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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Inverted solubility--a crystal melting upon cooling--is observed in a handfulof proteins, such as carbomonoxy hemoglobin and $\gamma$D-crystallin. In human$\gamma$D-crystallin, the phenomenon is associated with the mutation of the23$^\mathrm{rd}$ residue, a proline, to a threonine, serine or valine. Oneproposed microscopic mechanism for this effect entails an increase inhydrophobicity upon mutagenesis. Recent crystal structures of a double mutantthat includes the P23T mutation allows for a more careful investigation of thisproposal. Here, we first measure the surface hydrophobicity of various mutantstructures of this protein and determine that it does not discernibly increaseupon the mutating the 23$^\mathrm{rd}$ residue. We then investigate thesolubility inversion regime with a schematic patchy particle model thatincludes one of three models for temperature-dependent patch energies: two ofthe hydrophobic effect, and a more generic description. We conclude that whilesolubility inversion due to the hydrophobic effect may be possible, microscopicevidence to support it in $\gamma$D-crystallin is weak. More generally, we findthat solubility inversion requires a fine balance between patch strengths andthe temperature-dependent contribution, which may explain why invertedsolubility is not commonly observed in proteins. In any event, we also findthat the temperature-dependent interaction has only a negligible impact on thecritical properties of the $\gamma$D-crystallin, in line with previousexperimental observations.

Using schematic models to understand the microscopic basis for inverted solubility in $\gamma$D-crystallin