LPS MODIFICATION OF MEMBRANES FOR COMPLEX MEMBRANE DESIGN
Kirstie Swingle, Gabriel Montano.
Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM.
Supported lipid bilayers (SLBs) are useful model membrane systems for investigating biological processes and developing sensor technologies. The ability to create complex biological mimics through understanding SLB system boundaries could significantly enhance applications of SLBs. We previously demonstrated the ability to enhance control over SLB organization using lipopolysaccharide (LPS), a component of the outer membrane of Gram-negative bacteria. In a process that is both thermodynamically and kinetically driven, we showed that LPS causes the formation of stable holes in SLBs. In our current work, we extend this approach for membrane modification to create multicomponent assemblies consisting of lipids, polymers, and proteins and demonstrate geometric control of the resultant patterns over hundreds of microns. In addition, we demonstrate a novel memory effect in which LPS is shown to recreate holes at the same locations iteratively, allowing for controlled membrane healing. Lastly, we investigate enhanced stability of SLBs through the addition of small amounts of amphiphilic-block copolymers. Ultimately, our new findings and proposed techniques significantly extend the potential uses and applications of LPS-membrane modification. Our findings advance our ability to generate complex, controlled SLBS for membrane biosensor design and platform development for studying biological interactions.