English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We study the solvation free energy of two different conformations (helix andextended) of two different peptides (deca-alanine and deca-glycine) in twodifferent solvents (water and aqueous guanidinium chloride, GdmCl). The freeenergies are obtained using the quasichemical organization of the potentialdistribution theorem, an approach that naturally provides the repulsive(solvophobic or cavity) and attractive (solvophilic) contributions tosolvation. The solvophilic contribution is further parsed into a chemistrycontribution arising from solute interaction with the solvent in the firstsolvation shell and a long-range contribution arising from non-specificinteractions between the solute and the solvent beyond the first solvationshell. The cavity contribution is obtained for two different envelopes,$\Sigma_{SE}$ which theory identifies as the solvent excluded volume and alarger envelope ($\Sigma_G$) beyond which solute-solvent interactions areGaussian. For both envelopes, the cavity contribution in water is proportionalto the surface area of the envelope. The same does not hold for GdmCl(aq),revealing limitations of using molecular area to assess solvation energetics,especially in mixed solvents. The $\Sigma_G$-cavity contribution predicts thatGdmCl(aq) should favor the more compact state, contrary to the role of GdmCl inunfolding proteins. The chemistry contribution attenuates this effect, butstill the net local (chemistry plus $\Sigma_G$-packing) contribution isinadequate in capturing the role of GdmCl. With the inclusion of the long-rangecontribution, which is dominated by van~der~Waals interaction, aqueous GdmClfavors the extended conformation over the compact conformation. Our findingemphasizes the importance of weak, but attractive, long-range dispersioninteractions in protein solution thermodynamics.

Solvophobic and solvophilic contributions in the water-to-aqueous guanidinium chloride transfer free energy of model peptides