26 © 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Alois Jungbauer is currently working in the field of bioengineering of proteins, plasmids and viruses, with special focus on (a) expression, (b) downstream processing and (c) characterization of large biomolecules. He has been deeply involved in the development of novel concepts for separation of large biomolecules, namely the monoliths with macropores [1,2]. Characteristic for large biomolecules is the diffusional limitation into porous media [3]. Monolithic media are cast as a single block, interlaced by channels ramified with macropores (Fig. 1), thus the channels are perfused and adsorption is not limited by mass transfer resistancy [4–6]. Development of tailor-made pore structure for separation and catalytic purposes, storage and controlled release lead to monoliths with novel features and novel applications [7–9]. He is also active in the expression of proteins in yeast, E.coli and mammalian cells. In joint research projects he has developed a multi protein expression/purification system for expression of unknown gene products and subsequent purification in a high throughput mode [11–17]. This work was also the basis for ongoing research projects to generate secretory protein/peptide libraries for blocking antibodies, developed during autoimmune disease [18,19]. Expression of proteins in E.coli often leads to formation of inclusion bodies. This phenomenon can be readily exploited to develop efficient bioprocesses [20]. Alois Jungbauer also works on the refolding of proteins in the Austrian Center of Biopharmaceutical Technology (ACBT) and has developed several strategies for continuous refolding of proteins either in solution [21] or in chromatography columns [22–24]. Another research area is the reconstitution of steroid hormone receptors in yeast [25–30]. In this program he could utilize the experience from the multi-protein expression system. Direct application of these activities is screening systems for hormonal active compounds and transactivation of steroid hormone receptors, which is performed in the recently founded Christian Doppler Laboratory of Receptor Biotechnology. Steroid hormone receptors and their accompanying proteins constitute an interesting molecular machine and can be used as model for active transport of a macromolecule through a pore. This is an important problem in nanobiotechnology. Efficient expression and purification of all involved proteins are the fundamental basis for further research in this area.