• Microbiology and Biotechnology Letters
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• v.21 no.2
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• pp.163-170
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• 1993

The effect of substrate micellization on the hydrolysis rate in the production of lysopho-sphatidylcholine (LPC) from phosphatidylcholine (PC) using hog pancreas phospholipase A2(PLA2) was studied. The optimal temperature and pH for the reactions in aqueous phase was found 42C and 7.2, respectively. For a given PC concentration, initial reaction rate was progressively increased with the addition of sodium deoxycholate (DOC), which could transform the bilayer of phospholipids into micellar structure.

• Proceedings of the Korean Biophysical Society Conference
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• 1996.07a
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• pp.35-35
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• 1996

Nitric oxide (NO) has been reported to have many roles in vivo ranging from the neurotransmitter in brain to the relaxant in smooth muscles. Recently, using inside-out patches, Bolotina et al. (1) showed that relaxing effect of NO is aortic smooth muscle is through direct activation of Ca2+-activated K+ channels (maxi-K), resulting in hyperpolarization. (omitted)

• Proceedings of the Korean Biophysical Society Conference
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• 1996.07a
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• pp.34-34
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• 1996

Previously we showed that $Ba^{2+}$ block of large conductance $Ca^{2+}$-activated $K^{+}$ (BK) channel was larger in the planar lipid bilayer formed with negatively-charged phosphatidylserine (PS) than neutral phosphatidylethanolamine (PE). In this work, have studied the blocking effect of two $K^{+}$ channel blockers with different mechanisms of action, $Ba^{2+}$ and tetraethylammonium (TEA), on BK channels of rat skeletal muscle. (omitted)itted)

• Proceedings of the Korean Biophysical Society Conference
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• 1996.07a
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• pp.27-27
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• 1996

SecA protein which has a pivotal role in the preprotein cranslocation across the inner membrane of Escherichia coli is a water-soluble protein with an unusual property of penetrating the membrane readily. An interesting and important question is what structural characteristics of SecA enables its ready penetration of lipid bilayer. The conformational properties of SecA in solution at 3$0^{\circ}C$, pH 7.5 were observed by hydrogen-tritium (HT) exchange, and denaturant-induced denaturation/renaturation and thermal unfolding. (omitted)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.473-476
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• 1999

PMOS capacitors with Ce-policide electrode were fabricated by the SADS method to study the effects of activation condition on the C-V characteristics. For the activation temperature of $600^{\circ}C$ , the capacitor using CoSi$_2$ formed from Co/Ti bilayer as diffusion source showed excellent C-V properties and the increase in V$_{th}$ with the increasing activation time. But impurties into the oxide.e.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.319.2-319.2
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• 2002

Chitin is a major component of the shells of crustacea such as crab. shrimp and crawfish. Renal dipeptidase (RDPase. EC 3.4.13.19), an ectoenzyme of renal proximal tubules. is covalently bound to outer leaflet of lipid bilayer via glycosylphosphatidylinositol (GPI)-anchor. The biological role of RDPase was suggested as the hydrolysis of dipeptide into free-amino acids before renal reabsorption. The underlying biochemical mechanism of decreased RDPase release was suggested as nitric oxide (NO) production. (omitted)

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.4
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• pp.135-139
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• 2004

The layered organic-inorganic hybrid compounds($C_6H_5CH_2NH_3)_2CuCl_4$ and ($NH_3C_6/H_4C_2H_4_6/H_4NH_3)CuCl_4$ have been directly synthesized. From the X-ray diffraction data and the organic guest size, the orientation of the intercalated organic amine was determined. The inorganic sheets consist of $CuCl_4^{2-}$layers of comer-sharing octahedra copper chloride. The protonated organic amine was intercalated into the $CuCl_4^{2-}$layers with bilayer structure for ($C_6H_5CH_2NH_3)_2CuCl_4$ and monolayer structure for ($NH_3C_6/H_4C_2H_4_6/H_4NH_3)CuCl_4$.

• Analytical Science and Technology
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• v.26 no.6
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• pp.395-400
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• 2013

The hydration and antimicrobial peptide effects on the lipid alignment on the surface of a thin glass plate were investigated by using the solid-state nuclear magnetic resonance spectroscopy. Pure 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphotidylcholine (POPC) lipid molecules were well aligned on the surface of a thin glass plate without direct hydration by placing the sample for a few days in the desiccator containing a saturated sodium phosphate dibasic solution, which provided 95% relative humidity. But there was a big difference between two lipid phases, the one of which was hydrated by placing the sample for a few days in the desiccator with 95% relative humidity without direct hydration and the other was directly hydrated by dropping water and then placed for a few days in the same desiccator. The surface mobility of POPC molecules in a lipid bilayer phase was much activated by water. While the time for the POPC to align on the glass plate surface was short, the time for the PG-1/POPC mixture to reach the its equilibrium state was long.

• Journal of Photoscience
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• v.12 no.2
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• pp.67-73
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• 2005

Fluorescent probe techniques were used to evaluate the effect of dibucaine.HCl on the physical properties (transbilayer asymmetric lateral mobility, annular lipid fluidity and protein distribution) of synaptosomal plasma membrane vesicles (SPMV) isolated from bovine cerebral cortex. An experimental procedure was used based on selective quenching of 1,3-di(l-pyrenyl)propane (Py-3-Py) by trinitrophenyl groups, and radiationless energy transfer from the tryptophans of membrane proteins to Py-3-Py. Dibucaine.HCl increased the bulk lateral mobility, and annular lipid fluidity in SPMV lipid bilayers, and had a greater fluidizing effect on the inner monolayer than the outer monolayer. The magnitude of increasing effect on annular lipid fluidity in SPMV lipid bilayer induced by dibucaine.HCl was significantly far greater than magnitude of increasing effect of the drug on the lateral mobility of bulk SPMV lipid bilayer. It also caused membrane proteins to cluster. These effects of dibucaine.HCl on neuronal membranes may be responsible for some, though not all, of the local anesthetic actions of dibucaine.HCl.

• BMB Reports
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• v.32 no.6
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• pp.561-566
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• 1999

CA(1-8)-ME(1-12) [CA-ME], composed of cecropin A(1-8) and melittin(1-12), is a synthetic antimicrobial peptide having potent antibacterial and antitumor activities with minimal hemolytic activity. In order to investigate the effects of the flexible hinge sequence, Gly-Ile-Gly, of CA-ME on antibiotic activity, CA-ME and three analogues, CA-ME1, CA-ME2, and CA-ME3, were synthesized. The Gly-Ile-Gly sequence of Ca-ME was deleted in CA-ME1 and replaced with Pro and Gly-Pro-Gly in CA-ME2 and CA-ME3, respectively. CA-ME1 and CA-ME3 showed a significant decrease in antitumor activity and phospholipid vesicle-disrupting ability. However, CA-ME2 showed similar antitumor and vesicle-disrupting activities, as compared with CA-ME. These results suggest that the flexibility or ${\beta}$-turn induced by Gly-Ile-Gly or Pro in the central part of CA-ME may be important in the electrostatic interaction of the N-terminus cationic ${\alpha}$-helical region with the cell membrane surface and the hydrophobic interaction of the C-terminus amphipathic ${\alpha}$-helical region with the hydrophobic acyl chains in the cell membrane. CA-ME3 exhibited lower antitumor and vesicle-disrupting activities than CA-ME and CA-ME2. This result suggests that the excessive ${\beta}$-turn structure caused by the Gly-Pro-Gly sequence in CA-ME3 seems to interrupt ion channel/pore formation in the lipid bilayer. We concluded that the appropriate flexibility or bilayer. We concluded that the appropriate flexibility or ${\beta}$-turn structure provided by the central hinge is responsible for the effective antibiotic activity of the antimicrobial peptides with the helix-hinge-helix structure.