"Optimizing Cryo-EM with Square or Rectangular Beams for Enhanced Performance"

In the realm of cutting-edge cryogenic electron microscopy (cryo-EM), a groundbreaking innovation has recently taken the scientific community by storm. Imagine a world where the mysteries of cellular landscapes and macromolecules are unraveled at unprecedented resolutions and speeds, providing profound insights into the intricate workings of biological processes. This is made possible by the fusion of fringe-free illumination and aberration-free image shifts, creating a perfect storm for advancing single particle analysis (SPA) and cryo-electron tomography (cryo-ET).

However, a significant hurdle has long plagued automated cryo-EM data collection - the mismatch between the circular electron beam profile and the square or rectangular camera dimensions. This disconnect leads to a loss of over 36% of the exposed area during imaging, hindering the full potential of data acquisition. But fear not, as in a recent edition of Nature Methods, two groundbreaking studies have introduced a game-changing solution - the utilization of square or rectangular beams to harmonize with the camera's dimensions, revolutionizing data acquisition efficiency in both SPA and cryo-ET studies.

Enter Brown et al. and Chua et al., the trailblazers behind this innovative approach. Brown et al. etched square and rectangular apertures of various sizes and orientations onto a silicon wafer, ensuring that the beam aligns closely with the camera without the need for lens modifications. Meanwhile, Chua et al. installed aperture plates with square holes on the C2 aperture rod, adjusting the beam's rotation by fine-tuning the P2 lens strength.

The results were nothing short of astounding. The use of square or rectangular beams increased the acquisition area by over 70%, with resolutions matching those obtained with conventional round beams. Furthermore, the novel aperture designs showcased minimal aberrations and maintained image quality, opening the door to capturing a broader range of biological samples with exceptional detail.

But the innovation didn't stop there. Chua et al. elevated the impact of square beams by applying them to cryo-ET, presenting a novel acquisition scheme that minimized overexposure in adjoining areas during montage cryo-ET. By decoupling beam-image shift from sample tilt, their method ensured seamless tiling in large datasets, propelling the field of cryo-ET to new heights.

As we stand on the cusp of a new era in cryo-EM, the future looks brighter than ever. With square and rectangular beams paving the way for enhanced data acquisition efficiency and image quality, the possibilities are limitless. Imagine the secrets waiting to be unveiled, the boundaries waiting to be pushed. The world of cryo-EM stands on the brink of a revolution, and it all started with a simple yet ingenious idea - changing the shape of the beam.

So, buckle up and get ready to witness the extraordinary unfold before your eyes as cryo-EM's multishot potential is unleashed by square and rectangular beams, propelling us into a realm of discovery like never before.

Source: https://www.nature.com/articles/s41592-024-02224-7