The Nanocell project is a European research project with partners from Germany (TU Dresden, MPI Göttingen, MPI Frankfurt), UK (University of Oxford), and Switzerland (U Basel, U Geneva, ETH Zurich). The overall goal is to engineer molecular machines that allow providing artificial cells with functionalities, such as energy generation, movement, transport of genetic material, and protein production. The subproject at ETH Zurich focuses on cell free protein production. First, we intend to implement an efficient process to produce proteins in a cell-free fashion by using cell-free extracts obtained from the protein Escherichia coli. Such extracts contain, next to the desired components of the protein production machinery, a variety of enzymes that interfere with a long-term protein production process, such as enzymes that remove energy carriers (ATP) from the system. These interfering activities will be comprehensively identified in a systems-level approach and the corresponding genes will be either knocked out or modified such that the corresponding enzyme activities can be removed from the cell free stage by selective protein hydrolysis. In a second step of the project, we will investigate whether we can substitute energy rich chemicals (such as phosphoenolpyruvate), which are usually used to drive cell free protein synthesis, by light. For this, the cell free extracts have to be turned into the intererior of vesicles whose membranes harbor photosynthetic complexes. The complexes can be used to establish proton gradients across a vesicle membrane and then, the proton gradients can be used to generate ATP. Previous attempts at this scheme were frustrated by the limited stability of the photosynthetic complexes. Together with our partners, we hope to be able to eliminate this problem by using recently discovered novel types of light-complexes and artificial membranes. In the final stages of the project (beyond 3 years), we aim to extend the functions of the vesicle by integrating into the artificial membranes additional functionalities provided form partner groups, such as (1) a DNA-transporter, which would be an important contribution to the efficiency of in vivo directed evolution experiments, and (2) a peptide transporter, which would allow providing resources for protein formation from the outside.
1.a) Regulation und Lokalisation der Nitritreduktase unter evolutionaerem Aspekt. Dabei wird die Molekularbiologie zur Identifizierung der pro- bzw. eukaryotischen Isoenzyme hinzugezogen. b) Mit Hilfe von Mutanten wird die Regulation der Nitratreduktase untersucht. Schwergewicht ist die in vitro Produktion vom Molybdaen-haltigen Komplex (MoCo) zur Charakterisierung. c) Proteolytischer Abbau der Nitratreduktasen im Zuge des Enzymturnover und der Senescenz. 2. Sterile Fichtenkeimlinge in Hydrokultur werden mit den Schadgasen SO2, O3 und NO2 in Kombinationen begast. Gemessen werden Veraenderungen von Enzymaktivitaeten im N- und C-Metabolismus. 3. Die Charakteristik des N-Stoffwechsels von Rueben wird untersucht, ihre qualitaetsbestimmenden Faktoren in Hinsicht auf gespeicherten Stickstoff bestimmt. Es kommt auf Aufnahme und Reduktion von Nitrat und den regulierenden Einfluss von Polyaminen an.