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Title: An exhaustive survey of regular peptide conformations using a new metric for backbone handedness ( h )

Abstract

The Ramachandran plot is important to structural biology as it describes a peptide backbone in the context of its dominant degrees of freedom—the backbone dihedral anglesφandψ(Ramachandran, Ramakrishnan & Sasisekharan, 1963). Since its introduction, the Ramachandran plot has been a crucial tool to characterize protein backbone features. However, the conformation or twist of a backbone as a function ofφandψhas not been completely described for bothcisandtransbackbones. Additionally, little intuitive understanding is available about a peptide’s conformation simply from knowing theφandψvalues of a peptide (e.g., is the regular peptide defined byφ = ψ =  - 100°  left-handed or right-handed?). This report provides a new metric for backbone handedness (h) based on interpreting a peptide backbone as a helix with axial displacementdand angular displacementθ, both of which are derived from a peptide backbone’s internal coordinates, especially dihedral anglesφ,ψandω. In particular,hequals sin(θ)d/d|, with range [-1, 1] and negative (or positive) values indicating left(or right)-handedness. The metrichis used to characterize the handedness of every region of the Ramachandran plot for bothcis(ω = 0°) and trans (ω = 180°) backbones, which provides the first exhaustive survey of twist handedness in Ramachandran (φ,ψ) space. These maps fill in the ‘dead space’ within the Ramachandran plot, which are regions that are not commonly accessed by structured proteins, butmore » which may be accessible to intrinsically disordered proteins, short peptide fragments, and protein mimics such as peptoids. Finally, building on the work of (Zacharias & Knapp, 2013), this report presents a new plot based ondandθthat serves as a universal and intuitive alternative to the Ramachandran plot. The universality arises from the fact that the co-inhabitants of such a plot include every possible peptide backbone includingcisandtransbackbones. The intuitiveness arises from the fact thatdandθprovide, at a glance, numerous aspects of the backbone including compactness, handedness, and planarity.« less

Authors:
 [1]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Molecular Foundry ; Multiscale Inst., Redwood, CA (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1379850
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
PeerJ
Additional Journal Information:
Journal Volume: 5; Journal ID: ISSN 2167-8359
Publisher:
PeerJ Inc.
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; ramachandran plot; peptide backbone; backbone chirality; backbone handedness; miyazawa; peptide helix; protein structure

Citation Formats

Mannige, Ranjan V. An exhaustive survey of regular peptide conformations using a new metric for backbone handedness ( h ). United States: N. p., 2017. Web. doi:10.7717/peerj.3327.
Mannige, Ranjan V. An exhaustive survey of regular peptide conformations using a new metric for backbone handedness ( h ). United States. doi:10.7717/peerj.3327.
Mannige, Ranjan V. Tue . "An exhaustive survey of regular peptide conformations using a new metric for backbone handedness ( h )". United States. doi:10.7717/peerj.3327. https://www.osti.gov/servlets/purl/1379850.
@article{osti_1379850,
title = {An exhaustive survey of regular peptide conformations using a new metric for backbone handedness ( h )},
author = {Mannige, Ranjan V.},
abstractNote = {The Ramachandran plot is important to structural biology as it describes a peptide backbone in the context of its dominant degrees of freedom—the backbone dihedral anglesφandψ(Ramachandran, Ramakrishnan & Sasisekharan, 1963). Since its introduction, the Ramachandran plot has been a crucial tool to characterize protein backbone features. However, the conformation or twist of a backbone as a function ofφandψhas not been completely described for bothcisandtransbackbones. Additionally, little intuitive understanding is available about a peptide’s conformation simply from knowing theφandψvalues of a peptide (e.g., is the regular peptide defined byφ = ψ =  - 100°  left-handed or right-handed?). This report provides a new metric for backbone handedness (h) based on interpreting a peptide backbone as a helix with axial displacementdand angular displacementθ, both of which are derived from a peptide backbone’s internal coordinates, especially dihedral anglesφ,ψandω. In particular,hequals sin(θ)d/d|, with range [-1, 1] and negative (or positive) values indicating left(or right)-handedness. The metrichis used to characterize the handedness of every region of the Ramachandran plot for bothcis(ω = 0°) and trans (ω = 180°) backbones, which provides the first exhaustive survey of twist handedness in Ramachandran (φ,ψ) space. These maps fill in the ‘dead space’ within the Ramachandran plot, which are regions that are not commonly accessed by structured proteins, but which may be accessible to intrinsically disordered proteins, short peptide fragments, and protein mimics such as peptoids. Finally, building on the work of (Zacharias & Knapp, 2013), this report presents a new plot based ondandθthat serves as a universal and intuitive alternative to the Ramachandran plot. The universality arises from the fact that the co-inhabitants of such a plot include every possible peptide backbone includingcisandtransbackbones. The intuitiveness arises from the fact thatdandθprovide, at a glance, numerous aspects of the backbone including compactness, handedness, and planarity.},
doi = {10.7717/peerj.3327},
journal = {PeerJ},
number = ,
volume = 5,
place = {United States},
year = {Tue May 16 00:00:00 EDT 2017},
month = {Tue May 16 00:00:00 EDT 2017}
}

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