Using the MWC model to describe heterotropic interactions in hemoglobin.

Hemoglobin is a classical model allosteric protein. Research on hemoglobin parallels the development of key cooperativity and allostery concepts, such as the 'all-or-none' Hill formalism, the stepwise Adair binding formulation and the concerted Monod-Wymann-Changuex (MWC) allosteric model....

Full description

Saved in:
Bibliographic Details
Main Authors: Olga Rapp, Ofer Yifrach
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2017-01-01
Series:PLoS ONE
Online Access:https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0182871&type=printable
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850076619049271296
author Olga Rapp
Ofer Yifrach
author_facet Olga Rapp
Ofer Yifrach
author_sort Olga Rapp
collection DOAJ
description Hemoglobin is a classical model allosteric protein. Research on hemoglobin parallels the development of key cooperativity and allostery concepts, such as the 'all-or-none' Hill formalism, the stepwise Adair binding formulation and the concerted Monod-Wymann-Changuex (MWC) allosteric model. While it is clear that the MWC model adequately describes the cooperative binding of oxygen to hemoglobin, rationalizing the effects of H+, CO2 or organophosphate ligands on hemoglobin-oxygen saturation using the same model remains controversial. According to the MWC model, allosteric ligands exert their effect on protein function by modulating the quaternary conformational transition of the protein. However, data fitting analysis of hemoglobin oxygen saturation curves in the presence or absence of inhibitory ligands persistently revealed effects on both relative oxygen affinity (c) and conformational changes (L), elementary MWC parameters. The recent realization that data fitting analysis using the traditional MWC model equation may not provide reliable estimates for L and c thus calls for a re-examination of previous data using alternative fitting strategies. In the current manuscript, we present two simple strategies for obtaining reliable estimates for MWC mechanistic parameters of hemoglobin steady-state saturation curves in cases of both evolutionary and physiological variations. Our results suggest that the simple MWC model provides a reasonable description that can also account for heterotropic interactions in hemoglobin. The results, moreover, offer a general roadmap for successful data fitting analysis using the MWC model.
format Article
id doaj-art-12bc4f7ebb7749be89fb65b8be3e7433
institution DOAJ
issn 1932-6203
language English
publishDate 2017-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj-art-12bc4f7ebb7749be89fb65b8be3e74332025-08-20T02:46:00ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-01128e018287110.1371/journal.pone.0182871Using the MWC model to describe heterotropic interactions in hemoglobin.Olga RappOfer YifrachHemoglobin is a classical model allosteric protein. Research on hemoglobin parallels the development of key cooperativity and allostery concepts, such as the 'all-or-none' Hill formalism, the stepwise Adair binding formulation and the concerted Monod-Wymann-Changuex (MWC) allosteric model. While it is clear that the MWC model adequately describes the cooperative binding of oxygen to hemoglobin, rationalizing the effects of H+, CO2 or organophosphate ligands on hemoglobin-oxygen saturation using the same model remains controversial. According to the MWC model, allosteric ligands exert their effect on protein function by modulating the quaternary conformational transition of the protein. However, data fitting analysis of hemoglobin oxygen saturation curves in the presence or absence of inhibitory ligands persistently revealed effects on both relative oxygen affinity (c) and conformational changes (L), elementary MWC parameters. The recent realization that data fitting analysis using the traditional MWC model equation may not provide reliable estimates for L and c thus calls for a re-examination of previous data using alternative fitting strategies. In the current manuscript, we present two simple strategies for obtaining reliable estimates for MWC mechanistic parameters of hemoglobin steady-state saturation curves in cases of both evolutionary and physiological variations. Our results suggest that the simple MWC model provides a reasonable description that can also account for heterotropic interactions in hemoglobin. The results, moreover, offer a general roadmap for successful data fitting analysis using the MWC model.https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0182871&type=printable
spellingShingle Olga Rapp
Ofer Yifrach
Using the MWC model to describe heterotropic interactions in hemoglobin.
PLoS ONE
title Using the MWC model to describe heterotropic interactions in hemoglobin.
title_full Using the MWC model to describe heterotropic interactions in hemoglobin.
title_fullStr Using the MWC model to describe heterotropic interactions in hemoglobin.
title_full_unstemmed Using the MWC model to describe heterotropic interactions in hemoglobin.
title_short Using the MWC model to describe heterotropic interactions in hemoglobin.
title_sort using the mwc model to describe heterotropic interactions in hemoglobin
url https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0182871&type=printable
work_keys_str_mv AT olgarapp usingthemwcmodeltodescribeheterotropicinteractionsinhemoglobin
AT oferyifrach usingthemwcmodeltodescribeheterotropicinteractionsinhemoglobin