A rotational-invariant metric for molecules computable from cryo-EM images

Single particle electron cryo-microscopy (cryo-EM) enables high-resolution reconstruction of 3-D biological macromolecules from a large collection of noisy and randomly oriented projection images. One notable approach to 3-D reconstruction, known as Kam’s method, exploits the computation of moments of these images. In this talk, I present a novel metric based on Kam's method that is invariant to both rotations and reflections, can be calculated without 3-D alignment, and does not assume a uniform distribution of viewing angles. This metric also delves into the capabilities and limitations of Kam's method in discriminating between molecules.