Research Highlight

Atachment
첨부 '2'
Extra Form
author Sang-Hee Shim and Minhaeng Cho
journal Chemical Science (DOI: 10.1039/c8sc03558j)
Homepage https://cmsd.ibs.re.kr/html/cmsd_en/
?

단축키

Prev이전 문서

Next다음 문서

크게 작게 위로 아래로 댓글로 가기 인쇄
?

단축키

Prev이전 문서

Next다음 문서

크게 작게 위로 아래로 댓글로 가기 인쇄


이의현.jpg

Euihyun Lee(이의현, 박사과정, 제1저자)



Fluorescent proteins contain an internal chromophore constituted of amino acids or an external chromophore covalently bonded to the protein. To increase their fluorescence intensities, many research groups have attempted to mutate amino acids within or near the chromophore. Recently, a new type of fluorescent protein, called UnaG, in which the ligand binds to the protein through many noncovalent interactions was discovered. Later, a series of mutants of the UnaG protein were introduced, which include eUnaG with valine 2 mutated to leucine emitting significantly stronger fluorescence than the wild type and V2T mutant, in which valine 2 is mutated to threonine, emitting weaker fluorescence than the wild type. Interestingly, the single mutation sites of both eUnaG and V2T mutants are distant from the fluorophore, bilirubin, which renders the mechanism of such fluorescence enhancement or reduction unclear. To elucidate the origin of fluorescence intensity changes induced by the single mutations, we carried out extensive analyses on MD simulations for the original UnaG, eUnaG and V2T, and found that the bilirubin ligand bound to eUnaG is conformationally more rigid than the wild-type, particularly in the skeletal dihedral angles, possibly resulting in the increase of quantum yield through a reduction of non-radiative decay. On the other hand, the bilirubin bound to the V2T appears to be flexible than that in the UnaG. Furthermore, examining the structural correlations between the ligand and proteins, we found evidence that the bilirubin ligand is encapsulated in different environments composed of protein residues and water molecules that increase or decrease the stability of the ligand. The changed protein stability affects the mobility and confinement of water molecules captured between bilirubin and the protein. Since the flexible ligand contains multiple hydrogen bond (H-bond) donors and acceptors, the H-bonding structure and dynamics of bound water molecules are highly correlated with the rigidity of the bound ligand. Our results suggest that, to understand the fluorescence properties of protein mutants, especially the ones with noncovalently bound fluorophores with internal rotations, the interaction network among protein residues, ligand, and water molecules within the binding cavity should be investigated rather than focusing on the local structure near the fluorescing moiety. Our in-depth simulation study may offer a foundation for the design principles for engineering this new class of fluorescent proteins.


eulee.jpg



This article is part of the themed collection: 2018 Chemical Science HOT Article Collection


https://pubs.rsc.org/en/Content/ArticleLanding/2018/SC/C8SC03558J#!divAbstract




  1. Fine-tuning of wettability in a single metal–organic framework via postcoordination modification and its reduced graphene oxide aerogel for oil–water separation

    Sunhwi Eom(제1저자) Elaborate control of wettability in a single platform is essential for materials’ applications towards oil–water separation, but it still remains challenging. Herein, we performed postcoordination modification of Mg2(dob...
    Read More
  2. Harnessing Intramolecular Rotation to Enhance Two‐photon Imaging of Aβ Plaques Through Minimizing Background Fluorescence

    Jinwoo Shin(제1저자 석박통합과정) The aggregation of Aβ‐proteins in senile plaques is a critical event during the development of Alzheimer’s disease, and the postmortem detection of Aβ‐rich proteinaceous deposits via fluorescent staining re...
    Read More
  3. Proteogenomic Characterization of Human Early-Onset Gastric Cancer

    Dong-Gi Mun(제1저자, 박사과정) We report proteogenomic analysis of diffuse gastric cancers (GCs) in young populations. Phosphoproteome data elucidated signaling pathways associated with somatic mutations based on mutation-phosphorylation co...
    Read More
  4. Chemiluminescent Probe for the In Vitro and In Vivo Imaging of Cancers Over-Expressing NQO1

    Activatable (turn-on) probes that permit the rapid, sensitive, selective, and accurate identification of cancer-associated biomarkers can help drive advances in cancer research. Herein, a NAD(P)H:quinone oxidoreductase- 1 (NQO1)-specific ch...
    Read More
  5. Molecularly Controlled Stark Effect Induces Significant Rectification in Polycyclic Aromatic Hydrocarbon-terminated n-Alkanethiolates

    Soo Jin Cho(제1저자, 석박통합과정) Gyu Don Kong(공동 제1저자, 박사과정) Variation of electronic structure of individual molecules as a function of applied bias matters for performance of molecular and organic electronic devices. Understandi...
    Read More
  6. A New Approach for Large-Area Thermoelectric Junctions with Liquid Eutectic Gallium-Indium Electrode

    Sohyun Park(박소현, 통합과정, 제1저자) A challenge in organic thermoelectrics is to relate thermoelectric performance of devices to the chemical and electronic structures of organic component inside them on a molecular scale. To this end, a...
    Read More
  7. Nanometric Water Channels in Water-in-Salt Lithium Ion Battery Electrolyte

    Joonhyung Lim(임준형, 박사과정, 제1저자) Lithium-ion batteries (LIBs) have been deployed in a wide range of energy-storage applications and helped to revolutionize technological development. Recently, a lithium ion battery that uses superco...
    Read More
  8. Topotactic Transformations in an Icosahedral Nanocrystal to Form Efficient Water-Splitting Catalysts

    Designing high‐performance, precious‐metal‐based, and economic electrocatalysts remains an important challenge in proton exchange membrane (PEM) electrolyzers. Here, a highly active and durable bifunctional electrocatalyst for PEM electroly...
    Read More
  9. Fluorescence enhancement of a ligand-activated fluorescent protein induced by collective noncovalent interactions

    Euihyun Lee(이의현, 박사과정, 제1저자) Fluorescent proteins contain an internal chromophore constituted of amino acids or an external chromophore covalently bonded to the protein. To increase their fluorescence intensities, many research gr...
    Read More
  10. Elucidating the Role of Molecule-Electrode Interfacial Defects in Charge Tunneling Characteristics of Large-area Junctions

    Gyu Don Kong(공규돈, 박사과정, 제1저자) / Junji Jin(김준길, 석사과정, 제2저자) Interfacial chemistry at organic-inorganic contact critically determines function of a wide range of molecular and organic electronic devices and other systems. ...
    Read More
  11. PDMS-Coated Hypercrosslinked Porous Organic Polymers Modified via Double Postsynthetic Acidifications for Ammonia Capture

    Dong Won Kang(강동원, 통합과정, 제1저자) / Minjung Kang(강민정, 통합과정, 제2저자) A hypercrosslinked porous organic polymer was modified by post-oxidation and post-sulfonation to obtain a porous platform with high density of acidic groups....
    Read More
  12. Accurate Quantification of N-glycolylneuraminic Acid in Therapeutic Proteins Using Supramolecular Mass Spectrometry

    Hyun Hee L. Lee (이현희, 박사과정, 제1저자) / Chae Eun Heo (허채은, 박사과정, 제 2저자) Practical applications of innovative host-guest systems are challenging because of unexpected guest competitors and/or subtle environmental differences....
    Read More
  13. Overcoming Drug Resistance by Targeting Cancer Bioenergetics with an Activatable Prodrug

    Nearly without exception, all known cancer chemotherapeutics elicit a resistance response over time. The resulting resistance is correlated with poor clinical outcomes. Here we report a new approach to overcoming resistance that involves rep...
    Read More
  14. Janus Nanoparticle Structural Motif Control via Asymmetric Cation Exchange in Edge-Protected Cu1.81S@IrxSy Hexagonal Nanoplates

    Post-synthetic transformation of nanoparticles has received great attention, because this approach can provide an unusual route to elaborately composition-controlled nanostructures while maintaining the overall structure of the template. In...
    Read More
  15. Deconvolution of Tunneling Current in Large-area Junctions Formed with Mixed Self-Assembled Monolayers

    Junji Jin(석사과정) Gyu Don Kong(박사과정) Whereas single-component self-assembled monolayers (SAMs) have served widely as organic components in molecular and organic electronics, how the performance of the device is influenced by the hetero...
    Read More
  16. Electron heating and thermal relaxation of gold nanorods revealed by two-dimensional electronic spectroscopy

    To elucidate the complex interplay between the size and shape of gold nanorods and their electronic, photothermal, and optical properties for molecular imaging, photothermal therapy, and optoelectronic devices, it is a prerequisite to charac...
    Read More
  17. (Semi)ladder-Type Bithiophene Imide-Based All-Acceptor Semiconductors: Synthesis, Structure–Property Correlations, and Unipolar n-Type Transistor Performance

    Development of high-performance unipolar n-type organic semiconductors still remains as a great challenge. In this work, all-acceptor bithiophene imide-based ladder-type small molecules BTIn and semiladder-type homopolymers PBTIn (n = 1–5) w...
    Read More
  18. Dendrite-Embedded Platinum–Nickel Multiframes as Highly Active and Durable Electrocatalyst toward the Oxygen Reduction Reaction

    Hyukbu Kwon(석사과정) Jongsik Park(박사과정) Pt-based nanoframe catalysts have been explored extensively due to their superior activity toward the oxygen reduction reaction (ORR). Herein, we report the synthesis of Pt–Ni multiframes, which ...
    Read More
  19. Mid-Infrared Intraband Transition of Metal Excess Colloidal Ag2Se Nanocrystals

    Mihyeon Park(석사과정) Dongsun Choi(박사과정) Steady-state intraband transition, which is a promising electronic transition of a colloidal quantum dot along with the band-gap transition, had been a long-standing challenge. The steady-state ...
    Read More
  20. Enhanced Electron Transfer Mediated by Conjugated Polyelectrolyte and Its Application to Washing-Free DNA Detection

    Ji-Eun Jeong (박사과정) Direct electron transfer between a redox label and an electrode requires a very short working distance (<1-2 nm), and in general an affinity biosensor based on the direct electron transfer requires a finely smoothed ...
    Read More
Board Pagination Prev 1 2 3 4 5 6 7 Next
/ 7