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bioRxiv · 10.1101/2025.09.04.674375

A user-friendly goniometer-compatible fixed-target platform formacromolecular crystallography at synchrotrons

Ghosh, S.·Banacore, A.·Norder, P.·Bjelcic, M.·Kabbinale, A.·Nileshwar, P.·Wehlander, G.·de Sanctis, D.·Basu, S.·Orlans, J.·Vallejos, A.·M. G. Chavas, L.·Neutze, R.·Branden, G.
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Abstract

Fixed-target platforms provide convenient support for microcrystals during serial X-ray crystallography studies using synchrotron radiation. Here, we describe a simple, user-friendly 3D-printed support where the crystals are sandwiched between two layers of thin X-ray transparent membrane resulting in very low scattering background. The platform is compatible with magnetic mounting onto the standard goniometer of macromolecular crystallography beamlines. Our design utilizes a 96-well frame that facilitates hanging-drop experiments directly on the membrane using conventional crystallization plates, thereby eliminating multiple pipetting and crystal handling steps. Crystals can be enclosed into a sandwich and packed into cassettes, preventing the risk of the sample drying out during room-temperature transportation to synchrotron sources. The versatility of the platform is demonstrated by five structures solved using different crystallization- and data-collection strategies. Single crystal rotational-crystallography at both room- and cryogenic-temperatures using large crystals of lysozyme is shown. On-chip microcrystallization is illustrated by use of a photosynthetic reaction center as an example. Finally, serial crystallography data collection at room-temperature from microcrystals of photosynthetic reaction center as well as cytochrome c oxidase crystallized in lipidic cubic phase is presented.

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Ghosh, S., Banacore, A., Norder, P., Bjelcic, M., Kabbinale, A., Nileshwar, P., Wehlander, G., de Sanctis, D., Basu, S., Orlans, J., Vallejos, A., M. G. Chavas, L., Neutze, R., Branden, G.. 2025-09-07. A user-friendly goniometer-compatible fixed-target platform formacromolecular crystallography at synchrotrons. https://doi.org/10.1101/2025.09.04.674375

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