AVS 47th International Symposium
    Biomaterial Interfaces Monday Sessions
       Session BI+SS-MoM

Invited Paper BI+SS-MoM7
Formation of 2D Crystals of Proteins on Solid Supports, and Their Application for Immobilizing Molecules or Particles

Monday, October 2, 2000, 10:20 am, Room 202

Session: Biological Surface Science
Presenter: A.D.R. Brisson, University of Groningen, The Netherlands
Correspondent: Click to Email

The immobilization of molecules or particles on solid supports constitutes a central issue in various fields, eg. the immobilization of enzymes in the biosensor area, or the immobilization of DNA molecules on microarrays in genomics. Existing technologies rely mainly on the chemical modification of solid surfaces and the subsequent immobilization of the molecules of interest via non-specific interactions. The strategy we have selected is based on the use of functionalized 2D crystals of proteins formed on solid-supported lipid bilayers (SPBs) as a matrix for anchoring proteins/particles in a specific manner. Its main potential advantages are the wide panoply of functional groups that could be introduced in proteins, the well-known chemistry of the coupling reactions involved, the well-defined density of anchoring groups, and the specificity of the coupling reactions ensuring an oriented binding of bound molecules. In addition, protein 2D crystals could serve as templates for creating ordered arrays of immobilized particles, at the nanometer scale. The formation of SPBs by fusion of lipid vesicles on mica,@footnote 1@ and the growth of protein 2D crystals on SPBs were extensively studied by AFM and Electron Microscopy (EM) in the case of two protein systems, annexin V@footnote 2@ and streptavidin. Pre-formed 2D arrays of modified annexin molecules were used for immobilizing proteins, liposomes, and membrane fragments containing membrane proteins. An unexpected result was the induced ordering of membrane proteins resulting from their specific binding to an ordered protein matrix. On the other hand, while close-packed assemblies of liposomes could be bound to protein 2D arrays, attempts to fuse them into suspended lipid bilayers have yet been unsuccessful. The immobilization of inorganic particles is under investigation. Results of these studies will be presented. @FootnoteText@@footnote 1@Reviakine et al. Langmuir 16, 2000, 1806. @footnote 2@Reviakine et al. J. Struct. Biol. 121, 1998, 356.