title: Reconstitution of the membrane protein OmpF into biomimetic block copolymer-phospholipid hybrid membranes.
abstract: Structure and function of many transmembrane proteins are affected by their environment. In this respect, reconstitution of a membrane protein into a biomimetic polymer membrane can alter its function. To overcome this problem we used membranes formed by poly(1,4-isoprene-block-ethylene oxide) block copolymers blended with 1,2-diphytanoyl-sn-glycero-3-phosphocholine. By reconstituting the outer membrane protein OmpF from Escherichia coli into these membranes, we demonstrate functionality of this protein in biomimetic lipopolymer membranes, independent of the molecular weight of the block copolymers. At low voltages, the channel conductance of OmpF in 1 M KCl was around 2.3 nS. In line with these experiments, integration of OmpF was also revealed by impedance spectroscopy. Our results indicate that blending synthetic polymer membranes with phospholipids allows for the reconstitution of transmembrane proteins under preservation of protein function, independent of the membrane thickness.
authors.affiliation: Institute of Interfacial Process Engineering and Plasma Technology, Department of Chemical Interfacial Process Engineering, University of Stuttgart, Nobelstraße 12, 70569 Stuttgart, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Bieligmeyer
authors.affiliation: Institute of Biomaterials and Biomolecular Systems, Department of Biophysics, University of Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany.
authors.forename: Franjo
authors.initials: F
authors.lastname: Artukovic
authors.affiliation: Institute of Biomaterials and Biomolecular Systems, Department of Biophysics, University of Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Nussberger
authors.affiliation: Institute of Interfacial Process Engineering and Plasma Technology, Department of Chemical Interfacial Process Engineering, University of Stuttgart, Nobelstraße 12, 70569 Stuttgart, Germany; Fraunhofer Institute for Interfacial Engineering and Biotechnology, Department of Interfacial Engineering and Materials Science, Nobelstraße 12, 70569 Stuttgart, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hirth
authors.affiliation: Fraunhofer Institute for Interfacial Engineering and Biotechnology, Department of Interfacial Engineering and Materials Science, Nobelstraße 12, 70569 Stuttgart, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schiestel
authors.affiliation: Fraunhofer Institute for Interfacial Engineering and Biotechnology, Department of Interfacial Engineering and Materials Science, Nobelstraße 12, 70569 Stuttgart, Germany.
authors.forename: Michaela
authors.initials: M
authors.lastname: Müller
keywords: OmpF reconstitution; biomimetics; block copolymer; lipopolymer mixture; self-assembly