Abstract：
:Studies were undertaken to assess the postulated involvement of subunit III in the proton-linked functions of cytochrome c oxidase. The effect of pH on the steady-state kinetic [corrected] parameters of subunit III containing and subunit III depleted cytochrome oxidase was determined by using beef heart and rat liver enzymes reconstituted into phospholipid vesicles. The TNmax and Km values for the III-containing enzyme increase with decreasing pH in a manner quantitatively similar to that reported by Thornstrom et al. [(1984) Chem. Scr. 24, 230-235], giving three apparent pKa values of less than 5.0, 6.2, and 7.8. The maximal activities of the subunit III depleted enzymes (beef heart and rat liver) show a similar dependence on pH, but the Km values are consistently higher than those of the III-containing enzyme, an effect that is accentuated at low pH. The pH dependence of TNmax/Km for both forms of the enzyme (+/- subunit III) indicates that protonation of a group with an apparent pKa of 5.7 lowers the affinity for substrate (cytochrome c) independently of a continued increase in maximal velocity. N,N'-Dicyclohexylcarbodiimide (DCCD) decreases the pH responsiveness of the electron-transfer activity to the same extent in both III-containing and III-depleted enzymes, indicating that this effect is mediated by a peptide other than subunit III. Control of intramolecular electron transfer by a transmembrane pH gradient (or alkaline intravesicular pH) is shown to occur in cytochrome oxidase vesicles with cytochrome c as the electron donor, in agreement with results of Moroney et al. [(1984) Biochemistry 23, 4991-4997] using hexaammineruthenium(II) as the reductant.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
Biochemistryjournal_title
Biochemistryauthors
Gregory LC,Ferguson-Miller Sdoi
10.1021/bi00417a016subject
Has Abstractpub_date
1988-08-23 00:00:00pages
6307-14issue
17eissn
0006-2960issn
1520-4995journal_volume
27pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract：:Cuprizone intoxication is a common animal model used to test myelin regenerative therapies for the treatment of diseases such as multiple sclerosis. Mice fed this copper chelator develop reversible, region-specific oligodendrocyte loss and demyelination. While the cellular changes influencing the demyelinating process...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.6b01072
更新日期：2017-03-14 00:00:00
abstract：:Molecular dynamics simulations employing a molecular mechanics (MM) force field and hybrid quantum mechanics (QM) and MM (QM/MM) have been carried out to investigate the product specificity and mechanism of the histone H4 lysine 20 (H4-K20) methylation by human histone lysine methyltransferase SET8. At neutral pH, the...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi800244s
更新日期：2008-06-24 00:00:00
abstract：:The interactions of two plant annexins, annexin 24(Ca32) from Capsicum annuum and annexin Gh1 from Gossypium hirsutum, with phospholipid membranes have been characterized using liposome-based assays and adsorption to monolayers. These two plant annexins show a preference for phosphatidylserine-containing membranes and...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi0516226
更新日期：2005-12-13 00:00:00
abstract：:Human methionine synthase reductase (MSR), a diflavin oxidoreductase, plays a vital role in methionine and folate metabolism by sustaining methionine synthase (MS) activity. MSR catalyzes the oxidation of NADPH and shuttles electrons via its FAD and FMN cofactors to inactive MS-cob(II)alamin. A conserved aromatic resi...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi2012228
更新日期：2011-12-27 00:00:00
abstract：:The interaction of bleomycin A2 with DNA has been examined by fluorescence spectroscopy and proton magnetic resonance techniques. Fluorescence bands observed at 353 and 405 nm in the spectrum of bleomycin were assigned to the bithiazole and 4-aminopyrimidine rings, respectively. Quenching of bithiazole fluorescence by...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00635a021
更新日期：1977-08-09 00:00:00
abstract：:Thermodynamic data for RNA 1 x 2 nucleotide internal loops are lacking. Thermodynamic data that are available for 1 x 2 loops, however, are for loops that rarely occur in nature. In order to identify the most frequently occurring 1 x 2 nucleotide internal loops, a database of 955 RNA secondary structures was compiled ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi701024w
更新日期：2007-12-18 00:00:00
abstract：:A chromatin acceptor protein for the avian oviduct progesterone receptor (PR), termed receptor binding factor 1 (RBF-1), has recently been shown to (1) be a component of the nuclear binding sites (acceptor sites) for PR and (2) generate high-affinity binding sites (termed the RBF-1 class of sites) on avian genomic DNA...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00103a019
更新日期：1991-10-01 00:00:00
abstract：:The bacteriophage T7 DNA helicase/primase (gene 4 protein) is a ring-like hexamer that encircles ssDNA and requires forked DNA to catalyze DNA unwinding. We report that optimal rates of unwinding of forked DNA require ssDNA tails of 55 nucleotides on the 5'-to-3' strand and 15 nucleotides on the 3'-to-5' strand. Surpr...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi971644v
更新日期：1997-11-18 00:00:00
abstract：:Sir2 protein deacetylases (or sirtuins) catalyze NAD+-dependent conversion of epsilon-amino-acetylated lysine residues to deacetylated lysine, nicotinamide, and 2'-O-acetyl-ADP-ribose. Small-molecule modulation of sirtuin activity might treat age-associated diseases, such as type II diabetes, obesity, and neurodegener...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi7013294
更新日期：2007-12-18 00:00:00
abstract：:We have found a correlation between liposome fusion kinetics and lipid phase behavior for several inverted phase forming lipids. N-Methylated dioleoylphosphatidylethanolamine (DOPE-Me), or mixtures of dioleoylphosphatidylethanolamine (DOPE) and dioleoylphosphatidylcholine (DOPC), will form an inverted hexagonal phase ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00435a011
更新日期：1989-05-02 00:00:00
abstract：:Protein kinase C and two other proteins with molecular masses of 64 and 32 kDa, purified from bovine brain, constitute a type of protein that binds a large number of calcium ions in a phospholipid-dependent manner. This study suggested that these proteins also induced extensive clustering of acidic phospholipids in th...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00246a013
更新日期：1991-08-13 00:00:00
abstract：:The active form of the animal fatty acid synthase (FAS) is a dimer of identical multifunctional polypeptides, each containing seven discrete functional domains, that cooperate to form two centers for palmitate synthesis. To assess the importance of domain cooperation across the subunit interface in the reaction mechan...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi971886v
更新日期：1998-02-24 00:00:00
abstract：:The trifunctional dinuclear platinum compounds 1,2/c,c [[cis-PtCl(NH(3))(2)]mu-H(2)N(CH(2))(6)NH(2)[cis-PtCl(2)(NH(3))]](+) and 1,2/t,c [[trans-PtCl(NH(3))(2)]mu-H(2)N(CH(2))(6)NH(2)[cis-PtCl(2)(NH(3))]](+) contain a monofunctional platinum coordination sphere linked to a cis-[PtCl(2)(amine)(2)] moiety. The compounds ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi030243e
更新日期：2004-06-22 00:00:00
abstract：:Structures of several voltage-gated sodium (NaV) channels from bacteria have been determined recently, but the same feat might not be achieved for the mammalian counterparts in the near future. Thus, at present, computational studies of the mammalian NaV channels have to be performed using homology models based on the...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.5b01324
更新日期：2016-03-29 00:00:00
abstract：:Piscidin 1 (Pis-1) is a novel cytotoxic peptide with a cationic alpha-helical structure that was isolated from the mast cells of hybrid striped bass [Silphaduang, U., and Noga, E. J. (2001) Nature 414, 268-269]. Pis-1 is not selective for bacterial versus mammalian cells. In the present study, to develop novel antibio...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi062233u
更新日期：2007-03-27 00:00:00
abstract：:Sulfenic acid is formed upon oxidation of thiols and is a central intermediate in the redox modulation of an increasing number of proteins. Methods for quantifying or even detecting sulfenic acid are scarce. Herein, the reagent 7-chloro-4-nitrobenz-2-oxa-1,3-diazole was determined not to be suitable as a chromophoric ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi701520y
更新日期：2008-01-08 00:00:00
abstract：:G-protein-coupled receptors (GPCRs) have evolved as highly specialized cellular machinery that can dictate biological outcomes in response to diverse stimuli. Specifically, they induce multiple pathway responses upon structural perturbations induced at local protein sites. GPCRs utilize a concurrent strategy involving...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.9b00884
更新日期：2020-01-28 00:00:00
abstract：:We report cloning, expression in Escherichia coli, and purification of cytochrome P450 from a deep-sea bacterium Photobacterium profundum strain SS9 (P450-SS9). The enzyme, which is predominately high spin (86%) in the absence of any added ligand, binds fatty acids and their derivatives and exhibits the highest affini...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi101466y
更新日期：2010-12-21 00:00:00
abstract：:Acarbose is a naturally occurring pseudo-tetrasaccharide. It has been used in conjunction with other drugs in the treatment of diabetes where it acts as an inhibitor of intestinal glucosidases. To probe the interactions of acarbose with other carbohydrate recognition enzymes, the crystal structure of E. coli maltodext...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi9828573
更新日期：1999-04-27 00:00:00
abstract：:Spectroscopic characterization of the newly discovered heme-PAS domain sensor protein BxRcoM-2 reveals that this protein undergoes redox-dependent ligand switching and CO- and NO-induced ligand displacement. The aerobic bacterium Burkholderia xenovorans expresses two homologous heme-containing proteins that promote CO...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi800486x
更新日期：2008-08-26 00:00:00
abstract：:The regulatory (R) subunit of cAMP-dependent protein kinase (cAPK) is a multidomain protein with two tandem cAMP-binding domains, A and B. The importance of cAMP binding on the stability of the R subunit was probed by intrinsic fluorescence and circular dichroism (CD) in the presence and absence of urea. Several mutan...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi001563q
更新日期：2000-12-12 00:00:00
abstract：:Alpha-synuclein (alphaS) is a lipid-binding synaptic protein of unknown function that is found in an aggregated amyloid fibril form in the intraneuronal Lewy body deposits that are a defining characteristic of Parkinson's disease (PD). Although intrinsically unstructured when free in solution, alphaS adopts a highly h...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi036135+
更新日期：2004-04-27 00:00:00
abstract：:Enolase is a glycolytic metalloenzyme involved in carbon metabolism. The advantage of targeting enolase lies in its essentiality in many biological processes such as cell wall formation and RNA turnover and as a plasminogen receptor. We initially used a DARTS assay to identify enolase as a target in Escherichia coli. ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/acs.biochem.8b01298
更新日期：2019-03-05 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：:To generate an effective immune response, class II major histocompatibility complex molecules (MHCII) must present a diverse array of peptide ligands for recognition by T lymphocytes. Peptide/MHCII complexes are stabilized by hydrophobic anchoring of peptide side chains to pockets in the MHCII protein and the formatio...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi048675s
更新日期：2005-04-19 00:00:00
abstract：:The value of reducing the activity of ornithine decarboxylase (ODC), a key enzyme in the biosynthesis of polyamines, is well-appreciated. Polyamines are necessary components for cell growth, and manipulation of polyamine homeostasis may be an effective strategy for the treatment of a number of disorders, including neo...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi047918d
更新日期：2005-02-15 00:00:00
abstract：:Four different temperature-sensitive M protein mutants (tsM) of vesicular stomatitis virus (VSV) were characterized with regard to the association of the mutated M protein either with nucleocapsids or with membranes in the intact virions. Virions were labeled with the photoreactive hydrophobic probe [125I]iodonaphthyl...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00527a020
更新日期：1981-11-24 00:00:00
abstract：:Standard preparations of Escherichia coli RNA polymerase harbor a 70 kDa protein with NTPase (beta-gamma cleavage) activity that is not a recognized polymerase subunit. The NTPase activity of this component, before and after separation from the polymerase, is strongly dependent on the presence of DNA; single-stranded ...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi970191r
更新日期：1997-12-02 00:00:00
abstract：:The qualitative and quantitative features of mutagenesis by two DNA adducts of carcinogenic alkylating agents, O6-methylguanine (m6G) and O4-methylthymine (m4T), were examined in vivo. The deoxyhexanucleotides 5'-GCTAGC-3' and 5'-GCTAGC-3' were synthesized, where the underlined bases are the positions of m4T or m6G, r...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00242a031
更新日期：1991-07-16 00:00:00
abstract：:Electron paramagnetic resonance (EPR) measurements were performed on photosystem II (PSII) membranes that were treated with 2 M NaCl to release the 17- and 23-kilodalton (kDa) polypeptides. By using 75 microM 3-(3,4-dichlorophenyl)-1,1-dimethylurea to limit the photosystem II samples to one stable charge separation in...
journal_title：Biochemistry
pub_type： 杂志文章
doi：10.1021/bi00369a022
更新日期：1986-10-21 00:00:00
