• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.182-182
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• 1996

Annexin I is a member of the annexin family of calcium dependent phospholipid binding proteins and has anti-inflammatory activity by inhibiting phospholipase A$_2$ (PLA$_2$). Recent X-ray crystallographic study of annexin I identified six Ca$\^$2+/ binding bites, which was different types (type II, III) from the well-known EF-hand motif (type I). In this work, the structure of annexin I was studied at atomic level by using $^1$H, $\^$15/N and $\^$l3/C NMR(nuclear magnetic resonance) spectroscopy, and the effect of Ca$\^$2+/ binding on the structure of annexin I was studied, and compared with that of Mg$\^$2+/ binding, When Ca$\^$2+/ was added to annexin I, NMR peak change was occured in high- and low-field regions of $^1$H-NMR spectra. NMR peak change by Ca$\^$2+/ binding was different from that by Mg$\^$2+/ binding. Because annexin I is a larger protein with 35 kDa molecular weight, site-specific (amide-$\^$15/N, carbonyl-$\^$l3/C) labeling technique was also used. We were able to detect methionine, tyrosine and phenylalanine peaks respectively in $\^$13/C-NMR spectra, and each residue was able to be assigned by the method of doubly labeling annexin I with [$\^$13/C] carbonyl-amino acid and [$\^$15/N] amide-amino acid. In $\^$l3/C-NMR spectra of [$\^$13/C] carbonyl-Met labeled annexin I, we observed that methionine residues spatially located near Ca$\^$2+/ binding Sites Were Significantly effected by Ca$\^$2+/ binding. From UV spectroscopic data on the effect of Ca$\^$2+/ binding, we knew that Ca$\^$2+/ binding sites of annexin I have cooperativity in Ca$\^$2+/ binding. The interaction of annexin I with PLA$_2$ also could be detected by using heteronuclear NMR spctroscopy. Consequently, we expect that the anti-inflammatory action mechanism of annexin I may be a specific protein-protein interaction. The residues involved in the interaction with PLA$_2$ can be identified as active site by assigning NMR peaks effected by PLA$_2$ binding.

• Journal of Food Hygiene and Safety
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• v.7 no.2
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• pp.77-82
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• 1992

In order to investigate the protein binding characteristics of braD6n and hematoxy6n to bovine semm albumin (BSA), the fluorescence probe method was adopted. Brazilin and hematoxy6n showed strong binding affinity for BSA. It was also confirmed that hematoxy6n was bound to BSA stronger than braDlin. The association constants were decreased by the elevation of concentrations of brazilin and hematoxylin. It might be due to the complex formation of the probe and both compounds or the interaction between the probe-protein complex and both compounds. The bindings between both compounds and BSA were dependent on pH and ionic strength. It seems that electrostatic force as weD as hydrophobic force is involved in the binding of braD6n and bematoxylin to BSA.

• The Korean Journal of Nuclear Medicine
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• v.12 no.2
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• pp.1-5
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• 1978

For clinical application of radioreceptor assay, we studied preliminarily the distribution of estrogen receptor in various organs of rabbit by a dextran-charcoal method using $6,7-^3H-estradiol$. The results were expressed as binding index, which is the ratio of specific estradiol receptor binding radioactivity to total radioactivity. The materials consist of 5 female rabbits and 3 male rabbits. The results were as follows: 1) Female rabbits The binding index was highest in the uterine tissue. This binding index of the uterine tissue was 9.4 times that of the liver, 21.9 times that of the kidney, 24.6 times that of the brain, 28.1 times that of the lung and 65.7 times that of the muscle. 2) Male rabbits The binding index was highest in the liver and decreased in the order of the kidney, the testis, the lung, the brain and the muscle. It is suggested that the estrogen receptor is not confined to any specific target organ but is widely distributed in the various organs, to a different degree.

• Bulletin of the Korean Chemical Society
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• v.26 no.1
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• pp.136-138
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• 2005

High-performance frontal analysis (HPFA) was used for the determination of the binding constant of Sibuprofen to human serum albumin (HSA). This experiment was based on an Inertsil 100 Diol 5 column and sodium phosphate buffer (pH 7.4 and ionic strength of 0.17) as the mobile phase. The mixture of S-ibuprofen and HSA (70 $\mu$M) solution were directly injected into the HPFA column. An injection volume of 200 $\mu$L and a “estricted injection”method were applied to ensure the drug to be eluted as a zonal peak with a plateau. The unbound drug concentration was calculated from the peak height of the zonal peak. Scatchard analysis was used for evaluation of the binding constant (K) and binding affinity (nK) of S-ibuprofen to HSA, and the results were K = 2.833 ${\times}$ 10$^4$ [L mol$^{-1}$], nK = 4.935 ${\times}$ 10$^4$ [L mol$^{-1}$], respectively.

• Clinical and Experimental Reproductive Medicine
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• v.13 no.1
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• pp.29-38
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• 1986

In order to study the mechanism of follicular atresia, follicles were classified into the normal groups and the atretic ones, according to the criteria with or without corpus luteum, size of follicles, vascularization, status of granulose cells and the hypertrophy of theca layers in the porcine ovary. To estimate the binding capacity of human chorionic gonadotropin (hCG) receptor on the granulosa cells during atresia, hCG were iodinated by the chloramine-T method and then purified through the column chromatography. The concentration" of hCG receptor in each group were measured by the hCG receptor binding assay. Binding capacity in large normal follicles were 1.16%, but atretic ones were 0.45%. But in medium and small follicles (below 6mm in diameter), the binding capacity in normal follicles were 0.09%, but atretic ones were 0.05%, which was lower than those of large follicles. The present ( ) that the concentrations of hCG receptors on granulosa cells is decreased when the follicles become atretic and be used as a sort of creteria for the identification of follicles atresia.

• Bulletin of the Korean Chemical Society
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• v.28 no.3
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• pp.386-390
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• 2007

By use of a simple two-point extrapolation scheme estimating the correlation energies of the molecules along with the basis sets specifically targeted for extrapolation, we have shown that the MP2 basis set limit binding energies of large hydrogen-bonded complexes can be accurately predicted with relatively small amount of computational cost. The basis sets employed for computation and extrapolation consist of the smallest correlation consistent basis set cc-pVDZ and another basis set made of the cc-pVDZ set plus highest angular momentum polarization functions from the cc-pVTZ set, both of which were then augmented by diffuse functions centered on the heavy atoms except hydrogen in the complex. The correlation energy extrapolation formula takes the (X+1)-3 form with X corresponding to 2.0 for the cc-pVDZ set and 2.3 for the other basis set. The estimated MP2 basis set limit binding energies for water hexamer, hydrogen fluoride pentamer, alaninewater, phenol-water, and guanine-cytosine base pair complexes of nucleic acid by this method are 45.2(45.9), 36.1(37.5), 10.9(10.7), 7.1(6.9), and 27.6(27.7) kcal/mol, respectively, with the values in parentheses representing the reference basis set limit values. A comparison with the DFT results by B3LYP method clearly manifests the effectiveness and accuracy of this method in the study of large hydrogen-bonded complexes.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.247-250
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• 2011

We designed an effective screening method for double strand DNA (dsDNA) binders using DNA-modified magnetic particles. Hairpin DNA was immobilized on the surface of magnetic particle for a simple screening of dsDNA binding materials in a solution containing various compounds. Through several magnetic separation and incubation processes, four DNA-binding materials, DAPI, 9AA, AQ2A, and DNR, were successfully screened from among five candidates. Efficiency of screening was demonstrated by HPLC analysis using a C2/18 reverse-phase column. In addition, their relative binding strengths were verified by measuring the melting temperature ($T_m$). If hairpin DNA sequence is modified for other uses, this magnetic bead-based approach can be applied as a high-throughput screening method for various functional materials such as anti-cancer drugs.

• Journal of the Korea Society of Computer and Information
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• v.16 no.11
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• pp.173-178
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• 2011

In this paper, we propose an efficient seamless handover protocol in NEMO environment. Yokoda et al 4. proposed fast handover method with collaboration of access routers in local network and Teraoka et al. 1 showed fast handover method with collaboration of layers in mobile network. These methods can delay the time of overall binding update and increase packets loss when link of router is unstable because they transport packets through only one path or link of router. And they don't also mention redirection method of packets in their protocol in case of unstable link state of routers. The proposed protocol can execute fast binding update and reduce packets loss with collaboration of routers in mobile network.

• Bulletin of the Korean Chemical Society
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• v.25 no.9
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• pp.1314-1320
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• 2004

The adsorption and configuration of CO molecules adsorbed on W (110) and W (100) surfaces have been calculated by the atomic superposition and electron delocalization molecular orbital (ASED-MO) method. Referred to as the ASED-MO method, it has been used in the present study to calculate the geometries, binding energies, vibrational frequencies, orbital energies, reduced overlap population (ROP), and charges. From these results adsorption properties of ${\alpha}$-state and ${\beta}$-state were deduced. The calculated binding energies are in good agreement with the experimental result. On the W (110), the calculated average binding energies are 2.56 eV for the end-on configuration and 3.20 eV for the lying-down configuration. Calculated vibrational frequency is 1927 $cm^{-1}$ at a 1-fold site and 1161 $cm^{-1}$ at a long-bridge (2) site. These results are in reasonable agreement with experimental values. On the W(100) surface, calculated average binding energies of the end-on and the lying-down are 2.54 eV and 4.02 eV respectively. The differences for binding energy and configuration on the surfaces are explained on the basis of surface-atom coordination and atom-atom spacing. In the favored lyingdown CO configuration on the W(110) and W(100) surfaces, 4 ${\sigma}$ and 1 ${\pi}$ donation interactions, coupled with the familiar 5 ${\sigma}$ donation to the surfaces and back-donations to the CO 2 ${\pi}^{\ast}$ orbital, are responsible for adsorption to the surface.

• YAKHAK HOEJI
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• v.30 no.1
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• pp.31-41
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• 1986

Sarcolemmal membrane fraction from canine ventricle was isolated from the discarded pellet after the first homogenization in the isolation procedure of sarcoplasmic reticulum (Method 1) and the protein yield, purity, and sidedness of this preparation were compared to those of sarcolemmal fraction prepared by method of Lee et al. (Method 2) and a slight modification of original protocol of Jones et al. (Method 3). Method 1 differed from Method 2 essentially only in that vigorous homogenization was carried out by omnimixer and homogenization medium containing 30mM Tris-maleate was used in the first step. The sarcolemmal fraction was enriched from 45 to 50 and 29-fold in [$^3H$] ouabain, [$^3H$] DHA, [$^3H$] QNB binding and $Na^+$, $K^+$-ATPase activity, respectively, compared to homogenate. Total $Na^+$, $K^+$-ATPase activity of highly sarcolemma enriched fraction was 144.6$\pm$16.4$\mu\textrm{mol}$ Pi/mg protein/hr, which was about 85%, of total ATPase activity, and the yield of the preparation was 15.7 mg protein per 100g of starting ventricular tissue. The sarcolemmal preparation supported $^{45}Ca^{2+}$-uptake in the presence of ATP but this uptake was not dependent on oxalate. Sarcolemmal $Na^+$, $K^+$-ATPase activity and detectable [$^3H$] ouabain binding were increased about 32% and 35%, respectively, by pretreatment of sarcolemmal fraction with optimal concentration of sodium dodecylsulfate (0.3-0.4mg/mg protein), suggesting that this preparation contained about 24% of sealed rightside-out vesicles, 26% of sealed inside-out vesicles, and 5001o of freely permeable (leaky) form. This procedure showed the highest protein yield and leaky population, compared to Method 2 and 3. On the other hand, sarcolemmal fraction prepared by Method 2 and 3 showed low value in protein yield but comtained high population of inside-out (46%) and rightside-out (49%) vesicles, respectively, compared to present procedure (Method 1). The results indicate that vigorous homogenization decreases the population of sealed sarcolemmal vesicles but increases the sarcolemmal protein yield per gram tissue and that this procedure is available for further purification of sarcolemmal fraction and for the receptor binding study of sarcolemma.