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Observation of pH-Induced Protein Reorientation at the Water Surface.

ABSTRACT: Hydrophobins are surface-active proteins that form a hydrophobic, water-repelling film around aerial fungal structures. They have a compact, particle-like structure, in which hydrophilic and hydrophobic regions are spatially separated. This surface property renders them amphiphilic and is reminiscent of synthetic Janus particles. Here we report surface-specific chiral and nonchiral vibrational sum-frequency generation spectroscopy (VSFG) measurements of hydrophobins adsorbed to their natural place of action, the air-water interface. We observe that hydrophobin molecules undergo a reversible change in orientation (tilt) at the interface when the pH is varied. We explain this local orientation toggle from the modification of the interprotein interactions and the interaction of hydrophobin with the water solvent, following the pH-induced change of the charge state of particular amino acids.

SUBMITTER: Meister K

PROVIDER: S-EPMC5451149 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Observation of pH-Induced Protein Reorientation at the Water Surface.

Meister Konrad K Roeters Steven J SJ Paananen Arja A Woutersen Sander S Versluis Jan J Szilvay Géza R GR Bakker Huib J HJ

The journal of physical chemistry letters 20170406 8

Hydrophobins are surface-active proteins that form a hydrophobic, water-repelling film around aerial fungal structures. They have a compact, particle-like structure, in which hydrophilic and hydrophobic regions are spatially separated. This surface property renders them amphiphilic and is reminiscent of synthetic Janus particles. Here we report surface-specific chiral and nonchiral vibrational sum-frequency generation spectroscopy (VSFG) measurements of hydrophobins adsorbed to their natural pla ...[more]

PMID: 28345915

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