Abstract
Hydrophobins are surface-active fungal proteins that adsorb to the water-air interface and self-assemble into amphiphilic, water-repelling films that have a surface elasticity that is an order of magnitude higher than other molecular films. Here we use surface-specific sum-frequency generation spectroscopy (VSFG) and site-directed mutagenesis to study the properties of class I hydrophobin (HFBI) films from Trichoderma reesei at the molecular level. We identify protein specific HFBI signals in the frequency region 1200-1700 cm-1 that have not been observed in previous VSFG studies on proteins. We find evidence that the aspartic acid residue (D30) next to the hydrophobic patch is involved in lateral intermolecular protein interactions, while the two aspartic acid residues (D40, D43) opposite to the hydrophobic patch are primarily interacting with the water solvent.
| Original language | English |
|---|---|
| Pages (from-to) | 9398-9402 |
| Journal | The Journal of Physical Chemistry B |
| Volume | 121 |
| Issue number | 40 |
| DOIs | |
| Publication status | Published - 12 Oct 2017 |
| MoE publication type | A1 Journal article-refereed |
Funding
This work is financially supported by the “Nederlandse organisatie voor Wetenschappelijk Onderzoek (NWO)”. K.M. gratefully acknowledges the European Commission for funding through the award of a Marie Curie fellowship. A.P. and M.L. acknowledge support by the Academy of Finland through its Centres of Excellence Programme (2014-2019).
Keywords
- Air
- Aspartic Acid/chemistry
- Elasticity
- Fungal Proteins/chemistry
- Hydrophobic and Hydrophilic Interactions
- Molecular Structure
- Mutagenesis, Site-Directed
- Spectrophotometry/methods
- Surface Properties
- Trichoderma
- Vibration
- Water/chemistry