Phosphorescence from 2-(p-toluidinyl)naphthalene-6-sulfonate and 1-anilinonaphthalene-8-sulfonate, commonly used fluorescence probes of biological structures.
AuthorsManiara G, Vanderkooi JM, Bloomgarden DC, Koloczek H
JournalPhotochem Photobiol
PubMed ID3344289
Resolution of multicomponent fluorescence emission by phase sensitive detection at multiple modulation frequencies.
AuthorsKeating-Nakamoto SM, Cherek H, Lakowicz JR
JournalAnal Chem
PubMed ID3619043
Interactions of phosphatidylcholine vesicles with 2-p-toluidinylnaphthalene-6-sulfonate.
AuthorsHuang CH, Charlton JP
JournalBiochemistry
PubMed ID5062144
Inhibition of ADP-induced aggregation of bovine platelets by saturated fatty acids and its relation with the change of membrane surface charge.
AuthorsKitagawa S, Nishitama H, Kametani F
JournalBiochim Biophys Acta
PubMed ID6466668
'The inhibitory effects of saturated fatty acids with 4 to 18 carbon atoms on ADP-induced aggregation of bovine platelets were investigated. The inhibitory effects of the acids increased with increase of their alkyl chain length up to C14. On the other hand, from C16 the inhibitory effects tended to decrease ... More
Interaction of membrane surface charges with the reconstituted ADP/ATP-carrier from mitochondria.
AuthorsKrämer R
JournalBiochim Biophys Acta
PubMed ID6313053
'Various modulating influences of negative and positive membrane charges on binding and transport properties of the reconstituted ADP/ATP carrier from mitochondria were investigated. The results are interpreted in terms of functional and structural asymmetries of the adenine nucleotide carrier embedded in the liposomal membrane. The surface potential of liposomes was ... More
The crystallographic structure of phytohemagglutinin-L.
'The structure of phytohemagglutinin-L (PHA-L), a leucoagglutinating seed lectin from Phaseolus vulgaris, has been solved with molecular replacement using the coordinates of lentil lectin as model, and refined at a resolution of 2.8 A. The final R-factor of the structure is 20.0%. The quaternary structure of the PHA-L tetramer differs ... More
A fluorescent probe study of salmine AI.
AuthorsRusso SF, Engel RG
JournalPhysiol Chem Phys
PubMed ID569339
'A fluorescent probe, 1-p-toluidinylnapthalene-8-sulfonate (1,8-TNS), was used to study the nonpolar sites on salmine AI. Fluorescence enhancement resulting from binding between the probe and the protein occurs at a wavelength of maximum emission of 497-500 nm, indicating the existence of moderately nonpolar binding sites on salmine AI.Fluorescence enhancement decreases as ... More
Determination of time-resolved fluorescence emission spectra and anisotropies of a fluorophore-protein complex using frequency-domain phase-modulation fluorometry.
AuthorsLakowicz JR, Gratton E, Cherek H, Maliwal BP, Laczko G
JournalJ Biol Chem
PubMed ID6469993
'We report the first time-resolved fluorescence emission spectra and time-resolved fluorescence anisotropies obtained using frequency-domain fluorescence spectroscopy. We examined the fluorophore p-2-toluidinyl-6-naphthalenesulfonic acid (TNS) in viscous solvents and bound to the heme site of apomyoglobin using multifrequency phase fluorometers. Fluorescence phase shift and modulation data were obtained at modulation frequencies ... More
The location of fluorescence probes with charged groups in model membranes.
AuthorsKachel K, Asuncion-Punzalan E, London E
JournalBiochim Biophys Acta
PubMed ID9814853
'The location of commonly used charged fluorescent membrane probes in membranes was determined in order to: (1) investigate the relationship between the structure of hydrophobic molecules and their depth within membranes; and (2) aid interpretation of experiments in which these fluorescent probes are used to examine membrane structure. Membrane depth ... More
Fluorescent probes as a measure of conformational alterations induced by nucleophilic modification and proteolysis of bovine alpha 2-macroglobulin.
'Conformational alterations occurring in bovine alpha 2-macroglobulin (alpha 2M) resulting from proteolysis and nucleophilic modification have been monitored by UV difference spectra, circular dichroism, and changes in the fluorescence of 6-(p-toluidino)-2-naphthalenesulfonate (TNS) and bis(8-anilino-1-naphthalenesulfonate) (Bis-ANS). The results of this study indicate that these two dyes appear capable of differentiating between ... More
Reactions of fluorescent probes with normal and chemically modified myelin.
AuthorsFeinstein MB, Felsenfeld H
JournalBiochemistry
PubMed ID238581
'The fluorescent probes 8-anilino-1-naphthalenesulfonate (ANS) and 2-p-toluidinylnaphthalene-6-sulfonate (TNS) bind to highly purified myelin membranes obtained from bovine brain white matter. Binding of the dyes was markedly increased by environmental conditions which reduce the negative surface potential of the membrane, i.e., cations (La-3+ is greater than Ca-2+ is greater than Na-+,K-+), ... More
High-density miniaturized thermal shift assays as a general strategy for drug discovery.
AuthorsPantoliano MW, Petrella EC, Kwasnoski JD, Lobanov VS, Myslik J, Graf E, Carver T, Asel E, Springer BA, Lane P, Salemme FR
JournalJ Biomol Screen
PubMed ID11788061
'More general and universally applicable drug discovery assay technologies are needed in order to keep pace with the recent advances in combinatorial chemistry and genomics-based target generation. Ligand-induced conformational stabilization of proteins is a well-understood phenomenon in which substrates, inhibitors, cofactors, and even other proteins provide enhanced stability to proteins ... More
Fluorescence spectroscopic investigations of the dynamic properties of proteins, membranes and nucleic acids.
AuthorsLakowicz JR
JournalJ Biochem Biophys Methods
PubMed ID6158533
'Fluorescence spectroscopy can reveal the dynamic properties of proteins, membranes and nucleic acids on the nanosecond timescale. Dynamic processes which can affect the fluorescence spectral characteristics of biopolymer-bound fluorophores include dipolar relaxation around excited state dipoles, rotational diffusion of fluorophores, and permeation of bipolymers of fluorescence quenchers. The occurrence of ... More
Analysis of excited-state processes by phase-modulation fluorescence spectroscopy.
AuthorsLakowicz JR, Balter A
JournalBiophys Chem
PubMed ID7139044
'Fluorescence phase shift and demodulation methods were used in the analysis of excited-state reactions and to investigate solvent relaxation around fluorophores in viscous solvents. The chosen samples illustrate the results expected for fluorophores bound to biological macromolecules. These moderately simple samples served to test the theoretical predictions described in the ... More
Fluorescent probes for measuring the binding constants and distances between the metal ions bound to Escherichia coli glutamine synthetase.
AuthorsLin WY, Eads CD, Villafranca JJ
JournalBiochemistry
PubMed ID1672822
'TNS, 2-p-toluidinylnaphthalene-6-sulfonate, has been used as a fluorescent probe to determine the binding constants of metal ions to the two binding sites of Escherichia coli glutamine synthetase (GS). TNS fluorescence is enhanced dramatically when bound to proteins due to its high quantum yield resulting from its interactions with hydrophobic regions ... More
Fluorescence spectroscopic studies of Huntington fibroblast membranes.
AuthorsLakowicz JR, Sheppard JR
JournalAm J Hum Genet
PubMed ID6452057
'Using fluorescence spectroscopic methods, we compared the membrane properties of intact fibroblasts from both normal subjects and patients with Huntington disease (HD). Cells were stained with various fluorophores, including 1-anilino-8-naphthalene sulfonic acid (ANS), 2-toluidinyl-6-naphthalene sulfonic acid (TNS), 1,6-diphenyl-1,3,5-hexatriene (DPH), and 6-lauroyl-2-(dimethylamino)-naphthalene (LAURDAN). Using these labeled cells, we measured fluorescence yields ... More
S100A13. Biochemical characterization and subcellular localization in different cell lines.
AuthorsRidinger K, Schäfer BW, Durussel I, Cox JA, Heizmann CW
JournalJ Biol Chem
PubMed ID10722710
'S100 proteins became of major interest because of their divergent cell- and tissue-specific expression, their close association with a number of human diseases, and their importance for clinical diagnostics. Here, we report for the first time the purification and characterization of human recombinant S100A13. Flow dialysis revealed that the homodimeric ... More
Nonclassical hydrophobic effect in membrane binding equilibria.
AuthorsSeelig J, Ganz P
JournalBiochemistry
PubMed ID1832558
'The enthalpy of transfer of four different amphiphilic molecules from the aqueous phase to the lipid membrane was determined by titration calorimetry. The four molecules investigated were the potential-sensitive dye 2-(p-toluidinyl)naphthalene-6-sulfonate (TNS), the membrane conductivity inducing anion tetraphenylborate (TPB), the Ca2+ channel blocker amlodipine [Bäuerle, H. D., & Seelig, J. ... More
An experimental test of the discreteness-of-charge effect in positive and negative lipid bilayers.
AuthorsWiniski AP, McLaughlin AC, McDaniel RV, Eisenberg M, McLaughlin S
JournalBiochemistry
PubMed ID3814579
'The electrostatic properties of charged bilayers and the bilayer component of biological membranes are often described theoretically by assuming the charge is smeared uniformly over the surface. This is one of the fundamental assumptions in the Gouy-Chapman-Stern (GCS) theory. However, the average distance between the charged phospholipids in a typical ... More
Comparison of the Ca2+-binding properties of human recombinant calretinin-22k and calretinin.
AuthorsSchwaller B, Durussel I, Jermann D, Herrmann B, Cox JA
JournalJ Biol Chem
PubMed ID9368033
'Calretinin-22k (CR-22k) is a splice product of calretinin (CR) found specifically in cancer cells, and possesses four EF-hands and a differently processed C-terminal end. The Ca2+-binding properties of recombinant human calretinin CR-22k were investigated by flow dialysis and spectroscopic methods and compared with those of CR. CR possesses four Ca2+-binding ... More
Phase-sensitive fluorescence spectroscopy: a new method to resolve fluorescence lifetimes or emission spectra of components in a mixture of fluorophores.
AuthorsLakowicz JR, Cherek H
JournalJ Biochem Biophys Methods
PubMed ID7276422
'A novel phase fluorometric method is described which permits direct recording of individual emission spectra from a mixture of two fluorescent compounds. Additionally, the lifetimes of each component may be determined by examination of the phase-sensitive fluorescence spectra. The method utilizes phase-sensitive detection of the sinusoidally modulated emission from a ... More
Determination of depolymerization kinetics of amylose, amylopectin, and soluble starch by Aspergillus oryzae alpha-amylase using a fluorimetric 2-p-toluidinylnaphthalene-6-sulfonate/flow-injection analysis system.
AuthorsBatlle N, Carbonell JV, Sendra JM
JournalBiotechnol Bioeng
PubMed ID11042551
'This study reports on the determination of the depolymerization kinetics of amylose, amylopectin, and soluble starch by Aspergillus oryzae alpha-amylase using flow-injection analysis with fluorescence detection and 2-p-toluidinylnaphthalene-6-sulfonate as the fluorescent probe. The experimental data points, corresponding to the evolution of the concentration of "detectable" substrate with depolymerization time, were ... More
The role of active site residue arginine 218 in firefly luciferase bioluminescence.
AuthorsBranchini BR, Magyar RA, Murtiashaw MH, Portier NC
JournalBiochemistry
PubMed ID11327861
'Firefly luciferase catalyzes the highly efficient emission of yellow-green light from substrate firefly luciferin by a sequence of reactions that require Mg-ATP and molecular oxygen. We had previously developed a working model of the luciferase active site based on the X-ray structure of the enzyme without bound substrates. In our ... More
Effects of sialic acids and the beta-drug adrenergic blocker, propranolol, on the dynamics of human alpha 1-acid glycoprotein: a fluorescence study.
AuthorsAlbani JR
JournalJ Biochem (Tokyo)
PubMed ID7852282
'The effect of propranolol on the dynamics of human alpha 1-acid glycoprotein (orosomucoid) (sialylated and asialylated) was studied. 2-p-Toluidinylnaphthalene-6-sulfonate (TNS) bound to the protein was used as a probe. The results were identical for all samples. Excitation at the red edge of the absorption spectrum of TNS leads to an ... More
Identification of Ligand Binding by Protein Stabilization: Comparison of ATLAS with Biophysical and Enzymatic Methods.
AuthorsThompson PA, Wang S, Howett LJ, Wang MM, Patel R, Averill A, Showalter RE, Li B, Appleman JR,
JournalAssay Drug Dev Technol
PubMed ID18336087
'Abstract: ATLAS() (Any Target Ligand Affinity Screen) (Anadys Pharmaceuticals, Inc., San Diego, CA) is a homogeneous, affinity-based high-throughput screening technology based on protein thermal denaturation and the ability of ligands to bind and stabilize the target protein from unfolding. To further understand the assay sensitivity for the identification of ligands ... More
Electrostatics of phosphoinositide bilayer membranes. Theoretical and experimental results.
AuthorsLangner M, Cafiso D, Marcelja S, McLaughlin S
JournalBiophys J
PubMed ID2156577
'We made fluorescence, electron paramagnetic resonance (EPR), electrophoretic mobility, and ionizing electrode measurements to study the effect of the monovalent lipid phosphatidylinositol (PI) and the trivalent lipid phosphatidylinositol 4,5-bisphosphate (PIP2) on the electrostatic potential adjacent to bilayer membranes. When the membranes were formed from mixtures of PI and the zwitterionic ... More
Change in the protein tertiary structure with non-enzymatic glycosylation of calf alpha-crystallin.
AuthorsLiang JN, Chylack LT
JournalBiochem Biophys Res Commun
PubMed ID6487332
'Non-enzymatic glycosylation of calf alpha-crystallin was induced by incubation with glucose. Glycosylated and non-glycosylated proteins were separated by affinity chromatography on Glyco Gel B boronic acid and were studied by circular dichroism (CD) and fluorescence. CD indicated that the glycosylated protein secondary structure was not altered, but the tertiary structure ... More
Nanosecond dynamics of charged fluorescent probes at the polar interface of a membrane phospholipid bilayer.
AuthorsDemchenko AP, Shcherbatska NV
JournalBiophys Chem
PubMed ID4052570
'Molecular relaxation fluorescence methods were applied to analyze the nature and characteristic times of motions of amphiphilic molecules absorbed in the polar region of a phospholipid bilayer. The fluorescence probes 2-toluidinonaphthalene-6-sulfonate and 1-anilinonaphthalene-8-sulfonate in egg phosphatidylcholine vesicles were studied. The methods of edge excitation fluorescence red shifts, nanosecond time-resolved spectroscopy, ... More
ALG-2 interacts with the amino-terminal domain of annexin XI in a Ca(2+)-dependent manner.
AuthorsSatoh H, Shibata H, Nakano Y, Kitaura Y, Maki M
JournalBiochem Biophys Res Commun
PubMed ID11883939
'The apoptosis-linked protein ALG-2 is a Ca(2+)-binding protein that belongs to the penta-EF-hand protein family. ALG-2 forms a homodimer, a heterodimer with another penta-EF-hand protein, peflin, and a complex with its interacting protein, named AIP1 or Alix. By yeast two-hybrid screening using human ALG-2 as bait, we isolated a cDNA ... More
Cation binding and conformational changes in VILIP and NCS-1, two neuron-specific calcium-binding proteins.
AuthorsCox JA, Durussel I, Comte M, Nef S, Nef P, Lenz SE, Gundelfinger ED
JournalJ Biol Chem
PubMed ID7806504
'VILIP and NCS-1, neural-specific, 22-kDa Ca(2+)-binding proteins possessing four EF-hands, were expressed in Escherichia coli to study their divalent cation properties. Flow dialysis (Ca2+ binding) and equilibrium gel filtration (Mg2+ binding) revealed that both recombinant proteins possess only two active metal-binding sites, which can accommodate either Ca2+ or Mg2+. VILIP ... More
Hydrodynamics of horseradish peroxidase revealed by global analysis of multiple fluorescence probes.
AuthorsBrunet JE, Vargas V, Gratton E, Jameson DM
JournalBiophys J
PubMed ID8161698
'Previous fluorescence studies of horseradish peroxidase conjugated with protoporphyrin IX suggested that the protein behaved hydrodynamically as a prolate ellipsoid of axial ratio 3 to 1. The present study, designed to further investigate the hydrodynamics of this protein, exploits a series of probes, noncovalently bound to the heme binding site ... More
Rational design of cationic lipids for siRNA delivery.
AuthorsSemple SC, Akinc A, Chen J, Sandhu AP, Mui BL, Cho CK, Sah DW, Stebbing D, Crosley EJ, Yaworski E, Hafez IM, Dorkin JR, Qin J, Lam K, Rajeev KG, Wong KF, Jeffs LB, Nechev L, Eisenhardt ML, Jayaraman M, Kazem M, Maier MA, Srinivasulu M, Weinstein MJ, Chen Q, Alvarez R, Barros SA, De S, Klimuk SK, Borland T, Kosovrasti V, Cantley WL, Tam YK, Manoharan M, Ciufolini MA, Tracy MA, de Fougerolles A, MacLachlan I, Cullis PR, Madden TD, Hope MJ,
JournalNat Biotechnol
PubMed ID20081866
'We adopted a rational approach to design cationic lipids for use in formulations to deliver small interfering RNA (siRNA). Starting with the ionizable cationic lipid 1,2-dilinoleyloxy-3-dimethylaminopropane (DLinDMA), a key lipid component of stable nucleic acid lipid particles (SNALP) as a benchmark, we used the proposed in vivo mechanism of action ... More
Disruptive effects of tris and sodium lauroyl sarcosinate on the outer membrane of Pseudomonas cepacia shown by fluorescent probes.
AuthorsAnwar H, Brown MR, Britten AZ, Lambert PA
JournalJ Gen Microbiol
PubMed ID6195304
'The disruptive effects of Tris buffer and sodium lauroyl sarcosinate (Sarkosyl) on the outer membrane (OM) of Pseudomonas cepacia were investigated with several fluorescent probes. Tris increased the permeability of the OM to 6-anilino-l-naphthalenesulphonic acid and 2-p-toluidinylnaphthalene-6-sulphonate. The degree of damage to the OM was enhanced when the pH was ... More
Rotational modes of Ca2+-liganded calmodulin, as determined by time-domain fluorescence.
AuthorsSteiner RF, Norris L
JournalBiophys Chem
PubMed ID3607237
'The time decay of fluorescence anisotropy was monitored as a function of pH and temperature for complexes of 2,6-toluidinylnaphthalenesulfonate with calmodulin, with its proteolytic fragments, and with the 1:1 complex of calmodulin and melittin. For all the conditions examined the anisotropy decay of native calmodulin involved at least two rotational ... More
Fluorescent probes for conformational states of proteins. I. Mechanism of fluorescence of 2-p-toluidinylnaphthalene-6-sulfonate, a hydrophobic probe.
AuthorsMcClure WO, Edelman GM
JournalBiochemistry
PubMed ID4164420
Global analysis of multiple dye fluorescence anisotropy experiments on proteins.
AuthorsBeechem JM, Knutson JR, Brand L
JournalBiochem Soc Trans
PubMed ID3781080
Fluorescence spectroscopy of proteins.
AuthorsStryer L
JournalScience
PubMed ID5706935
Fluorophores in a polar medium: time dependence of emission spectra detected by multifrequency phase and modulation fluorometry.
AuthorsParasassi T, Conti F, Gratton E
JournalCell Mol Biol
PubMed ID3948209
Fluorescence probes for structure.
AuthorsBrand L, Gohlke JR
JournalAnnu Rev Biochem
PubMed ID4563443
Quantitative estimation of protein binding site polarity. Fluorescence of N-arylaminonaphthalenesulfonates.
AuthorsTurner DC, Brand L
JournalBiochemistry
PubMed ID5693059
Spectroscopic investigations of bovine lens crystallins. 2. Fluorescent probes for polar-apolar nature and sulfhydryl group accessibility.
AuthorsAndley UP, Liang JN, Chakrabarti B
JournalBiochemistry
PubMed ID7082651
Fluorescent probes in nerve membranes.
AuthorsConti F
JournalAnnu Rev Biophys Bioeng
PubMed ID1098558
Fluorophores as visualization aides in agar growth media.
AuthorsLepp CA, Nowlan ED, Mason RD, Ramsey WS
JournalExperientia
PubMed ID383493
A survey of 26 fluorophores revealed 5 which were non-inhibitory to Staphylococcus aureus and Escherichia coli and produced low background and high colony fluorescence.
Capillary electrophoresis of amino sugars with laser-induced fluorescence detection.
AuthorsLiu JP, Shirota O, Novotny M
JournalAnal Chem
PubMed ID2064007
3-(4-Carboxybenzoyl)-2-quinolinecarboxaldehyde has been utilized as a precolumn derivatization agent for various amino sugars. Constituents of various biological mixtures can be converted to highly fluorescent isoindole derivatives, separated by high-performance capillary electrophoresis and determined at attomole (10(-18) mol) levels by a laser-induced fluorescence detector. This method has been applied to the ... More
Intrinsic and extrinsic fluorescence of histones H2A and H2B: a conformational study.
AuthorsGiancotti V, Brovedan S, Fonda M, Grandinetti R, Russo E
JournalBiophys Chem
PubMed ID623868
Intrinsic and extrinsic fluorescence measurements suggest that H2A and H2B histones, in a partially secondary structure, self-aggregate into assemblies in which some tyrosine groups are buried in a hydrophobic environment and show enhanced fluorescence, 2-p-toluidinylnaphthalene-6-sulfonate (TNS) indicates heterogeneity among the binding sites whose number depends on the pH values of ... More
Compulsive attentive behavior after lesion of the ventral striatum in the cat: a behavioral and electrophysiological study.
AuthorsBouyer JJ, Montaron MF, Fabre-Thorpe M, Rougeul A
JournalExp Neurol
PubMed ID3709743
Bilateral lesions of the nucleus accumbens in cat elicited the following changes: preservation in tests requiring focused attention, with difficulty to shift to other targets; paucity of movements, animals displaying moderate hypokinesia and loss of reaction to changes in the environment. These symptoms were accompanied by a significant increase in ... More
Thermodynamic study on the effects of beta-cyclodextrin inclusion with anilinonaphthalenesulfonates.
AuthorsCatena GC, Bright FV
JournalAnal Chem
PubMed ID2719277
Thermodynamic parameters and stoichiometries for the binding of anilinonaphthalenesulfonates to beta-cyclodextrin are obtained from steady-state fluorescence intensity and anisotropy measurements. Specifically, formation constant, enthalpy, and entropy values are obtained for complexes of beta-cyclodextrin with eight different substrate molecules at five different temperatures and six different pH values, and their associated ... More
Fluorescence studies on the interaction between two cytochromes extracted from the yeast, Hansenula anomala.
AuthorsAlbani J
JournalArch Biochem Biophys
PubMed ID2998284
The binding of cytochrome c to the cytochrome b2 core, both extracted from the yeast, Hansenula anomala, has been studied. Cytochrome b2 core heme is extracted and replaced by the fluorescent probe, 2-p-toluidinylnaphthalene-6-sulfonate (TNS). A dissociation constant in the range of 85 microM is found for the TNS-apoprotein complex with ... More
Transbilayer transport of phosphatidic acid in response to transmembrane pH gradients.
AuthorsEastman SJ, Hope MJ, Cullis PR
JournalBiochemistry
PubMed ID1993189
Preliminary studies have shown that asymmetric transbilayer distributions of phosphatidic acid (PA) can be induced by transmembrane pH gradients (delta pH) in large unilamellar vesicles [Hope et al. (1989) Biochemistry 28, 4181-4187]. Here the mechanism of PA transport is examined employing TNS as a fluorescent probe of lipid asymmetry. It ... More
Novel N,N '-diacyl-1,3-diaminopropyl-2-carbamoyl bivalent cationic lipids for gene delivery--synthesis, in vitro transfection activity, and physicochemical characterization.
AuthorsSpelios M, Savva M,
JournalFEBS J
PubMed ID18067582
Novel N,N'-diacyl-1,3-diaminopropyl-2-carbamoyl bivalent cationic lipids were synthesized and their physicochemical properties in lamellar assemblies with and without plasmid DNA were evaluated to elucidate the structural requirements of these double-chained pH-sensitive surfactants for potent non-viral gene delivery and expression. The highest in vitro transfection efficacies were induced at +/-4:1 by the ... More
A fluorescence study of thermally induced conformational changes in yeast hexokinase.
AuthorsWasylewski Z, Criscimagna NL, Horowitz PM
JournalBiochim Biophys Acta
PubMed ID3899179
Fluorescence studies have been performed on yeast hexokinase (ATP: D-hexose 6-phosphotransferase, EC 2.7.1.1) as a function of temperature. Observations of both the intrinsic protein fluorescence and the fluorescence of the noncovalently bound apolar probe 2-(p-toluidinyl)naphthalene-6-sulfonic acid under conditions where hexokinase is monomeric, indicate that significant thermal structural transitions occur in ... More
Spectroscopic study on the effects of nonenzymatic glycation in human alpha-crystallin.
AuthorsLiang JN, Chylack LT
JournalInvest Ophthalmol Vis Sci
PubMed ID3570690
Nonenzymatic glycated lens alpha-crystallin, isolated from human diabetic cataract lenses, does not differ in subunit size and secondary structure from nonglycated alpha-crystallin. The tertiary structure, however, has undergone a significant change as reflected in the changes of near-ultraviolet (UV) circular dichroism (CD) and fluorescence of intrinsic probes (tryptophan, nontryptophan) and ... More
Tertiary structure of human alpha1-acid glycoprotein (orosomucoid). Straightforward fluorescence experiments revealing the presence of a binding pocket.
AuthorsAlbani JR
JournalCarbohydr Res
PubMed ID15013397
Binding of hemin to alpha1-acid glycoprotein has been investigated. Hemin binds to the hydrophobic pocket of hemoproteins. The fluorescent probe 2-(p-toluidino)-6-naphthalenesulfonate (TNS) binds to a hydrophobic domain in alpha1-acid glycoprotein with a dissociation constant equal to 60 microM. Addition of hemin to an alpha1-acid glycoprotein-TNS complex induces the displacement of ... More
Comparative effects of calmodulin inhibitors on calmodulin's hydrophobic sites and on the activation of cyclic nucleotide phosphodiesterase by calmodulin.
AuthorsSchaeffer P, Luginer C, Follenius-Wund A, Gerard D, Stoclet JC
JournalBiochem Pharmacol
PubMed ID3036157
Experiments were designed to investigate the effect of inhibitors on calmodulin's hydrophobic sites and their consequences on the activation of a target enzyme, cyclic nucleotide phosphodiesterase. Two fluorescent probes, 2-(p-toluidinyl)-naphthalene-6-sulfonate (TNS) and 9-anthroylcholine (9AC) were used to study the interactions with calmodulin of inhibitors devoid of direct effect on the ... More
Critical role of the linker region between helix D and strand 2A in heparin activation of antithrombin.
AuthorsMeagher JL, Olson ST, Gettins PG
JournalJ Biol Chem
PubMed ID10644732
The binding of pentasaccharide heparin to antithrombin induces a conformational change that is transmitted to the reactive center loop and increases the rate of inhibition of factor Xa by approximately 300-fold. The mechanism of such transmission is not known. To test the role of residues 134-137, which link helix D ... More
Interactions of lecithin and pig apolipoproteins of high density lipoproteins at the surface monolayer of reconstituted very small particles.
AuthorsHanda T, Komatsu H, Kakee A, Miyajima K
JournalChem Pharm Bull (Tokyo)
PubMed ID2279277
Cosonication of egg yolk lecithin and triolein with apolipoproteins isolated from pig high density lipoprotein (apoHDL) gave us reconstituted high density lipoprotein particles (r-HDLs) of 9 nm in average diameter. They were smaller than microemulsion particles (MEs) composed of the lipids (35 nm). The protein/egg yolk lecithin ratio in the ... More
Influence of the temperature in the adsorption of sodium dodecyl sulfate on phosphatidylcholine liposomes.
AuthorsCócera M, López O, Estelrich J, Parra JL, de la Maza A
JournalChem Phys Lipids
PubMed ID12787940
The influence of the temperature on the adsorption of monomeric and micellar solutions of the anionic surfactant sodium dodecyl sulfate (SDS) on phosphatidylcholine (PC) liposomes was investigated using the fluorescent probe 2-(p-toluidinyl)-naphthalene-6-sodium sulfonate (TNS). The number of adsorbed molecules was quantified by measuring changes in the electrostatic potential (Psi(o)) of ... More
4-Methylumbelliferyl-glycosides as fluorescence probes of sugar-binding sites on lectin molecules: spectral properties and dependence of fluorescence on polarity and viscosity.
AuthorsDecastel M, Vincent M, Matta KL, Frénoy JP
JournalArch Biochem Biophys
PubMed ID6465890
The spectral properties of 4-methylumbelliferyl-glycosides (MeUmb-glycosides) were investigated in order to assess their usefulness as probes of the microenvironment of sugar binding sites on lectin molecules. It was shown that the abnormally high values for fluorescence polarization of free MeUmb-glycosides (from 0.07 to 0.251) were due neither to their molecular ... More
Effects of myosin light chain kinase and peptides on Ca2+ exchange with the N- and C-terminal Ca2+ binding sites of calmodulin.
AuthorsJohnson JD, Snyder C, Walsh M, Flynn M
JournalJ Biol Chem
PubMed ID8557684
Myosin light chain kinase and peptides from the calmodulin (CaM) binding domains of myosin light chain kinase (RS-20, M-13), CaM kinase II, and the myristoylated alanine-rich protein kinase C substrate protein slowed Ca2+ dissociation from CaM's N-terminal sites from 405 +/- 75/s to 1.8-2.9/s and from CaM's C-terminal sites from ... More
Fluorescence analysis of hormone binding activities of wheat germ agglutinin.
Wheat germ agglutinin (WGA) from embryos of the monocotyledonous plant Triticum vulgaris (Graminaceae) is a carbohydrate binding protein characterized by high specificity to N-acetyl-d-glucosamine and N-acetyl-d-neuraminic acid. In this study we show that parallel to its carbohydrate binding activities, WGA binds with several orders of magnitude higher affinity adenine, adenine-related ... More
Influence of phospholipid asymmetry on fusion between large unilamellar vesicles.
AuthorsEastman SJ, Hope MJ, Wong KF, Cullis PR
JournalBiochemistry
PubMed ID1567871
The ability of lipid asymmetry to regulate Ca(2+)-stimulated fusion between large unilamellar vesicles has been investigated. It is shown that for 100-nm-diameter LUVs composed of dioleoylphosphatidylcholine, dioleoylphosphatidylethanolamine, phosphatidylinositol, and dioleoylphosphatidic acid (DOPC/DOPE/PI/DOPA; 25:60:5:10) rapid and essentially complete fusion is observed by fluorescent resonance energy transfer techniques when Ca2+ (8 mM) ... More
Fluorescence studies on the Ca2+ and Zn2+ binding properties of the alpha-subunit of bovine brain S-100a protein.
AuthorsLeung IK, Mani RS, Kay CM
JournalFEBS Lett
PubMed ID3569515
The single cysteine on the alpha-subunit of bovine brain S-100a protein has been modified with the thiol specific probe, Acrylodan. When the labelled apoprotein was excited at 380 nm the fluorescence emission maximum was centered at 484 +/- 2 nm, suggesting that the probe is in a fairly hydrophobic environment. ... More
Ion-enhanced fluorescence staining of sodium dodecyl sulfate-polyacrylamide gels using bis(8-p-toluidino-1-naphthalenesulfonate).
AuthorsHorowitz PM, Bowman S
JournalAnal Biochem
PubMed ID3425913
A method for the sensitive fluorescent staining of sodium dodecyl sulfate (SDS) gels that extends the applicability and sensitivity of existing procedures has been developed. SDS-protein complexes are able to bind the noncovalent hydrophobic probe, bis(8-p-toluidino-1-naphthalenesulfonate) (bisANS) with an increase in quantum yield that is considerably larger than that observed ... More
Influence of allosteric effectors on the kinetics and equilibrium binding of phosphoenolpyruvate (PEP) to phosphoenolpyruvate carboxylase (PEPC) from Zea mays.
AuthorsFrank J, Clarke RJ, Vater J, Holzwarth JF
JournalBiophys Chem
PubMed ID11527579
Phosphoenolpyruvate carboxylase (PEPC) the carbon dioxide processing enzyme of C(4) plants, shows the features of an allosteric enzyme. Allosteric activators such as D-glucose-6-phosphate and glycine increase the affinity of PEPC for its substrate PEP at pH 8.0 and pH 7.0. Allosteric inhibitors like L-malate and L-aspartate predominantly decrease the affinity ... More
Fluorescence study of the effects of aging and diabetes mellitus on human lens alpha-crystallin.
AuthorsLiang JN
JournalCurr Eye Res
PubMed ID3568749
Human alpha-crystallins were separated from fetal, young, senile nondiabetic and diabetic lenses. The effects of aging and diabetes mellitus were studied by fluorescence measurements, including emission maximum, quantum yield and polarization, using both intrinsic probes (tryptophan and non-tryptophan) and extrinsic probes [4-(N-iodoacetoxy)N-methylamino-7-nitrobenz-2-oxa-1,3-diazole (IANBD) and 6-(p-toluidinyl)naphthalene-2-sulfonate (TNS)]. Results indicate that diabetic ... More
Modulation of membrane fusion by asymmetric transbilayer distributions of amino lipids.
AuthorsBailey AL, Cullis PR
JournalBiochemistry
PubMed ID7918482
The fusion of model lipid bilayers containing synthetic amino lipids and the regulation of this fusion by inducing transbilayer asymmetry of these amino lipids via imposed pH gradients are demonstrated. Liposomes of 100 nm diameter consisting of 5 mol% 1,2-dioleoyl-3-(N,N-dimethylamino)propane (AL1) in a mixture of egg phosphatidylcholine (EPC), dioleoylphosphatidylethanolamine (DOPE), ... More
Structure of native protein C inhibitor provides insight into its multiple functions.
AuthorsLi W, Adams TE, Kjellberg M, Stenflo J, Huntington JA
JournalJ Biol Chem
PubMed ID17337440
Protein C inhibitor (PCI) is a multifunctional serpin with wide ranging protease inhibitory functions, unique cofactor binding activities, and potential non-inhibitory functions akin to the hormone-transporting serpins. To gain insight into the molecular mechanisms utilized by PCI we developed a robust expression system in Escherichia coli and solved the crystal ... More
pH-enhanced cytopathic effects of Clostridium sordellii lethal toxin.
AuthorsQa'Dan M, Spyres LM, Ballard JD
JournalInfect Immun
PubMed ID11500421
Clostridium sordellii lethal toxin (TcsL) is a large clostridial toxin (LCT) that glucosylates Ras, Rac, and Ral. TcsL differs from other LCTs because it modifies Ras, which does not cycle from cytosol to membrane. By using a suite of inhibitors, steps in cell entry by TcsL were dissected, and entry ... More
pH-induced conformational changes in Clostridium difficile toxin B.
AuthorsQa'Dan M, Spyres LM, Ballard JD
JournalInfect Immun
PubMed ID10768933
Toxin B from Clostridium difficile is a monoglucosylating toxin that targets substrates within the cytosol of mammalian cells. In this study, we investigated the impact of acidic pH on cytosolic entry and structural changes within toxin B. Bafilomycin A1 was used to block endosomal acidification and subsequent toxin B translocation. ... More
Interactions of voltage-sensing dyes with membranes. III. Electrical properties induced by merocyanine 540.
AuthorsKrasne S
JournalBiophys J
PubMed ID6661489
The effects of merocyanine 540 on the electrical properties of lipid bilayer membranes have been investigated. The alterations this dye was found to produce in the intrinsic conductances of these membranes were minimal, but it profoundly altered the conductances produced by extrinsic permeant species. These alterations were much larger for ... More
Spectral properties of environmentally sensitive probes associated with horseradish peroxidase.
AuthorsLasagna M, Vargas V, Jameson DM, Brunet JE
JournalBiochemistry
PubMed ID8547280
The environmentally sensitive fluorescent probes 6-propionyl-2-(N,N-dimethylamino)naphthalene (PRODAN) and 2'-(N,N-dimethylamino)-6-naphthoyl-4-trans-cyclohexanioc acid (DANCA) form complexes with the heme binding site of apohorseradish peroxidase. The dissociation constants of the PRODAN and DANCA complexes were determined from anisotropy titration data to be approximately 8.7 x 10(-5) and 3.3 x 10(-4) M, respectively. From comparison ... More
Acidic pH modulates the interaction between human granulocyte-macrophage colony-stimulating factor and glycosaminoglycans.
AuthorsWettreich A, Sebollela A, Carvalho MA, Azevedo SP, Borojevic R, Ferreira ST, Coelho-Sampaio T
JournalJ Biol Chem
PubMed ID10531349
Granulocyte-macrophage colony-stimulating factor (GM-CSF) controls growth and differentiation of hematopoietic cells. Previous reports have indicated that the mitogenic activity of GM-CSF may be modulated by the glycosidic moiety of proteoglycans associated with the membrane of stromal cells. In this work, we have performed in vitro studies of the interaction between ... More
Studies on the irreversible step of pepsinogen activation.
AuthorsGlick DM, Shalitin Y, Hilt CR
JournalBiochemistry
PubMed ID2730880
The bond cleavage step of pepsinogen activation has been investigated in a kinetic study in which the denatured products of short-term acidifications were separated on SDS-polyacrylamide gels and the peptide products were quantitated by densitometry. Although several peptide products were observed, under the conditions of the experiments (pH values between ... More
Acid-induced dissociation of alpha A- and alpha B-crystallin homopolymers.
AuthorsStevens A, Augusteyn RC
JournalBiophys J
PubMed ID8274652
Homopolymers were constructed from the alpha A and alpha B polypeptides isolated from the lens protein alpha-crystallin. As the pH is lowered from 7.0 to 3.4, these homopolymers dissociate to smaller species with molecular masses ranging from 80 to 250 kDa for the alpha A and around 140 kDa for ... More
Divalent cations can induce the exposure of GroEL hydrophobic surfaces and strengthen GroEL hydrophobic binding interactions. Novel effects of Zn2+ GroEL interactions.
AuthorsBrazil BT, Ybarra J, Horowitz PM
JournalJ Biol Chem
PubMed ID9452440
Fluorescent and non-fluorescent probes have been used to show that divalent cations (Ca2+, Mg2+, Mn2+, and Zn2+) significantly increase hydrophobic exposure on GroEL, whereas monovalent cations (K+ and Na+) have little effect. Zn2+ always induced the largest amount of hydrophobic exposure on GroEL. By using a new method based on ... More
Monitoring of chemical and enzymatic hydrolysis of water-soluble proteins using flow-injection analysis with fluorescence detection and an aqueous eluant containing 2-p-toluidinylnaphthalene-6-sulfonate as the fluorescent probe.
AuthorsSentandreu E, Carbonell JV, Sendra JM
JournalBiotechnol Bioeng
PubMed ID12001176
The exposed hydrophobicity of proteins, which is due to the hydrophobic regions located on their surfaces, enhances the fluorescence intensity of the probe 2-p-toluidinylnaphthalene-6-sulfonate (2,6-TNS) by the formation of a complex. During the hydrolysis of a protein, the average exposed hydrophobicity of the substrate continuously changes with incubation time, and ... More
Interaction of the isolated transmembrane domain of diphtheria toxin with membranes.
Insertion of diphtheria toxin's T (transmembrane) domain into the endosomal membrane under acidic conditions is known to promote translocation of its catalytic domain across the membrane and into the cytosol. The T domain, a cysteine-free bundle of alpha-helices, was expressed as a discrete protein in Escherichia coli and purified. The ... More
Sequence-specific DNA displaces 6-p-toluidino-2-naphthalenesulfonate bound to a hydrophobic site on the DNA-binding domain of Drosophila c-myb.
AuthorsMadan A, Hosur RV, Padhy LC
JournalBiochemistry
PubMed ID8003478
The N-terminal DNA-binding domain of c-myb oncoprotein binds to DNA in a sequence-specific manner. The domain, consisting of three imperfect tandem repeats, has tryptophan residues at very regular intervals and this is believed to be of some significance in the DNA-binding activity of the protein. We have found that the ... More
Determination of beta-amylase activity by a fluorimetric 2-p-toluidinylnaphthalene-6-sulfonate flow-injection analysis (2, 6-TNS-FIA) method, using amylose and amylopectin as substrates.
AuthorsBatlle N, Carbonell JV, Sendra JM
JournalBiotechnol Bioeng
PubMed ID10592509
2-p-Toluidinylnaphthalene-6-sulfonate (2,6-TNS) is a compound which is barely fluorescent in pure water but whose fluorescence can be strongly enhanced if the environment becomes hydrophobic, i.e. by the addition of suitable substrates such as proteins or 1, 4-alpha-D-glucans. The enhancement of fluorescence results from the formation of a 2,6-TNS/substrate complex. For ... More
Influence of transbilayer area asymmetry on the morphology of large unilamellar vesicles.
The morphological consequences of differences in the monolayer surface areas of large unilamellar vesicles (LUVs) have been examined employing cryoelectron microscopy techniques. Surface area was varied by inducing net transbilayer transport of dioleoylphosphatidylglycerol (DOPG) in dioleoylphosphatidylcholine (DOPC):DOPG (9:1, mol:mol) LUVs in response to transmembrane pH gradients. It is shown that ... More
Specialized functional domains in hemoglobin: dimensions in solution of the apohemoglobin dimer labeled with fluorescein iodoacetamide.
AuthorsSassaroli M, Bucci E, Liesegang J, Fronticelli C, Steiner RF
JournalBiochemistry
PubMed ID6548152
The fluorescence characteristics of 8-anilino-naphthalene-1-sulfonic acid (ANS) coupled to apohemoglobin and to apohemoglobin labeled with fluorescein iodoacetamide (FIA) at beta-93 have been compared. The quenching of emission of ANS produced by FIA was measured both with steady-state and with time-resolved techniques. In this system the emission of ANS in the ... More
Poly(ethylene glycol)-modification of the phospholipid vesicles by using the spontaneous incorporation of poly(ethylene glycol)-lipid into the vesicles.
AuthorsSou K, Endo T, Takeoka S, Tsuchida E
JournalBioconjug Chem
PubMed ID10821653
The critical micelle concentrations of 1, 2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-[monomethoxy poly(ethylene glycol) (5000)] (PEG-DPPE) and its distearoyl analogue (PEG-DSPE) were 70 and 9 microM, respectively, in buffer solutions ([Tris] = 20 mM, [NaCl] = 140 mM, pH 7.4) at 37 degrees C. When these PEG-lipid micelle dispersions were mixed with the dispersions of ... More
Reaction of proteinases with alpha 2-macroglobulin: rapid-kinetic evidence for a conformational rearrangement of the initial alpha 2-macroglobulin-trypsin complex.
AuthorsStrickland DK, Larsson LJ, Neuenschwander DE, Björk I
JournalBiochemistry
PubMed ID1706626
The kinetics of the reaction of trypsin with alpha 2M were examined under pseudo-first-order conditions with excess inhibitor. Initial studies indicated that the fluorescent dye TNS is a suitable probe for monitoring the reaction over a wide concentration range of reactants. Titration experiments showed that the conformational changes associated with ... More
Effects of structure of polyamidoamine dendrimer on gene transfer efficiency of the dendrimer conjugate with alpha-cyclodextrin.
AuthorsKihara F, Arima H, Tsutsumi T, Hirayama F, Uekama K
JournalBioconjug Chem
PubMed ID12440855
To improve gene transfer activity of a new nonviral vector, a polyamidoamine dendrimer (G2) conjugate with alpha-cyclodextrin (alpha-CDE conjugate (G2)), we prepared alpha-CDE conjugates with dendrimer having different generations (G3 and G4), and their gene transfer activities were compared with those of alpha-CDE conjugate (G2) and TransFast, a novel transfection ... More
Thiol ester cleavage-dependent conformational change in human alpha 2-macroglobulin. Influence of attacking nucleophile and of Cys949 modification.
AuthorsGettins PG
JournalBiochemistry
PubMed ID7547965
Cleavage of the thiol ester that exists between the side chains of Cys949 and Gln952 in human alpha 2-macroglobulin (alpha 2M) destabilizes the native conformation and leads to a large-scale conformational change that results in exposure of the receptor binding domain and to changes in electrophoretic mobility and sedimentation coefficient. ... More
Bridged bis(beta-cyclodextrin)s possessing coordinated metal center(s) and their inclusion complexation behavior with model substrates: enhanced molecular binding ability by multiple recognition.
AuthorsLiu Y, Chen Y, Li L, Zhang HY, Liu SX, Guan XD
JournalJ Org Chem
PubMed ID11735533
To investigate quantitatively the cooperative binding ability of several beta-cyclodextrin oligomers bearing single or multiligated metal center(s), the inclusion complexation behavior of four bis(beta-cyclodextrin)s (2-5) linked by 2,2'-bipyridine-4,4'-dicarboxy tethers and their copper(II) complexes (6-9) with representative dye guests, i.e., methyl orange (MO), acridine red (AR), rhodamine B (RhB), ammonium 8-anilino-1-naphthalenesulfonic ... More
Analysis of calcium-dependent interaction between amino-terminal conserved region of calpastatin functional domain and calmodulin-like domain of mu-calpain large subunit.
AuthorsYang HQ, Ma H, Takano E, Hatanaka M, Maki M
JournalJ Biol Chem
PubMed ID8034655
Calpain requires Ca2+ both for proteolysis of its substrates and for interaction with its endogenous inhibitor, calpastatin. Although calmodulin-like domains (CaMLDs) of large and small subunits of calpain have been suggested to be the sites for Ca(2+)-dependent interaction with calpastatin, specificity and molecular basis of the interaction have remained unclear. ... More
Myelin basic protein binds heme at a specific site near the tryptophan residue.
Fluorescence of the single tryptophan residue in myelin basic protein (MBP) was excited directly at 295 nm (red-edge excitation) or at 278 nm which allows, in addition, indirect excitation by resonance energy transfer (RET) from any nearby tyrosine residues. Both red-edge excitation and the RET pathway were collisionally quenched by ... More
Cooperative molecular recognition of dyes by dyad and triad cyclodextrin-crown ether conjugates.
AuthorsLiu Y, Yang YW, Li L, Chen Y
JournalOrg Biomol Chem
PubMed ID15136812
Three beta-cyclodextrin (beta-CyD) derivatives with crown ether units, that is N-(4'-benzo-15-crown-5)-6-imino-6-deoxy-beta-CyD (2), 6,6'-[N-(4,4'-dibenzo-18-crown-6)-imino]-bridged bis(beta-CyD)(3), and 2,2'-[O-(4',5'-benzo-15-crown-5)-ethyl]-bridged bis (beta-CyD)(5), were synthesized as cooperative recognition receptor models. Their molecular binding behavior with four representative fluorescent dyes, i.e., ammonium 8-anilino-1-naphthalenesulfonate (ANS), sodium-6-toluidino-2-naphthalene-sulfonate (TNS), Acridine Red (AR) and Rhodamine B (RhB), was investigated in ... More
Fluorophore environments in membrane-bound probes: a red edge excitation shift study.
AuthorsChattopadhyay A, Mukherjee S
JournalBiochemistry
PubMed ID8466919
A shift in the wavelength of maximum fluorescence emission toward higher wavelengths, caused by a shift in the excitation wavelength toward the red edge of the absorption band, is termed the Red Edge Excitation Shift (REES). This effect is mostly observed with polar fluorophores in motionally restricted media such as ... More
Alpha 2-macroglobulin bait region variants. A role for the bait region in tetramer formation.
AuthorsGettins PG, Hahn KH, Crews BC
JournalJ Biol Chem
PubMed ID7539801
To test the hypothesis that a large portion of the bait region of human alpha 2-macroglobulin (alpha 2M) can be removed without adversely affecting the protein's structural and functional properties, we expressed two human alpha 2M variants with truncated bait regions and examined whether these variants folded normally and functioned ... More
Calmodulin-dependent enzymes undergo a protein-induced conformational change that is associated with their interactions with calmodulin.
AuthorsHuang S, Carlson GM, Cheung WY
JournalJ Biol Chem
PubMed ID8125988
The anionic hydrophobic (amphipathic) fluorescent probe 2-(p-toluidinyl)-naphthalene-6-sulfonate was used to investigate the surface hydrophobic properties of calmodulin (CaM)-dependent enzymes as follows: calcineurin, myosin light chain kinase, cyclic nucleotide phosphodiesterase, CaM-dependent protein kinase II, and the gamma-subunit of phosphorylase kinase. We found that certain domains of these enzymes that interacted with ... More
Synthesis of novel bis(beta-cyclodextrin)s and metallobridged bis(beta-cyclodextrin)s with 2,2'-diselenobis(benzoyl) tethers and their molecular multiple recognition with model substrates.
AuthorsLiu Y, Li L, Zhang HY, Song Y
JournalJ Org Chem
PubMed ID12530880
To investigate quantitatively the cooperative binding ability of beta-cyclodextrin dimers, a series of bridged bis(beta-cyclodextrin)s with 2,2'-diselenobis(benzoyl) spacer connected by different lengths of oligo(ethylenediamine)s (2-5) and their platinum(IV) complexes (6-9) have been synthesized and their inclusion complexation behavior with selected substrates, such as Acridine Red, Neutral Red, Brilliant Green, Rhodamine ... More
Reactions of fluorescent probes with normal and chemically modified myelin basic protein and proteolipid. Comparisons with myelin.
AuthorsFeinstein MB, Felsenfeld H
JournalBiochemistry
PubMed ID50085
Basic (encephalitogenic) protein and water-soluble proteolipid apoprotein isolated from bovine brain myelin bind 8-anilino-1-naphthalenesulfonate and 2-p-toluidinylnaphthalene-6-sulfonate with resulting enhancement of dye fluorescence and a blue-shift of the emission spectrum. The dyes had a higher affinity and quantum yield, when bound to the proteolipid (Kans=2.3x10--6,=0.67) than to the basic protein (Kans=3.3x10--5,=0.40). ... More
Structural influence of cation binding to recombinant human brain S100b: evidence for calcium-induced exposure of a hydrophobic surface.
AuthorsSmith SP, Barber KR, Dunn SD, Shaw GS
JournalBiochemistry
PubMed ID8688416
The dimeric calcium-binding protein S100b is proposed to undergo a calcium-induced structural change allowing it to interact, via a hydrophobic surface, with other proteins. Previously it has been suggested that calcium binding to S100b leads to the exposure of at least one phenylalanine residue (Mani et al., 1982, 1983). This ... More
Conformational studies of aqueous melittin. Characteristics of a fluorescent probe binding site.
AuthorsCondie CC, Quay SC
JournalJ Biol Chem
PubMed ID6863287
The structural basis of the interaction of melittin with amphipathic molecular assemblies, i.e. membranes, was investigated by studying the binding of 2-p-toluidinylnaphthalene-6-sulfonate (TNS) to melittin by ultraviolet and fluorescence spectroscopy. Monomeric melittin did not significantly bind TNS as judged by UV and fluorescent spectroscopy. Tetrameric melittin bound two TNS molecules ... More
Interfacial properties of model membranes and plasma lipoproteins containing ether lipids.
AuthorsMassey JB, She HS, Pownall HJ
JournalBiochemistry
PubMed ID4074734
The interfacial properties of synthetic ester and ether phosphatidylcholines (PCs) were investigated by using the polarity-sensitive fluorescent probes 6-propionyl-2-(dimethylamino)naphthalene (Prodan) and pyrene. The physical state of the phospholipid matrix was determined by fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH). Single-bilayer phospholipid vesicles formed by sonication and model high-density lipoproteins were studied. On ... More
Effect of site-directed mutagenesis of methylglyoxal-modifiable arginine residues on the structure and chaperone function of human alphaA-crystallin.
AuthorsBiswas A, Miller A, Oya-Ito T, Santhoshkumar P, Bhat M, Nagaraj RH
JournalBiochemistry
PubMed ID16584192
We reported previously that chemical modification of human alphaA-crystallin by a metabolic dicarbonyl compound, methylglyoxal (MGO), enhances its chaperone-like function, a phenomenon which we attributed to formation of argpyrimidine at arginine residues (R) 21, 49, and 103. This structural change removes the positive charge on the arginine residues. To explore ... More
Paradoxical effects of substitution and deletion mutation of Arg56 on the structure and chaperone function of human alphaB-crystallin.
AuthorsBiswas A, Goshe J, Miller A, Santhoshkumar P, Luckey C, Bhat MB, Nagaraj RH
JournalBiochemistry
PubMed ID17260942
Human alphaB-crystallin is a small heat-shock protein that functions as a molecular chaperone. Recent studies indicate that deletion of a peptide (54FLRAPSWF61) from its N-terminus makes it a better chaperone, and this particular sequence is thought to participate in substrate interaction and subunit exchange with alphaA-crystallin. To determine whether the ... More
Critical role of asparagine 1065 of human alpha2-macroglobulin in formation and reactivity of the thiol ester.
AuthorsSuda SA, Dolmer K, Gettins PG
JournalJ Biol Chem
PubMed ID9388263
It has been shown that the relative reaction preference of the C4 thiol ester toward oxygen and nitrogen nucleophiles upon activation by proteinase depends on whether residue 1106 is aspartate or histidine (Dodds, A. W., Ren, X.-D., Willis, A. C., and Law, S. K. A. (1996) Nature 379, 177-179). To ... More