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Khavnekar, S.

Publications and source records attributed to Khavnekar, S..

3 recordsLinked to original sources

Deep reconstructing generative networks for visualizing dynamic biomolecules inside cells

Advances in cryo-electron tomography (cryo-ET) have produced new opportunities to visualize the structures of dynamic macromolecular machinery in native cellular environments. Here, we describe a machine learning approach that can reconstruct the structural landscape and dynamics of biomolecular complexes present in cryo-ET subtomograms. This method, cryoDRGN-ET, learns a deep generative model of 3D density maps directly from subtomogram tilt series images and can capture states diverse in both composition and conformation. We use this approach to reconstruct the in situ translation dynamics of prokaryotic ribosomes, and we reveal the distribution of functional states during translation elongation populated by S. cerevisiae ribosomes inside cells.

biophysics↗

Optimizing Cryo-FIB Lamellas for sub-5 Angstrom in situ Structural Biology

We here present a method based on metallic platinum sputtering that can substantially enhance the quality of subtomogram averages from lamellas and thereby reduce the number of particles needed for high-resolution subtomogram averaging. We provide evidence for the physical background of this improvement and demonstrate its usefulness by producing sub-5[A] ribosome averages from yeast.

molecular biology↗

Multishot Tomography for High-Resolution In Situ Subtomogram Averaging.

Cryo-electron tomography (cryo-ET) and subtomogram averaging (STA) can resolve protein complexes at near atomic resolution, and when combined with focused ion beam (FIB) milling, macromolecules can be observed within their native context. Unlike single particle acquisition (SPA), cryo-ET can be slow, which may reduce overall project throughput. We here propose a fast, multi-position tomographic acquisition scheme based on beam-tilt corrected beam-shift imaging along the tilt axis, which yields sub-nanometer in situ STA averages.

molecular biology↗