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arXiv · 2401.15183

Moment-based metrics for molecules computable from cryo-EM images

Andy Zhang·Oscar Mickelin·Joe Kileel·Eric J. Verbeke·Nicholas F. Marshall·Marc Aurèle Gilles·Amit Singer
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Abstract

Single particle cryogenic electron microscopy (cryo-EM) is an imaging technique capable of recovering the high-resolution 3-D structure of biological macromolecules from many noisy and randomly oriented projection images. One notable approach to 3-D reconstruction, known as Kam's method, relies on the moments of the 2-D images. Inspired by Kam's method, we introduce a rotationally invariant metric between two molecular structures, which does not require 3-D alignment. Further, we introduce a metric between a stack of projection images and a molecular structure, which is invariant to rotations and reflections and does not require performing 3-D reconstruction. Additionally, the latter metric does not assume a uniform distribution of viewing angles. We demonstrate uses of the new metrics on synthetic and experimental datasets, highlighting their ability to measure structural similarity.

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Andy Zhang, Oscar Mickelin, Joe Kileel, Eric J. Verbeke, Nicholas F. Marshall, Marc Aurèle Gilles, Amit Singer. 2024-01-26. Moment-based metrics for molecules computable from cryo-EM images. https://arxiv.org/abs/2401.15183

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