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Adhesion Properties of Freestanding Hydrophobin Bilayers
Version 2 2018-07-11, 20:03
Version 1 2018-06-29, 21:19
journal contribution
posted on 2018-06-11, 00:00 authored by Hendrik Hähl, Jose Nabor Vargas, Michael Jung, Alessandra Griffo, Päivi Laaksonen, Michael Lienemann, Karin Jacobs, Ralf Seemann, Jean-Baptiste FleuryHydrophobins
are a family of small-sized proteins featuring a distinct
hydrophobic patch on the protein’s surface, rendering them
amphiphilic. This particularity allows hydrophobins to self-assemble
into monolayers at any hydrophilic/hydrophobic interface. Moreover,
stable pure protein bilayers can be created from two interfacial hydrophobin
monolayers by contacting either their hydrophobic or their hydrophilic
sides. In this study, this is achieved via a microfluidic approach,
in which also the bilayers’ adhesion energy can be determined.
This enables us to study the origin of the adhesion of hydrophobic
and hydrophilic core bilayers made from the class II hydrophobins
HFBI and HFBII. Using different fluid media in this setup and introducing
genetically modified variants of the HFBI molecule, the different
force contributions to the adhesion of the bilayer sheets are studied.
It was found that in the hydrophilic contact situation, the adhesive
interaction was higher than that in the hydrophobic contact situation
and could be even enhanced by reducing the contributions of electrostatic
interactions. This effect indicates that the van der Waals interaction
is the dominant contribution that explains the stability of the observed
bilayers.