Contact prediction is hardest for the most informative contacts, but improves with the incorporation of contact potentials.

Co-evolution between pairs of residues in a multiple sequence alignment (MSA) of homologous proteins has long been proposed as an indicator of structural contacts. Recently, several methods, such as direct-coupling analysis (DCA) and MetaPSICOV, have been shown to achieve impressive rates of contact...

Full description

Saved in:
Bibliographic Details
Main Authors: Jack Holland, Qinxin Pan, Gevorg Grigoryan
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2018-01-01
Series:PLoS ONE
Online Access:https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0199585&type=printable
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849766252166250496
author Jack Holland
Qinxin Pan
Gevorg Grigoryan
author_facet Jack Holland
Qinxin Pan
Gevorg Grigoryan
author_sort Jack Holland
collection DOAJ
description Co-evolution between pairs of residues in a multiple sequence alignment (MSA) of homologous proteins has long been proposed as an indicator of structural contacts. Recently, several methods, such as direct-coupling analysis (DCA) and MetaPSICOV, have been shown to achieve impressive rates of contact prediction by taking advantage of considerable sequence data. In this paper, we show that prediction success rates are highly sensitive to the structural definition of a contact, with more permissive definitions (i.e., those classifying more pairs as true contacts) naturally leading to higher positive predictive rates, but at the expense of the amount of structural information contributed by each contact. Thus, the remaining limitations of contact prediction algorithms are most noticeable in conjunction with geometrically restrictive contacts-precisely those that contribute more information in structure prediction. We suggest that to improve prediction rates for such "informative" contacts one could combine co-evolution scores with additional indicators of contact likelihood. Specifically, we find that when a pair of co-varying positions in an MSA is occupied by residue pairs with favorable statistical contact energies, that pair is more likely to represent a true contact. We show that combining a contact potential metric with DCA or MetaPSICOV performs considerably better than DCA or MetaPSICOV alone, respectively. This is true regardless of contact definition, but especially true for stricter and more informative contact definitions. In summary, this work outlines some remaining challenges to be addressed in contact prediction and proposes and validates a promising direction towards improvement.
format Article
id doaj-art-7594e6b273614cfd9e8b7fd27a74d90c
institution DOAJ
issn 1932-6203
language English
publishDate 2018-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj-art-7594e6b273614cfd9e8b7fd27a74d90c2025-08-20T03:04:38ZengPublic Library of Science (PLoS)PLoS ONE1932-62032018-01-01136e019958510.1371/journal.pone.0199585Contact prediction is hardest for the most informative contacts, but improves with the incorporation of contact potentials.Jack HollandQinxin PanGevorg GrigoryanCo-evolution between pairs of residues in a multiple sequence alignment (MSA) of homologous proteins has long been proposed as an indicator of structural contacts. Recently, several methods, such as direct-coupling analysis (DCA) and MetaPSICOV, have been shown to achieve impressive rates of contact prediction by taking advantage of considerable sequence data. In this paper, we show that prediction success rates are highly sensitive to the structural definition of a contact, with more permissive definitions (i.e., those classifying more pairs as true contacts) naturally leading to higher positive predictive rates, but at the expense of the amount of structural information contributed by each contact. Thus, the remaining limitations of contact prediction algorithms are most noticeable in conjunction with geometrically restrictive contacts-precisely those that contribute more information in structure prediction. We suggest that to improve prediction rates for such "informative" contacts one could combine co-evolution scores with additional indicators of contact likelihood. Specifically, we find that when a pair of co-varying positions in an MSA is occupied by residue pairs with favorable statistical contact energies, that pair is more likely to represent a true contact. We show that combining a contact potential metric with DCA or MetaPSICOV performs considerably better than DCA or MetaPSICOV alone, respectively. This is true regardless of contact definition, but especially true for stricter and more informative contact definitions. In summary, this work outlines some remaining challenges to be addressed in contact prediction and proposes and validates a promising direction towards improvement.https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0199585&type=printable
spellingShingle Jack Holland
Qinxin Pan
Gevorg Grigoryan
Contact prediction is hardest for the most informative contacts, but improves with the incorporation of contact potentials.
PLoS ONE
title Contact prediction is hardest for the most informative contacts, but improves with the incorporation of contact potentials.
title_full Contact prediction is hardest for the most informative contacts, but improves with the incorporation of contact potentials.
title_fullStr Contact prediction is hardest for the most informative contacts, but improves with the incorporation of contact potentials.
title_full_unstemmed Contact prediction is hardest for the most informative contacts, but improves with the incorporation of contact potentials.
title_short Contact prediction is hardest for the most informative contacts, but improves with the incorporation of contact potentials.
title_sort contact prediction is hardest for the most informative contacts but improves with the incorporation of contact potentials
url https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0199585&type=printable
work_keys_str_mv AT jackholland contactpredictionishardestforthemostinformativecontactsbutimproveswiththeincorporationofcontactpotentials
AT qinxinpan contactpredictionishardestforthemostinformativecontactsbutimproveswiththeincorporationofcontactpotentials
AT gevorggrigoryan contactpredictionishardestforthemostinformativecontactsbutimproveswiththeincorporationofcontactpotentials