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Open Access
Abstract: Advancements in macromolecular crystallography, driven by improved sources and cryocooling techniques, have enabled the use of increasingly smaller crystals for structure determination, with microfocus beamlines now widely accessible. Initially developed for challenging samples, these techniques have culminated in advanced beamlines such as VMXm. Here, an in vacuo sample environment improves the signal-to-noise ratio in X-ray diffraction experiments, and thus enables the use of submicrometre crystals. The advancement of techniques such as microcrystal electron diffraction (MicroED) for atomic-level insights into charged states and hydrogen positions, along with room-temperature crystallography to observe physiological states via serial crystallography, has driven a resurgence in the use of microcrystals. Reproducibly preparing small crystals, especially from samples that typically yield larger crystals, requires considerable effort, as no one singular approach guarantees optimal crystals for every technique. This review discusses methods for generating such small crystals, including mechanical crushing and batch crystallization with seeding, and evaluates their compatibility with microcrystal data-collection modalities. Additionally, we examine sample-delivery methods, which are crucial for selecting appropriate crystallization strategies. Establishing reliable protocols for sample preparation and delivery opens new avenues for macromolecular crystallography, particularly in the rapidly progressing field of time-resolved crystallography.
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May 2025
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I12-JEEP: Joint Engineering, Environmental and Processing
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Ilaria
Quaratesi
,
Ioan
Călinescu
,
Petre
Chipurici
,
Elisa-Gabriela
Dumbravă
,
Andrei
Cucos
,
Mohamed Yassine
Zaki
,
Pellegrino
La Manna
,
Adrian
Bercea
,
Miruna Silvia
Stan
,
Stefan
Michalik
,
Chloe
Pearce
,
Marianne
Odlyha
,
Genoveva
Burca
,
Elena
Badea
Diamond Proposal Number(s):
[35634]
Open Access
Abstract: This study presents an ultrasound-assisted synthesis of β-cyclodextrin/hydroxyapatite composites to be used as green and safe auxiliaries in the tanning process. A combination of spectroscopic and non-spectroscopic techniques such as DLS (dynamic light scattering), ZP (zeta potential), XRD (X-ray diffraction), SEM (scanning electron microscopy) and ATR-FTIR (attenuated total reflectance-Fourier transform infrared spectroscopy) were used to thoroughly characterize the eight composites obtained by varying the ultrasound process parameters. While not cytotoxic, all composites had strong antibacterial action against Brevibacterium lines, Staphylococcus aureus, Escherichia coli, and Staphylococcus epidermis. All composites underwent lab-scale tanning tests, but only those exhibiting the most suitable set of tanning abilities underwent pilot-scale testing. The composites' interaction with the collagen matrix was assessed by micro-DSC (micro-differential scanning calorimetry), TG/DTG/DTA (thermal analysis), 1H unilateral NMR (proton nuclear magnetic resonance), ATR-FTIR, in-situ temperature synchrotron-based XRD and standard tests (UNI EN ISO 3380: 2015, UNI EN ISO 2589: 2016, UNI EN ISO 105- B02:2014). Thermal stability, dye penetration, thickness, colour fastness, surface appearance and microbiological protection were all improved for the leather treated with a small amount of composite added to the wet finish float. These findings demonstrate the benefits of β-cyclodextrin/hydroxyapatite composites as safe and sustainable tanning additives.
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Apr 2025
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Krios V-Titan Krios V at Diamond
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Bin
Yang
,
Durga
Devalla
,
Silvia
Sonzini
,
Mikael
Boberg
,
Sashi
Gopaul
,
Monika
Sundqvist
,
Iain
Grant
,
Christopher
Jones
,
Stephanie
Brookes
,
Cindy
Weidauer
,
Eleonora
Paladino
,
Najet
Mahmoudi
,
Jason
Van Rooyen
,
Ana Gomes
Dos Santos
,
Johanna
Laru
,
Andy
Campbell
,
Lutz
Jermutus
,
Annette
Bak
Diamond Proposal Number(s):
[31098, 37220]
Abstract: Cotadutide (Cota) is a lipidated dual GLP-1 and Glucagon receptor agonist that was investigated for the treatment of various metabolic diseases, it is designed for once daily subcutaneous (SC) administration. Invasive daily injections can result in poor patient compliance with chronic disease, and here, we demonstrate an innovative strategy of encapsulating reversible cota self-assembled fibers within an in-situ forming depot of low molecular weight poly(lactic-co-glycolic) acid (LWPLGA) for sustained delivery GLP-1 and Glucagon receptor agonist with controlled burst release. This could be a suitable alternative to other sustained delivery strategies for fibrillating peptides. We investigated a range of cationic ions (Na+, Ca2+, Zn2+) and studied their influence on the secondary structure, morphology and the monomer release profile of cota fibers. Fibers forming hierarchy structures such as twisted filament and ribbons with beta sheet secondary structure resulted in better controlled burst. The subcutaneous administration of Ca2+ fiber/LWPLGA depot formulation in rats resulted in 60-fold reduction in maximum concentration (Cmax) compared with cota immediate release (IR) SC formulation and a prolonged plasma exposure over a month with plasma half-life extended from the 10 h observed with the cota daily formulation to 100 h. This extended-release formulation also maintains smaller peak and trough fluctuation within therapeutic window, and PK modelling of repeated dose indicates this formulation could enable a possible dose frequency of 14 days in rat with assumed therapeutic concentration (ratios of the maximum concentration and the trough concentration) Cmax/Ctrough window. This new long-acting injectable (LAI) method could open the door to transforming short-life peptides with sub-optimal half-life into candidates for weekly or even monthly dosing regimens, potentially leading to novel drug products with increased patient comfort.
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Apr 2025
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I19-Small Molecule Single Crystal Diffraction
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Diamond Proposal Number(s):
[30375]
Abstract: We present a combined experimental and density functional theory study that characterizes the charge and spin density in NiX2(3,5-lutidine)4 (X = Cl, Br and I). In this material, magnetic exchange interactions occur via Ni2+–halide⋯halide–Ni2+ pathways, forming one-dimensional chains. We find evidence for weak halide⋯halide covalency in the iodine system, which is greatly reduced when X = Br and is absent for X = Cl; this is consistent with the reported `switching-on' of magnetic exchange in the larger-halide cases. Our results are benchmarked against density functional theory calculations on [NiHF2(pyrazine)2]SbF6, in which the primary magnetic exchange is mediated by F–H–F bridging ligands. This comparison indicates that, despite the largely depleted charge density found at the centre of halide⋯halide bonds, these through-space interactions can support strong magnetic exchange gated by weak covalency and enhanced by significant electron density overlapping that of the transition metal centres.
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Apr 2025
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I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[26767]
Open Access
Abstract: Lithium ion batteries are pivotal for clean energy storage and mitigating climate change. In this study, we employ operando synchrotron X-ray computed tomography to investigate the dynamic evolution of battery cathode microstructure. We focus on tracking changes in porosity and pore size distribution at the microscale and cathode thickness at the macroscale during the lithiation and delithiation processes within a commercially configured battery. Image quality was enhanced using both conventional image processing methods and a Super-Resolution Convolutional Neural Network (SRCNN) model. Our findings revealed a slight increase in the cathode solid volume fraction and specific surface area as the battery transitioned from its pristine state to fully lithiated, followed by a reduction during delithiation. This behavior was attributed to the expansion of the cathode material and phase transitions during lithiation, which split larger pores into smaller ones, as evidenced by the increase in surface area. Cathode thickness also exhibited expansion during lithiation and contraction during delithiation. These results offer valuable insights into the structural changes that contribute to battery aging, helping researchers better understand how these different parameters change over time. This understanding is crucial for designing more durable and sustainable batteries in the future, both in terms of specific design and material selection, to enhance resistance during charge and discharge cycles to improve performance and longevity.
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Apr 2025
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B21-High Throughput SAXS
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Saishree S.
Iyer
,
Fangrui
Chen
,
Funso E.
Ogunmolu
,
Shoeib
Moradi
,
Vladimir A.
Volkov
,
Emma J.
Van Grinsven
,
Chris
Van Hoorn
,
Jingchao
Wu
,
Nemo
Andrea
,
Shasha
Hua
,
Kai
Jiang
,
Ioannis
Vakonakis
,
Mia
Potočnjak
,
Franz
Herzog
,
Benoît
Gigant
,
Nikita
Gudimchuk
,
Kelly E.
Stecker
,
Marileen
Dogterom
,
Michel O.
Steinmetz
,
Anna
Akhmanova
Diamond Proposal Number(s):
[21035]
Open Access
Abstract: Centrioles are microtubule-based organelles required for the formation of centrosomes and cilia. Centriolar microtubules, unlike their cytosolic counterparts, are stable and grow very slowly, but the underlying mechanisms are poorly understood. Here, we reconstituted in vitro the interplay between the proteins that cap distal centriole ends and control their elongation: CP110, CEP97, and CPAP/SAS-4. We found that whereas CEP97 does not bind to microtubules directly, CP110 autonomously binds microtubule plus ends, blocks their growth, and inhibits depolymerization. Cryo-electron tomography revealed that CP110 associates with the luminal side of microtubule plus ends and suppresses protofilament flaring. CP110 directly interacts with CPAP, which acts as a microtubule polymerase that overcomes CP110-induced growth inhibition. Together, the two proteins impose extremely slow processive microtubule growth. Disruption of CP110–CPAP interaction in cells inhibits centriole elongation and increases incidence of centriole defects. Our findings reveal how two centriolar cap proteins with opposing activities regulate microtubule plus-end elongation and explain their antagonistic relationship during centriole formation.
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Mar 2025
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B21-High Throughput SAXS
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Diamond Proposal Number(s):
[32486]
Open Access
Abstract: Lipoic acid is a biocompatible compound with antioxidant activity that is of considerable interest in cosmetic formulations, and the disulfide group in the N-terminal ring confers redox activity. Here, we study the self-assembly and aspects of the bioactivity of a lipopeptide (peptide amphiphile) comprising the KTTKS collagen-stimulating pentapeptide sequence conjugated to an N-terminal lipoic acid chain, lipoyl-KTTKS. Using SAXS, SANS and cryo-TEM, lipoyl-KTTKS is found to form a population of curly fibrils (wormlike micelles) above a critical aggregation concentration. Upon chemical reduction, the fibrils (and β-sheet structure) are disrupted because of the breaking of the disulfide bond, which produces dihydrolipoic acid. Lipoyl-KTTKS also undergoes photo-degradation in the presence of UV radiation. Through cell assays using fibroblasts, we found that lipoyl-KTTKS has excellent cytocompatibility across a wide concentration range, stimulates collagen production, and enhances the rate of cell coverage in a simple in vitro scratch assay of ‘wound healing’. Lipoyl-KTTKS thus has several notable properties that may be useful for the development of cosmetics, cell scaffolds or tissue engineering materials.
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Mar 2025
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Abstract: α-actinin (ACTN) is a pivotal member of the actin-binding protein family, crucial for the anchoring and organization of actin filaments within the cytoskeleton. Four isoforms of α-actinin exist: two non-muscle isoforms (ACTN1 and ACTN4) primarily associated with actin stress fibers and focal adhesions, and two muscle-specific isoforms (ACTN2 and ACTN3) localized to the Z-disk of the striated muscle. Although these isoforms share structural similarities, they exhibit distinct functional characteristics that reflect their specialized roles in various tissues. Genetic variants in α-actinin isoforms have been implicated in a range of pathologies, including cardiomyopathies, thrombocytopenia, and non-cardiovascular diseases, such as nephropathy. However, the precise impact of these genetic variants on the α-actinin structure and their contribution to disease pathogenesis remains poorly understood. This review provides a comprehensive overview of the structural and functional attributes of the four α-actinin isoforms, emphasizing their roles in actin crosslinking and sarcomere stabilization. Furthermore, we present detailed structural modeling of select ACTN1 and ACTN2 variants to elucidate mechanisms underlying disease pathogenesis, with a particular focus on macrothrombocytopenia and hypertrophic cardiomyopathy. By advancing our understanding of α-actinin’s role in both normal cellular function and disease states, this review lays the groundwork for future research and the development of targeted therapeutic interventions.
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Mar 2025
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I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[30413]
Abstract: The migration and deposition of fine particles in porous materials is critical in industries such as energy, pharmaceuticals, and environmental engineering. Using 3D time-lapse synchrotron X-ray imaging, we observe fine particles invading porous media, analyzing the effects of pore size and heterogeneity at both pore and macro scales. Glass beads model homogeneous and heterogeneous conditions, revealing a sequence of deposition processes: surface attachment, throat bridging, blocking, pore filling, compaction, and migration. A critical throat-to-particle size ratio of 1.7 governs deposition behavior. At the macro-scale, heterogeneities like beddings and flow pathways influence fines migration and deposition. Based on dynamic 3D imaging, we propose a mechanism for fines behavior in heterogeneous porous media. These findings enhance understanding of fines migration, offering a predictive framework for managing formation damage and optimizing filter cake design in drilling and clean energy applications.
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Mar 2025
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I15-Extreme Conditions
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Diamond Proposal Number(s):
[30553]
Open Access
Abstract: BiFeO3-BaTiO3 (BF-BT) solid solutions have great potential as high-temperature piezoelectric transducers and energy storage dielectrics. However, the effects of donor doping in BF-BT on the local chemical heterogeneity and corresponding control of ferroelectric properties are not well investigated. In this study, it is shown that substitution of Nb5+ for Fe3+ at a concentration of only 0.1 at% in 0.75BF-0.25BT ceramics can induce pronounced core-shell microstructural features, which are not evident for pure BF-BT ceramics or those doped with 0.1 at% Nb5+ for Ti4+. The spatial distribution of Nb, confirmed by Nano-SIMS with exceptional resolution and sensitivity, reveals the role of Nb as an aliovalent solute that inhibits chemical homogenization, stabilizing the formation of Bi-, Fe-enriched core and Ba-, Ti-enriched shell regions at high temperatures, and reducing inter-diffusion during sintering. Electric field-induced domain switching and lattice strain measurements, obtained by in-situ high-energy synchrotron X-ray diffraction, revealed the effects of elastic constraint between the core and shell regions, which degraded the dielectric, ferroelectric, and piezoelectric properties. In contrast, substitution of 0.1 at% Nb on the Ti4+ site gave rise to more homogeneous materials and induced a softening effect with enhanced functional properties. This study provides an advanced investigation into the effects of trace amounts of donor dopant in BF-BT ceramics and offers valuable insights into optimizing doping strategy to control their microstructure and functional properties.
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Mar 2025
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