ammonium sulfate precipitation, affinity chromatography on 5alpha-dihydrotestosterone-17beta-succinyldiaminoethyl-(1,4-butanediol diglycidyl ether)-agarose, and preparative polyacrylamide gel electrophor...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00601a008
更新日期:1978-04-18 00:00:00
abstract::The binding equilibrium of phospholipase A2 (PLA2) to the substrate interface influences many aspects of the overall kinetics of interfacial catalysis by this enzyme. For example, the interpretation of kinetic data on substrate specificity was difficult when there was a significant kinetic contribution from the interf...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00243a037
更新日期:1991-07-23 00:00:00
abstract::tRNase Z, which exists in almost all cells, is believed to be working primarily for tRNA 3' maturation. In Escherichia coli, however, the tRNase Z gene appears to be dispensable under normal growth conditions, and its physiological role is not clear. Here, to investigate a possibility that E. coli tRNase Z cleaves RNA...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi051972s
更新日期:2006-05-02 00:00:00
abstract::Replication protein A (RPA) is a heterotrimeric protein that is required for DNA replication and most DNA repair pathways. RPA has previously been shown to play a role in recognizing and binding damaged DNA during nucleotide excision repair (NER). RPA has also been suggested to play a role in psoralen DNA interstrand ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi800460d
更新日期:2008-09-23 00:00:00
abstract::Transferrin exhibits heterogeneity in glycosylation characteristic of pathological changes in alcohol abuse and congenital disorders in glycosylation. This study investigated an alternative approach in the detection of carbohydrate-deficient transferrin based on the premise that glycosylation may afford some degree of...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi051749v
更新日期:2005-12-13 00:00:00
abstract::Electron spin resonance (ESR) spectroscopy using spin-labeled ATP was used to study nucleotide binding to and structural transitions within the multidrug resistance P-glycoprotein, P-gp. Spin-labeled ATP (SL-ATP) with the spin label attached to the ribose, was observed to be an excellent substrate analogue for P-gp. S...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0512445
更新日期:2005-10-25 00:00:00
abstract::The resonance Raman spectra of yeast ferri- and ferro-iso-1-cytochrome c dissolved in H2O and D2O are reported. Hydrogen exchange in the protein leads to distinct spectral changes of heme vibrational bands, particularly in the region between 670 and 710 cm-1 and at approximately 443 and approximately 450 cm-1. The lat...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00214a013
更新日期:1993-12-28 00:00:00
abstract::Each regulatory subunit of the cAMP-dependent protein kinase contains two in-tandem cAMP binding sites. Photolabeling of holoenzyme I with 8-azidoadenosine 3',5'-monophosphate (8-N3-cAMP) leads to the covalent modification of two residues, Trp-260 and Tyr-371. In order to correlate photolabeling of these two residues ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00386a035
更新日期:1987-06-16 00:00:00
abstract::The ligand-binding dynamics and the reaction with O(2) of the fully (five-electron) reduced cytochrome caa(3) from the thermohalophilic bacterium Rhodothermus (R.) marinus were investigated. The enzyme is a proton pump which has all the residues of the proton-transfer pathways found in the mitochondrial-like enzymes c...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi010344h
更新日期:2001-09-04 00:00:00
abstract::Proton nuclear magnetic resonance spectra of human hemoglobins in water reveal several exchangeable protons which are indicators of the quaternary structures of both the liganded and unliganded molecules. A comparison of the spectra of normal human adult hemoglobin with those of mutant hemoglobins Chesapeake (FG4alpha...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00682a036
更新日期:1975-06-03 00:00:00
abstract::Protein-protein interactions such as those between small G proteins and their effector proteins control most cell signaling pathways and thereby govern many cellular processes in both normal and disease states. Each small G protein interacts with several effectors, some shared between similar G proteins and others uni...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi701539x
更新日期:2007-12-11 00:00:00
abstract::Tetrachlorohydroquinone dehalogenase catalyzes the replacement of chlorine atoms on tetrachlorohydroquinone and trichlorohydroquinone with hydrogen atoms during the biodegradation of pentachlorophenol by Sphingomonas chlorophenolica. The sequence of the active site region of tetrachlorohydroquinone dehalogenase is ver...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9923813
更新日期:2000-05-09 00:00:00
abstract::Heme propionate-7 in cytochrome c is an ionizable group located in a region of the protein that is inaccessible to bulk solvent. Electrostatic stabilization of this functional group appears to be achieved through interaction of heme propionate-7 with several amino acid residues that occur within hydrogen-bonding dista...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00071a019
更新日期:1993-05-25 00:00:00
abstract::Synaptotagmin I is the calcium sensor in synchronous neurotransmitter release caused by fusion of synaptic vesicles with the presynaptic membrane in neurons. Synaptotagmin I interacts with acidic phospholipids, but also with soluble N-ethylmaleimide-sensitive factor attachment receptors (SNAREs), at various stages in ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi101864k
更新日期:2011-04-05 00:00:00
abstract::The flavoenzyme tryptophan 2-monooxygenase catalyzes the oxidation of tryptophan to indoleacetamide, carbon dioxide, and water. The enzyme is a homologue of l-amino acid oxidase. In the structure of l-amino acid oxidase complexed with aminobenzoate, Tyr372 hydrogen bonds with the carboxylate of the inhibitor in the ac...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi035300i
更新日期:2003-12-02 00:00:00
abstract::Eukaryotic transfer RNA precursors (pre-tRNAs) contain a 5' leader preceding the aminoacyl acceptor stem and a 3' trailer extending beyond this stem. An early step in pre-tRNA maturation is removal of the 5' leader by the endoribonuclease, RNase P. Extensive pairing between leader and trailer sequences has previously ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi000603n
更新日期:2000-08-15 00:00:00
abstract::We have examined the conformational behavior under various unfolding conditions of a predominantly beta-sheet protein, cellular retinoic acid binding protein (CRABP). Urea unfolding-refolding of CRABP is a highly cooperative process that can be approximated by a two-state model. Acid denaturation is also cooperative a...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00167a017
更新日期:1994-01-11 00:00:00
abstract::Conceptually one may envisage that substrate binding sites on the ABC transporter P-gp cycle between high- and low-affinity conformations in response to signals arising from nucleotide hydrolysis to effect active transport. A radioligand binding assay was used to characterize the interaction of [3H]vinblastine with P-...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi011211z
更新日期:2001-12-25 00:00:00
abstract::Base excision repair (BER) plays a vital role in maintaining genomic integrity in mammalian cells. DNA polymerase λ (Pol λ) is believed to play a backup role to DNA polymerase β (Pol β) in base excision repair. Two oxidized abasic lesions that are produced by a variety of DNA-damaging agents, including several antitum...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi301592x
更新日期:2013-02-05 00:00:00
abstract::Photosensitized oxidation reactions damage tissue by catalyzing the formation of oxyradicals and singlet oxygen. beta-Carotene is hypothesized to exert photoprotective effects by quenching singlet oxygen formed by Type II reactions and by scavenging free radicals formed by Type I reactions. beta-Carotene antioxidant m...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9708646
更新日期:1997-10-21 00:00:00
abstract::Telomerase is a ribonucleoprotein that participates in the maintenance of telomere length. Its activity is up-regulated in many tumor types, suggesting that it may be a novel target for chemotherapy. The RNA component of telomerase contains an active site that plays at least two roles&sbd;binding telomere ends and tem...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi970438k
更新日期:1997-09-30 00:00:00