Isolation and partial characterization of a bacteriocin produced by <i>Pediococcus pentosaceus</i> K23-2 isolated from Kimchi

Shin, M.S.,Han, S.K.,Ryu, J.S.,Kim, K.S.,Lee, W.K. Blackwell Publishing Ltd 2008 Journal of Applied Microbiology Vol.105 No.2

<P>Abstract</P><P>Aims: </P><P>Screening and partial characterization of a bacteriocin produced by <I>Pediococcus pentosaceus</I> K23-2 isolated from Kimchi, a traditional Korean fermented vegetable.</P><P>Methods and Results: </P><P>A total of 1000 lactic acid bacteria were isolated from various Kimchi samples and screened for the production of bacteriocin. Pediocin K23-2, a bacteriocin produced by the <I>Pediococcus pentosaceus</I> K23-2 strain, showed strong inhibitory activity against <I>Listeria monocytogenes</I>. The bacteriocin activity remained unchanged after 15 min of heat treatment at 121°C or exposure to organic solvents; however, it diminished after treatment with proteolytic enzymes. The bacteriocin was maximally produced at 37°C, when the pH of the culture broth was maintained at 5·0 during the fermentation, although the optimum pH for growth was 7·0. The molecular weight of the bacteriocin was about 5 kDa according to a tricine SDS-PAGE analysis.</P><P>Conclusions: </P><P><I>Pediococcus pentosaceus</I> K23-2 isolated from Kimchi produces a bacteriocin, which shares similar characteristics to the Class IIa bacteriocins. The bacteriocin is heat stable and shows wide antimicrobial activity against Gram-positive bacteria, especially <I>L. monocytogenes</I>.</P><P>Significance and Impact of the Study: </P><P>Pediocin K23-2 and pediocin K23-2-producing <I>P. pentosaceus</I> K23-2 could potentially be used in the food and feed industries as natural biopreservatives, and for probiotic application to humans or livestock.</P>

Synthesis and Thermoelectric Properties of Ce1−z Pr z Fe4−x Co x Sb12 Skutterudites

Song, K. M.,Shin, D. K.,Jang, K. W.,Choi, S. M.,Lee, S.,Seo, W. S.,Kim, I. H. Springer Science + Business Media 2017 Journal of electronic materials Vol.46 No.5

<P>p-Type Ce1-z Pr (z) Fe4-x Co (x) Sb-12 skutterudites were prepared by encapsulated melting, quenching, annealing, and hot pressing. While the skutterudite phase was successfully synthesized, a small amount of the secondary phase (FeSb2) was observed. According to the scanning electron microscope analysis, (Ce,Pr)Sb-2 phases were also observed for Co-substituted specimens (x = 0.5). The electrical conductivity decreased with increasing temperature, implying a degenerate semiconductor behavior, and also decreased with increasing Co contents. All specimens showed p-type characteristics having positive signs of the Hall coefficient and the Seebeck coefficient. The Seebeck coefficient increased with increasing temperature and reached a maximum value at 823 K. The power factor (PF) increased with decreasing Co content and Ce0.75Pr0.25 Fe4Sb12 showed a peak value of PF = 3.2 mW m(-1) K-2 at 823 K. The electronic thermal conductivity decreased with increasing Co contents and the lattice thermal conductivity decreased with decreasing Ce and Co contents at high temperature. The thermal conductivity increased at temperatures above 623 K due to bipolar conduction. The dimensionless figurea of pound merit (ZT) showed a maximum value of ZT = 0.84 at 823 K for Ce0.25Pr0.75Fe4Sb12.</P>

Effect of Antimuscarinic Autoantibodies in Primary Sjögren’s Syndrome

Kim, N.,Shin, Y.,Choi, S.,Namkoong, E.,Kim, M.,Lee, J.,Song, Y.,Park, K. SAGE Publications 2015 Journal of dental research Vol.94 No.5

<P>The presence of functional autoantibodies against the muscarinic type 3 receptor (M3R) has been reported in primary Sjogren's syndrome (pSS). However, the pathogenic role of these autoantibodies in pSS development remains to be elucidated. In this experiment, we investigated a pathologic role of pSS autoantibodies (pSS IgG) associated with downregulation of the major histocompatibility complex I (MHC I) molecule with M3R through internalization. Anti-M3R autoantibodies in purified control and pSS IgG were detected using 4 synthesized cyclic M3R peptides by enzyme-linked immunosorbent assay. The binding reactivity of pSS IgG to M3R in situ was analyzed by a dual immunostaining method. Surface expression, interaction, and internalization of M3R with MHC I were analyzed by immunofluorescence confocal microscopy and biochemical assays. Synthetic cyclic peptides M3RP(205-221) and M3RP(520-527) showed significantly high reactivity with pSS IgG compared to the control IgG or the other 3 peptides (P < 0.05). Significantly high reactivity of pSS IgG to M3R in situ was observed. PSS IgG increased the interaction of membrane M3R with MHC I and induced their internalization in primary human submandibular gland cells. The pSS IgG-induced internalization of M3R with MHC I was significantly inhibited by the cholesterol-sequestering drug filipin. Our novel findingnamely, strong downregulation of the membrane MHC I with M3R through internalization of the cholesterol-rich microdomain associating with anti-M3R autoantibodiescould be an important mechanism contributing to the impaired salivation seen in pSS and linking secretory hypofunction to autoimmune pathogenesis.</P>

OGLE-2011-BLG-0265Lb: A JOVIAN MICROLENSING PLANET ORBITING AN M DWARF

Skowron, J.,Shin, I.-G.,Udalski, A.,Han, C.,Sumi, T.,Shvartzvald, Y.,Gould, A.,Dominis Prester, D.,Street, R. A.,Jørgensen, U. G.,Bennett, D. P.,Bozza, V.,Szymań,ski, M. K.,Kubiak, M.,Pietrzy
IOP Publishing 2015 The Astrophysical journal Vol.804 No.1

<P>We report the discovery of a Jupiter-mass planet orbiting an M-dwarf star that gave rise to the microlensing event OGLE-2011-BLG-0265. Such a system is very rare among known planetary systems and thus the discovery is important for theoretical studies of planetary formation and evolution. High-cadence temporal coverage of the planetary signal, combined with extended observations throughout the event, allows us to accurately model the observed light curve. However, the final microlensing solution remains degenerate, yielding two possible configurations of the planet and the host star. In the case of the preferred solution, the mass of the planet is M-p = 0.9 +/- 0.3 M-J, and the planet is orbiting a star with a mass M = 0.22 +/- 0.06 M-circle dot. The second possible configuration (2 sigma away) consists of a planet with M-p = 0.6 +/- 0.3M(J) and host star with M = 0.14 +/- 0.06M(circle dot). The system is located in the Galactic disk 3-4 kpc toward the Galactic bulge. In both cases, with an orbit size of 1.5-2.0 AU, the planet is a 'cold Jupiter'-located well beyond the 'snow line' of the host star. Currently available data make the secure selection of the correct solution difficult, but there are prospects for lifting the degeneracy with additional follow-up observations in the future, when the lens and source star separate.</P>

Induction of Cell Death in Human Macrophages by a Highly Virulent Korean Isolate of <i>Mycobacterium tuberculosis</i> and the Virulent Strain H37Rv

Sohn, H.,Lee, K.-S.,Kim, S.-Y.,Shin, D.-M.,Shin, S.-J.,Jo, E.-K.,Park, J.-K.,Kim, H.-J. Blackwell Publishing Ltd 2009 Scandinavian journal of immunology Vol.69 No.1

<P>Abstract</P><P>Recent studies have suggested that virulent strains of <I>Mycobacterium tuberculosis</I> induce apoptosis in macrophages less often than do attenuated strains. K-strain, which belongs to the Beijing family, is the most frequently isolated clinical strain of <I>M. tuberculosis</I> in Korea. In this study, we investigated the differential induction of cell death in human monocytic THP-1 cells by K-strain and H37Rv, a virulent but laboratory-adapted strain of <I>M. tuberculosis</I>. Although no significant difference in growth rate was observed between the cells exposed to K-strain and those exposed to H37Rv, the levels of protective cytokines such as tumour necrosis factor (TNF)-&agr;, interleukin (IL)-6 and IL-12p40 were lower in K-strain-infected cells than in H37Rv-infected cells. Cell viability assays showed that both K-strain and H37Rv, but not heat- or streptomycin-killed bacteria, induced THP-1 cell death in a TNF-independent manner. In contrast, double staining with fluorochrome-labelled inhibitors of caspase and propidium iodide and lactate dehydrogenase release assays revealed that K-strain induced significantly higher levels of necrotic cell death, rather than apoptosis, in THP-1 cells than did H37Rv. Anti-apoptotic <I>Bcl-2</I>, <I>Mcl-1</I>, <I>Bfl-1</I> and <I>Bcl-xL</I> in the cells were significantly upregulated following infection with K-strain compared with H37Rv, whereas <I>Bax</I> was slightly upregulated in response to infection with both H37Rv and K-strain. These results suggest that the highly virulent K-strain keeps cellular apoptosis as a host defense mechanism to a minimum and induces necrosis in macrophages.</P>

부자 Butanol Fraction이 가토 심장근 Microsomal Na⁺-K⁺-activated ATPase 활성도에 미치는 영향부자 Butanol Fraction이 가토 심장근 Microsomal Na⁺-K⁺-activated ATPase 활성도에 미치는 영향

신상구(S.G. Shin),임정규(J.K. Lim),박찬웅(C.W. Park),김명석(M.S. Kim) 대한약리학회 1976 대한약리학잡지 Vol.12 No.1

Aconiti tuber butanol fraction shows positive inotropic effect on the isolated atrium of rabbit heart. To investigate the mechanism, the effect on microsomal ATPase activity of rabbit heart is observed. The microsomal fraction which contains the Na⁺- and K⁺-activated ATPase in the presence of Mg⁺⁺ is isolated from the left ventricle of rabbit heart. The microsomal ATPase activity is maximally stimulated at Na⁺ and K⁺ concentration of 100 mM and 10 mM respectively. Microsomal Na⁺-K⁺-activated ATPase is inhibited by ouabain and Aconiti tuber butanol fraction. Ouabain and Aconiti tuber butanol fraction depress Na⁺-stimulation on microsomal ATPase activity, and the inhibitory effects are not completely reversed at Na⁺ concentration of 300 mM. Also, K⁺-stimulation on microsomal ATPase activity is inhibited by ouabin and Aconiti tuber butanol fraction and the inhibitions are not compeletely reversed at K⁺ concentration of 30 mM. It is, therefore, suggested that the inhibitory effect of Aconiti tuber butanol fraction on the microsomal ATPase activity may contribute to leading to the positive inotropic effect.

A novel chimeric promoter that is highly responsive to hypoxia and metals

Lee, J-Y,Lee, Y-S,Kim, J-M,Kim, K L,Lee, J-S,Jang, H-S,Shin, I-S,Suh, W,Jeon, E-S,Byun, J,Kim, D-K Nature Publishing Group 2006 Gene Therapy Vol.13 No.10

To develop a potent hypoxia-inducible promoter, we evaluated the usefulness of chimeric combinations of the (Egr-1)-binding site (EBS) from the Egr-1 gene, the metal-response element (MRE) from the metallothionein gene, and the hypoxia-response element (HRE) from the phosphoglycerate kinase 1 gene. In transient transfection assays, combining three copies of HRE (3 × HRE) with either EBS or MRE significantly increased hypoxia responsiveness. When a three-enhancer combination was tested, the EBS–MRE-3 × HRE (E–M–H) gave a hypoxia induction ratio of 69. The expression induced from E–M–H-pGL3 was 2.4-fold higher than that induced from H-pGL3 and even surpassed the expression from a human cytomegalovirus promoter-driven vector. The high inducibility of E–M–H was confirmed by validation studies in different cells and by expressing other cDNAs. Gel shift assays together with functional overexpression studies suggested that increased levels of hypoxia-inducible factor 1α, metal transcription factor-1 and Egr-1 may be associated with the high inducibility of the E–M–H chimeric promoter. E–M–H was also induced by hypoxia mimetics such as Co<SUP>2+</SUP> and deferoxamine (DFX) and by hydrogen peroxide. Gene expression from the E–M–H was reversible as shown by the reduced expression of the transgene upon removal of inducers such as hypoxia and DFX. In vivo evaluation of the E–M–H in ischemic muscle revealed that erythropoietin secretion and luciferase and LacZ expression were significantly higher in the E–M–H group than in a control or H group. With its high induction capacity and versatile means of modulation, this novel chimeric promoter should find wide application in the treatment of ischemic diseases and cancer.Gene Therapy (2006) 13, 857–868. doi:10.1038/sj.gt.3302728; published online 9 February 2006

Performance and carrier transport analysis of In_0.7Ga_0.3As quantum-well MOSFETs with Al₂O₃/HfO₂ gate stack

Son, S.W.,Park, J.H.,Baek, J.M.,Kim, J.S.,Kim, D.K.,Shin, S.H.,Banerjee, S.K.,Lee, J.H.,Kim, T.W.,Kim, D.H. Pergamon Press ; Elsevier Science Ltd 2016 Solid-State Electronics Vol.123 No.-

In this paper, we have fabricated and characterized In<SUB>0.7</SUB>Ga<SUB>0.3</SUB>As quantum-well (QW) metal-oxide-semiconductor field-effect-transistors (MOSFETs). We have employed the gate dielectric of the Al<SUB>2</SUB>O<SUB>3</SUB>/HfO<SUB>2</SUB> (0.6/2nm) bi-layer stack by ALD. The fabricated device with L<SUB>g</SUB>=4μm exhibits a record maximum transconductance (g<SUB>m_max</SUB>) in excess of 520μS/μm at >1μm region, and reasonably good electrostatic integrity, such as SS=110mV/decade and DIBL=43mV/V. Also, we have investigated the gate length scaling behavior in terms of output, transconductance, and transfer characteristics. In particular, our devices feature very uniform values of the electrostatic integrity, such as SS=100-110mV/decade, V<SUB>T</SUB>=-0.25V to -0.2V and DIBL=40-50mV/V, as L<SUB>g</SUB> decreases from 10μm to 4μm. Furthermore, we have explored the impact of source resistance (R<SUB>S</SUB>) onto the device characteristics of the InGaAs QW MOSFETs. In doing so, we have modeled both measured extrinsic transconductance (g<SUB>m_ext</SUB>) and intrinsic transconductance (g<SUB>m_int</SUB>) as a function of L<SUB>g</SUB>.

Salmonella Typhi, Salmonella Typhimurium 및 Salmonella Enteritidis의 항균제 감수성 (1997)

신영학,유정식,김기상,정동준,오경수,이점규,이상원,이근영,박미선,이복권,김호훈 국립보건연구원 1998 국립보건원보 Vol.35 No.-

性因傳播疾患 病原體에 대한 免疫學的 硏究 : 淋菌株의 抗原性및 藥劑耐性 遺傳子에 關한 硏究 Studies on the Antigenicity and Drug resistance gene of N. gonorrhoeae

辛光勳,金鎬薰,李馥權,金順南,申永鶴,姜鍊浩,張泳美,宋淇俊,廉? 국립보건연구원 1989 국립보건원보 Vol.26 No.