Repository logo
 

The Effect of Pulling and Twisting Forces on Chameleon Sequence Peptides.

Published version
Peer-reviewed

Repository DOI


Change log

Authors

Meadows, James 

Abstract

Chameleon sequences are amino acid sequences found in several distinct configurations in experiment. They challenge our understanding of the link between sequence and structure, and provide insight into structural competition in proteins. Here, we study the energy landscapes for three such sequences, and interrogate how pulling and twisting forces impact the available structural ensembles. Chameleon sequences do not necessarily exhibit multiple structural ensembles on a multifunnel energy landscape when we consider them in isolation. The application of even small forces leads to drastic changes in the energy landscapes. For pulling forces, we observe transitions from helical to extended structures in a very small span of forces. For twisting forces, the picture is much more complex, and highly dependent on the magnitude and handedness of the applied force as well as the reference angle for the twist. Depending on these parameters, more complex and more simplistic energy landscapes are observed alongside more and less diverse structural ensembles. The impact of even small forces is significant, confirming their likely role in folding events. In addition, small forces exerted by the remaining scaffold of a protein may be sufficient to lead to the adoption of a specific structural ensemble by a chameleon sequence.

Description

Publication status: Published


Funder: Cambridge Philosophical Society; doi: http://dx.doi.org/10.13039/100013858

Keywords

chameleon sequences, energy landscapes, mechanical forces, structural ensembles, Protein Structure, Secondary, Peptides, Proteins, Amino Acid Sequence

Journal Title

Chemphyschem

Conference Name

Journal ISSN

1439-4235
1439-7641

Volume Title

Publisher

Wiley