Abstract:
:His12 and His119 are critical for catalysis of RNA cleavage by ribonuclease A (RNase A). Substitution of either residue with an alanine decreases the value of k(cat)/K(M) by more than 10(4)-fold. His12 and His119 are proximal to the scissile phosphoryl group of an RNA substrate in enzyme-substrate complexes. Here, the role of these active site histidines in RNA binding was investigated by monitoring the effect of mutagenesis and pH on the stability of enzyme-nucleic acid complexes. X-ray diffraction analysis of the H12A and H119A variants at a resolution of 1.7 and 1.8 A, respectively, shows that the amino acid substitutions do not perturb the overall structure of the variants. Isothermal titration calorimetric studies on the complexation of wild-type RNase A and the variants with 3'-UMP at pH 6.0 show that His12 and His119 contribute 1.4 and 1.1 kcal/mol to complex stability, respectively. Determination of the stability of the complex of wild-type RNase A and 6-carboxyfluorescein approximately d(AUAA) at varying pHs by fluorescence anisotropy shows that the stability increases by 2.4 kcal/mol as the pH decreases from 8.0 to 4.0. At pH 4.0, replacing His12 with an alanine residue decreases the stability of the complex with 6-carboxyfluorescein approximately d(AUAA) by 2.3 kcal/mol. Together, these structural and thermodynamic data provide the first thorough analysis of the contribution of histidine residues to nucleic acid binding.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Park C,Schultz LW,Raines RTdoi
10.1021/bi0100182subject
Has Abstractpub_date
2001-04-24 00:00:00pages
4949-56issue
16eissn
0006-2960issn
1520-4995pii
bi0100182journal_volume
40pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::This report describes the determination of the complete primary structure of the adhesin receptor polysaccharide of Streptococcus oralis ATCC 55229 (previously characterized as Streptococcus sanguis H1), a Gram-positive bacteria implicated in dental plaque formation. The polysaccharide was isolated from S. oralis ATCC...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00159a014
更新日期:1992-11-10 00:00:00
abstract::Information on the secondary structure and interactions of RNA is important to understand the biological function of RNA as well as in applying RNA as a tool for therapeutic purposes. Recently, the isoenergetic microarray mapping method was developed to improve the prediction of RNA secondary structure. Herein, for th...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi200463p
更新日期:2011-09-06 00:00:00
abstract::"Charged-to alanine" scanning mutagenesis of the catalytic subunit of the Saccharomyces cerevisiae cAMP-dependent protein kinase (C1) identified three glutamate residues, E171, E214, and E274, that are involved in the recognition of a peptide substrate, kemptide (Leu1Arg2Arg3Ala4Ser5Leu6Gly7). These glutamate residues...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00236a001
更新日期:1991-06-04 00:00:00
abstract::MerR, the metalloregulator of the mercury resistance (mer) operon, binds the operator (merO)between -10 and -35 of the merTPCAD promoter (PT) and sequesters RNA polymerase (RNAP) in a closed complex. MerR represses PT until Hg(II) induces it to underwind merO DNA and thus facilitate open complex formation. We used cro...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi982814m
更新日期:1999-03-16 00:00:00
abstract::Using solution peptide synthesis, we have made three series of N alpha-formylated homooligopeptides, from the dipeptide to the heptapeptide, derived from L-methionine, L-norleucine, and S-methyl-L-cysteine and related to the chemotactic peptide N alpha-formylmethionylleucylphenylalanine. Compounds were prepared to det...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00299a018
更新日期:1984-02-14 00:00:00
abstract::Filamins are a family of actin cross-linking proteins that are primarily localized in the cortical cytoplasm of all mammalian cells. Until now, three major isoforms (filamins a, b, and c) have been identified, that were shown to be differentially expressed and/or localized in different tissues. An amino-terminal doubl...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi026501+
更新日期:2003-01-21 00:00:00
abstract::Experimental measurements of the kinetic mechanism involving isoleucyl-tRNA synthetase proofreading valyl-tRNAIle in Escherichia coli have been incorporated into the conventional Michaelis-Menten model for this system. The model was subjected to a detailed mathematical analysis in the steady state. The results of this...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00303a019
更新日期:1984-04-10 00:00:00
abstract::Endothelium-derived epoxyeicosatrienoic acids (EETs) relax vascular smooth muscle by activating potassium channels and causing membrane hyperpolarization. Recent evidence suggests that EETs act via a membrane binding site or receptor. To further characterize this binding site or receptor, we synthesized 20-iodo-14,15-...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi102070w
更新日期:2011-05-10 00:00:00
abstract::Escherichia coli class Ib ribonucleotide reductase (RNR) converts nucleoside 5'-diphosphates to deoxynucleoside 5'-diphosphates in iron-limited and oxidative stress conditions. We have recently demonstrated in vitro that this RNR is active with both diferric-tyrosyl radical (Fe(III)(2)-Y(•)) and dimanganese(III)-Y(•) ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi101881d
更新日期:2011-03-15 00:00:00
abstract::Reactive amyloidosis occurs during chronic inflammation and involves deposition of amyloid A (AA) fibrils in many organs. Amyloid A is derived by proteolysis from serum amyloid A component (SAA), a major acute-phase reactant in many species. Since spontaneous amyloidosis occurs commonly in Syrian hamsters, we have stu...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00437a040
更新日期:1989-05-30 00:00:00
abstract::The interaction of poly(N epsilon, N epsilon, N epsilon-trimethyl-L-lysine) ([Lys(Me3)]n) and poly(N delta, N delta, N delta-trimethyl-L-ornithine) ([Orn(Me3)]n) with polynucleotides was studied by thermal denaturation, viscosity, and dissociation by salt. The methylated polymers decrease the viscosity of DNA in propo...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00555a020
更新日期:1980-07-08 00:00:00
abstract::Many lipases are potent catalysts of stereoselective reactions and are therefore of interest for use in chemical synthesis. The crystal structures of lipases show a large variation in the shapes of their active site environments that may explain the large variation in substrate specificity of these enzymes. We have de...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00051a035
更新日期:1995-12-26 00:00:00
abstract::Classical molecular dynamics simulations were utilized to investigate the structural and dynamical properties of water in the active site of ketosteroid isomerase (KSI) to provide insight into the role of these water molecules in the enzyme-catalyzed reaction. This reaction is thought to proceed via a dienolate interm...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi200703y
更新日期:2011-08-09 00:00:00
abstract::ArsR (or ArsR/SmtB) family metalloregulatory homodimeric repressors collectively respond to a wide range of metal ion inducers in regulating homeostasis and resistance of essential and nonessential metal ions in bacteria. BxmR from the cyanobacterium Osciliatoria brevis is the first characterized ArsR protein that sen...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi801313y
更新日期:2008-10-07 00:00:00
abstract::A specific, high-affinity binding site for ammodytoxin C in synaptic membranes from bovine cerebral cortex was detected and partially characterized. Equilibrium binding analysis revealed a single population of [125I]ammodytoxin C acceptors with the following binding parameters: Kd = 6.0 nM and Bmax = 5.7 pmol/mg membr...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00250a049
更新日期:1994-11-22 00:00:00
abstract::The unfolding equilibrium of recombinant (rNP) and natural variants of nucleoplasmin (NP) from Xenopus laevis has been analyzed using biochemical and spectroscopic techniques. In the presence of denaturing concentrations of guanidinium salts (GuHCl and GuSCN), both domains, core and tail, of the rNP pentamer unfold as...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi8002555
更新日期:2008-07-29 00:00:00
abstract::The influenza M2 proton channel is a major drug target, but unfortunately, the acquisition of resistance mutations greatly reduces the functional life span of a drug in influenza treatment. New M2 inhibitors that inhibit mutant M2 channels otherwise resistant to the early adamantine-based drugs have been reported, but...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.8b00722
更新日期:2018-10-16 00:00:00
abstract::The molecular organization of sterols in liposomes of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) at 37 degrees C is examined by utilizing the fluorescent analogue of cholesterol cholesta-5,7,9-trien-3 beta-ol (cholestatrienol). (1) Cholestatrienol is shown to be indistinguishable from native cholesterol i...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00456a027
更新日期:1990-01-30 00:00:00
abstract::In prokaryotes, the first three enzymes in pyrimidine biosynthesis, carbamoyl phosphate synthetase (CPS), aspartate transcarbamoylase (ATC), and dihydroorotase (DHO), are commonly expressed separately and either function independently (Escherichia coli) or associate into multifunctional complexes (Aquifex aeolicus). I...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi801831r
更新日期:2009-02-03 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::Beta2-microglobulin (beta2-m) can form dialysis-related amyloid deposits. The structure of a fragment of beta2-m (K3, Ser20-Lys41) in the oligomeric state has recently been solved. We modeled equilibrium structures of K3 oligomers with different organizations (single and double layers) and morphologies (linear-like an...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi7019194
更新日期:2008-02-26 00:00:00
abstract::Resonance Raman (RR) spectra of soluble guanylate cyclase (sGC) reported by five independent research groups have been classified as two types: sGC(1) and sGC(2). Here we demonstrate that the RR spectra of sGC isolated from bovine lung contain only sGC(2) while both species are observed in the spectra of the CO-bound ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0489208
更新日期:2005-01-25 00:00:00
abstract::The bacterial DNA cytosine methyltransferase M.HhaI sequence-specifically modifies DNA in an S-adenosylmethionine dependent reaction. The enzyme stabilizes the target cytosine (GCGC) into an extrahelical position, with a concomitant large movement of an active site loop involving residues 80-99. We used multidimension...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi602662e
更新日期:2007-06-19 00:00:00
abstract::Fesselin is a proline-rich actin-binding protein that was isolated from avian smooth muscle. Fesselin bundles actin and accelerates actin polymerization by facilitating nucleation. We now show that this polymerization of actin can be regulated by Ca(2+)-calmodulin. Fesselin was shown to bind to immobilized calmodulin ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0487490
更新日期:2004-11-02 00:00:00
abstract::Membrane fusion is involved in many fundamental cellular processes and entry of enveloped viruses into host cells. Influenza type A virus HA has long served as a paradigm for mechanistic studies of protein-mediated membrane fusion via large-scale structural rearrangements induced by acidic pH. Here we report the newly...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi401525h
更新日期:2014-02-11 00:00:00
abstract::LL-23 is a natural peptide corresponding to the 23 N-terminal amino acid residues of human host defense cathelicidin LL-37. LL-23 demonstrated, compared to LL-37, a conserved ability to induce the chemokine MCP-1 in human peripheral blood mononuclear cells, a lack of ability to suppress induction of the pro-inflammato...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi2016266
更新日期:2012-01-17 00:00:00
abstract::To clarify the function of the hydrophilic carboxyl-terminal tail of human erythrocyte membrane band 3 protein (HEM-B3), we purified two peptides, C1 (Ala893-Val911) and KS4 (Gly647-Arg656), from human erythrocyte band 3 protein preparations. Purified C1 peptides at concentrations from 5 to 80 microM were incubated wi...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi035281c
更新日期:2004-02-17 00:00:00
abstract::The SH3 and SH2 domains of hematopoietic cell kinase (Hck) play important roles in substrate targeting. To identify new components of Hck signaling pathways, we identified proteins that bind to the SH3 domain of Hck (Scott et al. (2002) J. Biol. Chem. 277, 28238). One such protein was ELMO1, the mammalian orthologue o...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi0500832
更新日期:2005-06-21 00:00:00
abstract::The triplet lifetime and absorption anisotropy decay of eosin-labeled band 3 was measured in resealed erythrocyte ghosts. Membrane potentials were generated by the addition of valinomycin in the presence of a K+ gradient. Neither negative nor positive membrane potentials had any detectable effect on the rotational dif...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00134a016
更新日期:1992-05-19 00:00:00
abstract::Hepatic mixed-function oxidase metabolism of the ubiquitous pollutant polychlorinated biphenyls (PCBs) is implicated in their toxification and detoxification. We used dichlorobiphenyls (DCBs) as models to investigate the effect of the chloro substituent sites on this metabolism experimentally and by molecular orbital ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00529a009
更新日期:1981-12-22 00:00:00