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Updated: Sep 4, 2025

Investigating Protein Sequence-structure-dynamics Relationships with Bio3D-web
Published on: July 16, 2017
Analysis of β-strand Twist from the 3-dimensional Image of a Protein
Tunazzina Islam1, Michael Poteat1, Jing He1
1Department of Computer Science, Old Dominion University, Norfolk, VA 23529.
Abstract:
Electron cryo-microscopy (Cryo-EM) technique produces density maps that are 3-dimensional (3D) images of molecules. It is challenging to derive atomic structures of proteins from 3D images of medium resolutions. Twist of a β-strand has been studied extensively while little of the known information has been directly obtained from the 3D image of a β-sheet. We describe a method to characterize the twist of β-strands from the 3D image of a protein. An analysis of 11 β-sheet images shows that the Averaged Minimum Twist (AMT) angle is larger for a close set than for a far set of β-traces.
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