12th International Workshop on Radiation Damage to Biological Samples

3 Jun 2025, 12:00 → 5 Jun 2025, 14:00 Europe/Zurich

Auditorium (Paul Scherrer Institut)

Welcome to the home of the 
12^th International Workshop on Radiation Damage to Biological Samples.

The Workshop will address the essential questions and challenges of radiation damage to biological samples during their examination with ionizing radiation.

The workshop will cover various X-ray and electron scattering techniques, from crystallography to imaging, and offers ample opportunities for information exchange and discussion among researchers from around the globe.

Important dates:

• Registration opens: 06.01.2025
• Registration closes: 14.04.2025
• Abstract submission opens: 06.01.2025
• Abstract submission closes: 14.04.2025

 

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abstract_template_rd12.docx

RD12_Poster_02-2025.pdf

Tuesday 3 June

Catering: Registarion & Welcome Lunch

General: Welcome and Introduction

Convener: Elspeth GARMAN (University of Oxford)

Radiation Damage in Electron Crystallography and Microscopy

1 Radiation damage in recent MicroED measurements

Microcrystal electron diffraction (MicroED) involves collecting a sequence of diffraction images from a continuously rotating microcrystal in a transmission electron microscope. Due to the small size of these crystals, the resulting diffraction patterns typically feature weak, low-intensity spots. Recent advances in direct electron-counting detectors have significantly improved signal detection, enabling high-quality data collection at lower electron fluence. This not only shortens acquisition times but also mitigates radiation damage to the sample. Additionally, the introduction of energy filtering has enhanced the accuracy of high-resolution reflection integration without increasing the dose delivered to the sample. In this presentation, we will review early results from radiation damage studies on cryo-cooled crystals of model proteins and highlight recent methodological improvements in MicroED.

Speaker: Johan HATTNE (UCLA)

2 Extending the reach of single-particle cryoEM

Ten years on from the “resolution revolution”, molecular structure determination using electron cryomicroscopy (cryoEM) is poised in 2025 or early 2026 to surpass X-ray crystallography as the most used method for experimentally determining new structures [1]. But the technique has not reached the physical limits set by radiation damage and the signal-to-noise ratio in individual images of molecules. By examining these limits and recent work on radiation damage to biological molecules at different temperatures [2,3] and energies [4,5], I will identify opportunities for extending the application of single-particle cryoEM to smaller, larger and more difficult structures, and into specimens taken directly from vitrified cells. This will help guide technology development to continue the exponential growth of structural biology in the coming decade.

References
[1] A. Patwardhan, R. Henderson, C.J. Russo, Extending the reach of single-particle cryoEM, COSB in press (2025).
[2] K. Naydenova, A. Kamegawa, M. J. Peet, R. Henderson, Y. Fujiyoshi, C. J. Russo, On the reduction in the effects of radiation damage to two-dimensional crystals of organic and biological molecules at liquid-helium temperature, Ultramicroscopy 237 (2022) 113512.
[3] J. L. Dickerson, K. Naydenova, M. J. Peet, H. Wilson, B. Nandy, G. McMullan, R. Morrison, C. J. Russo. Reducing the effects of radiation damage in cryo-EM using liquid helium temperatures. PNAS 2025
[4] M.J. Peet R. Henderson C.J. Russo, The energy dependence of contrast and damage in electron cryomicroscopy of biological molecules, Ultramicroscopy 203 (2019) 125–131.
[5] G. McMullan et al. Structure determination by cryoEM at 100 keV. PNAS 120 (2023) e2312905120.

Speaker: Christopher J. RUSSO (MRC Cambridge)

3 TEM and STEM Imaging of Radiation-Sensitive Samples

Beam damage to biological specimens is more troublesome in the TEM than in x-ray imaging (where the spatial resolution is more modest) despite the stronger diffraction signal provided by electrons [1]. One solution has been to treat tissue (and other) specimens with heavy-metal stain but the preference is to use unstained samples and phase contrast, while cooling the sample to reduce damage (cryo-EM).
Whereas the electron optics of a TEM can provide atomic-scale contrast, the image resolution for a beam-sensitive sample is usually limited by the effects of radiolysis. The signal/noise ratio (SNR) in the image is then determined by beam-electron shot noise and the damage-limited resolution is given [2] by

(1) $\mathrm{DLR }=(\mathrm{SNR})C^{-1}[(\mathrm{DQE})F D_{c}]^{{-\frac{1}{2}}}$

Optimizing resolution involves paying attention to each term in Eq. (1). SNR is usually taken as 3 or 5 (the Rose criterion) but a large improvement is possible if there are multiple copies of the same object, as in diffraction imaging or single-particle analysis (SPA). The image contrast C is high in dark-field mode but for thin samples the electron-collection efficiency F is low. Phase contrast is efficient but is problematic for thicker samples, as required for most tomographic (3-dimensional) imaging. The detective quantum efficiency (DQE) of the electron detector can be maximized by using direct recording, rather than employing a scintillator.
The characteristic dose Dc represents the maximum fluence that the specimen can withstand before the structure being observed is degraded. Dc can be increased by cooling the sample with liquid nitrogen or liquid helium [3] or by coating it with an evaporated layer, and graphene encapsulation seems to be even more effective
Dose rate seems to have little effect on the radiolysis damage to organic specimens, except for secondary effects (mass loss) at a low specimen temperature and at the high dose rates (>1015 Gy/s) possible in scanning-mode TEM (STEM). Unlike XFEL x-ray imaging, it will likely remain impossible to outrun the primary stage of damage with electrons, due to their electrostatic repusion. Earlier reports of two-fold damage reduction using femtosecond electron pulses have recently been disputed [4].

References
[1] Henderson, R. (1995) Q. Rev. Biophys., 28, 171-193.
[2] Egerton, R.F. (2024) Micron, 177, 103576.
[3] Naydenova, K. et al. (2022) Ultramicroscopy, 237, 113512.
[4] Zhao, Y. et al. (2024) bioRxiv preprint: https://10.1101/2024.12.20.629524

Speaker: Ray EGERTON (University of Alberta)

4 A Physical Theory For Cryo-EM at Liquid-Helium Temperatures

The benefits of reducing the data collection temperature for electron cryomicroscopy (cryo-EM) from liquid-nitrogen temperatures to liquid-helium temperatures have been debated over many years. A physical theory of dose-dependent information loss in cryo-EM was presented for imaging vitrified aqueous biological specimens at liquid-nitrogen temperatures [1], but extending this to liquid-helium temperatures is needed. Previously, it was demonstrated that there is a 1.2–1.8x reduction in radiation damage for 2D protein crystals when imaging at temperatures near liquid helium [2]⁠. Unfortunately, lowering specimen temperatures for cryo-EM of macromolecules embedded in vitreous ice has consistently proven to be no better than liquid-nitrogen temperatures and is often worse [3]. We aimed to determine whether the reduction in radiation damage measured in 2D crystals extends to single-particle cryo-EM and, if so, what else could be limiting data quality.
Consequently, we investigated several dose-dependent physical phenomena that could limit single-particle cryo-EM data quality: radiation damage, microscopic charge fluctuations, charge accumulation, pseudo-Brownian motion of water, mass loss, hydrogen bubbling, and beam-induced motion. We found that radiation damage is reduced by a similar amount for single-particle cryo-EM as was measured by 2D crystallography. We demonstrate that the reduction in data quality is likely caused by beam-induced motion, with all other physical phenomena that we measured being either unchanged or not sufficient to cause a reduction in image quality at lower specimen temperatures. Using novel specimen supports, we have been able to eliminate this beam-induced motion and determined cryo-EM structures at liquid-helium temperatures where every frame carries more information compared to the equivalent at liquid-nitrogen temperatures [4]. Alongside the development of new TEMs capable of operating at temperatures below liquid-nitrogen, this theory will enable cryo-EM to resolve smaller molecules than is currently possible.

References
[1] R. Henderson, C. J. Russo, Single Particle CryoEM: Potential for Further Improvement, Microscopy and Microanalysis 25 (S2) (2019) 4–5.
[2] K. Naydenova, A. Kamegawa, M. J. Peet, R. Henderson, Y. Fujiyoshi, C. J. Russo, On the reduction in the effects of radiation damage to two-dimensional crystals of organic and biological molecules at liquid-helium temperature, Ultramicroscopy 237 (2022) 113512.
[3] O. Pfeil-Gardiner, D. J. Mills, J. Vonck, W. Kuehlbrandt, A comparative study of single-particle cryo-EM with liquid-nitrogen and liquid-helium cooling, IUCrJ 6 (6) (2019) 1099–1105.
[4] J. L. Dickerson, K. Naydenova, M. J. Peet, H. Wilson, B. Nandy, G. McMullan, R. Morrison, C. J. Russo. Reducing the effects of radiation damage in cryo-EM using liquid helium temperatures. PNAS 2025

Speaker: Joshua DICKERSON (UC Berkeley)

Catering: Coffee

Damage at New Sources - XFELs and 4th Generation Synchrotrons

Convener: Nadja ZATESPIN

5 Investigation of radiation damage in room temperature serial macromolecular crystallography at a fourth generation Synchrotron

Radiation damage is major concern in macromolecular crystallography (MX) where ionising X-rays used for structure determination can result in a cascade of damaging processes caused by the absorption of energy (denoted mainly as dose: absorbed energy/mass (J/kg; Gray (G)) and radiolysis of molecules. These can introduce artefacts within the structure (specific damage) and the overall data (global damage). Collection at cryogenic temperatures (100 K) is normally performed to mitigate the effects of radiation damage but recently there has been a resurgence in room temperature (RT) and serial crystallography collection. Serial synchrotron crystallography (SSX), with approaches adopted from X-ray free electrons lasers (XFELs), provides a suitable way to collect RT data at synchrotrons with reduced radiation damage by spreading the total dose over thousands of individual microcrystals. This usually relies on a microfocus beamline and a very low-dose per crystal collection strategy to compensate.

With advancements in technologies, synchrotrons are now being upgraded or constructed to fourth generation light sources, offering much higher brilliance compared to their predecessors, and, consequently, microfocus MX beamlines with increased flux density are becoming more routinely available offering much higher dose rates for RT-SSX collection. One example of this is ID29, the flagship beamline constructed at the high-energy fourth generation European Synchrotron Radiation Facility (ESRF), following its upgrade to the Extremely Brilliant Source (ESRF-EBS) [Raimondi et al, 2023]. ID29 is currently in unique territory, delivering slightly polychromatic (1% ΔE/E) microsecond X-ray pulses (90 µs) with a flux density of > 1014 ph/s/µm2, three times higher than third generation sources, and with dose rates on the order of several GGy/s. The unique beam characteristics on ID29 allow for the possibility of serial microsecond crystallography (SµX) for the structure determination of macromolecules using RT-SSX [Orlans et al, 2025]. As ID29 is setting a precedent for similar beamlines that are appearing or due to appear worldwide, a comprehensive radiation damage analysis is thus required.

References
[1] Raimondi et al. (2023) Communications Physics, 6, 82.
[2] Orlans et al. (2025) Communications Chemistry, 8, 6.

Speaker: Samuel L. ROSE (ESRF)

Posters: Poster Blitz

Convener: Florian DWORKOWSKI (PSI - Paul Scherrer Institut)

Discussion

Catering: Dinner

Posters: Posters & Drinks

Wednesday 4 June

Biological Studies Affected by Radiation Damage

6 Rejuvenating online UV-Vis microspectrophotometry by monitoring dose- and time-resolved phenomena at both cryogenic and room temperature

The French protein crystallography beamline BM07-FIP2 at the ESRF enables both cryogenic and room-temperature studies on single crystals, with precise control over the deposited X-ray dose thanks to a large, homogeneous top-hat beam. [1] In addition, its sample environment allows for easy integration of the EMBL/ESRF microspectrophotometer [2], enabling in crystallo UV-Visible absorption and fluorescence measurements in parallel with X-ray diffraction. This approach has allowed for the monitoring of the evolution of the absorbance of metal centres, cofactors, or chromophores as a function of X-ray dose, providing real-time insights into both the extent of radiation damage and the functional state of macromolecules. This presentation will focus on recent methodological developments that led studying the extent of radiation damage on various proteins, enabling the comparison between room and cryogenic temperature. Finally, the plans for the future sample environment of BM07-FIP2 fully integrating an improved microspectrophotometer will be described.

References
[1] McCarthy A. et al. (2025) J Synchrotron Radiat., 32, in press.
[2] McGeehan J, Ravelli RB, Murray JW, Owen RL, Cipriani F, McSweeney S, Weik M, Garman EF. (2009) J Synchrotron Radiat., 16, 163-172.

Speaker: Sylvain ENGLIBERGE (IBS Grenoble)

Catering

Biological Studies Affected by Radiation Damage

7 Specific Radiation Damage to Halogenated Inhibitors and Ligands in Protein-Ligand Crystal Structures

Protein–inhibitor crystal structures aid medicinal chemists in efficiently improving the potency and selectivity of small-molecule inhibitors. It is estimated that a quarter of lead molecules in drug discovery projects are halogenated. Protein–inhibitor crystal structures have shed light on the role of halogen atoms in ligand binding. They form halogen bonds with protein atoms and improve shape complementarity of inhibitors with protein binding sites. However, specific radiation damage (SRD) can cause cleavage of carbon–halogen (C–X) bonds during X-ray diffraction data collection. This study shows significant C–X bond cleavage in protein–ligand structures of the therapeutic cancer targets B-cell lymphoma 6 (BCL6) and heat shock protein 72 (HSP72) complexed with halogenated ligands, which is dependent on the type of halogen and chemical structure of the ligand. The study found that metrics used to evaluate the fit of the ligand to the electron density deteriorated with increasing X-ray dose, and that SRD eliminated the anomalous signal from brominated ligands. A point of diminishing returns is identified, where collecting highly redundant data reduces the anomalous signal that may be used to identify binding sites of low-affinity ligands or for experimental phasing. Straightforward steps are proposed to mitigate the effects of C–X bond cleavage on structures of proteins bound to halogenated ligands and to improve the success of anomalous scattering experiments.

References
[1] Rodrigues, M.J., Cabry, C., Collie, G., Carter, M., McAndrew C., Owen, R.L., Bellenie, B.R., Le Bihan, Y-V., van Montfort, R.L.M. (2024) J. Appl. Cryst., 57, 1951-1965.

Speaker: Matthew J. RODRIGUES (Diamond)

8 A protein switch to bind different redox states in the cyanobacterial FutA iron binding protein revealed by an X-ray pump-probe approach

Radiation damage is a faithful attender to X-ray crystallographic studies of metallo-proteins. Thus, care is taken to limit the effects of radiation damage and avoid consequent misinterpretation of X-ray crystallographic results. In our study, we applied defined doses to selectively probe the redox states involved in metal binding.
We studied the cyanobacterial iron binding protein FutA, an ABC transporter substrate binding protein that can also act as an intracellular iron binding protein [1]. We determined crystallographic structures using X-ray and neutron radiation characterised as ferrous [Fe(II)] and ferric [Fe(III)] complexes [2]. These states are distinguished by protein conformation, particularly the positioning of the positively charged Arg203 side chain as part of the iron binding site in the [Fe(II)] complex.

We captured the transition between [Fe(III)] and [Fe(II)] states upon X-ray photoreduction with a dose series using a serial synchrotron crystallography fixed target approach, see panel A. Using a novel XFEL X-ray pump-probe approach, we uncovered how Arg203 functions as a molecular switch, enabling accommodation of different iron oxidation states, see panel B [2]. The switching capability of the single FutA protein provides functional insight and suggests genome streamlining, where the loss of specialised FutA variants may reflect ecological adaptation.

References
[1] Polyviou, D. et al. (2018) J. Biol. Chem., 293, 18099-18109.
[2] Bolton, R. et al. (2024) PNAS, 121, e2308478121.

Speaker: Ivo TEWS (University of Southampton)

1 (Indico).png

9 X-ray photoreduction of the active site copper in the fungal lytic polysaccharide monooxygenase LsAA9A

Lytic polysaccharide monooxygenases are enzymes [1] binding their active-site copper through the characteristic His-brace motif shown above including two His – one N-terminal – and often also a Tyr. The reaction cycle starts with reduction of the resting state Cu(II) to Cu(I) – in the laboratory usually using ascorbate as small molecule reductant. Despite the name, most LPMOs prefer hydrogen peroxide as co-substrate, to subsequently oxidatively cleave the glycosidic bonds in saccharides.
We have previously – through crystal cryo-structures of the model enzyme LsAA9A determined at high and low X-ray doses, and based on the hypothesis that X-ray induced photoreduction mimics natural priming reaction - reconstructed possible changes in geometry during the catalytic cycle and identified a small shortening of the Cu(II)-Tyr distance [2].
Aside from uncertainty on the biological significance of such shortening [3], we wanted to address concerns regarding the ability of macromolecular crystallography to reliably detect differences in the order of 0.1-0.2 Å. We thus carried out additional triplicate independent structure determination representing Cu(I)/Cu(II) states with/without the model substrates cellotriose, showing statistically significant differences only for the Cu(II)-Tyr distance with/without saccharide, but no other Cu-protein distance.
In order to assess whether additional general X-ray damage obscures similar shortening in the Cu(I) state induced by photoreduction, we are now comparing with cryo data collected after priming by chemical reduction with ascorbate at low X-ray doses.
Finally since X-ray-induced photoreduction of the active-site copper may closely approximate the chemical priming reaction, it holds potential as a trigger for time-resolved studies. To explore this possibility further, we are currently investigating the photoreduction process at room temperature.

References
[1] Tandrup, T., Frandsen, K.E.H., Johansen, K.S., Berrin, J.-G., Lo Leggio, L. (2018) Biochem. Soc. Trans. 46, 1431–1447
[2] Tandrup, T., Muderspach, S.J., Banerjee, S., Santoni, G., Ipsen, J.Ø., Hernández-Rollán, C., Nørholm, M.H.H., Johansen, K.S., Meilleur, F., Lo Leggio, L. (2022) IUCR Journal 9, 666-681.
[3] Wieduwilt, Lo Leggio and Hedegård (2024), Dalton Trans, 53, 5796-5807.

Speaker: Leila LO LEGGIO (University of Copenhagen)

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Catering: Lunch

General: Visit SLS2.0 and SwissFEL

Catering: Coffee

Radiation Damage in Complementary Fields including Biological Imaging

10 High-dose effects in high-resolution X-ray microscopy of soft materials

High-resolution X-ray microscopy is used as a complementary approach to electron microscopy for non-destructive imaging of soft materials, including biological tissues, e.g. frozen hydrated [1] or heavy metal stained resin-embedded [2] brain tissues. For this purpose, photon energies above about 2 keV are used to penetrate tissues of about 100 micron thickness or more, for which samples exhibit a very low contrast. To overcome this challenge, phase-contrast hard X-ray microscopy methods are typically used in synchrotron beamlines, reaching a resolution of about 100 nm. The available coherent flux and the changes in the sample structure due radiation are among the main challenges to improve spatial resolution in hard X-ray microscopy of soft materials. Next generation synchrotron sources provide high brilliance, which offers a great opportunity to improve resolution. However, this will require the development of new approaches to mitigate the effects of radiation in soft materials.

Here, we present our experience when applying ptychographic X-ray computed tomography (PXCT) [3] to soft materials. In polymer samples or resin-embedded biological tissues, we observe deformations, such as expansion or contraction of the sample, and mass loss above a certain X-ray dose exposure [4]. For samples that deform during acquisition, we apply a non-rigid tomographic reconstruction to recover the original 3D structure of the specimen [5]. For resin-embedded biological tissues, we have identified a resin which is more resistant to hard X-ray radiation compared to standard epoxy resins used for EM [4]. Finally, we explore acquisition strategies and sample preparation protocols that minimize the effect of radiation.

References
[1] Tran, T.T., et al. (2020) Front. Neurosci. 14, 570019.
[2] Kuan, A.T., et al. (2020) Nat. Neurosci. 23, 1637-1643.
[3] Dierolf, M., et al. (2010) Nature 467, 436-439.
[4] Bosch, C., et al. (2023) bioRxiv, doi: https://doi.org/10.1101/2023.11.16.567403.
[5] Odstrčil, M., et al. (2019) Nat. Commun. 10, 2600.

Speaker: Ana DIAZ (Paul Scherrer Institut)

11 Coherent X-rays Reveals Radiation-Induced Dynamics in Hydrated Proteins

Radiation damage remains a central challenge in structural biology, particularly when probing soft, disordered materials like hydrated proteins. In this presentation, I will discuss recent advances using X-ray Photon Correlation Spectroscopy (XPCS) to study radiation-driven dynamics in both hydrated protein powders [1] and dense protein solutions [2,3]. At cryogenic temperatures, we investigate lysozyme powders and find that X-ray exposure induces nanoscale stress relaxation, revealing a temperature-dependent transition around 227 K associated with enhanced dynamical heterogeneity. These results highlight how radiation can stimulate out-of-equilibrium processes in supercooled, granular biomaterials. At ambient temperatures, using megahertz XPCS at the European XFEL, we probe antibody and ferritin solutions as a function of X-ray dose and dose rate. Our measurements capture anomalous diffusion and aggregation dynamics, which are influenced by both hydrodynamic and direct protein interactions. Modeling these effects allows us to disentangle intrinsic molecular behavior from radiation-induced perturbations. Together, these studies underscore the dual role of coherent X-rays as both probe and stimulus, offering critical insights into how radiation impacts biological materials under experimentally relevant conditions. This understanding is essential for optimizing measurement strategies in next-generation X-ray facilities and for minimizing radiation effects in XPCS studies of biological samples.

References
[1] M. Bin et al., Coherent X-ray Scattering Reveals Nanoscale Fluctuations in Hydrated Proteins, J. Phys. Chem. B 127, 4922 (2023).
[2] M. Reiser et al., Resolving molecular diffusion and aggregation of antibody proteins with megahertz X-ray free-electron laser pulses, Nat. Commun. 13, 1 (2022).
[3] A. Girelli et al., Coherent X-Rays Reveal Anomalous Molecular Diffusion and Cage Effects in Crowded Protein Solutions, arXiv:2410.08873.

Speaker: Foivos PERAKIS (Stockholm University)

Discussion

General: Transfer to Brugg

Catering: Conference Dinner

Thursday 5 June

Pump-Laser Excitation Conditions in Time-Resolved Serial Femtosecond Crystallography

12 Ultrafast structural changes in myoglobin: influence of pump laser fluence

The high-intensity femtosecond pulses generated by X-ray free-electron lasers enable pump-probe studies of electronic- and nuclear changes during light-induced reactions. On time scales from femtoseconds to milliseconds and for a variety of biological systems, time-resolved serial femtosecond crystallography (TR-SFX) has provided detailed structural data on processes such as light-induced isomerization, breakage or formation of chemical bonds and electron transfer. However, to date, most if not all ultra-fast TR-SFX studies have employed such high pump laser energies that nominally, several photons were absorbed for each chromophore. As such multiphoton absorption processes may force the protein response into nonphysiological pathways, this is of considerable concern as it poses the question whether this experimental approach allows valid inferences to be drawn about biological processes, which are likely single-photon.
Here we describe an ultrafast pump-probe SFX study of the photodissociation of carboxymyoglobin, which shows that different pump laser fluences result in strikingly different dynamics. In particular, these concern the mechanistically important coherent oscillations of the Fe-CO bond distance (predicted by recent quantum wavepacket dynamics) which are seen to depend strongly on pump laser energy. While our results confirm both the feasibility of performing TR-SFX pump probe experiments in the linear photoexcitation regime, they also show the necessity of doing so. We propose this to be a starting point for the reassessment of the design and interpretation of ultrafast TR-SFX pump probe experiments, to ensure any emergent insights are biologically relevant.

Speaker: Thomas R.M. BARENDS (Max Planck Institute for Medical Research)

Catering: Coffee

Radiation Damage in Temperature Controlled Crystallography

13 Exploring Ligand-Protein Interactions at Multiple Temperatures Using Macromolecular Crystallography

Cryogenic temperatures may introduce artefacts that limit the understanding of protein dynamics, crucial to their biological functions. To address this, we developed a room-temperature (RT) X-ray crystallographic method that captures movie-like structural snapshots triggered by temperature [1]. This method revealed binding-mode changes of TL00150, a 175.15 Da fragment, in endothiapepsin. Building on this, we further developed Cryo2RT, a high-throughput RT data-collection method using cryo-cooled crystals, which leverages the cryo-crystallography workflow [2]. This method has been applied to endothiapepsin with four soaked fragments, thaumatin, and SARS-CoV-2 3CLpro, Cryo2RT uncovered distinct ligand-binding modes at RT, not seen at cryogenic temperatures. To minimize radiation damage, X-ray doses were controlled below 500 kGy, a threshold considered safe for both cryo and RT crystallography. Despite similar doses, RT datasets showed slightly lower resolution and higher B-factors (30–40 Ų vs. ~20 Ų at cryo), likely due to increased atomic motion at RT. These findings provide insights into structural interpretation at RT and highlight Cryo2RT's potential for fragment-based screening and studying temperature-dependent dynamics.

References
[1] Huang, C.-Y., Aumonier, S., Engilberge, S., Eris, D., Smith, K. M. L., Leonarski, F., Wojdyla, J. A., Beale, J. H., Buntschu, D., Pauluhn, A., Sharpe, M. E., Metz, A., Olieric, V., and Wang, M. (2022) Acta Cryst. D78: 964-974. https://doi.org/10.1107/S205979832200612X
[2]: Huang, C.-Y., Aumonier, S., Olieric, V., and Wang, M. (2024) Acta Cryst. D80: 620-628. https://doi.org/10.1107/S2059798324006697

Speaker: Chia-Ying HUANG (PSI - Paul Scherrer Institut)

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Discussion

General: Summary and Farewell

Convener: Martin WEIK (IBS)

Catering: Lunch and Farewell