• BMB Reports
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• v.29 no.1
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• pp.1-10
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• 1996

The binding interaction of ethidium to a series of synthetic deoxyoligonucleotides containing a B-Z junction between left-handed Z-DNA and right-handed B-DNA, was studied. The series of deoxyoligonucleotides was designed so as to vary a dinucleotide step immediately adjacent to a B-Z junction region. Ethidium binds to the right-handed DNA forms and hybrid B-Z forms which contain a B-Z junction, in a highly cooperative manner. In a series of deoxyoligonucleotides, the binding affinity of ethidium with DNA forms which were initially hybrid B-Z forms shows over an order of magnitude higher than that with any other DNA forms, which were entirely in B-form DNA The cooperativity of binding isotherms were described by an allosteric binding model and by a neighbor exclusion model. The binding data were statistically compared for two models. The conformation of allosterically converted DNA forms under binding with ethidium is found to be different from that of the initial B-form DNA as examined by CD spectra. The ratio of the binding constant was interestingly correlated to the free energy of base unstacking and the conformational conversion of the dinucleotide. The more the base stacking of the dinucleotide is unstable, or the harder the conversion of B to A conformation, the higher the ratio of the binding constant of ethidium with the allosterically converted DNA forms and with the initial B-Z hybrid forms. DNA sequence around a B-Z junction region affects the binding affinity of ethidium. The results in this study demonstrate that ethidium could preferentially interact with unusual DNA structures.

• Archives of Pharmacal Research
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• v.12 no.3
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• pp.160-165
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• 1989

Binding of sulfaethidole to bovine serum albumin was studied by equilibrium dialysis, fluorescence probe technique, uv difference spectrophotometry and circular dichroism. Equilibrium dialysis method enabled us to estimate the total number of drug binding sites of albumin molecule. For sulfaethidole, albumin had 6 primary and 40 secondary binding sites. The primary and secondary binding constants were 0.9 * 10/sup 5/ M/sup -1/ and 0.2 * 10/sup 6/ M/sup -1/, respectivitely. 1-Anilino-8-naphthalenesulfonate (ANS) and 2-(4-hydroxylbenzeneazo)- benzoic acid (HBAB) were used as the fluorescence probe and the uv spectrophotometric probe, respectively. In fluorescence probe technique, results indicated that the number of higher affinity drug binding site of albumin was 1 and the number of lower affinity drug binding sites of albumin was 3, and the primary and secondary drug binding constants for bovine serum albumin were 2.15 * 10/sup 5/M/sup -1/ and 1.04 * 10/sup 5/ M/sup -1/, respectively. In uv difference spectrophotometry, binding sites were 3 and binding constant was 1.88 * 10/sup 5/M/sup -1/. The above spectrophotometry, binding sites were 3 and binding constant was 1.88 * 10/sup 5/M/sup -1/. The above results suggest that several different methods should be used in ompensation for insufficient information about drug binding to albumin molecule given by only one method.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.537-540
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• 2006

Over the past few decades, a considerable number of studies on the durability of concrete have been carried out extensively. A lot of improvements have been achieved especially in modeling of ionic flows. However, the majority of these researches have not dealt with the chloride binding isotherm based on the mechanism, although chloride binding capacity can significantly impact on the total service life of concrete under marine environment. The purpose of this study is to develop the model of chloride binding isotherm based on the individual mechanism. It is well known that chlorides ions in concrete can be present; free chlorides dissolved in the pore solution, chemical bound chlorides reacted with the hydration compounds of cement, and physical bound attracted to the surface of C-S-H grains. First, sub-model for water soluble chloride content is suggested as a function of pore solution and degree of saturation. Second, chemical model is suggested separately to estimate the response of binding capacity due to C-S-H and Friedel's salt. Finally, physical bound chloride content is estimated to consider a surface area of C-S-H nano-grains and the distance limited by the Van der Waals force. The new model of chloride binding isotherm suggested in this study is based on their intrinsic binding mechanisms and hydration reaction of concrete. Accordingly, it is possible to characterize chloride binding isotherm at the arbitrary stage of hydration time and arbitrary location from the surface of concrete. Comparative study with experimental data of published literature is accomplished to validity this model.

• Journal of Applied Biological Chemistry
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• v.43 no.3
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• pp.131-135
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• 2000

Human polymorphonuclear neutrophils undergo diaphoresis after a selectin-mediated rolling on the endothelial cells of the blood vessel wall. Extravasation is believed to be an integrin-mediated process. Galectin-1 is a small dimeric beta-galactoside-binding protein synthesized by the endotherial cells and present in the perivascular connective tissue. In this study we suggest the possible role of galectin-1 in extravasation of the activated neutrophils. MAL lectin binding study showed, that f-MetLeuPhe-activated neutrophils decrease surface sialylation and increase galectin-1 binding via exposure of new galectin-1 binding sites. Desialylated HL-60 cells also show the same decrease in MAL binding and increase in galectin-1 binding, an increase which was not observed in the presence of lactose. Galectin-1 blotting analysis detected two possible major ligands (approximately 120 and 160 kDa) of galectin-1 from the desialylated HL-60 cell lysates.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.242.3-243
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• 2003

The compound of 2"-O-benzoylcinnamaldehyde(CB-ph) is a derivative of 2"-hydroxycinnamaldehyde whcih is a methanol extract of cinnamomum cassia blume. It"s a new anti-cancer agent which has been showed to inhibit the growth of various tumor cells in vitro and in vivo. In order to investigate the effective drug concentration and bio-distribution of CB-ph, the plasma protein binding was studied. In this study, the degree of the binding of Cb-ph to various serum proteins, the binding parameters, the binding site of CB-ph in human serum albumin, and the effect of some extensive protein-binding drugs on the protein binding of CB-ph in human serum ablumin were investigated respectively by ultrafilteration and fluorescence spectrometry. (omitted)

• Language and Information
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• v.15 no.1
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• pp.63-78
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• 2011

This study investigates the binding behavior of the Korean anaphor 'caki', which has been regarded thus far as a long-distance anaphor (LDA). Given that even local anaphors can be bound long-distance when they function as exempt anaphors in certain languages (Pollard and Sag 1992; Kim and Yoon 2009a, b), I investigated the binding behavior of LD-bound 'caki', in order to determine whether LD-bound 'caki' differs from LD-bound 'caki-casin' in the same contexts. In the experiment, subjects were required to rate the grammaticality of Korean sentences representing various types of LD binding of 'caki' and to determine whether the sloppy or the strict reading was more prominent in elliptical VPs containing the anaphor. The results are discussed with respect to the typology of LDAs proposed by Cole, Hermon and Huang (2001).

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2317-2325
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• 2014

P-glycoprotein (P-gp) is a member of the ATP-Binding Cassette transporter superfamily and mediates transmembrane efflux of many drugs. Since it is involved in multi-drug resistance activity in various cancer cells, the development of P-gp inhibitor is one of the major concerns in anticancer therapy. Human P-gp protein has at least two "functional" drug binding sites that are called "H" site and "R" site, hence it has multi-binding-specificities. Though the amino acid residues that constitute in drug binding pockets have been proposed by previous experimental evidences, the shapes and the binding poses are not revealed clearly yet. In this study, human P-gp structure was built by homology modeling with available crystal structure of mouse P-gp as a template and docking simulations were performed with inhibitors such as verapamil, hoechst33342, and rhodamine123 to construct the interaction between human P-gp and its inhibitors. The docking simulations were performed 500 times for each inhibitor, and then the interaction frequency of the amino acids at the binding poses was analyzed. With the analysis results, we proposed highly contributing residues that constitute binding pockets of the human P-gp for the inhibitors. Using the highly contributing residues, we proposed the locations and the shapes of verapamil binding site and "R" site, and suggested the possible position of "H" site.

• Journal of Life Science
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• v.13 no.5
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• pp.746-750
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• 2003

Lactose operon contains two CRP binding sites at promoter(CRP1 site) and operator(CRP2 site) regions at lac operon. CRP protein can bind to both sites with the different binding affinity. CRP1 site, major CRP binding site, acts the transcription activation with the fully unknown mechanism by binding of CRP. In this study, the binding affinities of CRP1 site and CRP2 site were measured with the fluorescein-labeled oligomers, which contain CRP1 site and the three different spacing sequences between GTGA and TCAC at CRP2 site. Results showed that CRP:cAMP complex bound to CRP1 site 3 times more strongly than CRP2 site and the base spacing between GTGA and TCAC was not the only factor to affect the binding affinity of CRP to CRP2 site.

• The Korean Journal of Physiology and Pharmacology
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• v.6 no.2
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• pp.109-112
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• 2002

The signal pathways involved in the regulation of AP-1 DNA binding activity in long-term nicotine stimulated bovine adrenal medullary chromaffin (BAMC) cells have not been well characterized. To understand the involvement of second messengers in the regulation of AP-1 DNA binding activity, the present study was designed to define the time-course for inhibition of nicotine-induced responses by cholinergic antagonists, $Ca^{2+}$ and calmodulin (CaM) antagonists, and calcium/calmodulin-dependent protein kinase (CaMK) II inhibitor using electrophoretic mobility shift assay. Nicotine $(10{\mu}M)$ stimulation increased AP-1 DNA binding activity at 24 hr after treatment. Posttreatment with hexamethonium (1 mM) plus atropine $(1{\mu}M)$ (HA), nimodipine $(1{\mu}M),$ or calmidazolium $(1{\mu}M)$ at 0.5, 3, and 6 hr after the nicotine treatment significantly inhibited the AP-1 DNA binding activity increased by long-term nicotine stimulation. However, posttreatment with HA, nimodipine, or calmidazolium at 9 or 12 hr after the nicotine treatment did not affect the nicotine-induced increase of AP-1 DNA binding activity. The pretreatment of BAMC cells with various concentrations of KN-62 inhibited the increase of AP-1 DNA binding activity induced by nicotine in a concentration-dependent manner. KN-62 $(10{\mu}M)$ posttreatment beginning at 0.5, 3, or 6 hr after the nicotine treatment significantly inhibited the increase of AP-1 DNA binding activity. However, KN-62 posttreatment beginning at 9 or 12 hr after the nicotine treatment did not affect the increase of AP-1 DNA binding activity. This study suggested that stimulation (for at least 6 hr) of nicotinic receptors on BAMC cells was necessary for increase of AP-1 DNA binding activity, and activation of $Ca^{2+},$ CaM, and CaMK II up to 6 hr at least seemed to be required for the increase of nicotine-induced AP-1 DNA binding activity.

• Archives of Pharmacal Research
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• v.23 no.4
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• pp.360-366
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• 2000

The in vivo binding of dopamine (DA) radioligands to $D_2$receptors can be affected by competition with endogenous dopamine. In the present study, we used a brain slice preparation that provides more controlled conditions than in vivo preparations in order to examine the relationship between synaptic DA and the binding of [$^3H$] raclopride to $D_2$receptors. We also estimated the synaptic DA concentration in rat striatal slices by determining the changes in [$^3H$] raclopride binding. To correlate the changes in [$^3$H]raclopride binding with the concentration of synaptic DA, the kinetic parameters were determined. [$^3H$] Raclopride reached equilibrium binding conditions within two hours. The K value for DA in inhibiting [$^3$H]raclopride binding was about 2.2 nM. The increase in synaptic DA evoked by electrical stimulation decreased the striatal binding of [$^3H$] raclopride in a frequency-dependent manner. Increases in the DA concentration evoked by amphetamine (AMPH) or cocaine decreased [$^3H$] raclopride binding by 74% or 20%, respectively, corresponding to increases in the synaptic DA concentrations of 1.6 nM or 0.6 nM, respectively. Pargyline also decreased [$^3H$] raclopride binding by 36%corresponding at a concentration of 1.2 nM. In contrast, the depletion of synaptic DA by $\alpha$-methyl-p-tyrosine ($\alpha$-MpT) increased the specific binding of [$^3H$] raclopride by 43%when the DA concentration was decreased to 0.7 nM. The changes in the DA concentration at the synapse were responsible for the changes in the striatal binding of [$^3H$] raclopride. The values calculated in this study may therefore approximate the changes in the synaptic DA concentration in rat striatal slices following manipulation.