1
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Cheung TL, Ju Z, Zhang W, Parker D, Deng R. Mechanistic Investigation of Sensitized Europium Luminescence: Excited State Dynamics and Luminescence Lifetime Thermometry. ACS APPLIED MATERIALS & INTERFACES 2024; 16:43933-43941. [PMID: 39135499 DOI: 10.1021/acsami.4c06899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/23/2024]
Abstract
Fluorescent nanothermometers based on thermal-dependent lifetime have a significant advantage in biological imaging owing to their immunity toward scattering, absorption, and autofluorescence. In this study, we present the first example of a water-soluble europium complex ([L1Eu]-) that exhibits high sensitivity (1.2% K-1 at 298 K) based on a temperature-dependent lifetime in the millisecond time range. This complex and its analogues show considerable potential for organelle imaging. The mechanism behind this thermal-sensitive behavior has been extensively investigated using transient absorption spectroscopy and variable temperature time-resolved luminescence methods. A highly efficient ligand sensitization process and a thermally activated back energy transfer process have been demonstrated. This study bridges the gap in small molecule thermometers with lifetimes longer than 1 ms and provides guidance in ligand design for metal coordination complex thermometers.
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Affiliation(s)
- Tsz Lam Cheung
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong 999077, China
| | - Zhijie Ju
- State Key Laboratory of Silicon and Advanced Semiconductor Materials, Institute for Composites Science Innovation, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310058, China
| | - Wenchao Zhang
- State Key Laboratory of Silicon and Advanced Semiconductor Materials, Institute for Composites Science Innovation, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310058, China
| | - David Parker
- Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong 999077, China
| | - Renren Deng
- State Key Laboratory of Silicon and Advanced Semiconductor Materials, Institute for Composites Science Innovation, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310058, China
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2
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Topping L, Welegedara AP, Judd M, Abdelkader EH, Cox N, Otting G, Butler SJ. A lanthanide tag for a complementary set of pseudocontact shifts. Chem Commun (Camb) 2024; 60:8458-8461. [PMID: 39040014 DOI: 10.1039/d4cc03007a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
Pseudocontact shifts (PCS) generated by paramagnetic lanthanide ions deliver powerful restraints for protein structure analysis by NMR spectroscopy. We present a new lanthanide tag that generates different PCSs than that of a related tag, which differs in structure by a single oxygen atom. It is highly reactive towards cysteine and performs well in turn-on luminescence and in EPR spectroscopy.
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Affiliation(s)
- Lydia Topping
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
| | - Adarshi P Welegedara
- ARC Centre of Excellence for Innovations in Peptide & Protein Science, Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Martyna Judd
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Elwy H Abdelkader
- ARC Centre of Excellence for Innovations in Peptide & Protein Science, Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Nicholas Cox
- Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Gottfried Otting
- ARC Centre of Excellence for Innovations in Peptide & Protein Science, Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Stephen J Butler
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
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3
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Ahmed T, Chakraborty A, Paul A, Baitalik S. Synthesis, characterization, luminescence properties and deciphering the role of a terpyridyl-imidazole based ligand in the dissimilar luminescence sensitization of ternary lanthanide(III) tris-(β-diketonate) complexes. Dalton Trans 2023; 52:14027-14038. [PMID: 37740376 DOI: 10.1039/d3dt01701j] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/24/2023]
Abstract
We designed four ternary lanthanide tris-(β-diketonate) complexes of the form [Ln(tta)3(tpy-HImzphen)], where Ln = LaIII, EuIII, SmIII and TbIII; tta = (2-theonyltrifluoroacetonate) and tpy-HImzphen = 2-(4-[2,2':6',2'']terpyridin-4'-yl-phenyl)-1H-phenanthro[9,10-d]imidazole. All the complexes have been thoroughly characterized by standard analytical tools and spectroscopic techniques including single crystal X-ray diffraction. In situ generation of the complexes was also monitored via absorption and emission spectroscopy upon incremental addition of the respective lanthanide precursor {Ln(tta)3(H2O)2} to the dichloromethane solution of the terpyridyl-imidazole ligand. The photophysical behaviors of all the complexes were thoroughly investigated via absorption and both steady-state and time-resolved emission spectroscopic techniques. The emission spectral measurements were carried out at both room temperature and 77 K to understand the deactivation dynamics of the excited states and elucidate the distinctive luminescence responses from the four lanthanide metal ions owing to the introduction of the terpyridyl-based ancillary ligand.
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Affiliation(s)
- Toushique Ahmed
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Amit Chakraborty
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Animesh Paul
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
| | - Sujoy Baitalik
- Inorganic Chemistry Section, Department of Chemistry, Jadavpur University, Kolkata 700032, India.
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4
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Park Y, Taguchi A, Baidin V, Kahne D, Walker S. A Time-Resolved FRET Assay Identifies a Small Molecule that Inhibits the Essential Bacterial Cell Wall Polymerase FtsW. Angew Chem Int Ed Engl 2023; 62:e202301522. [PMID: 37099323 PMCID: PMC10330507 DOI: 10.1002/anie.202301522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/10/2023] [Accepted: 04/26/2023] [Indexed: 04/27/2023]
Abstract
The peptidoglycan cell wall is essential for bacterial survival. To form the cell wall, peptidoglycan glycosyltransferases (PGTs) polymerize Lipid II to make glycan strands and then those strands are crosslinked by transpeptidases (TPs). Recently, the SEDS (for shape, elongation, division, and sporulation) proteins were identified as a new class of PGTs. The SEDS protein FtsW, which produces septal peptidoglycan during cell division, is an attractive target for novel antibiotics because it is essential in virtually all bacteria. Here, we developed a time-resolved Förster resonance energy transfer (TR-FRET) assay to monitor PGT activity and screened a Staphylococcus aureus lethal compound library for FtsW inhibitors. We identified a compound that inhibits S. aureus FtsW in vitro. Using a non-polymerizable Lipid II derivative, we showed that this compound competes with Lipid II for binding to FtsW. The assays described here will be useful for discovering and characterizing other PGT inhibitors.
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Affiliation(s)
- Youngseon Park
- Department of Microbiology, Harvard Medical School, 4 Blackfan Circle, Boston, Massachusetts 02115, United States
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, Massachusetts 02138, United States
| | - Atsushi Taguchi
- Department of Microbiology, Harvard Medical School, 4 Blackfan Circle, Boston, Massachusetts 02115, United States
- (Current location) SANKEN (The Institute of Scientific and Industrial Research), Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka, 567-0047, Japan
| | - Vadim Baidin
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, Massachusetts 02138, United States
| | - Daniel Kahne
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, Massachusetts 02138, United States
| | - Suzanne Walker
- Department of Microbiology, Harvard Medical School, 4 Blackfan Circle, Boston, Massachusetts 02115, United States
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5
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Choi JH, Fremy G, Charnay T, Fayad N, Pécaut J, Erbek S, Hildebrandt N, Martel-Frachet V, Grichine A, Sénèque O. Luminescent Peptide/Lanthanide(III) Complex Conjugates with Push–Pull Antennas: Application to One- and Two-Photon Microscopy Imaging. Inorg Chem 2022; 61:20674-20689. [DOI: 10.1021/acs.inorgchem.2c03646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Ji-Hyung Choi
- Université Grenoble Alpes, CNRS, CEA, IRIG, LCBM (UMR 5249), Grenoble F-38000, France
| | - Guillaume Fremy
- Université Grenoble Alpes, CNRS, CEA, IRIG, LCBM (UMR 5249), Grenoble F-38000, France
- Université Grenoble Alpes, CNRS, DCM (UMR 5250), Grenoble F-38000, France
| | - Thibault Charnay
- Université Grenoble Alpes, CNRS, CEA, IRIG, LCBM (UMR 5249), Grenoble F-38000, France
| | - Nour Fayad
- Laboratoire COBRA (Chimie Organique, Bioorganique, Réactivite et Analyse), UMR 6014, CNRS, Université de Rouen Normandie, INSA, Mont-Saint-Aignan Cedex 76821, France
| | - Jacques Pécaut
- Université Grenoble Alpes, CEA, CNRS, IRIG, SyMMES, Grenoble F-38000, France
| | - Sule Erbek
- Institute for Advanced Biosciences, Université Grenoble Alpes, INSERM U1209, CNRS UMR 5309, Grenoble F-38000, France
- EPHE, PSL Research University, 4-14 Rue Ferrus, Paris 75014, France
| | - Niko Hildebrandt
- Laboratoire COBRA (Chimie Organique, Bioorganique, Réactivite et Analyse), UMR 6014, CNRS, Université de Rouen Normandie, INSA, Mont-Saint-Aignan Cedex 76821, France
| | - Véronique Martel-Frachet
- Institute for Advanced Biosciences, Université Grenoble Alpes, INSERM U1209, CNRS UMR 5309, Grenoble F-38000, France
- EPHE, PSL Research University, 4-14 Rue Ferrus, Paris 75014, France
| | - Alexei Grichine
- Institute for Advanced Biosciences, Université Grenoble Alpes, INSERM U1209, CNRS UMR 5309, Grenoble F-38000, France
| | - Olivier Sénèque
- Université Grenoble Alpes, CNRS, CEA, IRIG, LCBM (UMR 5249), Grenoble F-38000, France
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6
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Nanobody-based sensors reveal a high proportion of mGlu heterodimers in the brain. Nat Chem Biol 2022; 18:894-903. [PMID: 35681029 DOI: 10.1038/s41589-022-01050-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 04/29/2022] [Indexed: 11/08/2022]
Abstract
Membrane proteins, including ion channels, receptors and transporters, are often composed of multiple subunits and can form large complexes. Their specific composition in native tissues is difficult to determine and remains largely unknown. In this study, we developed a method for determining the subunit composition of endogenous cell surface protein complexes from isolated native tissues. Our method relies on nanobody-based sensors, which enable proximity detection between subunits in time-resolved Förster resonance energy transfer (FRET) measurements. Additionally, given conformation-specific nanobodies, the activation of these complexes can be recorded in native brain tissue. Applied to the metabotropic glutamate receptors in different brain regions, this approach revealed the clear existence of functional metabotropic glutamate (mGlu)2-mGlu4 heterodimers in addition to mGlu2 and mGlu4 homodimers. Strikingly, the mGlu4 subunits appear to be mainly heterodimers in the brain. Overall, these versatile biosensors can determine the presence and activity of endogenous membrane proteins in native tissues with high fidelity and convenience.
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7
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Parker D, Fradgley JD, Delbianco M, Starck M, Walton JW, Zwier JM. Comparative analysis of lanthanide excited state quenching by electronic energy and electron transfer processes. Faraday Discuss 2022; 234:159-174. [PMID: 35147141 DOI: 10.1039/d1fd00059d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The relative sensitivities of structurally related Eu(III) complexes to quenching by electron and energy transfer processes have been compared. In two sets of 9-coordinate complexes based on 1,4,7-triazacyclononane, the Eu emission lifetime decreased as the number of conjugated sensitising groups and the number of unbound ligand N atoms increased, consistent with photoinduced electron transfer to the excited Eu(III) ion that is suppressed by N-protonation. Quenching of the Eu 5D0 excited state may also occur by electronic energy transfer, and the quenching of a variety of 9-coordinate complexes by a cyanine dye with optimal spectral overlap occurs by an efficient FRET process, defined by a Förster radius (R0) value of 68 Å and characterised by second rate constants in the order of 109 M-1 s-1; these values were insensitive to changes in the ligand structure and to the overall complex hydrophilicity. Quenching of the Eu and Tb excited states by energy transfer to Mn(II) and Cu(II) aqua ions occurred over much shorter distances, with rate constants of around 106 M-1 s-1, owing to the much lower spectral overlap integral. The calculated R0 values were estimated to be between 2.5 to 4 Å in the former case, suggesting the presence of a Dexter energy transfer mechanism that requires much closer contact, consistent with the enhanced sensitivity of the rate of quenching to the degree of steric shielding of the lanthanide ion provided by the ligand.
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Affiliation(s)
- David Parker
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK. .,Department of Chemistry, Hong Kong Baptist University, Kowloon Tong, Hong Kong
| | - Jack D Fradgley
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK.
| | - Martina Delbianco
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK.
| | - Matthieu Starck
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK.
| | - James W Walton
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK.
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8
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Wheeler S, Breen C, Li Y, Hewitt SH, Robertson E, Yates EA, Barsukov IL, Fernig DG, Butler SJ. Anion binding to a cationic europium(III) probe enables the first real-time assay of heparan sulfotransferase activity. Org Biomol Chem 2022; 20:596-605. [PMID: 34951618 PMCID: PMC8767414 DOI: 10.1039/d1ob02071d] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 11/18/2021] [Indexed: 12/25/2022]
Abstract
Sulfotransferases constitute a ubiquitous class of enzymes which are poorly understood due to the lack of a convenient tool for screening their activity. These enzymes use the anion PAPS (adenosine-3'-phosphate-5'-phosphosulfate) as a donor for a broad range of acceptor substrates, including carbohydrates, producing sulfated compounds and PAP (adenosine-3',5'-diphosphate) as a side product. We present a europium(III)-based probe that binds reversibly to both PAPS and PAP, producing a larger luminescence enhancement with the latter anion. We exploit this greater emission enhancement with PAP to demonstrate the first direct real-time assay of a heparan sulfate sulfotransferase using a multi-well plate format. The selective response of our probe towards PAP over structurally similar nucleoside phosphate anions, and over other anions, is investigated and discussed. This work opens the possibility of investigating more fully the roles played by this enzyme class in health and disease, including operationally simple inhibitor screening.
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Affiliation(s)
- Simon Wheeler
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
| | - Colum Breen
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
| | - Yong Li
- Department of Biochemistry, Institute for Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Sarah H Hewitt
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
| | - Erin Robertson
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
| | - Edwin A Yates
- Department of Biochemistry, Institute for Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Igor L Barsukov
- Department of Biochemistry, Institute for Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - David G Fernig
- Department of Biochemistry, Institute for Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Stephen J Butler
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
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9
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Canisares FS, Mutti AM, Cavalcante DG, Job AE, Pires AM, Lima SA. Luminescence and cytotoxic study of red emissive europium(III) complex as a cell dye. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2021.113552] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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10
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Leygue N, Picard C, Faure P, Bourrier E, Lamarque L, Zwier JM, Galaup C. Design of novel tripyridinophane-based Eu(III) complexes as efficient luminescent labels for bioassay applications. Org Biomol Chem 2021; 20:182-195. [PMID: 34878481 DOI: 10.1039/d1ob02092g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In this work, the development of highly luminescent europium(III) complexes in water solution is reported, including their syntheses, analyses of their photophysical properties and applications in bioassays. Three Eu(III) complexes are derived from new ligands based on a tripyridinophane platform. There are four distinct sections in the structure of these ligands: an 18-membered polyaminocarboxylic macrocycle to bind efficiently lanthanide ions in aqueous solutions, three chromophoric subunits (4-(phenylethynyl)pyridine moieties) to effectively sensitize the emission of the metal, two peripheral moieties to solubilise the complex in aqueous media (sulfonate, sulfobetaine or glucose groups) and a free NH2 group available for grafting or bioconjugation. In our synthetic procedure, a pivotal macrocyclic platform is obtained with a high yield in the crucial macrocyclization step due to a metal template ion effect (74% yield). In Tris aqueous buffer (pH 7.4), the Eu(III) complexes show a maximum excitation wavelength at 320 nm, a suitable overall quantum yield (14%), a relatively long lifetime (0.80 ms) and a one-photon brightness in the range of 10 000 M-1 cm-1. Importantly, these photophysical properties are retained at dilute concentrations, even in the presence of a very large excess of potentially competing species, such as EDTA or Mg2+ ions. Furthermore, we report the bioconjugation of a Eu(III) complex labelled by an N-hydroxysuccinimide ester reactive group with an antibody (anti-glutathione-S-transferase) and the successful application of the corresponding antibody conjugate in the detection of GST-biotin in a fluoroimmunoassay. These new complexes provide a solution for high sensitivity in Homogeneous Time-Resolved Fluorescence (HTRF®) bioassays.
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Affiliation(s)
- Nadine Leygue
- SPCMIB, UMR5068 CNRS-Université Paul Sabatier-Toulouse III, 118 Route de Narbonne, F-31062 Toulouse, France.
| | - Claude Picard
- SPCMIB, UMR5068 CNRS-Université Paul Sabatier-Toulouse III, 118 Route de Narbonne, F-31062 Toulouse, France.
| | - Pamela Faure
- Cisbio Bioassays, BP 84175, 30200 Codolet, France.
| | | | | | | | - Chantal Galaup
- SPCMIB, UMR5068 CNRS-Université Paul Sabatier-Toulouse III, 118 Route de Narbonne, F-31062 Toulouse, France.
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11
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Yu W, Kim Y, Jang Y, Lee SM. Eu(III)-Chelated Polymeric Hybrid Nanoplatform for Luminescence Resonance Energy Transfer (LRET)-Based Real-Time Monitoring of Organic Cargo Release. ACS Macro Lett 2021; 10:1602-1608. [PMID: 35549142 DOI: 10.1021/acsmacrolett.1c00570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The real-time monitoring of specific guest release from nanoscale assemblies has been of great interest for the potential application in nanomedicine. Herein, we present a facile one-pot strategy to achieve a metal-chelated nanoscale platform that enables a highly efficient luminescence resonance energy transfer (LRET) for the monitoring of hydrophobic cargo release. To this end, Eu(III) as a lanthanide luminophore was employed to induce the metal-mediated self-assembly of chelating block copolymers in the presence of fluorescent Nile Blue (NB) as an organic cargo, which can then produce a nanoscale assembly containing a hybrid polyionic complex (HPIC) of Eu(III) and NB as LRET pairs. Exploiting this Eu(III)-chelated, NB-incorporated polymeric assembly as a luminescent platform that allows for the intermolecular distance-sensitive LRET, we further demonstrate that the facile monitoring of NB release from the carriers was made possible upon the addition of serum albumin as a protein reservoir for the released hydrophobic guest molecules.
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Affiliation(s)
- Wonjeong Yu
- Department of Chemistry, The Catholic University of Korea, Bucheon, Gyeonggi-do 14662, Korea
| | - Yeojin Kim
- Department of Chemistry, The Catholic University of Korea, Bucheon, Gyeonggi-do 14662, Korea
| | - Yoojin Jang
- Department of Chemistry, The Catholic University of Korea, Bucheon, Gyeonggi-do 14662, Korea
| | - Sang-Min Lee
- Department of Chemistry, The Catholic University of Korea, Bucheon, Gyeonggi-do 14662, Korea
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12
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Song Y, Deng X, Shi W, Tang F, Huang W, Gong L, Qin Q. A homogeneous time-resolved fluorometric energy transfer assay for the binding assessment of FcRn with IgG antibodies. J Immunol Methods 2021; 499:113180. [PMID: 34736962 DOI: 10.1016/j.jim.2021.113180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 10/22/2021] [Accepted: 10/26/2021] [Indexed: 11/28/2022]
Abstract
We aimed to develop a homogeneous time-resolved fluorometric energy transfer assay for assessment of human neonatal Fc receptor binding activity with IgG-type antibodies. The assay was configured with FcRn-coupled with Eu cryptate via biotin and streptavidin interaction as donor and IgG1 labeled with d2 as acceptor. Only a single incubation step was involved and no wash step was required. The assay demonstrated good accuracy, precision, linearity and specificity. Our further investigation with a rat pharmacokinetics study revealed that the terminal t1/2 for Trastuzumab and its related three ADCs agreed with the EC50 data. The assay can be applied to various IgGs with modifications to identify antibodies with appropriate binding ability to human FcRn.
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Affiliation(s)
- Yakai Song
- Department of Immunoassay and Immunochemistry, Center for Drug Safety Evaluation and Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Pudong, Shanghai 201203,China
| | - Xiaojie Deng
- Department of Immunoassay and Immunochemistry, Center for Drug Safety Evaluation and Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Pudong, Shanghai 201203,China
| | - Wei Shi
- CAS Key Laboratory of Receptor Research, CAS Center for Excellence in Molecular Cell Science, Center for Biotherapeutics Discovery Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Pudong, Shanghai 201203, China
| | - Feng Tang
- CAS Key Laboratory of Receptor Research, CAS Center for Excellence in Molecular Cell Science, Center for Biotherapeutics Discovery Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Pudong, Shanghai 201203, China
| | - Wei Huang
- CAS Key Laboratory of Receptor Research, CAS Center for Excellence in Molecular Cell Science, Center for Biotherapeutics Discovery Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Pudong, Shanghai 201203, China
| | - Likun Gong
- Department of Immunoassay and Immunochemistry, Center for Drug Safety Evaluation and Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Pudong, Shanghai 201203,China.
| | - Qiuping Qin
- Department of Immunoassay and Immunochemistry, Center for Drug Safety Evaluation and Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Pudong, Shanghai 201203,China.
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13
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Wu S, Galán LA, Roux M, Riobé F, Le Guennic B, Guyot Y, Le Bahers T, Micouin L, Maury O, Benedetti E. Tuning Excited-State Properties of [2.2]Paracyclophane-Based Antennas to Ensure Efficient Sensitization of Lanthanide Ions or Singlet Oxygen Generation. Inorg Chem 2021; 60:16194-16203. [PMID: 34637309 DOI: 10.1021/acs.inorgchem.1c01986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The multistep synthesis of original antennas incorporating substituted [2.2]paracyclophane (pCp) moieties in the π-conjugated skeleton is described. These antennas, functionalized with an electron donor alkoxy fragment (A1) or with a fused coumarin derivative (A2), are incorporated in a triazacyclonane macrocyclic ligand L1 or L2, respectively, for the design of Eu(III), Yb(III), and Gd(III) complexes. A combined photophysical/theoretical study reveals that A1 presents a charge transfer character via through-space paracyclophane conjugation, whereas A2 presents only local excited states centered on the coumarin-paracyclophane moiety, strongly favoring triplet state population via intersystem crossing. The resulting complexes EuL1 and YbL2 are fully emissive in red and near-infrared, respectively, whereas the GdL2 complex acts as a photosensitizer for the generation of singlet oxygen.
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Affiliation(s)
- Shiqi Wu
- Univ Paris, Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, 45 Rue des Saints Pères, 75006 Paris, France
| | - Laura Abad Galán
- Univ Lyon, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5182, Laboratoire de Chimie, Lyon F-69342, France
| | - Margaux Roux
- Univ Lyon, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5182, Laboratoire de Chimie, Lyon F-69342, France
| | - François Riobé
- Univ Lyon, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5182, Laboratoire de Chimie, Lyon F-69342, France
| | - Boris Le Guennic
- Univ Rennes, ISCR (Institut des Sciences Chimiques de Rennes), CNRS UMR 6226, F-35000 Rennes, France
| | - Yannick Guyot
- Univ Lyon, Institut Lumière Matière, Université Claude Bernard Lyon 1, CNRS UMR 5306, 10 Rue Ada Byron, 69622 Villeurbanne Cedex, France
| | - Tangui Le Bahers
- Univ Lyon, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5182, Laboratoire de Chimie, Lyon F-69342, France
| | - Laurent Micouin
- Univ Paris, Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, 45 Rue des Saints Pères, 75006 Paris, France
| | - Olivier Maury
- Univ Lyon, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5182, Laboratoire de Chimie, Lyon F-69342, France
| | - Erica Benedetti
- Univ Paris, Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR 8601, 45 Rue des Saints Pères, 75006 Paris, France
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14
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Herath ID, Breen C, Hewitt SH, Berki TR, Kassir AF, Dodson C, Judd M, Jabar S, Cox N, Otting G, Butler SJ. A Chiral Lanthanide Tag for Stable and Rigid Attachment to Single Cysteine Residues in Proteins for NMR, EPR and Time-Resolved Luminescence Studies. Chemistry 2021; 27:13009-13023. [PMID: 34152643 PMCID: PMC8518945 DOI: 10.1002/chem.202101143] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Indexed: 12/12/2022]
Abstract
A lanthanide-binding tag site-specifically attached to a protein presents a tool to probe the protein by multiple spectroscopic techniques, including nuclear magnetic resonance, electron paramagnetic resonance and time-resolved luminescence spectroscopy. Here a new stable chiral LnIII tag, referred to as C12, is presented for spontaneous and quantitative reaction with a cysteine residue to generate a stable thioether bond. The synthetic protocol of the tag is relatively straightforward, and the tag is stable for storage and shipping. It displays greatly enhanced reactivity towards selenocysteine, opening a route towards selective tagging of selenocysteine in proteins containing cysteine residues. Loaded with TbIII or TmIII ions, the C12 tag readily generates pseudocontact shifts (PCS) in protein NMR spectra. It produces a relatively rigid tether between lanthanide and protein, which is beneficial for interpretation of the PCSs by single magnetic susceptibility anisotropy tensors, and it is suitable for measuring distance distributions in double electron-electron resonance experiments. Upon reaction with cysteine or other thiol compounds, the TbIII complex exhibits a 100-fold enhancement in luminescence quantum yield, affording a highly sensitive turn-on luminescence probe for time-resolved FRET assays and enzyme reaction monitoring.
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Affiliation(s)
- Iresha D. Herath
- Research School of ChemistryThe Australian National UniversityCanberraACT 2605Australia
| | - Colum Breen
- Department of ChemistryLoughborough UniversityEpinal WayLoughboroughLE11 3TUUK
| | - Sarah H. Hewitt
- Department of ChemistryLoughborough UniversityEpinal WayLoughboroughLE11 3TUUK
| | - Thomas R. Berki
- Department of ChemistryLoughborough UniversityEpinal WayLoughboroughLE11 3TUUK
| | - Ahmad F. Kassir
- Department of ChemistryLoughborough UniversityEpinal WayLoughboroughLE11 3TUUK
| | - Charlotte Dodson
- Department of Pharmacy & PharmacologyUniversity of Bath Claverton DownBathBA2 7AYUK
| | - Martyna Judd
- Research School of ChemistryThe Australian National UniversityCanberraACT 2605Australia
| | - Shereen Jabar
- Research School of ChemistryThe Australian National UniversityCanberraACT 2605Australia
| | - Nicholas Cox
- Research School of ChemistryThe Australian National UniversityCanberraACT 2605Australia
| | - Gottfried Otting
- Research School of ChemistryThe Australian National UniversityCanberraACT 2605Australia
| | - Stephen J. Butler
- Department of ChemistryLoughborough UniversityEpinal WayLoughboroughLE11 3TUUK
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15
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Fradgley JD, Starck M, Laget M, Bourrier E, Dupuis E, Lamarque L, Trinquet E, Zwier JM, Parker D. Targeted pH switched europium complexes monitoring receptor internalisation in living cells. Chem Commun (Camb) 2021; 57:5814-5817. [PMID: 34002181 DOI: 10.1039/d1cc01029h] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
We report the design and evaluation of pH responsive luminescent europium(iii) probes that allow conjugation to targeting vectors to monitor receptor internalisation in cells. The approach adopted here can be used to tag proteins selectively and to monitor uptake into more acidic organelles, thereby enhancing the performance of time-resolved internalisation assays that require pH monitoring in real time.
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Affiliation(s)
- Jack D Fradgley
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, UK.
| | - Matthieu Starck
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, UK.
| | - Michel Laget
- Cisbio Bioassays, BP 84175, 30200 Codolet, France
| | | | | | | | | | | | - David Parker
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, UK.
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16
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Li Y, Wang J, Tian Y, Huang Z, Qian C, Duan Y. The development of a wash-free homogeneous immunoassay method for the detection of tetracycline in environmental samples. Analyst 2021; 146:4918-4926. [PMID: 34250990 DOI: 10.1039/d1an00929j] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Antibiotic residues have become the major source of environmental pollutants. In order to monitor tetracycline (TC) in the environment, we have established a highly sensitive and wash-free homogeneous time-resolved immunoassay. This analytical method was based on a rare earth chelate with excellent fluorescence properties. The cryptate organic ligand had good stability and acted as an antenna for Eu3+ excitation. In a homogeneous system, the Eu3+ cryptate complex was used as a label to bind to antibodies. Under the action of immunoaffinity, fluorescent donors and acceptors were close to each other, which induced the FRET effect to produce proportional fluorescence. Under the optimal parameters, the half-inhibitory concentration (IC50) and limit of detection (LOD, IC10) of TC were 0.4188 ng mL-1 and 0.0106 ng mL-1, respectively. The linear range (IC20-IC80) was 0.0273-9.2645 ng mL-1. With the environmental samples, the recovery rate of TC was 84.3-107.2%, and the standard deviation (RSD) was 4.6-12.9%. The results showed the good sensitivity and reliability of the method. Compared with the traditional ELISA, our method has less background interference, only one step was required without the washing procedure, and the detection result can be obtained by 30 min incubation, which improves the detection efficiency. Because of the characteristics of immunoassays, different pollutants can be monitored by changing the antibodies. This method provides an alternative path for detecting environmental pollutants and has the potential to develop into an on-site detection kit.
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Affiliation(s)
- Yinjun Li
- Research Center of Analytical Instrumentation, Northwest University, Xi'an, Shaanxi 710069, China. and Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an, Shaanxi 710069, China
| | - Jiayu Wang
- Research Center of Analytical Instrumentation, Northwest University, Xi'an, Shaanxi 710069, China. and Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an, Shaanxi 710069, China
| | - Yonghui Tian
- Research Center of Analytical Instrumentation, Northwest University, Xi'an, Shaanxi 710069, China. and Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an, Shaanxi 710069, China
| | - Zhijun Huang
- Research Center of Analytical Instrumentation, Northwest University, Xi'an, Shaanxi 710069, China. and Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an, Shaanxi 710069, China
| | - Cheng Qian
- Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, College of Urban and Environmental Sciences, Northwest University, Xi'an, 710127, China
| | - Yixiang Duan
- Research Center of Analytical Instrumentation, Northwest University, Xi'an, Shaanxi 710069, China. and Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry & Materials Science, Northwest University, Xi'an, Shaanxi 710069, China
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17
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Abad‐Galán L, Cieslik P, Comba P, Gast M, Maury O, Neupert L, Roux A, Wadepohl H. Excited State Properties of Lanthanide(III) Complexes with a Nonadentate Bispidine Ligand. Chemistry 2021; 27:10303-10312. [PMID: 33780569 PMCID: PMC8360039 DOI: 10.1002/chem.202005459] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Indexed: 12/03/2022]
Abstract
EuIII , TbIII , GdIII and YbIII complexes of the nonadentate bispidine derivative L2 (bispidine=3,7-diazabicyclo[3.3.1]nonane) were successfully synthesized and their emission properties studied. The X-ray crystallography reveals full encapsulation by the nonadentate ligand L2 that enforces to all LnIII cations a common highly symmetrical capped square antiprismatic (CSAPR) coordination geometry (pseudo C4v symmetry). The well-resolved identical emission spectra in solid state and in solution confirm equal structures in both media. As therefore expected, this results in long-lived excited states and high emission quantum yields ([EuIII L2 ]+ , H2 O, 298 K, τ=1.51 ms, ϕ=0.35; [TbIII L2 ]+ , H2 O, 298 K, τ=1.95 ms, ϕ=0.68). Together with the very high kinetic and thermodynamic stabilities, these complexes are a possible basis for interesting biological probes.
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Affiliation(s)
- Laura Abad‐Galán
- Université de LyonENS de LyonLaboratoire de ChimieCNRS UMR 5182Université Claude Bernard Lyon 169342LyonFrance
| | - Patrick Cieslik
- Universität HeidelbergAnorganisch-Chemisches InstitutINF 27069120HeidelbergGermany
| | - Peter Comba
- Universität HeidelbergAnorganisch-Chemisches InstitutINF 27069120HeidelbergGermany
- Universität HeidelbergInterdisciplinary Center for Scientific Computing69120HeidelbergGermany
| | - Michael Gast
- Universität HeidelbergAnorganisch-Chemisches InstitutINF 27069120HeidelbergGermany
| | - Olivier Maury
- Université de LyonENS de LyonLaboratoire de ChimieCNRS UMR 5182Université Claude Bernard Lyon 169342LyonFrance
| | - Lucca Neupert
- Universität HeidelbergAnorganisch-Chemisches InstitutINF 27069120HeidelbergGermany
| | - Amandine Roux
- Université de LyonENS de LyonLaboratoire de ChimieCNRS UMR 5182Université Claude Bernard Lyon 169342LyonFrance
| | - Hubert Wadepohl
- Universität HeidelbergAnorganisch-Chemisches InstitutINF 27069120HeidelbergGermany
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18
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Parker D, Fradgley JD, Wong KL. The design of responsive luminescent lanthanide probes and sensors. Chem Soc Rev 2021; 50:8193-8213. [PMID: 34075982 DOI: 10.1039/d1cs00310k] [Citation(s) in RCA: 110] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The principles of the design of responsive luminescent probes and sensors based on lanthanide emission are summarised, based on a mechanistic understanding of their mode of action. Competing kinetic pathways for deactivation of the excited states that occur are described, highlighting the need to consider each of the salient quenching processes. Such an analysis dictates the choice of both the ligand and its integral sensitising moiety for the particular application. The key aspects of quenching involving electron transfer and vibrational and electronic energy transfer are highlighted and exemplified. Responsive systems for pH, pM, pX and pO2 and selected biochemical analytes are distinguished, according to the nature of the optical signal observed. Signal changes include both simple and ratiometric intensity measurements, emission lifetime variations and the unique features associated with the observation of circularly polarised luminescence (CPL) for chiral systems. A classification of responsive lanthanide probes is introduced. Examples of the operation of probes for reactive oxygen species, citrate, bicarbonate, α1-AGP and pH are used to illustrate reversible and irreversible transformations of the ligand constitution, as well as the reversible changes to the metal primary and secondary coordination sphere that sensitively perturb the ligand field. Finally, systems that function by modulation of dynamic quenching of the ligand or metal excited states are described, including real time observation of endosomal acidification in living cells, rapid urate analysis in serum, accurate temperature assessment in confined compartments and high throughput screening of drug binding to G-protein coupled receptors.
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Affiliation(s)
- David Parker
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK.
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19
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Boltersdorf T, Gavins FNE, Long NJ. Long-lived lanthanide emission via a pH-sensitive and switchable LRET complex. Chem Sci 2021; 12:8740-8745. [PMID: 34257873 PMCID: PMC8246121 DOI: 10.1039/d1sc01503f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/15/2021] [Indexed: 12/17/2022] Open
Abstract
Lanthanide-based luminescence resonance energy transfer (LRET) can be used as a tool to enhance lanthanide emission for time-resolved cellular imaging applications. By shortening lanthanide emission lifetimes whilst providing an alternative radiative pathway to the formally forbidden, weak lanthanide-only emission, the photon flux of such systems is increased. With this aim in mind, we investigated energy transfer in differently spaced donor–acceptor terbium–rhodamine pairs with the LRET “on” (low pH) and LRET “off” (high pH). Results informed the design, preparation and characterisation of a compound containing terbium, a spectrally-matched pH-responsive fluorophore and a receptor-targeting group. By combining these elements, we observed switchable LRET, where the targeting group sensitises lanthanide emission, resulting in an energy transfer to the rhodamine dye with an efficiency of E = 0.53. This strategy can be used to increase lanthanide emission rates for brighter optical probes. A pH-sensitive luminescence resonance energy transfer (LRET) was explored as a method to increase photon flux in a terbium-rhodamine-receptor targeting group construct. At low pH, long-lived dye emission and shorter terbium lifetimes were observed.![]()
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Affiliation(s)
- Tamara Boltersdorf
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub London W12 0BZ UK
| | - Felicity N E Gavins
- Department of Life Sciences, Centre for Inflammation Research and Translational Medicine (CIRTM), Brunel University London Uxbridge Middlesex UB8 3PH UK
| | - Nicholas J Long
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub London W12 0BZ UK
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20
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Kovacs D, Kocsi D, Wells JAL, Kiraev SR, Borbas KE. Electron transfer pathways in photoexcited lanthanide(iii) complexes of picolinate ligands. Dalton Trans 2021; 50:4244-4254. [PMID: 33688904 DOI: 10.1039/d1dt00616a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A series of luminescent lanthanide(iii) complexes consisting of 1,4,7-triazacyclononane frameworks and three secondary amide-linked carbostyril antennae were synthesised. The metal binding sites were augmented with two pyridylcarboxylate donors yielding octadentate ligands. The antennae carried methyl, methoxymethyl or trifluoromethyl substituents in their 4-positions, allowing for a range of excited state energies and antenna electronic properties. The 1H NMR spectra of the Eu(iii) complexes were found to be analogous to each other. Similar results were obtained in the solid-state by single-crystal X-ray crystallography, which showed the structures to have nine-coordinate metal ions with heavily distorted tricapped trigonal prismatic geometries. Steady-state and time-resolved luminescence spectroscopy showed that the antennae could sensitize both Tb(iii) and Eu(iii), however, quantum yields were lower than in other octadentate complexes lacking pyridylcarboxylate. Complexes with more electron-poor pyridines were less emissive even when equipped with the same antenna. The oxidation and reduction potentials of the antennae and the pyridinecarboxylates, respectively, were determined by cyclic voltammetry. The obtained values were consistent with electron transfer from the excited antenna to the pyridine providing a previously unexplored quenching pathway that could efficiently compete with energy transfer to the lanthanide. These results show the crucial impact that photophysically innocent ligand binding sites can have on lanthanide luminescence.
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Affiliation(s)
- Daniel Kovacs
- Department of Chemistry, Ångström Laboratory, Box 523, Uppsala University, 75120, Uppsala, Sweden.
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21
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Pham H, Miller LW. Lanthanide-based resonance energy transfer biosensors for live-cell applications. Methods Enzymol 2021; 651:291-311. [PMID: 33888207 DOI: 10.1016/bs.mie.2021.01.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Lanthanide-based, Förster resonance energy transfer (LRET) biosensors enable sensitive, time-gated luminescence (TGL) imaging or multiwell plate analysis of protein-protein interactions (PPIs) in living mammalian cells. LRET biosensors are polypeptides that consist of an alpha-helical linker sequence sandwiched between a lanthanide complex-binding domain and a fluorescent protein (FP) with two interacting domains residing at each terminus. Interaction between the terminal affinity domains brings the lanthanide complex and FP in close proximity such that lanthanide-to-FP, LRET-sensitized emission is increased. A recent proof-of-concept study examined model biosensors that incorporated the affinity partners FKBP12 and the rapamycin-binding domain of m-Tor (FRB) as well as p53 (1-92) and HDM2 (1-128). The sensors contained an Escherichia coli dihydrofolate reductase (eDHFR) domain that binds with high selectivity and affinity to Tb(III) complexes coupled to the ligand trimethoprim (TMP). When cell lines that stably expressed the sensors were treated with TMP-Tb(III), TGL microscopy revealed dramatic differences (>500%) in donor- or acceptor-denominated, Tb(III)-to-GFP LRET ratios between open (unbound) and closed (bound) states of the biosensors. Much larger signal changes (>2500%) and Z'-factors of 0.5 or more were observed when cells were grown in 96-well or 384-well plates and analyzed using a TGL plate reader. In this chapter, we elaborate on the design and performance of LRET biosensors and provide detailed protocols to guide their use for live-cell microscopic imaging studies and high-throughput library screening.
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Affiliation(s)
- Ha Pham
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, United States
| | - Lawrence W Miller
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, United States.
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22
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New 1,3-Disubstituted Benzo[ h]Isoquinoline Cyclen-Based Ligand Platform: Synthesis, Eu 3+ Multiphoton Sensitization and Imaging Applications. Molecules 2020; 26:molecules26010058. [PMID: 33374449 PMCID: PMC7795479 DOI: 10.3390/molecules26010058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 12/15/2020] [Accepted: 12/17/2020] [Indexed: 11/17/2022] Open
Abstract
The development of lanthanide-based luminescent probes with a long emission lifetime has the potential to revolutionize imaging-based diagnostic techniques. By a rational design strategy taking advantage of computational predictions, a novel, water-soluble Eu3+ complex from a cyclen-based ligand bearing 1,3-disubstituted benzo[h]isoquinoline arms was realized. The ligand has been obtained overcoming the lack of reactivity of position 3 of the isoquinoline moiety. Notably, steric hindrance of the heteroaromatic chromophore allowed selective and stoichiometry-controlled insertion of two or three antennas on the cyclen platform without any protection strategy. The complex bears a fourth heptanoic arm for easy conjugation to biomolecules. This new chromophore allowed the sensitization of the metal center either with one or two photons excitation. The suitability as a luminescent bioprobe was validated by imaging BMI1 oncomarker in lung carcinoma cells following an established immunofluorescence approach. The use of a conventional epifluorescence microscope equipped with a linear structured illumination module disclosed a simple and inexpensive way to image confocally Ln-bioprobes by single photon excitation in the 350–400 nm window, where ordinary confocal systems have no excitation sources.
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23
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Smrčka F, Lubal P. Luminescent Sensor Based on Ln(III) Ternary Complexes for NAD(P)H Detection. Molecules 2020; 25:E4164. [PMID: 32932963 PMCID: PMC7571129 DOI: 10.3390/molecules25184164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/05/2020] [Accepted: 09/07/2020] [Indexed: 11/16/2022] Open
Abstract
Ln(III) complexes of macrocyclic ligands are used in medicinal chemistry, for example as contrast agents in MRI or radiopharmaceutical compounds, and in diagnostics using fluorescence imaging. This paper is devoted to a spectroscopic study of Ln(III) ternary complexes consisting of macrocyclic heptadentate DO3A and bidentate 3-isoquinolinate (IQCA) ligands. IQCA serves as an efficient antenna ligand, leading to a higher quantum yield and Stokes shift (250-350 nm for Eu, Tb, Sm, Dy in VIS region, 550-650 nm for Yb, Nd in NIR region). The shielding-quenching effect of NAD(P)H on the luminescence of the Ln(III) ternary complexes was investigated in detail and this phenomenon was utilized for the analytical determination of this compound. This general approach was verified through an enzymatic reaction during which the course of ethanol transformation catalyzed by alcohol-dehydrogenase (ADH) was followed by luminescence spectroscopy. This method can be utilized for selective and sensitive determination of ethanol concentration and/or ADH enzyme activity. This new analytical method can also be used for other enzyme systems coupled with NAD(P)H/NAD(P)+ redox pairs.
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Affiliation(s)
| | - Přemysl Lubal
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic;
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24
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Chen T, Pham H, Mohamadi A, Miller LW. Single-Chain Lanthanide Luminescence Biosensors for Cell-Based Imaging and Screening of Protein-Protein Interactions. iScience 2020; 23:101533. [PMID: 33083762 PMCID: PMC7509216 DOI: 10.1016/j.isci.2020.101533] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/23/2020] [Accepted: 09/02/2020] [Indexed: 11/27/2022] Open
Abstract
Lanthanide-based, Förster resonance energy transfer (LRET) biosensors enabled sensitive, time-gated luminescence (TGL) imaging or multiwell plate analysis of protein-protein interactions (PPIs) in living cells. We prepared stable cell lines that expressed polypeptides composed of an alpha helical linker flanked by a Tb(III) complex-binding domain, GFP, and two interacting domains at each terminus. The PPIs examined included those between FKBP12 and the rapamycin-binding domain of m-Tor (FRB) and between p53 (1–92) and HDM2 (1–128). TGL microscopy revealed dramatic differences (>500%) in donor- or acceptor-denominated, Tb(III)-to-GFP LRET ratios between open (unbound) and closed (bound) states of the biosensors. We observed much larger signal changes (>2,500%) and Z′-factors of 0.5 or more when we grew cells in 96- or 384-well plates and analyzed PPI changes using a TGL plate reader. The modular design and exceptional dynamic range of lanthanide-based LRET biosensors will facilitate versatile imaging and cell-based screening of PPIs. Non-invasive, microscopic imaging or screening of protein-protein interactions Intracellular assembly of sensor polypeptides with luminescent Tb(III) complexes High dynamic range with time-gated detection of Tb(III)-to-GFP sensitized emission
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Affiliation(s)
- Ting Chen
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, USA
| | - Ha Pham
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, USA
| | - Ali Mohamadi
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, USA
| | - Lawrence W. Miller
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL, USA
- Corresponding author
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25
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Bhuckory S, Wegner KD, Qiu X, Wu YT, Jennings TL, Incamps A, Hildebrandt N. Triplexed CEA-NSE-PSA Immunoassay Using Time-Gated Terbium-to-Quantum Dot FRET. Molecules 2020; 25:molecules25163679. [PMID: 32806745 PMCID: PMC7464126 DOI: 10.3390/molecules25163679] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/06/2020] [Accepted: 08/09/2020] [Indexed: 12/12/2022] Open
Abstract
Time-gated Förster resonance energy transfer (TG-FRET) between Tb complexes and luminescent semiconductor quantum dots (QDs) provides highly advantageous photophysical properties for multiplexed biosensing. Multiplexed Tb-to-QD FRET immunoassays possess a large potential for in vitro diagnostics, but their performance is often insufficient for their application under clinical conditions. Here, we developed a homogeneous TG-FRET immunoassay for the quantification of carcinoembryonic antigen (CEA), neuron-specific enolase (NSE), and prostate-specific antigen (PSA) from a single serum sample by multiplexed Tb-to-QD FRET. Tb–IgG antibody donor conjugates were combined with compact QD-F(ab’)2 antibody acceptor conjugates with three different QDs emitting at 605, 650, and 705 nm. Upon antibody–antigen–antibody sandwich complex formation, the QD acceptors were sensitized via FRET from Tb, and the FRET ratios of QD and Tb TG luminescence intensities increased specifically with increasing antigen concentrations. Although limits of detection (LoDs: 3.6 ng/mL CEA, 3.5 ng/mL NSE, and 0.3 ng/mL PSA) for the triplexed assay were slightly higher compared to the single-antigen assays, they were still in a clinically relevant concentration range and could be quantified in 50 µL serum samples on a B·R·A·H·M·S KRYPTOR Compact PLUS clinical immunoassay plate reader. The simultaneous quantification of CEA, NSE, and PSA at different concentrations from the same serum sample demonstrated actual multiplexing Tb-to-QD FRET immunoassays and the potential of this technology for translation into clinical diagnostics.
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Affiliation(s)
- Shashi Bhuckory
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, 91198 Gif-sur-Yvette, France; (S.B.); (X.Q.); (Y.-T.W.)
| | - K. David Wegner
- Federal Institute for Materials Research and Testing (BAM), Division Biophotonics, Richard-Willstaetter-Strasse 11, 12489 Berlin, Germany;
| | - Xue Qiu
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, 91198 Gif-sur-Yvette, France; (S.B.); (X.Q.); (Y.-T.W.)
- School of Medicine and Pharmacy, Ocean University of China. 5, Yushan Road, Qingdao 266003, Shandong, China
| | - Yu-Tang Wu
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, 91198 Gif-sur-Yvette, France; (S.B.); (X.Q.); (Y.-T.W.)
| | | | - Anne Incamps
- Thermo Fisher Scientific Cezanne SAS, Clinical Diagnostic Division, 30000 Nimes, France;
| | - Niko Hildebrandt
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, 91198 Gif-sur-Yvette, France; (S.B.); (X.Q.); (Y.-T.W.)
- Laboratoire COBRA (Chimie Organique, Bioorganique, Réactivité et Analyse), Université de Rouen Normandie, CNRS, INSA, 76821 Mont-Saint-Aignan, France
- Correspondence:
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26
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Hummel T, Leis W, Eckhardt A, Ströbele M, Enseling D, Jüstel T, Meyer HJ. Energy transfer in supramolecular [Crypt-RE]-[W 6I 14] solids. Dalton Trans 2020; 49:9795-9803. [PMID: 32627778 DOI: 10.1039/d0dt01705a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Photophysical properties of tungsten iodides with the [W6I14]2- cluster core have been described with respect to phosphorescence and phosphorescence quenching by molecular oxygen. This process involves energy transfer from excited triplet states of the cluster onto molecular oxygen. In the present study we investigate deactivation channels of exited triplet states of the [W6I14]2- cluster towards rare earth ions. For this purpose, we synthesized several supramolecular assemblies made of [W6I14]2- clusters and metal cryptates and investigated their crystal structures and photophysical properties. UV/Vis photoexcitation of solid [Crypt-A]-[W6I14] (A = alkaline metal) and [Crypt-RE]-[W6I14] revealed phosphorescence of the cluster, respectively of the photophysically active rare earth metal (RE) center. A cluster to cryptate energy transfer is proven with a photophysically active rare earth ion by the emission of Yb3+ at 977 nm (2F5/2-2F7/2) and Nd3+ 1072 nm (4F3/2-4I11/2). These results show that an effective excitation of near-infrared-emitting rare earth ions is possible under excitation up to 550 nm with [Crypt-RE]-[W6I14] assemblies.
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Affiliation(s)
- Thorsten Hummel
- Section for Solid State and Theoretical Inorganic Chemistry, Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany.
| | - Wolfgang Leis
- Section for Translational Chemistry, Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Aaron Eckhardt
- Section for Solid State and Theoretical Inorganic Chemistry, Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany.
| | - Markus Ströbele
- Section for Solid State and Theoretical Inorganic Chemistry, Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany.
| | - David Enseling
- Department of Chemical Engineering, Münster University of Applied Sciences, Stegerwaldstraße 39, 48565 Steinfurt, Germany
| | - Thomas Jüstel
- Department of Chemical Engineering, Münster University of Applied Sciences, Stegerwaldstraße 39, 48565 Steinfurt, Germany
| | - Hans-Jürgen Meyer
- Section for Solid State and Theoretical Inorganic Chemistry, Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany.
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Del Giorgio E, Sørensen TJ. HOCl Responsive Lanthanide Complexes Using Hydroquinone Caging Units. Molecules 2020; 25:E1959. [PMID: 32340115 PMCID: PMC7221670 DOI: 10.3390/molecules25081959] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 04/16/2020] [Accepted: 04/18/2020] [Indexed: 01/14/2023] Open
Abstract
Redox biology is still looking for tools to monitor redox potential in cellular biology and, despite a large and sustained effort, reliable molecular probes have yet to emerge. In contrast, molecular probes for reactive oxygen and nitrogen have been widely explored. In this manuscript, three kinetically inert lanthanide complexes that selectively react with hypochlorous acid are prepared and characterized. The design is based on 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A) and 1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (DO2A) ligands appended with one or two redox active hydroquinone derived arms, thereby forming octadentate ligands ideally suited to complex trivalent lanthanide ions. The three complexes are found to react selectively with hypochlorous acid to form highly symmetric lanthanide(III) 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacedic acid (DOTA) complexes. The conversion of the probe to [Ln.DOTA]- is followed by luminescence, absorption, and NMR spectroscopy in a model system comprised of a Triton-X modified HEPES buffer. It was concluded that the design principle works, and that simple caging units like hydroquinones can work well in conjugation with lanthanide(III) complexes.
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Affiliation(s)
| | - Thomas Just Sørensen
- Nano-Science Center & Department of Chemistry, University of Copenhagen, Universitetsparken5, 2100 København Ø, Denmark;
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Kreidt E, Leis W, Seitz M. Direct solid-phase synthesis of molecular heterooligonuclear lanthanoid-complexes. Nat Commun 2020; 11:1346. [PMID: 32165625 PMCID: PMC7067767 DOI: 10.1038/s41467-020-15199-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 02/24/2020] [Indexed: 01/10/2023] Open
Abstract
Molecular lanthanoid complexes are highly valuable building blocks for a number of important technological applications, e.g. as contrast agents in magnetic resonance imaging (MRI) or as luminescent probes for bioassays. For the next generation of advanced applications based on molecular species, heterooligonuclear lanthanoid complexes with well-defined chemical and structural compositions are required. The great kinetic lability of trivalent lanthanoids so far prevents the realization of such molecular architectures with a universally applicable methodology. Here, we have developed functionalized molecular lanthanoid cryptates as monomeric building blocks which can be directly linked by standard solid-phase peptide synthesis to yield sequence-specific heterooligonuclear lanthanoid complexes. These molecular materials enable unique applications such as the generation of molecular codes with very convenient luminescence read-out.
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Affiliation(s)
- Elisabeth Kreidt
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Wolfgang Leis
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Michael Seitz
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany.
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29
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30
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Leygue N, Galaup C, Lopera A, Delgado-Pinar E, Williams RM, Gornitzka H, Zwier JM, García-España E, Lamarque L, Picard C. Tripyridinophane Platform Containing Three Acetate Pendant Arms: An Attractive Structural Entry for the Development of Neutral Eu(III) and Tb(III) Complexes in Aqueous Solution. Inorg Chem 2020; 59:1496-1512. [PMID: 31913029 DOI: 10.1021/acs.inorgchem.9b03345] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We report a detailed characterization of Eu3+ and Tb3+ complexes derived from a tripyridinophane macrocycle bearing three acetate side arms (H3tpptac). Tpptac3- displays an overall basicity (∑ log KiH) of 24.5, provides the formation of mononuclear ML species, and shows a good binding affinity for Ln3+ (log KLnL = 17.5-18.7). These complexes are also thermodynamically stable at physiological pH (pEu = 18.6, pTb = 18.0). It should be noted that the pGd value of Gd-tpptac (18.4) is only slightly lower than that of commercially available MRI contrast agents such as Gd-dota (pGd = 19.2). Moreover, a very good selectivity for these ions over the endogenous cations (log KCuL = 14.4, log KZnL = 12.9, and log KCaL = 9.3) is observed. The X-ray structure of the terbium complex shows the metal coordinated by the nine N6O3 donor set of the ligand and one inner-sphere water molecule. DFT calculations result in two Eu-tpptac structures with similar bond energies (ΔE = 0.145 eV): one structure in which the water is coordinated to the metal ion and one structure in which the water molecule is farther away from the ion, bound to the ligand with an OH-π bond. By detailed luminescence experiments, we demonstrate that the europium complex in aqueous solution presents a hydration equilibrium between nine-coordinate, dehydrated [Eu-tpptac]0 and ten-coordinate, monohydrated [Eu-tpptac(H2O)]0 species. A similar trend is observed for the terbium complex. Despite the presence of this hydration equilibrium, the H3tpptac ligand sensitizes Eu3+ and Tb3+ luminescence efficiently in buffered water at physiological pH. Particularly, the terbium complex displays a long excited-state lifetime of 2.24 ms and an overall quantum yield of 33% with a brightness of 3600 M-1 cm-1. Such features of Ln3+ complexes of H3tpptac indicate that this platform appears to be particularly appealing for the further development of luminescent lanthanide labels.
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Affiliation(s)
- Nadine Leygue
- Laboratoire de Synthèse et Physico-Chimie de Molécules d'Intérêt Biologique (SPCMIB) , Université Paul Sabatier-Toulouse III/CNRS (UMR5068) , 118 route de Narbonne , F-31062 Toulouse , France
| | - Chantal Galaup
- Laboratoire de Synthèse et Physico-Chimie de Molécules d'Intérêt Biologique (SPCMIB) , Université Paul Sabatier-Toulouse III/CNRS (UMR5068) , 118 route de Narbonne , F-31062 Toulouse , France
| | - Alberto Lopera
- Instituto de Ciencia Molecular (ICMOL) , Universitat de València , C/Catedrático José Beltrán 2 , 46980 Paterna , Spain
| | - Estefanía Delgado-Pinar
- Instituto de Ciencia Molecular (ICMOL) , Universitat de València , C/Catedrático José Beltrán 2 , 46980 Paterna , Spain
| | - René M Williams
- Molecular Photonics Group, Van 't Hoff Institute for Molecular Sciences , University of Amsterdam , P.O. Box 94157, 1090 GD Amsterdam , The Netherlands
| | - Heinz Gornitzka
- CNRS, LCC , Université de Toulouse, UPS, INPT , 205 Route de Narbonne , F-31077 Toulouse Cedex 4 , France
| | - Jurriaan M Zwier
- Cisbio bioassays , Parc Marcel Boiteux, BP 84175, 30200 Codolet , France
| | - Enrique García-España
- Instituto de Ciencia Molecular (ICMOL) , Universitat de València , C/Catedrático José Beltrán 2 , 46980 Paterna , Spain
| | - Laurent Lamarque
- Cisbio bioassays , Parc Marcel Boiteux, BP 84175, 30200 Codolet , France
| | - Claude Picard
- Laboratoire de Synthèse et Physico-Chimie de Molécules d'Intérêt Biologique (SPCMIB) , Université Paul Sabatier-Toulouse III/CNRS (UMR5068) , 118 route de Narbonne , F-31062 Toulouse , France
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31
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pH dependence of water anomaly temperature investigated by Eu(III) cryptate luminescence. Anal Bioanal Chem 2019; 412:73-80. [PMID: 31776644 DOI: 10.1007/s00216-019-02215-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 09/23/2019] [Accepted: 10/15/2019] [Indexed: 12/20/2022]
Abstract
Although water has been extensively studied, not all of its unique properties have been fully understood. There is still controversy about the temperature at which hydrogen bonds are broken or weakened, producing the anomalous temperature dependence of many water properties. Different temperatures between 23 and 48 °C have been reported, but no study has scrutinized the reasons for this discrepancy. We suggest the determining role of pH in the alteration of the water anomaly temperature. We employed a luminescent europium trisbipyridine cryptate, which is highly sensitive to changes in the arrangement of water molecules and whose luminescence intensity and lifetime are not significantly influenced by variations over a broad pH range. Our results revealed an increase of the crossover temperature from circa 35 °C at pH 3.5 to circa 45 °C at pH 7 to 9, which explains the discrepancies of previous studies. The pH dependence of water anomaly temperature is an important property for a better understanding of water and water-based systems and applications.
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Trautnitz MFK, Doffek C, Seitz M. Radiative Lifetime, Non-Radiative Relaxation, and Sensitization Efficiency in Luminescent Europium and Neodymium Cryptates - The Roles of 2,2'-Bipyridine-N,N'-dioxide and Deuteration. Chemphyschem 2019; 20:2179-2186. [PMID: 31304640 DOI: 10.1002/cphc.201900673] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 07/09/2019] [Indexed: 02/01/2023]
Abstract
Five luminescent tris(bipyridine)-based cryptates with the lanthanoids Eu and Nd have been prepared with a systematic increase in the number of 2,2'-bipyridine-N,N'-dioxide units and with different deuteration levels in the complexing cryptands for the europium species. Careful analysis of the radiative lifetime τrad in these systems reveals that an increase in N-oxide units around the metal centers uniformly lowers τrad by about 30-40 %. The potential involvement of nephelauxetic effects is discussed. Exchange of 30 C-D for C-H oscillators around the europium centers does not affect the radiative lifetimes but decreases non-radiative deactivation and increases the overall luminescence quantum yield in D2 O by 45 %.
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Affiliation(s)
- Markus F K Trautnitz
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
| | - Christine Doffek
- Inorganic Chemistry I, Ruhr-University Bochum, 44780, Bochum, Germany
| | - Michael Seitz
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076, Tübingen, Germany
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33
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Kofod N, Arppe-Tabbara R, Sørensen TJ. Electronic Energy Levels of Dysprosium(III) ions in Solution. Assigning the Emitting State and the Intraconfigurational 4f–4f Transitions in the Vis–NIR Region and Photophysical Characterization of Dy(III) in Water, Methanol, and Dimethyl Sulfoxide. J Phys Chem A 2019; 123:2734-2744. [DOI: 10.1021/acs.jpca.8b12034] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Nicolaj Kofod
- Department of Chemistry & Nano-Science Center, University of Copenhagen, Universitetsparken 5, 2100 København Ø, Denmark
| | - Riikka Arppe-Tabbara
- Department of Chemistry & Nano-Science Center, University of Copenhagen, Universitetsparken 5, 2100 København Ø, Denmark
| | - Thomas Just Sørensen
- Department of Chemistry & Nano-Science Center, University of Copenhagen, Universitetsparken 5, 2100 København Ø, Denmark
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34
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Microplate-based surface area assay for rapid phenotypic antibiotic susceptibility testing. Sci Rep 2019; 9:237. [PMID: 30659207 PMCID: PMC6338723 DOI: 10.1038/s41598-018-35916-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 11/08/2018] [Indexed: 11/08/2022] Open
Abstract
Rapid delivery of proper antibiotic therapies to infectious disease patients is essential for improving patient outcomes, decreasing hospital lengths-of-stay, and combating the antibiotic resistance epidemic. Antibiotic stewardship programs are designed to address these issues by coordinating hospital efforts to rapidly deliver the most effective antibiotics for each patient, which requires bacterial identification and antimicrobial susceptibility testing (AST). Despite the clinical need for fast susceptibility testing over a wide range of antibiotics, conventional phenotypic AST requires overnight incubations, and new rapid phenotypic AST platforms restrict the number of antibiotics tested for each patient. Here, we introduce a novel approach to AST based on signal amplification of bacterial surfaces that enables phenotypic AST within 5 hours for non-fastidious bacteria. By binding bacterial surfaces, this novel method allows more accurate measurements of bacterial replication in instances where organisms filament or swell in response to antibiotic exposure. Further, as an endpoint assay performed on standard microplates, this method should enable parallel testing of more antibiotics than is currently possible with available automated systems. This technology has the potential to revolutionize clinical practice by providing rapid and accurate phenotypic AST data for virtually all available antibiotics in a single test.
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35
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Nonat A, Esteban-Gómez D, Valencia L, Pérez-Lourido P, Barriada JL, Charbonnière LJ, Platas-Iglesias C. The role of ligand to metal charge-transfer states on the luminescence of Europium complexes with 18-membered macrocyclic ligands. Dalton Trans 2019; 48:4035-4045. [DOI: 10.1039/c8dt05005h] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The stabilization of a divalent Europium provides an efficient pathway for the quenching of the luminescence in ten-coordinate macrocyclic complexes.
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Affiliation(s)
- Aline Nonat
- Synthèse pour l'Analyse (SynPA)
- Institut Pluridisciplinaire Hubert Curien (IPHC
- UMR 7178
- CNRS/Université de Strasbourg)
- ECPM
| | - David Esteban-Gómez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química
- Universidade da Coruña
- Campus da Zapateira-Rúa da Fraga 10
- 15008 A Coruña
- Spain
| | - Laura Valencia
- Departamento de Química Inorgánica
- Facultad de Ciencias
- Universidade de Vigo
- 36310 Pontevedra
- Spain
| | - Paulo Pérez-Lourido
- Departamento de Química Inorgánica
- Facultad de Ciencias
- Universidade de Vigo
- 36310 Pontevedra
- Spain
| | - José Luis Barriada
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química
- Universidade da Coruña
- Campus da Zapateira-Rúa da Fraga 10
- 15008 A Coruña
- Spain
| | - Loïc J. Charbonnière
- Synthèse pour l'Analyse (SynPA)
- Institut Pluridisciplinaire Hubert Curien (IPHC
- UMR 7178
- CNRS/Université de Strasbourg)
- ECPM
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química
- Universidade da Coruña
- Campus da Zapateira-Rúa da Fraga 10
- 15008 A Coruña
- Spain
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36
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Junker AKR, Sørensen TJ. Shining light on the excited state energy cascade in kinetically inert Ln(iii) complexes of a coumarin-appended DO3A ligand. Dalton Trans 2019; 48:964-970. [DOI: 10.1039/c8dt04464c] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Lanthanide based molecular probes for bioimaging relies on the antenna effect, here we are unravelling the excited state energy cascade that results in sensitized lanthanide luminescence.
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Affiliation(s)
- Anne Kathrine R. Junker
- Nano-Science Center & Department of Chemistry
- University of Copenhagen
- 2100 København Ø
- Denmark
| | - Thomas Just Sørensen
- Nano-Science Center & Department of Chemistry
- University of Copenhagen
- 2100 København Ø
- Denmark
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37
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Belhocine A, Veglianese P, Hounsou C, Dupuis E, Acher F, Durroux T, Goudet C, Pin JP. Profiling of orthosteric and allosteric group-III metabotropic glutamate receptor ligands on various G protein-coupled receptors with Tag-lite ® assays. Neuropharmacology 2018; 140:233-245. [PMID: 30099051 DOI: 10.1016/j.neuropharm.2018.07.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 07/25/2018] [Accepted: 07/26/2018] [Indexed: 12/21/2022]
Abstract
Group-III metabotropic glutamate (mGlu) receptors are important synaptic regulators and are potential druggable targets for Parkinson disease, autism and pain. Potential drugs include orthosteric agonists in the glutamate binding extracellular domain and positive allosteric modulators interacting with seven-pass transmembrane domains. Orthosteric agonists are rarely completely specific for an individual group-III mGlu subtype. Furthermore they often fail to pass the blood-brain barrier and they constitutively activate their target receptor. These properties limit the potential therapeutic use of orthosteric agonists. Allosteric modulators are more specific and maintain the biological activity of the targeted receptor. However, they bind in a hydrophobic pocket and this limits their bio-availability and increases possible off-target action. It is therefore important to characterize the action of potential drug targets with a multifaceted and deeply informative assay. Here we aimed at multifaceted deep profiling of the effect of seven different agonists, and seven positive allosteric modulators on 34 different G protein-coupled receptors by a Tag-lite® assay. Our results did not reveal off-target activity of mGlu orthosteric agonists. However, five allosteric modulators had either positive or negative effects on non-cognate G protein-coupled receptors. In conclusion, we demonstrate the power of the Tag-lite® assay for potential drug ligand profiling on G protein-coupled receptors and its potential to identify positive allosteric compounds.
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Affiliation(s)
| | | | | | | | - Francine Acher
- Laboratoire de Chimie et de Biochimie Pharmacologiques et Toxicologiques, CNRS UMR8601, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | | | - Cyril Goudet
- IGF, Univ. Montpellier, CNRS, INSERM, Montpellier, France
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38
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New advances in the synthesis of tripyridinophane macrocycles suitable to enhance the luminescence of Ln(III) ions in aqueous solution. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.06.056] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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39
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Arppe‐Tabbara R, Carro‐Temboury MR, Hempel C, Vosch T, Sørensen TJ. Luminescence from Lanthanide(III) Ions Bound to the Glycocalyx of Chinese Hamster Ovary Cells. Chemistry 2018; 24:11885-11889. [DOI: 10.1002/chem.201802799] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 06/25/2018] [Indexed: 12/26/2022]
Affiliation(s)
- Riikka Arppe‐Tabbara
- Nano-Science Center & Department of ChemistryUniversity of Copenhagen Universitetsparken 5 2100 København Ø Denmark
| | - Miguel R. Carro‐Temboury
- Nano-Science Center & Department of ChemistryUniversity of Copenhagen Universitetsparken 5 2100 København Ø Denmark
| | - Casper Hempel
- Department of Micro- and NanotechnologyTechnical University of Denmark Kgs Lyngby Denmark
| | - Tom Vosch
- Nano-Science Center & Department of ChemistryUniversity of Copenhagen Universitetsparken 5 2100 København Ø Denmark
| | - Thomas Just Sørensen
- Nano-Science Center & Department of ChemistryUniversity of Copenhagen Universitetsparken 5 2100 København Ø Denmark
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40
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Hewitt SH, Butler SJ. Application of lanthanide luminescence in probing enzyme activity. Chem Commun (Camb) 2018; 54:6635-6647. [PMID: 29790500 DOI: 10.1039/c8cc02824a] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Enzymes play critical roles in the regulation of cellular function and are implicated in numerous disease conditions. Reliable and practicable assays are required to study enzyme activity, to facilitate the discovery of inhibitors and activators of enzymes related to disease. In recent years, a variety of enzyme assays have been devised that utilise luminescent lanthanide(iii) complexes, taking advantage of their high detection sensitivities, long luminescence lifetimes, and line-like emission spectra that permit ratiometric and time-resolved analyses. In this Feature article, we focus on recent progress in the development of enzyme activity assays based on lanthanide(iii) luminescence, covering a variety of strategies including Ln(iii)-labelled antibodies and proteins, Ln(iii) ion encapsulation within defined peptide sequences, reactivity-based Ln(iii) probes, and discrete Ln(iii) complexes. Emerging approaches for monitoring enzyme activity are discussed, including the use of anion responsive lanthanide(iii) complexes, capable of molecular recognition and luminescence signalling of polyphosphate anions.
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Affiliation(s)
- Sarah H Hewitt
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
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41
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Dee C, Esteban-Gómez D, Platas-Iglesias C, Seitz M. Long Wavelength Excitation of Europium Luminescence in Extended, Carboline-Based Cryptates. Inorg Chem 2018; 57:7390-7401. [DOI: 10.1021/acs.inorgchem.8b01031] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Carolin Dee
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - David Esteban-Gómez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Universidade da Coruña, Campus da Zapateira-Rúa da Fraga 10, 15008 A Coruña, Spain
| | - Michael Seitz
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
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42
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Le Fur M, Molnár E, Beyler M, Fougère O, Esteban-Gómez D, Rousseaux O, Tripier R, Tircsó G, Platas-Iglesias C. Expanding the Family of Pyclen-Based Ligands Bearing Pendant Picolinate Arms for Lanthanide Complexation. Inorg Chem 2018; 57:6932-6945. [DOI: 10.1021/acs.inorgchem.8b00598] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Mariane Le Fur
- Université de Bretagne Occidentale, UMR-CNRS 6521, IBSAM, UFR des Sciences et Techniques, 6 avenue Victor le Gorgeu, C.S. 93837, 29238 Brest Cedex 3, France
| | - Enikő Molnár
- Department of Inorganic and Analytical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary
| | - Maryline Beyler
- Université de Bretagne Occidentale, UMR-CNRS 6521, IBSAM, UFR des Sciences et Techniques, 6 avenue Victor le Gorgeu, C.S. 93837, 29238 Brest Cedex 3, France
| | - Olivier Fougère
- Groupe Guerbet,
Centre de Recherche d’Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG Cedex, France
| | - David Esteban-Gómez
- Departamento de Química, Facultade de Ciencias & Centro de Investigaciones Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain
| | - Olivier Rousseaux
- Groupe Guerbet,
Centre de Recherche d’Aulnay-sous-Bois, BP 57400, 95943 Roissy CdG Cedex, France
| | - Raphaël Tripier
- Université de Bretagne Occidentale, UMR-CNRS 6521, IBSAM, UFR des Sciences et Techniques, 6 avenue Victor le Gorgeu, C.S. 93837, 29238 Brest Cedex 3, France
| | - Gyula Tircsó
- Department of Inorganic and Analytical Chemistry, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1, H-4032 Debrecen, Hungary
| | - Carlos Platas-Iglesias
- Departamento de Química, Facultade de Ciencias & Centro de Investigaciones Científicas Avanzadas (CICA), Universidade da Coruña, 15071 A Coruña, Spain
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43
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Kelley MP, Deblonde GJP, Su J, Booth CH, Abergel RJ, Batista ER, Yang P. Bond Covalency and Oxidation State of Actinide Ions Complexed with Therapeutic Chelating Agent 3,4,3-LI(1,2-HOPO). Inorg Chem 2018; 57:5352-5363. [DOI: 10.1021/acs.inorgchem.8b00345] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Morgan P. Kelley
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544, United States
| | - Gauthier J.-P. Deblonde
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Jing Su
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544, United States
| | - Corwin H. Booth
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Rebecca J. Abergel
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Enrique R. Batista
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544, United States
| | - Ping Yang
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544, United States
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44
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Ge M, Bai P, Chen M, Tian J, Hu J, Zhi X, Yin H, Yin J. Utilizing hyaluronic acid as a versatile platform for fluorescence resonance energy transfer-based glucose sensing. Anal Bioanal Chem 2018; 410:2413-2421. [DOI: 10.1007/s00216-018-0928-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/28/2017] [Accepted: 01/29/2018] [Indexed: 01/06/2023]
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45
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Kovacs D, Phipps D, Orthaber A, Borbas KE. Highly luminescent lanthanide complexes sensitised by tertiary amide-linked carbostyril antennae. Dalton Trans 2018; 47:10702-10714. [DOI: 10.1039/c8dt01270a] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The replacement of the secondary amide linker that carries the sensitizing carbostyril antenna with a tertiary amide in luminescent Eu and Tb complexes dramatically increases the lanthanide emission quantum yields.
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Affiliation(s)
- Daniel Kovacs
- Department of Chemistry
- Ångström Laboratory
- Uppsala University
- Uppsala
- Sweden
| | - Dulcie Phipps
- Department of Chemistry
- Ångström Laboratory
- Uppsala University
- Uppsala
- Sweden
| | - Andreas Orthaber
- Department of Chemistry
- Ångström Laboratory
- Uppsala University
- Uppsala
- Sweden
| | - K. Eszter Borbas
- Department of Chemistry
- Ångström Laboratory
- Uppsala University
- Uppsala
- Sweden
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46
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Lecat-Guillet N, Monnier C, Rovira X, Kniazeff J, Lamarque L, Zwier JM, Trinquet E, Pin JP, Rondard P. FRET-Based Sensors Unravel Activation and Allosteric Modulation of the GABA B Receptor. Cell Chem Biol 2017; 24:360-370. [PMID: 28286129 DOI: 10.1016/j.chembiol.2017.02.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 11/21/2016] [Accepted: 02/10/2017] [Indexed: 01/11/2023]
Abstract
The main inhibitory neurotransmitter, γ-aminobutyric acid (GABA), modulates many synapses by activating the G protein-coupled receptor GABAB, which is a target for various therapeutic applications. It is an obligatory heterodimer made of GB1 and GB2 that can be regulated by positive allosteric modulators (PAMs). The molecular mechanism of activation of the GABAB receptor remains poorly understood. Here, we have developed FRET-based conformational GABAB sensors compatible with high-throughput screening. We identified conformational changes occurring within the extracellular and transmembrane domains upon receptor activation, which are smaller than those observed in the related metabotropic glutamate receptors. These sensors also allow discrimination between agonists of different efficacies and between PAMs that have different modes of action, which has not always been possible using conventional functional assays. Our study brings important new information on the activation mechanism of the GABAB receptor and should facilitate the screening and identification of new chemicals targeting this receptor.
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Affiliation(s)
- Nathalie Lecat-Guillet
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France
| | - Carine Monnier
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France
| | - Xavier Rovira
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France
| | - Julie Kniazeff
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France
| | | | | | | | - Jean-Philippe Pin
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France
| | - Philippe Rondard
- Institut de Génomique Fonctionnelle (IGF), CNRS, INSERM, University of Montpellier, 141 rue de la Cardonille, 34094 Montpellier, France.
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47
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48
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Scholler P, Moreno-Delgado D, Lecat-Guillet N, Doumazane E, Monnier C, Charrier-Savournin F, Fabre L, Chouvet C, Soldevila S, Lamarque L, Donsimoni G, Roux T, Zwier JM, Trinquet E, Rondard P, Pin JP. HTS-compatible FRET-based conformational sensors clarify membrane receptor activation. Nat Chem Biol 2017; 13:372-380. [DOI: 10.1038/nchembio.2286] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 11/18/2016] [Indexed: 12/26/2022]
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49
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Martinez-Gomez NC, Vu HN, Skovran E. Lanthanide Chemistry: From Coordination in Chemical Complexes Shaping Our Technology to Coordination in Enzymes Shaping Bacterial Metabolism. Inorg Chem 2016; 55:10083-10089. [DOI: 10.1021/acs.inorgchem.6b00919] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Norma Cecilia Martinez-Gomez
- Department
of Microbiology and Molecular Genetics, Michigan State University, 567 Wilson Road, East Lansing, Michigan 48824, United States
| | - Huong N. Vu
- Department of Biological Sciences, San José State University, 1 Washington Square, San José, California 95192, United States
| | - Elizabeth Skovran
- Department of Biological Sciences, San José State University, 1 Washington Square, San José, California 95192, United States
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50
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Daumann LJ, Werther P, Ziegler MJ, Raymond KN. Siderophore inspired tetra- and octadentate antenna ligands for luminescent Eu(III) and Tb(III) complexes. J Inorg Biochem 2016; 162:263-273. [DOI: 10.1016/j.jinorgbio.2016.01.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 01/05/2016] [Accepted: 01/07/2016] [Indexed: 01/09/2023]
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