Interaction of 1,1'-bi(4-anilino)naphthalene-5,5'-disulfonic acid with alpha-crystallin.
AuthorsSharma KK, Kaur H, Kumar GS, Kester K
JournalJ Biol Chem
PubMed ID9535881
'The hydrophobic sites in alpha-crystallin were evaluated using a fluorescent probe 1,1''-bi(4-anilino)naphthalenesulfonic acid (bis-ANS). Approximately one binding site/subunit of alpha-crystallin at 25 degrees C was estimated by equilibrium binding and Scatchard analysis (Kd = 1.1 microM). Based on fluorescence titration, the dissociation constant was 0.95 microM. The number of bis-ANS ... More
Plurality of protein conformations of ribulose-1,5-bisphosphate carboxylase/oxygenase monomers probed by high pressure electrophoresis.
AuthorsErijman L, Paladini AA, Lorimer GH, Weber G
JournalJ Biol Chem
PubMed ID7902356
'We used hydrostatic pressure in the range of 1 to 2 kbar, coupled with polyacrylamide gel electrophoresis, to investigate the properties of monomers of dimeric ribulose bisphosphate carboxylase/oxygenase. At temperatures below -5 degrees C or pressures above 1.5 kbar, only a diffuse band with low electrophoretic mobility was observed, which ... More
An operator-induced conformational change in the C-terminal domain of the lambda repressor.
AuthorsSaha R, Banik U, Bandopadhyay S, Mandal NC, Bhattacharyya B, Roy S
JournalJ Biol Chem
PubMed ID1532575
'4,4''-bis(1-anilino-8-naphthalenesulfonic acid (Bis-ANS), an environment-sensitive fluorescent probe for hydrophobic region of proteins, binds specifically to the C-terminal domain of lambda repressor. The binding is characterized by positive cooperativity, the magnitude of which is dependent on protein concentration in the concentration range where dimeric repressor aggregates to a tetramer. In this ... More
Exploiting new potential targets for anti-hepatitis B virus drugs.
AuthorsWen YM, Lin X, Ma ZM
JournalCurr Drug Targets Infect Disord
PubMed ID14529356
'Based on the recent studies of HBV strains with different replication efficiency, several new potential targets for anti-HBV replication have been presented. These include the viral and cellular regulatory factors associated with HBV replication and the process for encapsidation of viral genome and budding into endoplasmic reticulum (ER). A putative ... More
Detection of disulfide bonds in bovine brain tubulin and their role in protein folding and microtubule assembly in vitro: a novel disulfide detection approach.
AuthorsChaudhuri AR, Khan IA, Ludueña RF
JournalBiochemistry
PubMed ID11467944
'Cysteine residues in tubulin are actively involved in regulating ligand interactions and microtubule formation both in vivo and in vitro. These cysteine residues are sensitive reporters in determining the conformation of tubulin. Although some of the cysteines are critical in modulating drug binding and microtubule assembly, it is not clear ... More
Cooperative multiple binding of bisANS and daunomycin to tubulin.
AuthorsWard LD, Timasheff SN
JournalBiochemistry
PubMed ID7918408
'The binding of daunomycin and bisANS to tubulin was studied by direct equilibrium techniques. Both ligands generated abnormal Scatchard plots. Their concave-downward nature indicated positive cooperativity. The data conform to tubulin possessing ca. 35 daunomycin binding sites with a binding constant of 570-1430 M-1. The binding of bisANS is characterized ... More
Gap junctional communication in the early Xenopus embryo.
AuthorsLandesman Y, Goodenough DA, Paul DL
JournalJ Cell Biol
PubMed ID10953017
'In the Xenopus embryo, blastomeres are joined by gap junctions that allow the movement of small molecules between neighboring cells. Previous studies using Lucifer yellow (LY) have reported asymmetries in the patterns of junctional communication suggesting involvement in dorso-ventral patterning. To explore that relationship, we systematically compared the transfer of ... More
Folding intermediates of the prion protein stabilized by hydrostatic pressure and low temperature.
AuthorsMartins SM, Chapeaurouge A, Ferreira ST
JournalJ Biol Chem
PubMed ID14525996
'Prion diseases are associated with conformational conversion of the cellular prion protein, PrPC, into a misfolded form, PrPSc. We have investigated the equilibrium unfolding of the structured domain of recombinant murine prion protein, comprising residues 121-231 (mPrP-(121-231)). The equilibrium unfolding of mPrP-(121-231) by urea monitored by intrinsic fluorescence and circular ... More
Intrinsically disordered structure of Bacillus pasteurii UreG as revealed by steady-state and time-resolved fluorescence spectroscopy.
AuthorsNeyroz P, Zambelli B, Ciurli S
JournalBiochemistry
PubMed ID16846235
'UreG is an essential protein for the in vivo activation of urease. In a previous study, UreG from Bacillus pasteurii was shown to behave as an intrinsically unstructured dimeric protein. Here, intrinsic and extrinsic fluorescence experiments were performed, in the absence and presence of denaturant, to provide information about the ... More
Detection of conformational changes in chloroplast coupling factor 1 by 8-anilino-1-naphthalene-sulphonate fluorescence changes.
AuthorsPick U, Finel M
JournalEur J Biochem
PubMed ID6225641
'Chloroplast coupling factor 1 (CF1) contains a high-affinity binding site for 8-anilino-1-napthalene sulphonate (ANS,Kd = 5-6 microM). The binding of ANS to the enzyme is associated with a fluorescence enhancement and a blue-shift in the emission spectrum. ANS only slightly inhibits ATP hydrolysis by CF1. Adenine nucleotides and inorganic phosphate ... More
Probing the unfolding pathway of alpha1-antitrypsin.
AuthorsJames EL, Whisstock JC, Gore MG, Bottomley SP
JournalJ Biol Chem
PubMed ID10092631
'Protein misfolding plays a role in the pathogenesis of many diseases. alpha1-Antitrypsin misfolding leads to the accumulation of long chain polymers within the hepatocyte, reducing its plasma concentration and predisposing the patient to emphysema and liver disease. In order to understand the misfolding process, it is necessary to examine the ... More
Exposed hydrophobic sites in factor VIII and isolated subunits.
AuthorsSudhakar K, Fay PJ
JournalJ Biol Chem
PubMed ID8798489
'Hydrophobic sites on the surface of factor VIII, factor VIIIa, and their derived subunits were evaluated using the fluorescent, apolar probe, bisanilinonapthalsulfonic acid (bis-ANS). Two hydrophobic sites, with indicated affinities for the probe, were identified on factor VIII (Kd = 0.2 and 1.22 microM), the isolated heavy chain (HC; Kd ... More
Probing of DNA-binding sites of Escherichia coli RecA protein utilizing 1-anilinonaphthalene-8-sulfonic acid.
AuthorsMasui R, Kuramitsu S
JournalBiochemistry
PubMed ID9724525
'RecA protein of Escherichia coli plays an essential role in homologous recombination of DNA strands. To analyze the interaction of RecA with single-stranded DNA (ssDNA), we performed a fluorescence competition assay employing 1-anilinonaphthalene-8-sulfonic acid (ANS) as an extrinsic fluorescent probe. ANS bound to RecA at three sites, leading to enhancement ... More
Glycerol-assisted restorative adjustment of flavoenzyme conformation perturbed by site-directed mutagenesis.
AuthorsRaibekas AA, Massey V
JournalJ Biol Chem
PubMed ID9268372
'The replacement of histidine 307 with leucine in pig kidney D-amino acid oxidase perturbs its active site conformation accompanied by dramatic losses in protein-flavin interactions and enzymatic activity. However, the negative effect of this mutation on the holoenzyme structure is essentially eliminated in the presence of glycerol, resulting in up ... More
A mathematical model of the kinetics of beta-amyloid fibril growth from the denatured state.
AuthorsPallitto MM, Murphy RM
JournalBiophys J
PubMed ID11509390
'Spontaneous conversion of beta-amyloid peptide (Abeta) from soluble monomer to insoluble fibril may underlie the neurodegeneration associated with Alzheimer''s disease. A complete description of Abeta self-association kinetics requires identification of the oligomeric species present and the pathway of association, as well as quantitation of rate constants and reaction order. Abeta ... More
Aluminum fluoride interactions with troponin C.
AuthorsPhan BC, Reisler E
JournalBiophys J
PubMed ID8312488
'The increasing interest in the metal ion aluminum fluoride and beryllium fluoride complexes as phosphate analogs in the myosin ATPase reaction and in muscle fiber studies prompted the examination of their interactions with the regulatory system of troponin and tropomyosin. In this work, the effects of these metal ion analogs ... More
IKP104-induced decay of tubulin: role of the A-ring binding site of colchicine.
'Tubulin, the major subunit protein of microtubules, has a tendency to lose its ability to assemble or to interact with ligands in a time-dependent process known as decay. Decay involves the increase in exposure of sulfhydryl groups and hydrophobic areas. The antimitotic drug IKP104 [2-(4-fluorophenyl)-1-(2-chloro-3, 5-dimethoxyphenyl)-3-methyl-6-phenyl-4(1H)-pyridinone] accelerates the decay of ... More
Temperature-induced conformational switch in intestinal fatty acid binding protein (IFABP) revealing an alternative mode for ligand binding.
AuthorsArighi CN, Rossi JP, Delfino JM
JournalBiochemistry
PubMed ID12809510
'IFABP is a small beta-barrel protein with a short helix-turn-helix motif near the N-terminus that is thought to participate in the regulation of the uptake and delivery of fatty acids. In a previous work, we detected by near UV circular dichroism a reversible conformational transition of this protein occurring between ... More
Protein stability induced by ligand binding correlates with changes in protein flexibility.
AuthorsCelej MS, Montich GG, Fidelio GD
JournalProtein Sci
PubMed ID12824495
'The interaction between ligands and proteins usually induces changes in protein thermal stability with modifications in the midpoint denaturation temperature, enthalpy of unfolding, and heat capacity. These modifications are due to the coupling of unfolding with binding equilibrium. Furthermore, they can be attained by changes in protein structure and conformational ... More
Recoverin is a zinc-binding protein.
AuthorsPermyakov SE, Cherskaya AM, Wasserman LA, Khokhlova TI, Senin II, Zargarov AA, Zinchenko DV, Zernii EY, Lipkin VM, Philippov PP, Uversky VN, Permyakov EA
JournalJ Proteome Res
PubMed ID12643543
'Recoverin is an N-myristoylated 23 kDa calcium-binding protein from retina, which modulates the Ca2+-sensitive deactivation of rhodopsin via Ca2+-dependent inhibition of rhodopsin kinase. It was shown by intrinsic and bis-ANS probe fluorescence, circular dichroism, and differential scanning calorimetry that myristoylated recombinant recoverin interacts specifically with zinc ions. Similar to the ... More
Mapping fatty acid binding to beta-lactoglobulin: Ligand binding is restricted by modification of Cys 121.
AuthorsNarayan M, Berliner LJ
JournalProtein Sci
PubMed ID9514270
'Native beta-lactoglobulin (Blg) binds 1 mole of palmitic acid per mole of protein with a dissociation constant of 0.6 microM for the primary fatty acid binding site. Chemical modification of Cys 121, which lies at the external putative hydrophobic binding site of Blg, does not affect retinol or 4,4''-bis 1-(phenylamino)-8-naphthalenesulfonate ... 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
Partially folded states of the capsid protein of cowpea severe mosaic virus in the disassembly pathway.
AuthorsGaspar LP, Johnson JE, Silva JL, Da Poian AT
JournalJ Mol Biol
PubMed ID9344752
'The different partially folded states of the capsid protein that appear in the disassembly pathway of cowpea severe mosaic virus (CPSMV) were investigated by examining the effects of hydrostatic pressure, sub-zero temperatures and urea. The conformational states of the coat protein were analyzed by their intrinsic fluorescence, binding of bis(8-anilinonaphthalene-1-sulfonate) ... More
Conformational properties of substrate proteins bound to a molecular chaperone alpha-crystallin.
AuthorsDas KP, Petrash JM, Surewicz WK
JournalJ Biol Chem
PubMed ID8631839
'alpha-Crystallin, the major protein of the ocular lens, acts as a molecular chaperone by suppressing the nonspecific aggregation of damaged proteins. To investigate the mechanism of the interaction between alpha-crystallin and substrate proteins, we prepared a tryptophan-free mutant of human alpha A-crystallin and assessed the conformation of thermally destabilized proteins ... More
Temperature-dependent chaperone activity and structural properties of human alphaA- and alphaB-crystallins.
AuthorsReddy GB, Das KP, Petrash JM, Surewicz WK
JournalJ Biol Chem
PubMed ID10671481
'The chaperone activity and biophysical properties of recombinant human alphaA- and alphaB-crystallins were studied by light scattering and spectroscopic methods. While the chaperone function of alphaA-crystallin markedly improves with an increase in temperature, the activity of alphaB homopolymer appears to change very little upon heating. Compared with alphaB-crystallin, the alphaA-homopolymer ... More
Identification of 1,1'-bi(4-anilino)naphthalene-5,5'-disulfonic acid binding sequences in alpha-crystallin.
AuthorsSharma KK, Kumar GS, Murphy AS, Kester K
JournalJ Biol Chem
PubMed ID9624133
'The hydrophobic binding sites in alpha-crystallin were evaluated using fluorescent probes 1,1''-bi(4-anilino)naphthalenesulfonic acid (bis-ANS), 8-anilino-1-naphthalene sulfonate (ANS), and 1-azidonaphthalene 5-sulfonate (1,5-AZNS). The photolysis of bis-ANS-alpha-crystallin complex resulted in incorporation of the probe to both alphaA- and alphaB-subunits. Prior binding of denatured alcohol dehydrogenase to alpha-crystallin significantly decreased the photoincorporation of ... More
Proteinaceous infectious behavior in non-pathogenic proteins is controlled by molecular chaperones.
AuthorsBen-Zvi AP, Goloubinoff P
JournalJ Biol Chem
PubMed ID12377766
'External stresses or mutations may cause labile proteins to lose their distinct native conformations and seek alternatively stable aggregated forms. Molecular chaperones that specifically act on protein aggregates were used here as a tool to address the biochemical nature of stable homo- and hetero-aggregates from non-pathogenic proteins formed by heat-stress. ... More
Human alpha-fetoprotein as a Zn(2+)-binding protein. Tight cation binding is not accompanied by global changes in protein structure and stability.
AuthorsPermyakov SE, Oberg KA, Cherskaya AM, Shavlovsky MM, Permyakov EA, Uversky VN
JournalBiochim Biophys Acta
PubMed ID11781144
'The binding of zinc to human alpha-fetoprotein (AFP) isolated from human umbilical cord serum was studied by fluorimetric Zn(2+)-titration. We found that the total number of strong binding sites for zinc on this protein was 5: AFP has one very strong (dissociation constant, K(d)<10(-8) M) and at least four lower ... More
Exposure of hydrophobic surfaces on the chaperonin GroEL oligomer by protonation or modification of His-401.
AuthorsGibbons DL, Horowitz PM
JournalJ Biol Chem
PubMed ID7706275
'Hydrophobic exposure on the chaperonin GroEL is increased 6-10-fold after the protein is treated with the His-reactive reagent diethyl pyrocarbonate (DEP), or the solution pH is lowered to 5.5. The induced hydrophobic surfaces have the same 1,1''-bis(4-anilino)naphthalene-5,5''-disulfonic acid (bis-ANS) binding characteristics as unperturbed GroEL: a Kd approximately equal to 3.5 ... More
Aggregation, dissociation and unfolding of glucose dehydrogenase during urea denaturation.
AuthorsMendoza-Hernández G, Minauro F, Rendón JL
JournalBiochim Biophys Acta
PubMed ID10825533
'The effect of urea on glucose dehydrogenase from Bacillus megaterium has been studied by following changes in enzymatic activity, conformation and state of aggregation. It was found that the denaturation process involves several transitions. At very low urea concentrations (below 0.5 M), where the enzyme is fully active and tetrameric, ... More
Supramolecular ligands: monomer structure and protein ligation capability.
AuthorsStopa B, Górny M, Konieczny L, Piekarska B, Rybarska J, Skowronek M, Roterman I
JournalBiochimie
PubMed ID9924974
'The aim of this work was to define the chemical structure of compounds self-assembling in water solutions, which appear to interact with proteins as single ligands with their supramolecular nature preserved. For this purpose the ligation to proteins of bis azo dyes, represented by Congo red and its derivatives with ... More
Pressure-induced conformational changes in a human Bence-Jones protein (Mcg).
AuthorsHerron JN, Ely KR, Edmundson AB
JournalBiochemistry
PubMed ID4041422
'The effect of high static pressures on the internal structure of the immunoglobulin light chain (Bence-Jones) dimer from the patient Mcg was assessed with measurements of intrinsic protein fluorescence polarization and intensity. Depolarization of intrinsic fluorescence was observed at relatively low pressures (less than 2 kbar), with a standard volume ... More
Photoincorporation of 4,4'-bis(1-anilino-8-naphthalenesulfonic acid) into the apical domain of GroEL: specific information from a nonspecific probe.
AuthorsSeale JW, Martinez JL, Horowitz PM
JournalBiochemistry
PubMed ID7779787
'The use of noncovalent hydrophobic probes such as bis-ANS has become increasingly popular in gaining structural information about protein structure and conformation. While these probes have provided rich information about protein conformation, specific information has been limited. In this report, we extend the usefulness of the probe bis-ANS by showing ... More
4,4(')-Dianilino-1,1(')-binaphthyl-5,5(')-disulfonate: report on non-beta-sheet conformers of Alzheimer's peptide beta(1-40).
AuthorsLeVine H
JournalArch Biochem Biophys
PubMed ID12127075
'The venerable fluorescent probe of protein hydrophobic regions, 4,4('')-dianilino-1,1('')-binaphthyl-5,5('')-disulfonate (bis-ANS), unexpectedly increases in fluorescence with soluble beta(1-40) in acidic buffer solutions but reacts weakly with amyloid fibrils while other hydrophobic probes react with the fibrils. CD analysis correlates reaction with the probe with random coil/mixed conformations and alpha-helical forms of ... More
Binding of recrystallized and chromatographically purified 8-anilino-1-naphthalenesulfonate to Escherichia coli lac repressor.
AuthorsYork SS, Lawson RC, Worah DM
JournalBiochemistry
PubMed ID363141
'8-Anilion-1-naphthalenesulfonate (Ans), recrystallized from water as the magnesium salt, contains a fluorescent impurity representing 0.3% of the absorbance at 351 nm. This impurity can be removed by Sephadex LH-20 chromatography. The chromatographic and spectral properties of this impurity suggest that it is bis(Ans), a dimer of Ans. This bis(Ans) impurity ... More
Energy transfer studies of the distances between the colchicine, ruthenium red, and bisANS binding sites on calf brain tubulin.
AuthorsWard LD, Seckler R, Timasheff SN
JournalBiochemistry
PubMed ID7522553
'Fluorescence energy transfer experiments were performed in order to measure the spatial separation between the colchine and Ruthenium Red binding sites, the high-affinity bisANS and Ruthenium Red sites, and the allocolchicine and high-affinity bisANS sites on calf brain tubulin. Energy transfer was observed between both colchicine and allocolchicine and Ruthenium ... More
The metastable state of nucleocapsids of enveloped viruses as probed by high hydrostatic pressure.
'Enveloped viruses fuse their membranes with cellular membranes to transfer their genomes into cells at the beginning of infection. What is not clear, however, is the role of the envelope (lipid bilayer and glycoproteins) in the stability of the viral particle. To address this question, we compared the stability between ... More
Structural transformations accompanying the assembly of bacteriophage P22 portal protein rings in vitro.
AuthorsMoore SD, Prevelige PE
JournalJ Biol Chem
PubMed ID11092883
'The Salmonella typhimurium bacteriophage P22 assembles an icosahedral capsid precursor called a procapsid. The oligomeric portal protein ring, located at one vertex, comprises the conduit for DNA entry and exit. In conjunction with the DNA packaging enzymes, the portal ring is an integral component of a nanoscale machine that pumps ... More
Bis(1,8-anilinonaphthalenesulfonate). A novel and potent inhibitor of microtubule assembly.
AuthorsHorowitz P, Prasad V, Luduena RF
JournalJ Biol Chem
PubMed ID6548750
'Two related compounds, 1,8-anilinonaphthalenesulfonate (1,8-ANS) and bis(1,8-anilinonaphthalenesulfonate) (Bis-ANS), are useful fluorescent probes for hydrophobic areas on protein molecules. Using fluorescence, we examined the binding of these compounds to bovine brain tubulin and found that Bis-ANS and 1,8-ANS bound to tubulin with Ki values of 2 and 25 microM, respectively. Bis-ANS ... More
Hydrophobic interaction of lysozyme and alpha-lactalbumin from equine milk whey.
AuthorsHaezebrouck P, Noppe W, Van Dael H, Hanssens I
JournalBiochim Biophys Acta
PubMed ID1504092
'From fluorescence measurements on mixtures of bis-ANS and equine lysozyme and from Ca(2+)-dependent hydrophobic interaction chromatography of equine lysozyme, it is demonstrated that Ca2+ binding induces a conformational change upon which hydrophobic regions in the protein become less accessible. Bis-ANS fluorescence titrations in the absence of Ca2+ and in 2 ... More
4,4'-Bis[8-(phenylamino)naphthalene-1-sulfonate] binding to human thrombins: a sensitive exo site fluorescent affinity probe.
AuthorsMusci G, Metz GD, Tsunematsu H, Berliner LJ
JournalBiochemistry
PubMed ID4016098
'The binding of the fluorescent probe 4,4''-bis[8-(phenylamino)naphthalene-1-sulfonate] (bis-ANS) to human alpha- and gamma-thrombins was investigated. Bis-ANS binds in a 1:1 complex to both forms of the enzyme, with Kd = 14.8 +/- 2.2 microM and 5.8 +/- 1.0 microM for alpha- and gamma-thrombin, respectively, at pH 7.0 [25 mM tris(hydroxymethyl)aminomethane, ... More
Mildly acidic pH activates the extracellular molecular chaperone clusterin.
'Many features of the chaperone action of clusterin are similar to those of the intracellular small heat shock proteins (sHSPs) that, like clusterin, exist in solution as heterogeneous aggregates. Increased temperature induces dissociation of some sHSP aggregates and an enhanced chaperone action, suggesting that a dissociated form is the active ... More
Probing the structure of the ligand binding cavity of lipocalins by fluorescence spectroscopy.
AuthorsPatel RC, Lange D, McConathy WJ, Patel YC, Patel SC
JournalProtein Eng
PubMed ID9278274
'The lipocalin superfamily constitutes a phylogenetically conserved group of more than 40 proteins that function in the binding and transport of a variety of physiologically important ligands. Members of this family subserve diverse functions as carriers of retinoids (retinol binding protein), odorants (odorant binding proteins), chromophores (insecticyanin, INS), pheromones (aphrodisin) ... More
Stabilization of tubulin by deuterium oxide.
AuthorsChakrabarti G, Kim S, Gupta ML, Barton JS, Himes RH
JournalBiochemistry
PubMed ID10074359
'Tubulin is an unstable protein when stored in solution and loses its ability to form microtubules rapidly. We have found that D2O stabilizes the protein against inactivation at both 4 and 37 degrees C. In H2O-based buffer, tubulin was completely inactivated after 40 h at 4 degrees C, but in ... More
Membrane potential and surface potential in mitochondria. Fluorescence and binding of 1-anilinonaphthalene-8-sulfonate.
AuthorsRobertson DE, Rottenberg H
JournalJ Biol Chem
PubMed ID6885812
'The effects of surface potential and transmembrane potential on the binding and fluorescence of 1-anilinonaphthalene-8-sulfonate (ANS) in suspensions of rat liver mitochondria was investigated. The binding of ANS is characterized by two classes of binding site: a high affinity (Kd = 10-50 microM), low capacity (n = 3-8 nmol/mg of ... More
Interaction of the antitumor compound cryptophycin-52 with tubulin.
AuthorsPanda D, Ananthnarayan V, Larson G, Shih C, Jordan MA, Wilson L
JournalBiochemistry
PubMed ID11087360
'Cryptophycin-52 (LY355703) is currently undergoing clinical evaluation for cancer chemotherapy. It is a potent suppressor of microtubule dynamics in vitro, and low picomolar concentrations appear to inhibit cancer cell proliferation at mitosis by stabilizing spindle microtubules. In the present study, using [(3)H]cryptophycin-52, we found that the compound bound to tubulin ... More
The exchangeable yeast ribosomal acidic protein YP2beta shows characteristics of a partly folded state under physiological conditions.
AuthorsZurdo J, Sanz JM, González C, Rico M, Ballesta JP
JournalBiochemistry
PubMed ID9236009
'The eukaryotic acidic ribosomal P proteins, contrary to the standard r-proteins which are rapidly degraded in the cytoplasm, are found forming a large cytoplasmic pool that exchanges with the ribosome-bound proteins during translation. The native structure of the P proteins in solution is therefore an essential determinant of the protein-protein ... More
Purification, amino terminal analysis, and peptide mapping of proteins after in situ postelectrophoretic fluorescent labeling.
AuthorsVera JC, Rivas CI, Cortés PA, Cárcamo JO, Delgado J
JournalAnal Biochem
PubMed ID3146233
'Proteins fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were stained in situ with either 5-(dimethylamino)-1-naphthalene sulfonyl chloride (dansyl chloride) or fluorescein isothiocyanate. This staining procedure can be carried out in less than 30 min without previous fixation of the proteins. It is not dependent on such factors as charge or ... More
Zinc induces exposure of hydrophobic sites in the C-terminal domain of gC1q-R/p33.
AuthorsKumar R, Peerschke EI, Ghebrehiwet B
JournalMol Immunol
PubMed ID12213329
'Endothelial cells and platelets are known to express gC1q-R on their surface. In addition to C1q, endothelial cell gC1q-R has been shown to bind high molecular weight kininogen (HK) and factor XII (FXII). However, unlike C1q, whose interaction with gC1q-R does not require divalent ions, the binding of HK to ... More
Studies on the interaction between Escherichia coli pyruvate oxidase and a detergent activator by utilization of the fluorescence probe bis(8-p-toluidino-1-naphthalenesulfonate).
AuthorsO'Brien TA, Gennis RB
JournalBiochemistry
PubMed ID369607
Reversible oligomerization and denaturation of the chaperonin GroES.
'The chaperonin GroEL can assist protein folding and normally acts with the co-chaperonin GroES. These Escherichia coli proteins are encoded on the same operon, with GroES positioned first. In this report, we have investigated the reversible folding of GroES. Using fluorescence anisotropy of dansyl-labeled GroES, intrinsic fluorescence, bis-ANS binding, sedimentation ... More
A fluorescence spectroscopic and molecular dynamics study of bis-ANS/protein interaction.
AuthorsBothra A, Bhattacharyya A, Mukhopadhyay C, Bhattacharyya K, Roy S
JournalJ Biomol Struct Dyn
PubMed ID9619517
'Despite emergence of bis-ANS as a major fluorescence probe of proteins structure, conformational and spectroscopic properties of protein/bis-ANS complexes remains largely unexplored. We have shown that fluorescence polarization of both ANS and bis-ANS is excitation wavelength dependent and this is a property of all protein-ANS/bis-ANS complexes studied. Bis-ANS excitation maximum ... More
Extrinsic fluorescent dyes as tools for protein characterization.
AuthorsHawe A, Sutter M, Jiskoot W,
JournalPharm Res
PubMed ID18172579
'Noncovalent, extrinsic fluorescent dyes are applied in various fields of protein analysis, e.g. to characterize folding intermediates, measure surface hydrophobicity, and detect aggregation or fibrillation. The main underlying mechanisms, which explain the fluorescence properties of many extrinsic dyes, are solvent relaxation processes and (twisted) intramolecular charge transfer reactions, which are ... More
Binding of Zn(II) ions to alpha-lactalbumin.
AuthorsPermyakov EA, Shnyrov VL, Kalinichenko LP, Kuchar A, Reyzer IL, Berliner LJ
JournalJ Protein Chem
PubMed ID1815583
'The binding of Zn(II) ions to human and bovine alpha-lactalbumin has been studied by fluorescence, scanning microcalorimetry, and proteolytic digestion. The intrinsic tryptophan fluorescence spectrum of Ca(II)-loaded alpha-lactalbumin is insensitive to Zn(II) binding to the strong cation binding sites (Zn:protein ratios up to 20), yet the thermal denaturation transition, as ... More
High salt-induced conversion of Escherichia coli GroEL into a fully functional thermophilic chaperonin.
AuthorsKusmierczyk AR, Martin J
JournalJ Biol Chem
PubMed ID10945996
'The GroE chaperonin system can adapt to and function at various environmental folding conditions. To examine chaperonin-assisted protein folding at high salt concentrations, we characterized Escherichia coli GroE chaperonin activity in 1.2 m ammonium sulfate. Our data are consistent with GroEL undergoing a conformational change at this salt concentration, characterized ... More
Multiple unfolding intermediates of human placental alkaline phosphatase in equilibrium urea denaturation.
AuthorsHung HC, Chang GG
JournalBiophys J
PubMed ID11721007
'Alkaline phosphatase is an enzyme with a typical alpha/beta hydrolase fold. The conformational stability of the human placental alkaline phosphatase was examined with the chemical denaturant urea. The red shifts of fluorescence spectra show a complex unfolding process involving multiple equilibrium intermediates indicating differential stability of the subdomains of the ... More
Fluorescence studies of nucleotide interactions with bovine adrenal chromogranin A.
AuthorsYoo SH, Albanesi JP, Jameson DM
JournalBiochim Biophys Acta
PubMed ID2378903
'The binding of the fluorescent probe bis-ANS to chromogranin A, the major protein of adrenal chromaffin vesicles, caused a marked enhancement and blue shift in the fluorescence emission spectrum. The emission maximum shifted from 515 nm to 480 nm and the yield increased approx. 75-fold upon addition of 10 microM ... More
1,1'-bis(anilino)-4-,4'-bis(naphtalene)-8,8'-disulfonate acts as an inhibitor of lipoprotein lipase and competes for binding with apolipoprotein CII.
AuthorsLookene A, Zhang L, Tougu V, Olivecrona G
JournalJ Biol Chem
PubMed ID12855707
'Lipoprotein lipase (LPL) is dependent on apolipoprotein CII (apoCII), a component of plasma lipoproteins, for function in vivo. The hydrophobic fluorescent probe 1,1''-bis(anilino)-4,4''-bis(naphthalene)-8,8''-disulfonate (bis-ANS) was found to be a potent inhibitor of LPL. ApoCII prevented the inhibition by bis-ANS, and was also able to restore the activity of inhibited LPL ... More
Protein conformational changes induced by 1,1'-bis(4-anilino-5-naphthalenesulfonic acid): preferential binding to the molten globule of DnaK.
AuthorsShi L, Palleros DR, Fink AL
JournalBiochemistry
PubMed ID8011619
'1,1''-Bis(4-anilino-5-naphthalenesulfonic acid) (bis-ANS), a hydrophobic fluorescent molecular probe which has been shown to bind to compact intermediate states of proteins (molten globules) and also to many nucleotide binding sites, induces a conformational change in DnaK by preferentially binding to its partially folded intermediate state (I) and thus shifting the equilibrium ... More
Flexible loop of beta 2-glycoprotein I domain V specifically interacts with hydrophobic ligands.
AuthorsHong DP, Hagihara Y, Kato H, Goto Y
JournalBiochemistry
PubMed ID11434778
'Beta2-glycoprotein I (beta2-GPI), which consists of four complement control protein modules and a distinctly folded fifth C-terminal domain, is an essential cofactor for the binding to phospholipids of anti-cardiolipin antibodies, isolated from patients with anti-phospholipid antibody syndrome, and its fifth domain has attracted attention as a specific phospholipid-binding site. We ... More
A peptide sequence-YSGVCHTDLHAWHGDWPLPVK [40-60]-in yeast alcohol dehydrogenase prevents the aggregation of denatured substrate proteins.
AuthorsBhattacharyya J, Santhoshkumar P, Sharma KK
JournalBiochem Biophys Res Commun
PubMed ID12849973
'The structural and functional characteristics of a yeast alcohol dehydrogenase (ADH) peptide (YSGVCHTDLHAWHGDWPLPVK, residues 40-60) have been studied in detail. The peptide is hydrophobic in nature, binds the hydrophobic probe bis-ANS, and is mostly present in a random coil conformation. It shows chaperone-like activity by preventing dithiothreitol (DTT)-induced aggregation of ... More
Acid pH-induced conformational changes in bovine liver rhodanese.
AuthorsHorowitz PM, Xu R
JournalJ Biol Chem
PubMed ID1527067
'The enzyme rhodanese is greatly stabilized in the range pH 4-6, and samples at pH 5 are fully active after several days at 23 degrees C. This is very different from results at pH greater than 7, where there is significant loss of activity within 1 h. A pH-dependent conformational ... More
Folding of the phage P22 coat protein in vitro.
AuthorsTeschke CM, King J
JournalBiochemistry
PubMed ID8399234
'Within infected Salmonella cells, newly synthesized 47-kDa phage P22 coat polypeptides fold without covalent modifications into assembly-competent subunits. Coat protein subunits interact with scaffolding protein to form the icosahedral procapsid precursor of the mature, T = 7, virions. In these lattices, the coat subunits form seven classes of local bonding ... More
Tobacco mosaic virus disassembly by high hydrostatic pressure in combination with urea and low temperature.
'We investigated the effect of low temperature and urea combined with high pressure on tobacco mosaic virus (TMV). The evaluation of its aggregation state and denaturation process was studied using gel filtration, transmission electron microscopy, and spectroscopic methods. The incubation at 2.5 kbar induced 18% dissociation, and decreasing of temperature ... 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
ATP hydrolysis is critical for induction of conformational changes in GroEL that expose hydrophobic surfaces.
AuthorsGorovits BM, Ybarra J, Horowitz PM
JournalJ Biol Chem
PubMed ID9054367
'The degree of hydrophobic exposure in the molecular chaperone GroEL during its cycle of ATP hydrolysis was analyzed using 1,1''-bis(4-anilino)naphthalene-5,5''disulfonic acid (bisANS), a hydrophobic probe, whose fluorescence is highly sensitive to the environment. In the presence of 10 mM MgCl2 and 10 mM KCl the addition of ATP, but not ... More
Characterization of a partially folded monomer of the DNA-binding domain of human papillomavirus E2 protein obtained at high pressure.
AuthorsFoguel D, Silva JL, de Prat-Gay G
JournalJ Biol Chem
PubMed ID9535893
'The pressure-induced dissociation of the dimeric DNA binding domain of the E2 protein of human papillomavirus (E2-DBD) is a reversible process with a Kd of 5.6 x 10(-8) M at pH 5.5. The complete exposure of the intersubunit tryptophans to water, together with the concentration dependence of the pressure effect, ... More
Binding of 9-anthroylcholine monitors the interactions of adenosine cyclic 3',5'-phosphate-dependent protein kinase with MgATP, substrates, and regulatory subunits.
AuthorsMalencik DA, Anderson SR
JournalJ Biol Chem
PubMed ID9852061
'The isolated catalytic subunit of cAMP-dependent protein kinase and smooth muscle myosin light chain kinase undergo interactions with the fluorescent dye 9-anthroylcholine (9AC) that are responsive to the two enzymes'' associations with substrates and effectors. Additionally, the binding of 9AC is highly sensitive to subtle structural or functional differences among ... More
Association of Escherichia coli lac repressor with poly[d(A-T)] monitored with 8-anilino-1-napthalenesulfonate.
AuthorsWorah DM, Gibboney KM, Yang LM, York SS
JournalBiochemistry
PubMed ID363142
'The association of lac repressor with poly[d(A-T)] was monitored with the fluorescent prob 8-anilino-1-naphthalenesulfonate (Ans). Excess poly[d(A-T)] decreased the emission intensity of the repressor--Ans complex by 30%. Fluorescence titrations indicated that 33 +/- 4 base pairs were required to bind all of the repressor. Sedimentation studies indicated, however, that all ... More
Role of hydration in the conformational transitions between unliganded and liganded forms of loop 13 of the Na+/glucose cotransporter 1.
AuthorsXia X, Wang G, Fang H
JournalBiochem Biophys Res Commun
PubMed ID14985114
'SGLT1 as a Na+/glucose cotransporter is inhibited by phlorizin, a phloretin 2''-glucoside that has strong interactions with the C-terminal loop 13 (residues 541-638). Here we investigated the effect of a partial substitution of glycerol for water in the medium on the stability and phlorizin-binding function of loop 13 using fluorescence ... More
Evaluation of hydrophobicity versus chaperonelike activity of bovine alphaA- and alphaB-crystallin.
AuthorsBhattacharyya J, Srinivas V, Sharma KK
JournalJ Protein Chem
PubMed ID11902669
'Calf lens alphaA-crystallin isolated by reversed-phase HPLC demonstrates a slightly more hydrophobic profile than alphaB-crystallin. Fluorescent probes in addition to bis-ANS, like cis-parinaric acid (PA) and pyrene, show higher quantum yields or Ham ratios when bound to alphaA-crystallin than to alphaB-crystallin at room temperature. Bis-ANS binding to both alphaA- and ... More
Equilibrium unfolding and conformational plasticity of troponin I and T.
AuthorsMartins SM, Chapeaurouge A, Ferreira ST
JournalEur J Biochem
PubMed ID12423346
'The structures and stabilities of recombinant chicken muscle troponin I (TnI) and T (TnT) were investigated by a combination of bis-ANS binding and equilibrium unfolding studies. Unlike most folded proteins, isolated TnI and TnT bind the hydrophobic fluorescent probe bis-ANS, indicating the existence of solvent-exposed hydrophobic domains in their structures. ... More
Folding intermediates of a model three-helix bundle protein. Pressure and cold denaturation studies.
AuthorsChapeaurouge A, Johansson JS, Ferreira ST
JournalJ Biol Chem
PubMed ID11278529
'The stability and equilibrium unfolding of a model three-helix bundle protein, alpha(3)-1, by guanidine hydrochloride (GdnHCl), hydrostatic pressure, and temperature have been investigated. The combined use of these denaturing agents allowed detection of two partially folded states of alpha(3)-1, as monitored by circular dichroism, intrinsic fluorescence emission, and fluorescence of ... More
4,4'-Bis (1-anilinonaphthalene 8-sulfonate) (bis-ANS): a new probe of the active site of myosin.
AuthorsTakashi R, Tonomura Y, Morales MF
JournalProc Natl Acad Sci U S A
PubMed ID267928
'The interaction of myosin subfragment-1 (S-1) with 4,4''-bis(1-anilinonaphthalene 8-sulfonate) (bis-ANS) has been studied by monitoring the fluorescence of the latter when the two components form a complex. Because ATP and ATP analogs partially displace complexed bis-ANS it has also been possible to study interactions of S-1 and nucleotides by using ... More
[The effect of phalloidin on stability of F- and G-actin]
AuthorsVedenkina NS, Kalinichenko LP, Permiakov EA
JournalMol Biol (Mosk)
PubMed ID8552063
'Intrinsic tryptophan fluorescence and fluorescence of a hydrophobic probe bis-ANS were used to study the effect of phalloidin, a bicyclic heptapeptide toxin, on stability of monomeric (G) and polymeric (F) actin. It was found that bis-ANS fluorescence is sensitive to the actin polymerization process. Phalloidin in concentrations from 1 to ... More
The perturbations of the native state of goat alpha-lactalbumin induced by 1,1'-bis(4-anilino-5-naphthalenesulfonate) are Ca2+-dependent.
AuthorsVanderheeren G, Hanssens I, Noyelle K, Van Dael H, Joniau M
JournalBiophys J
PubMed ID9788914
'In this work we have studied the interaction of the hydrophobic fluorescent probe 1,1''-bis(4-anilino-5-naphthalenesulfonate) (bis-ANS), with the native state of apo- and Ca2+-bound goat alpha-lactalbumin (GLA). In 10 mM Tris-HCl, pH 7.5, at 4 degrees C in 2 mM EGTA as well as at 37 degrees C in 2 mM ... More
A redox-sensitive loop regulates plasminogen activator inhibitor type 2 (PAI-2) polymerization.
AuthorsWilczynska M, Lobov S, Ohlsson PI, Ny T
JournalEMBO J
PubMed ID12682008
'Plasminogen activator inhibitor type 2 (PAI-2) is the only wild-type serpin that polymerizes spontaneously under physiological conditions. We show that PAI-2 loses its ability to polymerize following reduction of thiol groups, suggesting that an intramolecular disulfide bond is essential for the polymerization. A novel disulfide bond was identified between C79 ... More
Conformational changes of Newcastle disease virus envelope glycoproteins triggered by gangliosides.
AuthorsFerreira L, Villar E, Muñoz-Barroso I
JournalEur J Biochem
PubMed ID14728685
'We have investigated the conformational changes of Newcastle disease virus (NDV) glycoproteins in response to receptor binding, using 1,1-bis(4-anilino)naphthalene-5,5-disulfonic acid (bis-ANS) as a hydrophobicity-sensitive probe. Temperature- and pH-dependent conformational changes were detected in the presence of free bovine gangliosides. The fluorescence of bis-ANS was maximal at pH 5. The binding ... More
Divalent cation binding to erythrocyte spectrin.
AuthorsWallis CJ, Babitch JA, Wenegieme EF
JournalBiochemistry
PubMed ID8494881
'Erythrocyte spectrin dimers and separated alpha- and beta-spectrin chains bound 45Ca2+ after electrophoresis on native or sodium dodecyl sulfate-polyacrylamide gels, blotting, and 45Ca2+ overlay. Flow dialysis and equilibrium dialysis revealed two binding components: high-affinity, Ca(2+)-specific sites with kd = 4 x 10(-7) M and n = 100 +/- 20 per ... More
Bis-ANS as a specific inhibitor for microtubule-associated protein induced assembly of tubulin.
AuthorsMazumdar M, Parrack PK, Mukhopadhyay K, Bhattacharyya B
JournalBiochemistry
PubMed ID1633159
'5,5''-Bis[8-(phenylamino)-1-naphthalenesulfonate] (bis-ANS), the fluorescent probe which binds to tubulin, inhibits its assembly into microtubules [Horowitz et al. (1984) J. Biol. Chem. 259, 14647-14650]. The results described in this paper demonstrate that bis-ANS is quite distinct from other well-known microtubule inhibitors in its specificity of action. The inhibitory potentials of bis-ANS ... More
Inhibition of Escherichia coli RNA polymerase by bis(1-anilino-8-naphthalenesulfonate).
AuthorsWu FY, Wu CW
JournalBiochemistry
PubMed ID338032
Selective adsorption of bis(1-anilino-8-naphthalenesulfonate) to the multiple forms of lactic dehydrogenase.
AuthorsAnderson SR
JournalBiochemistry
PubMed ID4331332
Dimer formation from 1-amino-8-naphthalenesulfonate catalyzed by bovine serum albumin. A new fluorescent molecule with exceptional binding properties.
AuthorsRosen CG, Weber G
JournalBiochemistry
PubMed ID5388144
Mapping of hydrophobic sites on the surface of myosin and its fragments.
AuthorsBorejdo J
JournalBiochemistry
PubMed ID6838846
Urea-induced denaturation of beta-trypsin: an evidence for a molten globule state.
AuthorsBrumano MH, Oliveira MG
JournalProtein Pept Lett
PubMed ID15078201
The denaturation of beta-trypsin induced by urea was investigated by fluorescence and circular dichroism. A transient denatured state was found at 2 M urea in both intrinsic fluorescence spectrum and bis-(8-anilino-1-naphtalene sulfonate) (bis-ANS) binding. In addition, the absence of tertiary contacts and presence of secondary structure for this state, are ... More
The hydrophobic probe 4,4'-bis(1-anilino-8-naphthalene sulfonic acid) is specifically photoincorporated into the N-terminal domain of alpha B-crystallin.
AuthorsSmulders RH, de Jong WW
JournalFEBS Lett
PubMed ID9199512
Photoincorporation of the fluorescent probe 4,4'-bis(1-anilino-8-naphthalene sulfonic acid) (bis-ANS) can be used to locate solvent-exposed hydrophobic regions in proteins. We show that bis-ANS is specifically incorporated into the putative N-terminal domain of alpha B-crystallin. This incorporation diminishes the chaperone-like activity of alpha B-crystallin, suggesting that hydrophobic surfaces in the N-terminal ... More
The initiation codon AUG binds at a hydrophobic site on yeast 40S ribosomal subunits as revealed by fluorescence studies with bis (1,8-anilinonaphthalenesulfonate).
AuthorsLee JC, Yeh LC, Horowitz PM
JournalBiochimie
PubMed ID1747389
Binding studies of yeast 40S ribosome with bis (1,8-anilinonaphthalenesulfonate) (bis-ANS) revealed the binding of 3-4 molecules of bis-ANS per ribosome with a dissociation constant (Kd) of 1.45 microM. Binding of AUG to the 40S subunits resulted in a concentration-dependent decrease in the bis-ANS fluorescence without displacing all of the bound ... More
Active rhodanese lacking nonessential sulfhydryl groups has increased hydrophobic exposure not observed in wild-type enzyme.
AuthorsKaur Y, Ybarra J, Horowitz PM
JournalProtein J
PubMed ID15214496
Mutation of all nonessential cysteine residues to serines in rhodanese turns the enzyme into a form (C3S) that is fully active but less stable than wild type (WT). bis-ANS binding studies have shown that C3S has more hydrophobic exposure than WT, although both have similar secondary structures suggesting the flexibility ... More
Membrane association of sucrose synthase: changes during the graviresponse and possible control by protein phosphorylation.
AuthorsWinter H, Huber JL, Huber SC
JournalFEBS Lett
PubMed ID9459300
Sucrose synthase (SuSy) plays an important role in sucrose degradation and occurs both as a soluble and as a membrane-associated enzyme in higher plants. We show that membrane association can vary in vivo in response to gravistimulation, apparently involving SuSy dephosphorylation, and is a reversible process in vitro. Phosphorylation of ... More
Effect of self association of bis-ANS and bis-azo dyes on protein binding.
AuthorsStopa B, Konieczny L, Piekarska B, Roterman I, Rybarska J, Skowronek M
JournalBiochimie
PubMed ID9195042
A correlation was found between the ability of dyes (ANS, bis-ANS, Congo red, Evans blue) to form self-associated supramolecular structures in water and their tendency to form complexes with proteins. The self-association ability of dyes was measured as the resistance of a molecular sieve to their penetration. Quantitative evaluation of ... More
Rapid imaging, using a cooled charge-coupled-device, of fluorescent two-dimensional polyacrylamide gels produced by labelling proteins in the first-dimensional isoelectric focusing gel with the fluorophore 2-methoxy-2,4-diphenyl-3(2H)furanone.
AuthorsJackson P, Urwin VE, Mackay CD
JournalElectrophoresis
PubMed ID2466662
A new method for visualising proteins in two-dimensional polyacrylamide gels was developed. Proteins were labelled with the fluorophore 2-methoxy-2,4-diphenyl-3(2H)furanone (MDPF) while present in the first-dimensional gel after isoelectric focusing and subsequently electrophoresed into the second-dimensional gel. High resolution spot patterns were produced and compared with other methods of visualisation. A ... More
Interaction of Prodan with tubulin. A fluorescence spectroscopic study.
AuthorsMazumdar M, Parrack PK, Bhattacharyya B
JournalEur J Biochem
PubMed ID1740122
The compound 6-propionyl-2-(N,N-dimethyl)-aminonaphthalene (Prodan), an efficient fluorescent probe for proteins, is shown to bind to tubulin. Detailed experiments on fluorescence enhancement, anisotropy and energy transfer were carried out to unravel the nature of Prodan-tubulin interaction and the Prodan-binding site on tubulin. It was found that Prodan binds to tubulin at ... More
Fluorescent dyes as probes to study lipid-binding proteins.
AuthorsPastukhov AV, Ropson IJ
JournalProteins
PubMed ID14579352
We studied the equilibrium binding of two hydrophobic fluorescent dyes, ANS and bisANS, to four members of a family of intracellular lipid-binding proteins: IFABP, CRABP I, CRABP II, and ILBP. The spectral and binding parameters for the probes bound to the proteins were determined. Typically, there was a single binding ... More
Temperature-induced exposure of hydrophobic surfaces and its effect on the chaperone activity of alpha-crystallin.
AuthorsDas KP, Surewicz WK
JournalFEBS Lett
PubMed ID7649280
alpha-Crystallin, the major protein of the ocular lens, is known to have extensive similarities to small heat shock proteins and to act as a molecular chaperone. The exposure of hydrophobic surfaces on alpha-crystallin was studied by fluorescence spectroscopy using the hydrophobic probe bis-ANS. Upon heating the protein undergoes a conformational ... More
Interaction of dolastatin 10 with bovine brain tubulin.
AuthorsLudueña RF, Roach MC, Prasad V, Pettit GR
JournalBiochem Pharmacol
PubMed ID1540211
Dolastatin 10 is an unusual peptide of marine origin which binds to tubulin in the vinblastine/maytansine/phomopsin-binding region and potently inhibits mitosis. Using N,N'-ethylenebis(iodoacetamide) (EBI) and iodo[14C]acetamide as probes for the effects of ligands on the thiol groups of tubulin, we found that dolastatin 10 has effects on the sulfhydryls indistinguishable ... More
Formation of inter- and intramolecular disulfide bonds can activate cardiac troponin C.
AuthorsPutkey JA, Dotson DG, Mouawad P
JournalJ Biol Chem
PubMed ID8463206
Troponin C regulates contraction in striated muscle by alternating between the Ca(2+)-bound and apo conformations. We report here that spontaneous formation of an intramolecular disulfide bond between Cys-35 and Cys-84, or dimerization via an intermolecular disulfide bond between Cys-84 in cardiac troponin C, renders the protein Ca(2+)-independent when assayed in ... More
Modulating the intrinsic disorder in the cytoplasmic domain alters the biological activity of the N-methyl-D-aspartate-sensitive glutamate receptor.
AuthorsChoi UB, Kazi R, Stenzoski N, Wollmuth LP, Uversky VN, Bowen ME,
Journal
PubMed ID23782697
The NMDA-sensitive glutamate receptor is a ligand-gated ion channel that mediates excitatory synaptic transmission in the nervous system. Extracellular zinc allosterically regulates the NMDA receptor by binding to the extracellular N-terminal domain, which inhibits channel gating. Phosphorylation of the intrinsically disordered intracellular C-terminal domain alleviates inhibition by extracellular zinc. The ... More
Unique N-terminal arm of Mycobacterium tuberculosis PhoP protein plays an unusual role in its regulatory function.
AuthorsDas AK, Kumar VA, Sevalkar RR, Bansal R, Sarkar D,
Journal
PubMed ID23963455
Mycobacterium tuberculosis PhoP, a master regulator involved in complex lipid biosynthesis and expression of unknown virulence determinants, is composed of an N-terminal receiver domain and a C-terminal effector domain. The two experimentally characterized PhoP orthologs, from Escherichia coli and Salmonella enterica, display vastly different regulatory capabilities. Here, we demonstrate that ... More
ZG16p, an animal homolog of ß-prism fold plant lectins, interacts with heparan sulfate proteoglycans in pancreatic zymogen granules.
AuthorsKumazawa-Inoue K, Mimura T, Hosokawa-Tamiya S, Nakano Y, Dohmae N, Kinoshita-Toyoda A, Toyoda H, Kojima-Aikawa K,
JournalGlycobiology
PubMed ID21948871
ZG16p is a soluble 16 kDa pancreatic protein having structural similarities with plant ß-prism fold lectins such as the banana lectin BanLec and the jackfruit lectin jacalin. ZG16p is postulated to be involved in the formation of zymogen granules by interacting with proteoglycans (PGs) localized in pancreatic exocrine granule membranes, but ... More
The use of differential scanning fluorimetry to detect ligand interactions that promote protein stability.
AuthorsNiesen FH, Berglund H, Vedadi M,
JournalNat Protoc
PubMed ID17853878
Differential scanning fluorimetry (DSF) is a rapid and inexpensive screening method to identify low-molecular-weight ligands that bind and stabilize purified proteins. The temperature at which a protein unfolds is measured by an increase in the fluorescence of a dye with affinity for hydrophobic parts of the protein, which are exposed ... More