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 of (semi-met)O to methemerythrin usually occurs only indirectly via disproportionation of (semi-met)O to met and deoxy forms within the octameric framework. Oxidation of (semi-met)R by Fe(CN)6(3-) is a direct second-order reaction. (Semi-met)O is reduced rapidly by dithionite to deoxy, whereas that of (semi-met)R is a slow biphasic process. The oxidation of oxyhemerythrin occurs via the deoxy species, little, if any, reactivity being attributable to the oxy form. The oxidation of the azide adduct of (semi-met)R is biphasic, in which in step one N3(-) is removed during the oxidation to methemerythrin, which in the second step recombines with N3(-). Rate parameters for all these processes at pH 8.2 and 6.3 for protein from Phascolopsis gouldii and Themiste zostericola have been obtained. The implications of these findings to hemerythrin chemistry are discussed.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Bradić Z,Harrington PC,Wilkins RG,Yoneda Gdoi
10.1021/bi00559a003subject
Has Abstractpub_date
1980-09-02 00:00:00pages
4149-55issue
18eissn
0006-2960issn
1520-4995journal_volume
19pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::Manganese superoxide dismutase (MnSOD) cycles between the Mn(II) and Mn(III) states during the catalyzed disproportionation of O(2)(*-), a catalysis that is limited at micromolar levels of superoxide by a peroxide-inhibited complex with the metal. We have investigated the role in catalysis and inhibition of the conser...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi011047f
更新日期:2001-10-09 00:00:00
abstract::The reactions of metmyoglobin (metMb) and methemoglobin (metHb), oxidized to their respective oxoferryl free radical species (.Mb-FeIV = O/.Hb-4FeIV = O) by tert-butyl hydroperoxide (t-BuOOH), with nitric oxide (NO.) were studied by a combination of optical, electron spin resonance (ESR), ionspray mass (MS), fluoresce...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00020a014
更新日期:1995-05-23 00:00:00
abstract::Phosphofructokinase from Escherichia coli (EcPFK) is a homotetramer with four active sites and four allosteric sites. Understanding the allosteric activation of EcPFK by MgADP has been complicated by the complex web of possible interactions, including active site homotropic interactions, allosteric site homotropic int...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi048569q
更新日期:2004-11-09 00:00:00
abstract::Acetohydroxy acid synthase (AHAS) is a thiamin diphosphate (ThDP)-dependent enzyme that catalyzes the first common step in the biosynthesis of branched-chain amino acids, condensation of pyruvate with a second 2-ketoacid to form either acetolactate or acetohydroxybutyrate. AHAS isozyme II from Escherichia coli is spec...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi102051h
更新日期:2011-04-19 00:00:00
abstract::The amide hydrogens that are exposed to solvent in the high-resolution X-ray structures of ubiquitin, FK506-binding protein, chymotrypsin inhibitor 2, and rubredoxin span a billion-fold range in hydroxide-catalyzed exchange rates which are predictable by continuum dielectric methods. To facilitate analysis of transien...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi901219x
更新日期:2009-10-06 00:00:00
abstract::We have covalently attached an electron paramagnetic resonance (EPR) spin probe to Cys-670 of the motor domain of ncd (nonclaret disjunctional protein) in order to investigate conformational changes associated with the chemomechanical cycle. Spin-labeling is highly specific and does not affect ncd function as monitore...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9706881
更新日期:1997-08-12 00:00:00
abstract::Intrastrand cross-links represent the majority of modifications in DNA resulting from interaction with the cancer chemotherapeutic drug cis-diamminedichloroplatinum(II) (cis-DDP). These adducts were recently characterized although several discrepancies remained to be resolved. In these studies, [3H]-cis-dichloro(ethyl...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00361a026
更新日期:1986-07-01 00:00:00
abstract::To elucidate the enzymatic excision-repair process operative on cyclobutane-type pyrimidine photodimers in human dermal fibroblasts, we have examined excised dimer-containing material recovered in the trichloroacetic acid soluble fraction from far-ultraviolet-irradiated (254 nm, 40 J m-2) and incubated (24 h) cell cul...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00357a055
更新日期:1986-05-06 00:00:00
abstract::Calculations of the electrostatic potentials were made around yeast elongator phenylalanine, aspartate tRNAs, and yeast initiator methionine tRNA in aqueous solution at physiological ionic strength. The calculations were carried out with a finite difference algorithm for solving the nonlinear Poisson-Boltzmann equatio...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00454a006
更新日期:1990-01-16 00:00:00
abstract::The DNA repair enzyme MutY plays an important role in the prevention of DNA mutations resulting from the presence of the oxidatively damaged lesion 7,8-dihydro-8-oxo-2'-deoxyguanosine (OG) in DNA by the removal of misincorporated adenine residues in OG:A mispairs. MutY also exhibits adenine glycosylase activity toward...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi981594+
更新日期:1998-10-20 00:00:00
abstract::A wide range of two-dimensional 1H NMR experiments have been used to completely assign the 500-MHz 1H NMR spectrum of recombinant Ca2+-saturated bovine calbindin D9k (76 amino acids, Mr = 8500). In solution, calbindin D9k exists as an equilibrium mixture of isoforms with trans (75%) and cis (25%) isomers of the peptid...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00443a043
更新日期:1989-08-22 00:00:00
abstract::Synaptotagmin 1 (syt1) is a synaptic vesicle-anchored membrane protein that acts as the calcium sensor for the synchronous component of neuronal exocytosis. Using site-directed spin labeling, the position and membrane interactions of a fragment of syt1 containing its two C2 domains (syt1C2AB) were assessed in bilayers...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi200049c
更新日期:2011-04-05 00:00:00
abstract::The mature form of subtilisin is an unusual example of a monomeric protein with a high kinetic barrier to folding and unfolding. Using site-directed mutagenesis of subtilisin BPN', we are attempting to determine the physical and energetic nature of the kinetic barrier. The high-affinity calcium-binding site A has been...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00090a012
更新日期:1993-10-05 00:00:00
abstract::p21-activated kinases (PAKs) serve as effector proteins for the GTP-binding proteins Cdc42 and Rac. They are serine/threonine kinases containing the Cdc42/Rac interactive binding (CRIB) motif. The main aim of this study was to define the minimal domain of alphaPAK required for Cdc42/Rac binding. Eight stable PAK fragm...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi980140+
更新日期:1998-05-26 00:00:00
abstract::Metabolism of [2-13C]-, [3-13C]-, and [1,2,3-13C]propionate in perfused rat livers and [2-13C]-acetate in perfused rat hearts has been examined in tissue extracts by 13C NMR. Label from [2-13C]-propionate was preferentially incorporated into the C2 carbon of lactate, alanine, and aspartate in liver tissue while label ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00186a029
更新日期:1994-05-24 00:00:00
abstract::The structural and functional roles of two conserved active site residues, Arg-97 and Arg-132, in chicken muscle adenylate kinase (AK) were evaluated by site-directed mutagenesis in conjunction with one- and two-dimensional proton nuclear magnetic resonance (NMR), kinetics, and guanidine hydrochloride-induced denatura...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00142a022
更新日期:1992-07-14 00:00:00
abstract::A mechanism by which the Klenow fragment of DNA polymerase I monitors the geometry of the base pairs may involve hydrogen bonds between the polymerase and the minor groove of the nascent base pair. The involvement of the 3-position of guanine in the template strand was examined by synthesizing oligodeoxynucleotides co...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi971253g
更新日期:1997-10-28 00:00:00
abstract::We measured the time course of skeletal muscle actin polymerization at different actin concentrations. In 0.1 M KCl with 1 mM Mg2+, log/log plots of the rate of the early, slow phase of polymerization vs. actin concentration were linear with slopes from 1.0 to 1.3. Computer-assisted calculations of similar curves from...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00278a021
更新日期:1983-04-26 00:00:00
abstract::Heme oxygenase (HO) catalyzes the regiospecific cleavage of the porphyrin ring of heme using reducing equivalents and O2 to produce biliverdin, iron, and CO. Because CO has a cytoprotective effect through the p38-MAPK pathway, HO is a potential therapeutic target in cancer. In fact, inhibition of the HO isoform HO-1 r...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi062264p
更新日期:2007-02-20 00:00:00
abstract::We report an unusually high frequency (543 cm(-)(1)) for an Fe-CO stretching mode in the CO complex of Ascaris suum hemoglobin as compared to vertebrate hemoglobins in which the frequency of the Fe-CO mode is much lower. A second Fe-CO stretching mode in Ascaris hemoglobin is observed at 515 cm(-1). We propose that th...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi9922087
更新日期:2000-02-01 00:00:00
abstract::Several experimental approaches have been employed to independently determine rates of dissociation for Escherichia coli RNA polymerase from the T7 bacteriophage A1, A2, A3, and D promoters. Heparin challenge measurements employing abortive initiation turnover rates as an index of promoter occupancy were carried out o...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00552a023
更新日期:1980-05-27 00:00:00
abstract::During a recent investigation of the persistence of substrate ambiguity in contemporary enzymes, we identified three distinct ambiguous sugar kinases embedded within the modern Escherichia coli genome [Miller, B. G., and Raines, R. T. (2004) Biochemistry 43, 6387-6392]. These catalysts are the YajF, YcfX, and NanK pol...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0506268
更新日期:2005-08-16 00:00:00
abstract::The effect of monoclonal anti-(DNA polymerase alpha) immunoglobulin G (IgG) and F(ab) fragments on DNA replication in lysolecithin-permeabilized human cells and on DNA polymerase alpha activity was determined. DNA polymerase alpha activity in vitro was inhibited equally by the same concentrations of monoclonal IgGs an...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00346a061
更新日期:1985-12-03 00:00:00
abstract::Locked nucleic acid (LNA) is a nucleic acid analogue containing one or more LNA nucleotide monomers with a bicyclic furanose unit locked in an RNA mimicking sugar conformation. LNA oligonucleotides display unprecedented hybridization affinity toward complementary single-stranded RNA and complementary single- or double...
journal_title:Biochemistry
pub_type: 杂志文章,评审
doi:10.1021/bi0485732
更新日期:2004-10-26 00:00:00
abstract::Phenylalanine acts as an allosteric activator of the tetrahydropterin-dependent enzyme phenylalanine hydroxylase. Hydrogen/deuterium exchange monitored by mass spectrometry has been used to gain insight into local conformational changes accompanying activation of rat phenylalanine hydroxylase by phenylalanine. Peptide...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi1001294
更新日期:2010-04-20 00:00:00
abstract::We show that eight different serine proteinases--bovine chymotrypsins A and B, porcine pancreatic elastase I, proteinase K, Streptomyces griseus proteinases A and B, and subtilisins BPN' and Carlsberg--interact with turkey ovomucoid third domain at the same Leu18-Glu19 peptide bond, the reactive site of the inhibitor....
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00341a007
更新日期:1985-09-24 00:00:00
abstract::A subgroup of enzymes in the NAD(P)H:FMN reductase family is comprised of flavin reductases from two-component monooxygenase systems. The diverging structural feature in these FMN reductases is a π-helix centrally located at the tetramer interface that is generated by the insertion of an amino acid in a conserved α4 h...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00544
更新日期:2018-07-31 00:00:00
abstract::The thermal unfolding of rabbit skeletal heavy meromyosin (HMM), myosin subfragment 1, and subfragment 2 has been studied by differential scanning calorimetry (DSC). Two distinct endotherms are observed in the DSC scan of heavy meromyosin. The first endotherm, with a Tm of 41 degrees C at pH 7.9 in 0.1 M KCl, is assig...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00462a018
更新日期:1990-03-13 00:00:00
abstract::The light-sensing outer segments of photoreceptor cells harbor hundreds of flattened membranous discs containing the visual pigment, rhodopsin, and all the proteins necessary for visual signal transduction. PRCD (progressive rod-cone degeneration) protein is one of a few proteins residing specifically in photoreceptor...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.6b00489
更新日期:2016-09-13 00:00:00
abstract::13C NMR spectroscopy was used to probe the structural interactions between carboxyl-13C-enriched oleic acid (18:1) and rat liver fatty acid binding protein (FABP) and the partitioning of 18:1 between FABP and unilamellar phosphatidylcholine (PC) vesicles. Spectra of systems containing 2-8 mol of 18:1/mol of FABP (but ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00402a033
更新日期:1988-01-26 00:00:00