Abstract:
:Yah1p, an [Fe 2S 2]-containing ferredoxin located in the matrix of Saccharomyces cerevisiae mitochondria, functions in the synthesis of Fe/S clusters and heme a prosthetic groups. EPR, Mossbauer spectroscopy, and electron microscopy were used to characterize the Fe that accumulates in Yah1p-depleted isolated intact mitochondria. Gal- YAH1 cells were grown in standard rich media (YPD and YPGal) under O 2 or argon atmospheres. Mitochondria were isolated anaerobically, then prepared in the as-isolated redox state, the dithionite-treated state, and the O 2-treated state. The absence of strong EPR signals from Fe/S clusters when Yah1p was depleted confirms that Yah1p is required in Fe/S cluster assembly. Yah1p-depleted mitochondria, grown with O 2 bubbling through the media, accumulated excess Fe (up to 10 mM) that was present as 2-4 nm diameter ferric nanoparticles, similar to those observed in mitochondria from yfh1Delta cells. These particles yielded a broad isotropic EPR signal centered around g = 2, characteristic of superparamagnetic relaxation. Treatment with dithionite caused Fe (3+) ions of the nanoparticles to become reduced and largely exported from the mitochondria. Fe did not accumulate in mitochondria isolated from cells grown under Ar; a significant portion of the Fe in these organelles was in the high-spin Fe (2+) state. This suggests that the O 2 used during growth of Gal- YAH1 cells is responsible, either directly or indirectly, for Fe accumulation and for oxidizing Fe (2+) --> Fe (3+) prior to aggregation. Models are proposed in which the accumulation of ferric nanoparticles is caused either by the absence of a ligand that prevents such precipitation in wild-type mitochondria or by a more oxidizing environment within the mitochondria of Yah1p-depleted cells exposed to O 2. The efficacy of reducing accumulated Fe along with chelating it should be considered as a strategy for its removal in diseases involving such accumulations.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Miao R,Martinho M,Morales JG,Kim H,Ellis EA,Lill R,Hendrich MP,Münck E,Lindahl PAdoi
10.1021/bi801047qsubject
Has Abstractpub_date
2008-09-16 00:00:00pages
9888-99issue
37eissn
0006-2960issn
1520-4995journal_volume
47pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::Ligand-dependent site-site (or subunit-subunit) interactions provide the basis for explaining cooperativity in chemical reactions. Even in the simplest possible nonaggregating system, interpretation of the interactions in terms of structural details requires an explicit assumption (or model) for the binding of the lig...
journal_title:Biochemistry
pub_type: 杂志文章,评审
doi:10.1021/bi00106a004
更新日期:1991-10-22 00:00:00
abstract::The development of inhibitors of insulin-regulated aminopeptidase (IRAP), a membrane-bound zinc metallopeptidase, is a promising approach for the discovery of drugs for the treatment of memory loss such as that associated with Alzheimer's disease. There is, however, no consensus in the literature about the mechanism b...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi101893w
更新日期:2011-04-05 00:00:00
abstract::Because of the conflicting conclusions that have been reached regarding the location of the two putative membrane-spanning segments from cysteine 911 through isoleucine 929 and from isoleucine 946 through cysteine 964 in the alpha subunit of native ovine Na+/K(+)-transporting ATPase, the disposition of lysine 943 with...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00029a027
更新日期:1995-07-25 00:00:00
abstract::The cytokinin-active isoprenoid nucleosides of Agrobacterium tumefaciens transfer ribonucleic acid were identified by high-pressure liquid chromatography, permethylation, and mass spectroscopy. Besides the expected 6-[(3-methylbut-2-enyl)amino]-9-(beta-D-ribofuranosyl)purine (i6A) and its 2-methylthio derivative (ms2i...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00524a014
更新日期:1981-10-13 00:00:00
abstract::Tryptic digestion studies of the human erythrocyte glucose carrier have shown that a reactive and transport-sensitive exofacial sulfhydryl is located in the carboxy-terminal half of the molecule, corresponding to Cys347, Cys421, or Cys429. In the present studies, the erythrocyte glucose carrier labeled on the exofacia...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00497a014
更新日期:1990-11-13 00:00:00
abstract::We have analyzed the role of several protein motifs in controlling the membrane association of the xlcaax-1 protein in Xenopus oocytes. Xlcaax-1 is a maternally expressed protein that during development is associated with the basal lateral membrane of polarized epithelial cells. It is enriched in the tubule cells of t...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00083a022
更新日期:1993-08-17 00:00:00
abstract::Bacteriophage T7 RNA polymerase is a single-subunit enzyme which has a C-terminal amino acid sequence of Phe-Ala-Phe-Ala883 (FAFA883). Closely related hydrophobic sequences are present at the C termini of seven other single-subunit RNA polymerases, including the mitochondrial RNA polymerase. Mutations at any of the fo...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi962397i
更新日期:1997-03-11 00:00:00
abstract::Over 155 mutations within the V2 vasopressin receptor (AVPR2) gene are responsible for nephrogenic diabetes insipidus (NDI). The expression and subcellular distribution of four of these was investigated in transfected cells. These include a point mutation in the seventh transmembrane domain (S315R), a frameshift mutat...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi002699r
更新日期:2001-06-12 00:00:00
abstract::Binding of 125I-labeled human alpha-thrombin to endothelial cells derived from bovine corneas was studied in tissue culture. Specific and saturable binding to the cell surface occurred at 37 degrees C but to a much smaller extent at 4 degrees C. Binding of [125I]thrombin to a specific site on these cells with formatio...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00505a027
更新日期:1981-01-20 00:00:00
abstract::NAD(P) aldehyde dehydrogenases (EC 1.2.1.3) are a family of enzymes that oxidize a wide variety of aldehydes into acid or activated acid compounds. Using site-directed mutagenesis, the essential nucleophilic Cys 149 in the NAD-dependent phosphorylating glyceraldehyde-3-phosphate dehydrogenase from Escherichia coli has...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00164a033
更新日期:1992-12-15 00:00:00
abstract::Second-harmonic light scattering (SHS) permits characterization of membrane-specific molecular transport in living cells. Herein, we demonstrate the use of time-resolved SHS for quantifying chemically induced enhancements in membrane permeability. As proof of concept, we examine the enhanced permeability of the cytopl...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.5b00600
更新日期:2015-07-28 00:00:00
abstract::[1-Penicillamine,2-leucine]oxytocin is a conformationally restricted analogue of oxytoxin in which the half-cystine-1 and tyrosine-2 residues of the native hormone are replaced by half-penicillamine (beta, beta-dimethyl-half-cystine) and leucine, respectively. This analogue is a surprisingly potent oxytocin antagonist...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00513a018
更新日期:1981-05-12 00:00:00
abstract::We have used nucleoside phosphorothioates (NTP alpha S) and a substitution-interference method to identify phosphate oxygens that appear to be important to guanosine cofactor addition in the self-splicing group I intron from Tetrahymena thermophila. For the majority of these phosphate oxygens, however, the effect of N...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00068a001
更新日期:1993-05-04 00:00:00
abstract::Retinal rod and cone cGMP phosphodiesterases (PDE6 family) function as the effector enzyme in the vertebrate visual transduction cascade. The activity of PDE6 catalytic subunits is controlled by the Pgamma-subunits. In addition to the inhibition of cGMP hydrolysis at the catalytic sites, Pgamma is known to stimulate a...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi015935m
更新日期:2002-03-26 00:00:00
abstract::The enzyme kinetics of the reduction of the substrate 6,8-dimethylpterin by chicken and recombinant human dihydrofolate reductases (DHFRs) have been examined over the pH range 5.0-8.0 in the presence of NADPH or (4R)-[2H]NADPH (NADPD). The pH profiles of the catalytic constant (Vmax/[E]o or kcat) showed pH independenc...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00011a031
更新日期:1995-03-21 00:00:00
abstract::Escherichia coli asparagine synthetase B (AS-B) catalyzes the synthesis of asparagine from aspartate, glutamine, and ATP. A combination of kinetic, isotopic-labeling, and stoichiometry studies have been performed to define the nature of nitrogen transfer mediated by AS-B. The results of initial rate studies were consi...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi981058h
更新日期:1998-09-22 00:00:00
abstract::Ultrafast laser spectroscopy techniques are used to measure the low-frequency vibrational coherence spectra and nitric oxide rebinding kinetics of Caldariomyces fumago chloroperoxidase (CPO). Comparisons of the CPO coherence spectra with those of other heme species are made to gauge the protein-specific nature of the ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi7025485
更新日期:2008-05-06 00:00:00
abstract::Isolated chloroplasts are capable of synthesizing chloroplast DNA in the presence of Mg2+ and deoxynucleoside triphosphates. The in vitro reaction proceeds for at least 60 min and is inhibited by KC1 and N-ethylmaleimide. Stretches of several hundred nucleotides in length are synthesized within an hour. Little or no i...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00257a014
更新日期:1982-07-06 00:00:00
abstract::The interactions of 4-thiouridine and 5-[(methylamino)methyl]-2-thiouridine in tRNA and of phosphorothioate esters in nucleic acids with an organomercurial have been investigated. For this purpose, an affinity electrophoretic system has been developed in which the mercury derivative has been covalently immobilized in ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00410a048
更新日期:1988-05-17 00:00:00
abstract::Phospholipase A2 from Naja naja naja venom (Indian cobra) undergoes a concentration-dependent aggregation, and at an assay concentration of 1 microgram mL-1, it exists as a monomer. However, there is some evidence that the enzyme is actually active as a dimer or higher order aggregate. Previous attempts to determine t...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00343a018
更新日期:1985-10-22 00:00:00
abstract::A panel of 10 hybridomas was assembled to assess the influence of various genetic and biological factors upon glycosylation of secreted monoclonal IgG. After exhaustive Pronase digestion of IgG, glycopeptides were characterized chromatographically by apparent size, charge, and concanavalin A (Con A)-Sepharose and Lens...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00429a065
更新日期:1989-02-07 00:00:00
abstract::Mutations in the Kirsten ras (KRAS) gene are present in almost all pancreatic adenocarcinomas, and one common mutation is at codon 12: GGT (Gly) is transformed into GAT (Asp). In this work we have targeted the KRAS coding sequence embracing the GAT mutation with a sense PNA molecule (P14), with the aim of downregulati...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0505215
更新日期:2005-08-09 00:00:00
abstract::Nine monoclonal antibodies were used to test calcium and EDTA effects on the molecular conformation of ventricular VLC2 within myosin. Antibody epitopes were located in six domains of VLC2 using recombinant proteins. The apparent association constants of these antibodies were measured in solution in the presence of ca...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00208a005
更新日期:1994-10-25 00:00:00
abstract::Light-induced activation of the LOV2-Jα domain of the photoreceptor phototropin from oat is believed to involve the detachment of the Jα helix from the central β-sheet and its subsequent unfolding. The dynamics of these conformational changes were monitored by time-resolved emission spectroscopy with 100 ns time resol...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi101413v
更新日期:2010-12-28 00:00:00
abstract::The crystal structures of the deoxy and carbonmonoxy forms of a distal pocket myoglobin mutant in which valine68(E11) is replaced by threonine have been solved to 2.1- and 2.2-A resolution, respectively. This substitution has been shown previously to cause large decreases in the rate of oxygen binding and to lower the...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00211a016
更新日期:1993-12-07 00:00:00
abstract::The Hsp70-class molecular chaperone HscA interacts specifically with a conserved (99)LPPVK(103) motif of the iron-sulfur cluster scaffold protein IscU. We used a cellulose-bound peptide array to perform single-site saturation substitution of peptide residues corresponding to Glu(98)-Ile(104) of IscU to determine posit...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0606187
更新日期:2006-07-04 00:00:00
abstract::The early redox events involved in iron reduction and mobilization in mammalian ferritin have been investigated by several techniques. Sedimentation velocity measurements of ferritin samples with altered core sizes, prepared by partial reduction and Fe2+ chelation, suggest two different events occur during iron loss f...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00430a033
更新日期:1989-02-21 00:00:00
abstract::The membrane stabilization effect of cholesteryl hemisuccinate (CHEMS) and the sensitivity of the CHEMS-phosphatidylethanolamine membranes to protons and calcium ions were studied by differential scanning calorimetry, freeze-fracture electron microscopy, and 31P NMR. (1) At neutral pH, the addition of 8 mol % CHEMS to...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00328a013
更新日期:1985-03-26 00:00:00
abstract::In the present report we studied the interaction between the skeletal muscle ryanodine receptor and the ubiquitous S100A1 Ca2+ binding protein. S100A1 did not affect equilibrium [3H]ryanodine binding to purified rabbit skeletal muscle terminal cisternae at 100 microM free [Ca2+]. At nanomolar free [Ca2+], however, S10...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi970160w
更新日期:1997-09-23 00:00:00
abstract::The Gbeta and Ggamma subunit of the heterotrimeric G proteins form a functional dimer that is stable once assembled in vivo or in vitro. The requirements, mechanism, and specificity of dimer formation are still incompletely understood, but represent important biochemical processes involved in the specificity of cellul...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0504254
更新日期:2005-09-06 00:00:00