Tabakmosaikviren als Biotemplate für Oxidkeramiken
Final Report Abstract
In the course of the project we have investigated the production of several tobacco mosaic virus (TMV) coat protein (CP) mutants in a range of host plants, yeasts and distinct Escherichia coli strains, with the goal to allocate a variety of differently charged nanorod templates supporting mineralization on their tailored protein surfaces. TMV rods are promising scaffolds for the deposition of oxide ceramics for the precise generation of nano-structured components and devices. The 300 nm long, tubular plant virus is comprised of ~2130 identical CP subunits arranged through self-assembly helically around its RNA genome. We investigated in detail the combination of different CP variants in mixed assembly in vitro experiments and could show that it is possible to fine-tune the surface charge distribution by inserting a subproportion of special CPs into, for example, the context of wildtype particles. The influence of these interspersed deviant CP subunits on mineralization of the nanoparticles is currently being investigated in a follow-up project granted by the DFG. To change the surface charge distribution to a further extent, we introduced different peptides in a surface loop or at the C-terminus of the TMV CP and expressed these mutants either in the context of the whole TMV genome in plants, or alone in E. coli. Propagation in plants resulted in an induction of symptoms ranging from leaf curling over stunting to severe stem necrosis three weeks post inoculation. However, most of the mutants could not be purified as virus-like particles. Therefore expression of wildtype and mutant CPs in yeasts and in E. coli was set up in parallel. Here one yeast systems (Pichia pastoris) had the disadvantage to not express CP at all however expression in Schizosaccharomyces pombe could be improved. Additionally yields in E. coli were high, and the so-produced CPs will be used for in-vitro assembly of virus-like nanotubes composed of mixed CP species as well. Although lacking the N-terminal acetylation, thought to be obligatory for assembly of TMV-like rods, we could show for the first time that it is possible to assemble C-terminally His-tagged CP into mixed particles in vitro, irrespective of whether this mutant was derived from plants or E. coli. These findings open up the possibility to express strongly altered CP mutants in a bacterial host and thus to design novel surface properties of viruslike nanotubes by aid of mixed in vitro reconstitution, to meet our needs for defined oxide ceramics deposition onto TMV. This work resulted in a joint publication with the Institute of materials research which gained the interest of many public media resulting in an ongoing cooperation between the project partners in course of the priority programme 1569.
Publications
- 2011. Virus-templated synthesis of ZnO nanostructures and formation of field-effect transistors. Adv. Mater. 23(42), 4918-4922
Atanasova, P., Rothenstein, D., Schneider, J.J., Hoffmann, R.C., Dilfer, S., Eiben, S., Wege, C., Jeske, H., Bill, J.
- 2013. In vivo self-assembly of TMV-like particles in yeast and bacteria for nanotechnological applications. J. Virol. Methods 189(2), 328-340
Kadri, A., Wege, C., Jeske, H.
(See online at https://doi.org/10.1016/j.jviromet.2013.02.017) - 2013. TMV nanorods with programmed longitudinal domains of differently addressable coat proteins. Nanoscale 5(9), 3808- 3816
Geiger, F.C., Eber, F.J., Eiben, S., Mueller, A., Jeske, H., Spatz, J.P., Wege, C.
(See online at https://doi.org/10.1039/c3nr33724c)
