• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2001.05a
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• pp.140-140
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• 2001

Porins are major outer membrane proteins which produce non-specific aqueous channels across the membrane that permit the diffusion into the bacterial cells of hydrophilic compounds including sugars, amino acids, and antibiotics. In some gram-negative organisms, antibiotic resistance can be induced by mutational loss of channel that causes a decrease in outer membrane permeability. (omitted)

• Membrane Journal
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• v.31 no.5
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• pp.293-303
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• 2021

Separation membranes used in water filtration, protein purification or biomedical filtration device frequently undergo membrane fouling for several reasons. The formation of biofilm on the membrane surface by bacteria causes a severe problem for durability of the membrane. For the protein separation, the membrane pores get blocked due to surface hydrophobicity of the membrane. There are several approaches controlling the membrane fouling and one of them is the incorporation of silver nanoparticles. Antibacterial properties of silver nanoparticles are well known and thus widely used in several applications. In this review, we have focused on the membranes where silver nanoparticles or its derivatives are either incorporated in the active layer of thin film composite membranes or uniformly distributed throughout the whole membranes.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.2
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• pp.85-94
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• 2000

The effects of ozone on chloroplast development in barley seedlings during greening was investigated based on ultrastructural changes in the chloroplasts and band pattern changes in the chloroplast thylakoid membrane proteins. In this analysis of the chloroplast thylakoid membrane thylakoid protein band pattern by SDS-PAGE, none of the 24-hour greening bands included were clearer than the control. This means that the ozone treatment produced a dealy in chloroplast development and decreased the amount of thylakoid membrane proteins. LHC II chloroplast band of developing barley seedlings treated with 0.5 and 1.0 ppm ozone during the last 4 hours of the 24-hour greening period was weaker than the other bands. This result indicates that ozone affects the LHC II protein complex of the chloroplast thylakoid membrane. When investigating the ultastructural changes in ozone-treated chloroplast, the main site affected by 0.5 ppm ozone was the chloroplast grana, thereby explaining the delayed chloroplast development during the early phase of greening. In addition, there was also a structural change in the stromal grana of the ozone treated chloroplast during the middle phase of greening. The effects of ozone on the chloroplast of barley seedlings during the last phase of 48-hour greening were more functionally inhibiting than structural changes.

• BMB Reports
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• v.37 no.3
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• pp.362-369
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• 2004

The human folate receptor (hFR) is a glycosylphosphatidylinositol (GPI) linked plasma membrane protein that mediates delivery of folates into cells. We studied the sorting of the hFR using transfection of the hFR cDNA into MDCK cells. MDCK cells are polarized epithelial cells that preferentially sort GPI-linked proteins to their apical membrane. Unlike other GPI-tailed proteins, we found that in MDCK cells, hFR is functional on both the apical and basolateral surfaces. We verified that the same hFR cDNA that transfected into CHO cells produces the hFR protein that is GPI-linked. We also measured the hFR expression on the plasma membrane of type III paroxysmal nocturnal hemoglobinuria (PNH) human erythrocytes. PNH is a disease that is characterized by the inability of cells to express membrane proteins requiring a GPI anchor. Despite this defect, and different from other GPI-tailed proteins, we found similar levels of hFR in normal and type III PNH human erythrocytes. The results suggest the hypothesis that there may be multiple mechanisms for targeting hFR to the plasma membrane.

• Membrane Journal
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• v.18 no.3
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• pp.214-218
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• 2008

Protain affinity membranes based on PES-BSA was preapared by the electrospinning method. The process problem caused by the electrospining was solved by using HFB having high solubility and boiling point. It was expecting that the mass production of protein affinity membrane would be possible with broad range of optimized temperature and humidity. BSA in the PES nanofiber was confirmed by the color change from colorless to violet during the biuret test. The buffer solution with DMSO showed that the amount of elution was 5 times higher than the one when the buffer solution without DMSO was used. This is due to the restriction effect of DMSO on the dissociation of L-tryptophan from BSA during the washing step.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.540-540
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• 2003

• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.185.2-185
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• 1994

No Abstract, See Full Text

• Journal of Life Science
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• v.13 no.4
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• pp.541-550
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• 2003

E2 glycoprotein of hepatitis C virus (HCV) comprises a surface of viral particle together with E1 glycoprotein, and is thought to be involved in the attachment of HCV viral particle to receptor (s) on the permissible cells including hepatocytes, B cells, T cells, and monocytes. We constructed a phage library expressing cellular proteins of hepatocytes on the phage surface, which turned out to be 8.8${\times}$$10^5$ cfu of diversity and carried inserts in 95% of library. We screened both cDNA phage library and 12-mer peptide library to identify the cellular proteins binding to E2 protein. Some intracellular proteins including tensin and membrane band 4.1 which are involved in signal transduction of survival and cytoskeleton organization, were selected from cDNA phage library through several rounds of panning and screening. On the contrary, membrane proteins such as CCR7, CKR-L2, and insulin-like growth factor-1 receptor were identified through screening of peptide library. Phages expressing peptides corresponding to those membrane proteins were bound to E2 protein specifically as determined by neutralization of binding assay. Since it is well known that HCV can infect T cells as well as hepatocytes, we examined to see if E2 protein can bind to CCR7, a member of C-protein coupled receptor family expressed on T cells, using CCR7 transfected tells. Human CCR7 cDNA was cloned into pcDNA3.1(-) vector and transfected into human embryonic kidney cell, 293T, and expressed on the surface of the cell as shown by flow cytometer. Binding assay of E2 protein using CCR7 transfected cells indicated that E2 protein bound to CCR7 by dose-dependent mode, giving rise to the possibility that CCR7 might be a putative cellular receptor for HCV.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.5
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• pp.745-751
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• 2003

This study was carried out to investigate whether peptide produced from wheat protein by enzyme hydrolysis can be used as a natural antimicrobial agent. Antimicrobial peptide was obtained from wheat protein hydrolyzed by 7 of pretense. The produced antimicrobial peptide was purified through ultrafiltration, membrane filtration and HPLC and molecular weight and amino acid sequence of the purified antimicrobial peptide were determined. Among hydrolysate produced from wheat protein by 7 of protease, antimicrobial activity was observed for the peptide obtained from Asp. saito protease. The Asp. saito protease did produce antimicrobial hydrolysate showing the highest antimicrobial activity at reaction condition of 37$^{\circ}C$ and pH 6.0, but not at reaction condition above 5$0^{\circ}C$. Wheat protein hydrolysate was fractionated by membrane filtration and showed antimicrobial activity between molecular weight 1,000~3,000. The antimicrobial activity fraction obtained by membrane filtration was separated through HPLC and showed antimicrobial activity in the peak of retention time 31.1~31.8 min. We could convince this hydrolysate as heat-stable peptide since antimicrobial activity was maintained after treated with heat for 15 min at 121$^{\circ}C$. Molecular weight of antimicrobial peptide identified by MALDI-mass was 1,633. Amino acid sequence of antimicrobial peptide was cysteine, glycine, prolin, prolin, prolin, valine, valine, alanine, alanine and arginine.

• Journal of the Korean Applied Science and Technology
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• v.28 no.2
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• pp.247-250
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• 2011

The excess volumes of mixing of benzyl alcohol and halothane in vesicle and in suspensions of several lipids have been determined at $25^{\circ}C$ it using a excess volume dilatometer. The potency of general anesthetics has long been known to correlate with lipid solubility. Denaturations of the vesicle, which is a sole membrane protein in the purple membrane of Halobacteriun Halobium, were studied by absorption changes at 280 nm and fluorescence changes at 330 nm and excess volume dilatometer. The particle size analysis of viscous polymer solutions by diffusional interchange is the key step by measurement. The excess volume of mixing in chitosan was found to be negative, whereas them of purple membrane, Halobacteriun Halobium and red membrane were positive in benzyl alcohol and halothane. This result was confirmed as Miller's supposition.