Dynamic Assembly of Class II Hydrophobins from T. reesei at the Air-Water Interface

Research output: Contribution to journalArticleScientificpeer-review

Researchers

  • Hendrik Hähl
  • Alessandra Griffo
  • Neda Safaridehkohneh
  • Jonas Heppe
  • Sebastian Backes
  • Michael Lienemann
  • Markus Linder

  • Ludger Santen
  • Päivi Laaksonen

  • Karin Jacobs

Research units

  • Saarland University
  • Federal Institute for Materials Research and Testing Berlin
  • VTT Technical Research Centre of Finland

Abstract

Class II hydrophobins are amphiphilic proteins produced by filamentous fungi. One of their typical features is the tendency to accumulate at the interface between an aqueous phase and a hydrophobic phase, such as the air-water interface. The kinetics of the interfacial self-assembly of wild-type hydrophobins HFBI and HFBII and some of their engineered variants at the air-water interface were measured by monitoring the accumulated mass at the interface via nondestructive ellipsometry measurements. The resulting mass vs time curves revealed unusual kinetics for a monolayer formation that did not follow a typical Langmuir-type of behavior but had a rather coverage-independent rate instead. Typically, the full surface coverage was obtained at masses corresponding to a monolayer. The formation of multilayers was not observed. Atomic force microscopy revealed formation and growth of non-fusing protein clusters at the interface. The mechanism of the adsorption was studied by varying the structure or charges of the protein or the ionic strength of the subphase, revealing that the lateral interactions between the hydrophobins play a role in their interfacial assembly. Additionally, a theoretical model was introduced to identify the underlying mechanism of the unconventional adsorption kinetics.

Details

Original languageEnglish
Pages (from-to)9202-9212
Number of pages11
JournalLangmuir
Volume35
Issue number28
Publication statusPublished - 20 Jun 2019
MoE publication typeA1 Journal article-refereed

ID: 35990163