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bioRxiv · 10.64898/2026.08.06.743412

MC-Bayes: A Python-based wrapper for MotionCor3 processing of EER files compatible with Bayesian polishing

Burton-Smith, R. N.·Murata, K.
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Abstract

Here, we present MC-Bayes, a Python-based script for processing cryo-electron microscopy EER movies on one or more GPUs using MotionCor3 in a user-friendly manner. Further, it generates the .star files necessary for RELION to perform Bayesian polishing (a.k.a.: reference-based motion correction) with EER movies. Until now, Bayesian polishing of EER data was only possible if the CPU-based "RELIONCor" implementation of MotionCor2 was used, which is sub-optimal on GPU-heavy cryo-EM processing systems. This wrapper was created for those facilities and/or users who may have (many) powerful GPUs, but for whatever reason have few CPU cores or less system RAM. Leveraging MotionCor3, MC-Bayes allows motion correction of EER data 2 or more times faster (depending on system) than the RELION CPU implementation, except in circumstances where dozens or hundreds of CPU cores with high quantities of system RAM can be utilised.

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Burton-Smith, R. N., Murata, K.. 2026-08-07. MC-Bayes: A Python-based wrapper for MotionCor3 processing of EER files compatible with Bayesian polishing. https://doi.org/10.64898/2026.08.06.743412

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