7 research outputs found
Single Hemichannels Recorded in Lipid Bilayers and Artificial Gap Junction Formation with Cells
Functional reconstitution of connexons in artificial membranes: expression, purification and characterization of connexin 43
Permeabilization Assay for Antimicrobial Peptides Based on Pore-Spanning Lipid Membranes on Nanoporous Alumina
Screening tools to study antimicrobial
peptides (AMPs) with the
aim to optimize therapeutic delivery vectors require automated and
parallelized sampling based on chip technology. Here, we present the
development of a chip-based assay that allows for the investigation
of the action of AMPs on planar lipid membranes in a time-resolved
manner by fluorescence readout. Anodic aluminum oxide (AAO) composed
of cylindrical pores with a diameter of 70 nm and a thickness of up
to 10 ÎĽm was used as a support to generate pore-spanning lipid
bilayers from giant unilamellar vesicle spreading, which resulted
in large continuous membrane patches sealing the pores. Because AAO
is optically transparent, fluid single lipid bilayers and the underlying
pore cavities can be readily observed by three-dimensional confocal
laser scanning microscopy (CLSM). To assay the membrane permeabilizing
activity of the AMPs, the translocation of the water-soluble dyes
into the AAO cavities and the fluorescence of the sulforhodamine 101
1,2-dihexadecanoyl-<i>sn</i>-glycero-3-phosphoethanol-l-amine
triethylammonium salt (Texas Red DHPE)-labeled lipid membrane were
observed by CLSM in a time-resolved manner as a function of the AMP
concentration. The effect of two different AMPs, magainin-2 and melittin,
was investigated, showing that the concentrations required for membrane
permeabilization and the kinetics of the dye entrance differ significantly.
Our results are discussed in light of the proposed permeabilization
models of the two AMPs. The presented data demonstrate the potential
of this setup for the development of an on-chip screening platform
for AMPs
Permeabilization Assay for Antimicrobial Peptides Based on Pore-Spanning Lipid Membranes on Nanoporous Alumina
Synthetic biology, inspired by synthetic chemistry
The topic synthetic biology appears still as an 'empty basket to be filled'. However, there is already plenty of claims and visions, as well as convincing research strategies about the theme of synthetic biology. First of all, synthetic biology seems to be about the engineering of biology -about bottom-up and top-down approaches, compromising complexity versus stability of artificial architectures, relevant in biology. Synthetic biology accounts for heterogeneous approaches towards minimal and even artificial life, the engineering of biochemical pathways on the organismic level, the modelling of molecular processes and finally, the combination of synthetic with nature-derived materials and architectural concepts, such as a cellular membrane. Still, synthetic biology is a discipline, which embraces interdisciplinary attempts in order to have a profound, scientific base to enable the re-design of nature and to compose architectures and processes with man-made matter. We like to give an overview about the developments in the field of synthetic biology, regarding polymer-based analogs of cellular membranes and what questions can be answered by applying synthetic polymer science towards the smallest unit in life, namely a cell. (C) 2012 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved