, USA, 14.6.2006

A team of researchers from ETH-Zürich have launched a spin-off company, XpresSys, to commercialise novel protein expression technology The development, which improves on existing methods, has the potential to revolutionise screening process for new drugs. The company won second prize last week in Switzerland s Venture 2006 awards in Zurich, and will be seeking investment from foundations and business angels to support commercialisation. XpresSys claims it is the first in the world to succeed in making protein complexes, as opposed to single proteins.  The technique builds on the established method of using a baculovirus vector to introduce foreign DNA into cell cultures. This process was first demonstrated for foreign protein expression in 1983 and, since then, has been a popular tool for the expression of single proteins. The new XpresSys technology builds on the same principal. A DNA strand, which codes for a desired protein, is spliced into a  bacmid , a ring of DNA containing the viral genome within a bacterial cell. The bacmid then infects insect cells as a virus, prompting the production of the desired foreign protein. Improving on this existing technology, XpresSys has devised what it claims is an economic and efficient method to splice multiple strands of DNA, coding for different proteins, into the same vector so that they are expressed together and form into a  protein machine .  Proteins work as integrated multisubunit complexes,  Corinne John, of the XpresSys research team. explained.  Up until now scientists have only looked at parts of protein complexes.  John compared this limitation to trying to understand a problem in a clockwork mechanism by only looking at one cog wheel.  We can now look at all of the proteins that work together, which is analogous to looking at the whole clockwork machine as a system,  she said. The company has completed the research and development phase of this project and is now ready to launch the product commercially. The technology could be applied to improve drug screening methods as it will allow for the testing of protein complexes as novel drug targets.