AVS 46th International Symposium
    Biomaterial Interfaces Group Monday Sessions
       Session BI-MoM

Paper BI-MoM11
Characterization of S-layer-supported Bilayer Lipid Membranes

Monday, October 25, 1999, 11:40 am, Room 613/614

Session: Biosensor-Biology Interface
Presenter: B. Schuster, Universität für Bodenkultur Wien, Austria
Authors: B. Schuster, Universität für Bodenkultur Wien, Austria
D. Pum, Universität für Bodenkultur Wien, Austria
U.B. Sleytr, Universität für Bodenkultur Wien, Austria
Correspondent: Click to Email
Biosensors, based on electrical detection of specific ligand binding become of increasing importance over the last years. Reliable application make great demands on these designed systems like stable membranes with sufficient fluidity and controlled, orientated linkage of sensing molecules to benefit from the various biological interactions. One promising strategy is the application of bacterial-cell-surface-layers (S-layers) as biocompatible and supporting structures for bilayer lipid membranes (BLM's). S-layer are the simplest self-assembly systems that produce crystalline, mono-molecular, isoporous protein lattices with well-defined topographical and physico-chemical properties. Recent studies on S-layer-supported BLM's demonstrated, that the fluidity of the BLM is retained and an enhanced stability is observed as these BLM's reveal a decreased tendency to rupture in the presence of ionophores or pore-forming proteins. Furthermore, S-layer proteins can be recrystallized on solid supports like gold or silicon wafers, and provide a biocompatible, water-containing layer. Attached BLM's exhibit an increased fluidity compared to dextran- or silane-supported BLM's and the stability is significantly enhanced. Thus, S-layer can be used as an alternative to soft polymer cushions and to common tethers to support functional BLM's. Additionally, a second S-layer can be recrystallized on the opposite face of the membrane. This will allow to employ the intrinsic molecular sieving properties and to immobilize a range of biologically functional molecules in a well-defined position and orientation on the S-layer lattice. Thus, BLM's with attached S-layer(s) in combination with new sensor technology might play an important role in the development of biosensors.