I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[40576]
Open Access
Abstract: Photocatalysis offers a promising approach for renewable energy conversion and storage, but short lifetimes of charge-separated states in photocatalysts due to charge recombination limit its utility. Here we report an organic molecule with an acceptor–donor–acceptor configuration that can self assemble into highly crystalline nanoparticles. Transient absorption spectroscopy reveals that these crystalline assemblies can induce an ultra-long-lived charge-separated state of up to 1.2 s, attributed to initial symmetry-breaking charge separation, followed by charge hopping across closely packed molecules. These self-assembled nanoparticles have an impressive photocatalytic H2 evolution rate of 126 mmol g−1 h−1 with an external quantum efficiency of 12% at 550 nm under optimized conditions. This system shows a remarkable stability with 220 million turnover numbers (per particle) over the 77 h of operation. These findings suggest that rational design of organic molecules and their aggregates is vital for improving light-induced charge separation and for developing highly efficient, stable and scalable organic photocatalysts.
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Jan 2026
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I09-Surface and Interface Structural Analysis
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Sarah May
Sibug-Torres
,
Marika
Niihori
,
Elle
Wyatt
,
Rakesh
Arul
,
Nicolas
Spiesshofer
,
Tabitha
Jones
,
Duncan
Graham
,
Bart
De Nijs
,
Oren A.
Scherman
,
Reshma R.
Rao
,
Mary P.
Ryan
,
Alexander
Squires
,
Christopher N.
Savory
,
David O.
Scanlon
,
Abdalghani
Daaoub
,
Sara
Sangtarash
,
Hatef
Sadeghi
,
Jeremy J.
Baumberg
Diamond Proposal Number(s):
[34784]
Open Access
Abstract: Controlling surface chemistry at the nanoscale is essential for stabilizing structure and tuning function in plasmonic, catalytic and sensing systems, where even trace ligands or ions can reshape surface charge and reactivity. However, probing such dynamic interfaces under operando conditions remains challenging, limiting efforts to engineer nanomaterials with precision. Here, using in situ surface-enhanced Raman spectroscopy, we identify a transient Au–Cl adlayer that forms during electrochemical cycling at gold interfaces. The adlayer exhibits significant charge transfer between gold and chlorine, generating an outward-facing dipole that polarizes neighbouring atoms and modulates the local potential. This dipole stabilizes nanogap interfaces and directs oriented ligand rebinding, enabling reversible reconstruction of subnanometre architectures. It also alters interfacial charge distributions and mediates electron transfer between gold oxidation states, acting as a redox-active intermediate. These findings show how transient surface species shape nanoscale reactivity and stability, offering strategies for designing catalysts, sensors and nanomaterials.
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Nov 2025
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I11-High Resolution Powder Diffraction
I19-Small Molecule Single Crystal Diffraction
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Inigo J.
Vitórica-Yrezábal
,
Craig A.
Mcanally
,
Matthew P.
Snelgrove
,
Mark R.
Warren
,
Adrian H.
Hill
,
Stephen P.
Thompson
,
Martin
Quinn
,
Sam
Mottley
,
Stephen
Mottley
,
Ashleigh J.
Fletcher
,
Lee
Brammer
Open Access
Abstract: Separation of CO2 from gas mixtures is important in applications such as CH4 gas purification and blue hydrogen production. Here we report selective CO2 uptake by a family of flexible silver coordination polymers (AgCPs) that are ostensibly non-porous but exhibit latent porosity to CO2 above a gate pressure, through a mechanism akin to dissolution in fluoroalkanes. The CO2 sorption properties are rationally modified by changing the perfluoroalkyl chain length of the constituent perfluorocarboxylate ligands. The AgCPs do not take up CH4 owing to failure of the dissolution mechanism, consistent with alkane–perfluoroalkane immiscibility. In situ single-crystal and powder X-ray diffraction enable direct visualization of the CO2 molecule binding domains. These techniques also reveal associated structural changes in the AgCPs and confirm the gating mechanism of CO2 uptake. The combination of perfluoroalkylcarboxylate ligands with the flexible silver(I) coordination sphere generates highly fluorinated but mobile regions of the crystals that play an integral role in the selective uptake of CO2 over CH4.
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Oct 2025
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I04-Macromolecular Crystallography
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Nai-Shu
Hsu
,
Cong
Tang
,
Raquel V.
Mendes
,
Carlos
Labão-Almeida
,
Caio V.
Dos Reis
,
Ana R.
Coelho
,
Marta C.
Marques
,
Mar
Cabeza Cabrerizo
,
Roman
Misteli
,
Timothy P. C.
Rooney
,
Marko
Hyvonen
,
Francisco
Corzana
,
Rita
Fior
,
Gonçalo J. L.
Bernardes
Diamond Proposal Number(s):
[35365]
Open Access
Abstract: Pharmacological activation of STING holds promise in cancer treatment. A recent trend is the development of tumour-specific or conditionally activated STING agonists for enhanced safety and efficacy. Here we explore an unconventional prodrug activation strategy for on-tumour synthesis of a potent agonist. Leveraging the unique mechanism of MSA2, a small-molecule agonist that dimerizes non-covalently before binding to STING, we showed that its analogues bearing reactive functional groups readily and selectively form covalent dimers under mild conditions and in complex environments. We identified a reacting pair that led to a thioether-linked dimer with submicromolar potency in cell-based assays. Caging one of the reactants with a self-immolative β-glucuronide moiety resulted in a two-component prodrug system that near-exclusively formed the active compounds in tumours overexpressing β-glucuronidase. These results exemplify the use of small-molecule recognition for on-site generation of active compounds from benign precursors.
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Sep 2025
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I03-Macromolecular Crystallography
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Rebecca
Crawshaw
,
Ross
Smithson
,
Johannes
Hofer
,
Florence J.
Hardy
,
George W.
Roberts
,
Jonathan S.
Trimble
,
Anna R.
Kohn
,
Colin W.
Levy
,
Deborah A.
Drost
,
Christian
Merten
,
Derren J.
Heyes
,
Richard
Obexer
,
Thorsten
Bach
,
Anthony P.
Green
Diamond Proposal Number(s):
[31850]
Open Access
Abstract: The development of [2 + 2] cyclases containing benzophenone triplet sensitizers highlights the potential of engineered enzymes as a platform for stereocontrolled energy transfer photocatalysis. However, the suboptimal photophysical features of benzophenone necessitates the use of ultraviolet light, limits photochemical efficiency and restricts the range of chemistries accessible. Here we engineer an orthogonal Methanococcus jannaschii tyrosyl-tRNA synthetase/tRNA pair for encoding thioxanthone triplet sensitizers into proteins, which can efficiently harness visible light to drive photochemical conversions. Initially, we developed an enantioselective [2 + 2] cyclase that is orders of magnitude more efficient than our previously developed photoenzymes (kcat = 13 s−1, >1,300 turnovers). To demonstrate that thioxanthone-containing enzymes can enable more challenging photochemical conversions, we developed a second oxygen-tolerant enzyme that can steer selective C–H insertions of excited quinolone substrates to afford spirocyclic β-lactams with high selectivity (99% e.e., 22:1 d.r.). This photoenzyme also suppresses a competing substrate decomposition pathway observed with small-molecule sensitizers, underscoring the ability of engineered enzymes to control the fate of excited-state intermediates.
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May 2025
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B22-Multimode InfraRed imaging And Microspectroscopy
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Abstract: The removal of SO2 from flue gas remains a challenge. Adsorption-based separation of SO2 using porous materials has been proposed as a more energy-efficient and cost-effective alternative to more traditional methods such as cryogenic distillations. Here we report a flexible hydrogen-bonded organic framework (HOF-NKU-1) that enables the sieving of SO2 through the guest-adaptive response and shape-memory effect of the material. HOF-NKU-1 exhibits a high selectivity of 7,331 for the separation of SO2/CO2 and a high SO2 storage density of 3.27 g cm−3 within the pore space at ambient conditions. The hydrophobic nature of HOF-NKU-1 enables high dynamic SO2 uptake and SO2 recovery, even in conditions of 95% humidity. The SO2/CO2 separation mechanism is studied through combinatorial gas sorption isotherms, breakthrough experiments and single-crystal diffraction studies, paving the way for the development of multifunctional shape-memory porous materials in the future.
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Feb 2025
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I04-1-Macromolecular Crystallography (fixed wavelength)
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K.-Y. M.
Chen
,
J. K.
Lai
,
L. S. P.
Rudden
,
J.
Wang
,
A. M.
Russell
,
K.
Conners
,
M. E.
Rutter
,
B.
Condon
,
F.
Tung
,
L.
Kodandapani
,
B.
Chau
,
X.
Zhao
,
J.
Benach
,
K.
Baker
,
E. J.
Hembre
,
P.
Barth
Diamond Proposal Number(s):
[14323]
Open Access
Abstract: Protein catalysis and allostery require the atomic-level orchestration and motion of residues and ligand, solvent and protein effector molecules. However, the ability to design protein activity through precise protein–solvent cooperative interactions has not yet been demonstrated. Here we report the design of 14 membrane receptors that catalyse G protein nucleotide exchange through diverse engineered allosteric pathways mediated by cooperative networks of intraprotein, protein–ligand and –solvent molecule interactions. Consistent with predictions, the designed protein activities correlated well with the level of plasticity of the networks at flexible transmembrane helical interfaces. Several designs displayed considerably enhanced thermostability and activity compared with related natural receptors. The most stable and active variant crystallized in an unforeseen signalling-active conformation, in excellent agreement with the design models. The allosteric network topologies of the best designs bear limited similarity to those of natural receptors and reveal an allosteric interaction space larger than previously inferred from natural proteins. The approach should prove useful for engineering proteins with novel complex protein binding, catalytic and signalling activities.
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Jan 2025
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[29890]
Open Access
Abstract: The creation of hosts capable of accommodating different guest molecules may enable these hosts to play useful roles in chemical purifications, among other applications. Metal–organic cages are excellent hosts for various guests, but they generally incorporate rigid structural units that hinder dynamic adaptation to specific guests. Here we report a conformationally adaptable pseudo-cubic cage that can dynamically increase its cavity volume to fit guests with differing sizes. This pseudo-cube incorporates a tetramine subcomponent with 2,6-naphthalene arms that cooperatively adopt a non-planar conformation, enabling the cage faces to switch between endo and exo states. A wide range of guest molecules were observed to bind within the cavity of this cage, spanning a range of sizes from 46% to 154% of the cavity volume of the empty cage. Experimental and computational evidence characterizes the flipping of cage faces from endo to exo, expanding the cavity upon binding of larger guests.
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Jan 2025
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Krios I-Titan Krios I at Diamond
Krios II-Titan Krios II at Diamond
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Alexander T.
Bakker
,
Ioli
Kotsogianni
,
Mariana
Avalos
,
Jeroen M.
Punt
,
Bing
Liu
,
Diana
Piermarini
,
Berend
Gagestein
,
Cornelis J.
Slingerland
,
Le
Zhang
,
Joost J.
Willemse
,
Leela B.
Ghimire
,
Richard J. H. B. N.
Van Den Berg
,
Antonius P. A.
Janssen
,
Tom H. M.
Ottenhoff
,
Constant A. A.
Van Boeckel
,
Gilles P.
Van Wezel
,
Dmitry
Ghilarov
,
Nathaniel I.
Martin
,
Mario
Van Der Stelt
Diamond Proposal Number(s):
[33054]
Open Access
Abstract: Bacteria have evolved resistance to nearly all known antibacterials, emphasizing the need to identify antibiotics that operate via novel mechanisms. Here we report a class of allosteric inhibitors of DNA gyrase with antibacterial activity against fluoroquinolone-resistant clinical isolates of Escherichia coli. Screening of a small-molecule library revealed an initial isoquinoline sulfonamide hit, which was optimized via medicinal chemistry efforts to afford the more potent antibacterial LEI-800. Target identification studies, including whole-genome sequencing of in vitro selected mutants with resistance to isoquinoline sulfonamides, unanimously pointed to the DNA gyrase complex, an essential bacterial topoisomerase and an established antibacterial target. Using single-particle cryogenic electron microscopy, we determined the structure of the gyrase–LEI-800–DNA complex. The compound occupies an allosteric, hydrophobic pocket in the GyrA subunit and has a mode of action that is distinct from the clinically used fluoroquinolones or any other gyrase inhibitor reported to date. LEI-800 provides a chemotype suitable for development to counter the increasingly widespread bacterial resistance to fluoroquinolones.
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Jun 2024
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B07-B1-Versatile Soft X-ray beamline: High Throughput ES1
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Ziyu
Cen
,
Xue
Han
,
Longfei
Lin
,
Sihai
Yang
,
Wanying
Han
,
Weilong
Wen
,
Wenli
Yuan
,
Minghua
Dong
,
Zhiye
Ma
,
Fang
Li
,
Yubin
Ke
,
Juncai
Dong
,
Jin
Zhang
,
Shuhu
Liu
,
Jialiang
Li
,
Qian
Li
,
Ningning
Wu
,
Junfeng
Xiang
,
Hao
Wu
,
Lile
Cai
,
Yanbo
Hou
,
Yongqiang
Chen
,
Luke L.
Daemen
,
Anibal J.
Ramirez-Cuesta
,
Pilar
Ferrer
,
David C.
Grinter
,
Georg
Held
,
Yueming
Liu
,
Buxing
Han
Diamond Proposal Number(s):
[33962]
Open Access
Abstract: Conversion of plastic wastes to valuable carbon resources without using noble metal catalysts or external hydrogen remains a challenging task. Here we report a layered self-pillared zeolite that enables the conversion of polyethylene to gasoline with a remarkable selectivity of 99% and yields of >80% in 4 h at 240 °C. The liquid product is primarily composed of branched alkanes (selectivity of 72%), affording a high research octane number of 88.0 that is comparable to commercial gasoline (86.6). In situ inelastic neutron scattering, small-angle neutron scattering, solid-state nuclear magnetic resonance, X-ray absorption spectroscopy and isotope-labelling experiments reveal that the activation of polyethylene is promoted by the open framework tri-coordinated Al sites of the zeolite, followed by β-scission and isomerization on Brönsted acids sites, accompanied by hydride transfer over open framework tri-coordinated Al sites through a self-supplied hydrogen pathway to yield selectivity to branched alkanes. This study shows the potential of layered zeolite materials in enabling the upcycling of plastic wastes.
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Apr 2024
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