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arXiv · 1104.2261

On universal aspects of the left-handed helix region

Martin Lundgren·Antti J. Niemi·Fan Sha
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Abstract

We inspect the geometry of proteins by identifying their backbones as framed polygons. We find that the left-handed helix region of the Ramachandran map for non-glycyl residues corresponds to an isolated and highly localized sector in the orientation of the $C_\beta$ carbons, when viewed in a Frenet frame that is centered at the corresponding $C_\alpha$ carbons. We show that this localization in the orientation persists to $C_\gamma$ and $C_\delta$ carbons. Furthermore, when we extend our analysis to the neighboring residues we conclude that the left-handed helix region reflects a very regular and apparently residue independent collective interplay of at least seven consecutive amino acids.

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Martin Lundgren, Antti J. Niemi, Fan Sha. 2011-04-12. On universal aspects of the left-handed helix region. https://arxiv.org/abs/1104.2261

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