Proteindesign with the human interferon gamma -IFN-Gamma-

Human interferon gamma (IFN gamma) shows pleiotropic effects on its target cells. To proof whether the complete length of this protein is necessary for all these activities, we shortened the NH2- and COOH-terminus by recombinant methods and expressed these variants in E.coli. Up to date 8 amino acids at the NH2-terminus and 11 at the other end can be taken out without a dramatic loss of activity. A variant lacking 10 amino acids at the COOH-end even shows higher antiviral activity than the complete IFN gamma. For structural analysis by x-ray diffraction we crystallized the complete IFN gamma molecule.