Authors: A. Güven, S. Ihle, M. Fioroni, U. Schwaneberg
Affilation: Jacobs University Bremen, School of Engineering and Science, Germany
Pages: 325 - 327
Keywords: synthosomes, nanocompartments, controlled release, bioconversion, selective product recovery
The combination of natural proteins with polymer membranes allows the formation of a novel nanocompartment combining the mechanical, chemical, and biological stability of the amphiphilic block copolymer with the functional specificity of membrane proteins. Functional nanocompartments (Synthosomes) are nanometer sized hollow spheres (50-1000 nm) consisting of a block copolymer membrane and an engineered transmembrane protein (OmpF, Tsx, FhuA). In contrast to Polymersomes, the transmembrane channel proteins control the compound flux in and out polymer vesicles. Selective product recovery and enzymatic conversions have been achieved in Synthosomes. For selective recovery of negatively charged compounds (sulforhodamine B and single stranded DNA), positively charged polylysine molecules were entrapped inside Synthosomes. Conversion in Synthosomes was achieved by 3,3’,5,5’-tetramethylbenzidine oxidation employing horseradish peroxidase. Four channel proteins (OmpF, FhuA, FhuA 1-127 and FhuA 1-160) and PMOXA-PDMS-PMOXA triblock copolymer were preferred for nanocompartment formation. Based on the aforementioned work, a first reduction trigger release has been developed by chemically labeling six lysine amino acids in the interior barrel part of FhuA 1-160 with a disulfide linker. The biotin- and pyridyl-labeled FhuA 1-160 prevented the translocation of calcein molecules out of loaded Synthosomes. Upon reduction of disulfide linkers, a fast release of calcein was recorded.