The energy cost of polypeptide knot formation and its folding consequences

Andrés Bustamante, Juan Sotelo-Campos, Daniel G. Guerra, Martin Floor, Christian A. M. Wilson, Carlos Bustamante () and Mauricio Báez ()
Additional contact information
Andrés Bustamante: Universidad de Chile
Juan Sotelo-Campos: Universidad Peruana Cayetano Heredia
Daniel G. Guerra: Universidad Peruana Cayetano Heredia, Av. Honorio Delgado 430, San Martin de Porras
Martin Floor: Universidad de Chile
Christian A. M. Wilson: Universidad de Chile
Carlos Bustamante: Universidad Peruana Cayetano Heredia, Av. Honorio Delgado 430, San Martin de Porras
Mauricio Báez: Universidad de Chile

Nature Communications, 2017, vol. 8, issue 1, 1-8

Abstract: Abstract Knots are natural topologies of chains. Yet, little is known about spontaneous knot formation in a polypeptide chain—an event that can potentially impair its folding—and about the effect of a knot on the stability and folding kinetics of a protein. Here we used optical tweezers to show that the free energy cost to form a trefoil knot in the denatured state of a polypeptide chain of 120 residues is 5.8 ± 1 kcal mol−1. Monte Carlo dynamics of random chains predict this value, indicating that the free energy cost of knot formation is of entropic origin. This cost is predicted to remain above 3 kcal mol−1 for denatured proteins as large as 900 residues. Therefore, we conclude that naturally knotted proteins cannot attain their knot randomly in the unfolded state but must pay the cost of knotting through contacts along their folding landscape.

Date: 2017
References: Add references at CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.nature.com/articles/s41467-017-01691-1 Abstract (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:natcom:v:8:y:2017:i:1:d:10.1038_s41467-017-01691-1

Ordering information: This journal article can be ordered from
https://www.nature.com/ncomms/

DOI: 10.1038/s41467-017-01691-1

Access Statistics for this article

Nature Communications is currently edited by Nathalie Le Bot, Enda Bergin and Fiona Gillespie

More articles in Nature Communications from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().