PDZ Domain-containing 1 (PDZK1) Protein Regulates Phospholipase C-β3 (PLC-β3)-specific Activation of Somatostatin by Forming a Ternary Complex with PLC-β3 and Somatostatin Receptors

Kim, Jung Kuk,Kwon, Ohman,Kim, Jinho,Kim, Eung-Kyun,Park, Hye Kyung,Lee, Ji Eun,Kim, Kyung Lock,Choi, Jung Woong,Lim, Seyoung,Seok, Heon,Lee-Kwon, Whaseon,Choi, Jang Hyun,Kang, Byoung Heon,Kim, Sanguk American Society for Biochemistry and Molecular Bi 2012 The Journal of biological chemistry Vol.287 No.25

Direct Profiling the Post-Translational Modification Codes of a Single Protein Immobilized on a Surface Using Cu-free Click Chemistry

Kim, Kyung Lock,Park, Kyeng Min,Murray, James,Kim, Kimoon,Ryu, Sung Ho American Chemical Society 2018 ACS central science Vol.4 No.5

<▼1><P/><P>Combinatorial post-translational modifications (PTMs), which can serve as dynamic “molecular barcodes”, have been proposed to regulate distinct protein functions. However, studies of combinatorial PTMs on single protein molecules have been hindered by a lack of suitable analytical methods. Here, we describe erasable single-molecule blotting (eSiMBlot) for combinatorial PTM profiling. This assay is performed in a highly multiplexed manner and leverages the benefits of covalent protein immobilization, cyclic probing with different antibodies, and single molecule fluorescence imaging. Especially, facile and efficient covalent immobilization on a surface using Cu-free click chemistry permits multiple rounds (>10) of antibody erasing/reprobing without loss of antigenicity. Moreover, cumulative detection of coregistered multiple data sets for immobilized single-epitope molecules, such as HA peptide, can be used to increase the antibody detection rate. Finally, eSiMBlot enables direct visualization and quantitative profiling of combinatorial PTM codes at the single-molecule level, as we demonstrate by revealing the novel phospho-codes of ligand-induced epidermal growth factor receptor. Thus, eSiMBlot provides an unprecedentedly simple, rapid, and versatile platform for analyzing the vast number of combinatorial PTMs in biological pathways.</P></▼1><▼2><P>An <U>e</U>rasable <U>si</U>ngle <U>m</U>olecule <U>blot</U> (eSiMBlot) assay provides an unprecedentedly simple and versatile platform for analyzing the combinatorial post-translational modifications in biological pathways.</P></▼2>

내시경으로 확진된 위선암의 VATER 팽대부 림프선 전이 1 예

김영호,김경호,김남훈,김규식,김진범,김배영,이영록,추무엽,황교승,곽재영,이명기,조연회,이주택 대한내과학회 1997 대한내과학회지 Vol.53 No.4

Cancer of the stomach is responsible for approximately 650,000 deaths globally each year and is probably second only to lung cancer worldwide as an overall cause of cancer-related mortality. Similar to the situation with most adenocarcinomas of the gastointestinal tract, carcinomas of the stomach can spread by local extension to adjacent normal structures and can develop lymphatic, peritoneal, and distant metastases. The tumor cells, can also permeate diffusely into the lymphatic plexus of the bowel, more often at the level of the upper duodenum hut sometimes down into the distal ileum and the large bowel. We report a case of lymphatic metastasis of gastric adenocarcinoma to the ampulla of Vater with review of the literature.

Surface-Enhanced RamanScattering of 4-Aminobenzenethiolon Ag and Au: pH Dependence of <i>b</i>₂-TypeBands

Kim, Kwan,Kim, Kyung Lock,Shin, Dongha,Choi, Jeong-Yong,Shin, Kuan Soo AmericanChemical Society 2012 JOURNAL OF PHYSICAL CHEMISTRY C - Vol.116 No.7

<P>The surface-enhanced Raman scattering (SERS) of 4-aminobenzenehtiol (4-ABT) has seen a surge of interest recently, since its SERS spectral features are dependent not only on the kinds of SERS substrates but also on the measurement conditions. The most unusual SERS feature is the appearance of b(2)-type bands in the region 1100-1500 cm(-1), in contrast to their absence in the normal Raman spectrum, but their origin is not yet clarified. However, propositions have been made suggesting that their appearance is associated with either a charge transfer phenomenon or a surface-induced photoreaction product such as 4,4'-dimercaptoazobenzene (4,4'-DMAB). In this work, we found that the b(2)-type bands of 4-ABT are strongly affected also by the solution pH. Regardless of the excitation wavelength and kind of SERS substrates, the b(2)-type bands appeared very weakly or negligibly at acidic pHs, while they were observed very distinctly at basic pHs. For the case of 4,4'-DMAB, any such pH dependence was not observed at all in its SERS spectra. Since the pH dependence in the SERS of 4-ABT was observed reversibly, the appearance and disappearance of the b(2)-type bands must have nothing to do with formation of any surface-induced photoreaction product like 4,4'-DMAB. Consulting the pH-dependent UV-vis absorption spectra and ab initio quantum mechanical calculation, the disappearance of the b(2)-type bands at acidic pHs is presumed to be associated with the upshift of the lowest unoccupied molecular orbital level of 4-ABT caused by protonation of the amine group: the charge transfer resonance chemical enhancement will then be less likely to occur.</P>

Surface-enhanced Raman scattering of 4,4′-dimercaptoazobenzene trapped in Au nanogaps

Kim, Kwan,Shin, Dongha,Kim, Kyung Lock,Shin, Kuan Soo The Royal Society of Chemistry 2012 Physical chemistry chemical physics Vol.14 No.12

<P>The surface-enhanced Raman scattering (SERS) of 4,4′-dimercaptoazobenzene (4,4′-DMAB), an alpha, omega-dithiol possessing also an azo moiety, has seen a surge of interest recently, since 4,4′-DMAB might be able to form from 4-aminobenzenethiol (4-ABT) <I>via</I> a surface-induced photoreaction. An understanding of the intrinsic SERS characteristics of 4,4′-DMAB is thus very important to evaluate the possibility of such a photoreaction. We found in this work that 4,4′-DMAB should adsorb on a flame-annealed Au substrate <I>via</I> one of its two thiol groups such that Au nanoparticles could adsorb further on the pendent thiol group, forming a SERS hot site. The most distinctive feature in the SERS of 4,4′-DMAB was the appearance of <I>a</I><SUB><I>g</I></SUB> bands, which were quite similar to the <I>b</I><SUB>2</SUB>-type bands occurring in the SERS of 4-ABT. In an electrochemical environment, the <I>a</I><SUB><I>g</I></SUB> bands of 4,4′-DMAB at 1431, 1387, and 1138 cm<SUP>−1</SUP> became weakened at lower potentials, completely disappearing at −1.0 V, but the bands were restored upon increasing the electrode potential, implying that neither electro- nor photo-chemical reaction to break the azo group took place, in agreement with data from a cyclic voltammogram. The appearance and disappearance of these <I>a</I><SUB><I>g</I></SUB> bands are thus concluded to be associated with the charge transfer phenomenon: 4,4′-DMAB must then be one of a unique group of compounds exhibiting chemical enhancement when subjected to a SERS environment.</P> <P>Graphic Abstract</P><P>We thoroughly examined the surface-enhanced Raman scattering characteristics of 4,4′-dimercaptoazobenzene trapped in an Au nanogap electrode, comparing with those of 4-aminobenzenethiol. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cp24135h'> </P>

Electromagnetic field enhancement in the gap between two Au nanoparticles: the size of hot site probed by surface-enhanced Raman scattering

Kim, Kwan,Shin, Dongha,Kim, Kyung Lock,Shin, Kuan Soo Royal Society of Chemistry 2010 Physical chemistry chemical physics Vol.12 No.15

<P>We have estimated the apparent size of the ‘hot’ site for surface-enhanced Raman scattering (SERS) located within the gap between two spherical Au nanoparticles. Initially, 55-nm sized Au nanoparticles are laid on a thiol-group terminated silane film, and then 1,4-phenylenediisocyanide (1,4-PDI) molecules are self-assembled onto the Au nanoparticles. 1,4-PDI is bonded to Au by forming one Au–CN bond, with another isocyanide group being pendent with respect to the Au surface. Up to this point, no Raman scattering is detected at all for 1,4-PDI. Upon attaching new Au nanoparticles onto the pendent isocyanide groups of 1,4-PDI, a Raman signal is distinctly observed. In agreement with the finite-difference time-domain (FDTD) calculation, this is understood in terms of the electromagnetic hot sites formed at the gaps between two Au nanoparticles. The Raman signal does not increase further, however, even after the adsorption of additional 1,4-PDI onto the vacant surfaces of the second Au nanoparticles. To a rough estimate, about 400 molecules residing only within a 10-nm diameter area of the center of the gap, adsorbed in the first stage, are then conjectured to have contributed most of the measured Raman signal of 1,4-PDI. This apparently indicates that the size of ‘hot’ site is very limited.</P> <P>Graphic Abstract</P><P>The molecules residing the center of the gap contribute most of the measured Raman signal of the molecule. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b917543a'> </P>

Surface-Enhanced Raman Scattering of 4-Aminobenzenethiol in Nanogaps between a Planar Ag Substrate and Pt Nanoparticles

Kim, Kwan,Lee, Hyang Bong,Choi, Jeong-Yong,Kim, Kyung Lock,Shin, Kuan Soo American Chemical Society 2011 The Journal of Physical Chemistry Part C Vol.115 No.27

<P>To determine how effectively transition metal nanoparticles can couple with a noble metal substrate to induce higher electromagnetic fields, we examined the surface-enhanced Raman scattering (SERS) characteristics of 4-aminobenzenethiol (4-ABT) positioned in the gaps formed by a flat Ag substrate and 20–150 nm Pt nanoparticles. Initially, no Raman peaks of 4-ABT could be identified when 4-ABT was self-assembled on a polished flat Ag substrate; however, Raman peaks could be seen by attaching Pt nanoparticles onto the pendent amine groups. Conversely, a higher Raman signal was observed when larger Pt nanoparticles were attached onto 4-ABT, regardless of the excitation wavelength. Moreover, a higher Raman signal was measured in response to excitation at 488 nm, followed by excitation at 514.5, 568, and 632.8 nm. Very similar size and excitation wavelength dependences were found from the 3-dimensional finite-difference time-domain simulation. Accordingly, the highest enhancement was achieved using ∼150 nm Pt particles at 488 nm excitation with an enhancement factor (EF) of 3.5 × 10<SUP>4</SUP> per Pt particle. However, the electromagnetic field enhancement observed was not in conformity with the UV/vis absorbance of ∼150 nm Pt nanoparticles, which suggested that higher EFs would be measured in the order of excitations at 632.8 > 568 > 514.5 > 488 nm. This discrepancy was attributed to the structure of Pt nanoparticles in that the 150 nm Pt particles were actually composed of 7 nm seed particles; thus, the electromagnetic interactions of individual Pt seed particles with the underlying Ag substrate occurred collectively, being more effective at shorter excitation wavelengths.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2011/jpccck.2011.115.issue-27/jp203263e/production/images/medium/jp-2011-03263e_0004.gif'></P>

Effect of volatile organic chemicals on surface-enhanced Raman scattering of 4-aminobenzenethiol on Ag: comparison with the potential dependence

Kim, Kwan,Kim, Kyung Lock,Choi, Jeong-Young,Shin, Dongha,Shin, Kuan Soo Royal Society of Chemistry 2011 Physical chemistry chemical physics Vol.13 No.34

<P>4-Aminobenzenethiol (4-ABT) is an unusual molecule in the sense that several distinct peaks whose counterparts are rarely found in the normal Raman spectrum are observed in its surface-enhanced Raman scattering (SERS) spectra. Their origin has been argued over recently as due to either a metal-to-adsorbate charge transfer or the formation of a photoreaction product such as dimercaptoazobenzene (DMAB). In an electrochemical SERS measurement, the intensities of the new peaks depended strongly not only on the excitation wavelength but also on the electrode potential. Interestingly, we observed a similar spectral variation even under ambient conditions by exposure of 4-ABT on Ag to volatile organic chemicals (VOCs) such as acetone and ammonia. Since acetone and ammonia barely react directly with 4-ABT, the effect of VOCs must be indirect, presumably associated with the movement of electrons between VOCs and the Ag substrate causing either an increase or a decrease in the surface potential of Ag. Based on the potential-dependent SERS data, the effect of acetone therefore appeared to correspond to an application of +0.15 V to the Ag substrate <I>vs</I>. a saturated Ag/AgCl electrode, while the effect of ammonia corresponded to the application of −0.45 V to Ag. We admit that much the same VOC effect could be observable if a photoproduct was formed immediately upon irradiation and the product was also subjected to a chemical enhancement mechanism. The Gaussian response of the peak intensities of the b<SUB>2</SUB>-type bands to applied potential, as well as to VOCs, dictated that the new peaks appearing in the SERS of 4-ABT have nothing to do with any electrochemical reaction. In addition, a separate preliminary work suggested that the b<SUB>2</SUB>-type bands are not at least due to a photoreaction product such as DMAB.</P> <P>Graphic Abstract</P><P>The Raman peak intensity of 4-aminobenzenethiol on Ag was found to be very susceptible not only to the excitation wavelength applied but also to the kind of volatile organic chemicals to which the Ag films were exposed. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c1cp21249d'> </P>

Effect of polar organic vapors on surface potential of Au nanoparticle aggregates probed by surface-enhanced Raman scattering of 2,6-dimethylphenylisocyanide

Kim, Kwan,Kim, Kyung Lock,Shin, Dongha,Lee, Ji Won,Shin, Kuan Soo Royal Society of Chemistry 2010 Chemical communications Vol.46 No.21

<P>We demonstrate by means of surface-enhanced Raman scattering of 2,6-dimethylphenylisocyanide that the surface potential of Au nanoparticle aggregates changes upon contact with polar organic vapors such as acetone and ammonia by as much as +0.16 and −0.56 V, respectively.</P> <P>Graphic Abstract</P><P>We demonstrate by means of surface-enhanced Raman scattering that the surface potential of Au nanoparticle aggregates changes upon contact with polar organic vapors such as acetone and ammonia by as much as +0.16 and –0.56 V, respectively. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b927587h'> </P>

Similarity and Dissimilarity in Surface-Enhanced Raman Scattering of 4-Aminobenzenethiol, 4,4′-Dimercaptoazobenzene, and 4,4′-Dimercaptohydrazobenzene on Ag

Kim, Kwan,Kim, Kyung Lock,Lee, Hyang Bong,Shin, Kuan Soo American Chemical Society 2012 JOURNAL OF PHYSICAL CHEMISTRY C - Vol.116 No.21

<P>There has been a surge of interest in the surface-enhanced Raman scattering (SERS) of 4-aminobenzenethiol (4-ABT) and 4,4′-dimercaptoazobenzene (4,4′-DMAB), since 4,4′-DMAB might be capable of being produced from 4-ABT via a surface-induced photoreaction. A problem was initially encountered in the interpretation of the SERS spectrum of 4-ABT due to difficulty in correlating several peaks therein with the normal Raman peaks, as the SERS spectral pattern of 4-ABT looked similar to that of 4,4′-DMAB. To clarify the issue, we have carefully examined the similarities and dissimilarities in the SERS of 4-ABT and 4,4′-DMAB, along with the SERS spectrum of their analogue molecule 4,4′-dimercaptohydrazobenzene (4,4′-DMHAB). Under ambient conditions, the SERS spectra of 4-ABT, 4,4′-DMAB, and 4,4′-DMHAB on Ag looked in fact comparable to one another, but the excitation wavelength dependence of the peak intensities dictated that the similarity in the SERS spectral patterns could not guarantee the photoconversion of the three molecules. On the other hand, the spectral dissimilarity was evidenced not only from the SERS spectra taken after treating the probing substrates with a borohydride solution but also from the potential-dependent SERS spectra. An electrochemical reaction did not take place for 4-ABT and 4,4′-DMHAB on Ag either by placing the substrates in contact with a borohydride solution or by lowering the electrode potential down to −1.2 V versus a saturated Ag/AgCl electrode. Conversely, however, 4,4′-DMAB on Ag was converted to 4-ABT not only by contact with a 100 mM borohydride but also by lowering the potential below −1.0 V. The reverse reaction from 4-ABT on Ag to 4,4′-DMAB appeared to be insignificant electrochemically as well as photochemically. All of these results clearly support our previous proposition that the b<SUB>2</SUB>-type bands appearing in the SERS of 4-ABT must be attributable to the chemical enhancement of 4-ABT itself.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2012/jpccck.2012.116.issue-21/jp303378p/production/images/medium/jp-2012-03378p_0009.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp303378p'>ACS Electronic Supporting Info</A></P>