(1) Departamento de Bioquímica e Imunologia. ICB-UFMG, Belo Horizonte, Brazil.
(2) Departamento de Microbiologia. ICB-UFMG, Belo Horizonte, Brazil.
(3) Instituto Adolfo Lutz. São Paulo, Brazil.
Interferons(IFNS) are a group structurally and funcionally related proteins,induced by bacteria, viruses, double strand RNAs and known by their ability to develop antiviral, antitumor, cell growth regulatory and immuno-modulatory activites in cells. Crystalization of type I IFN was frist reported in IFN-Alpha recombinant DNA and more recently MuIFN-Beta. The three-dimensional crystal structure of recombinant MuIFN-Beta described consist of a bundle of five alpha-helices folded in a yet known topology. Model building studies show that nor only the structure of HuIFN-Beta but also those of various species of IFN-Alpha can be constructed assuming the same structural framework. Comparison with tertiary structures determined for nine members of helical bundle family of cytokines show that they can be further divided into three apparent groups that was refer by ROZWARSKI et al. (ROZWARSKI, D. A. GRONENBORN, A. M., CLORE, G.M. et al.) The short chain (five structures known), the long-chain (two structures known) and the interferon - like (two structures known) sub-familes. Based on the interferon type I proposal models (2hie and 2hif) , the models hybrids of HuIFN Alpha-Beta and HuIFN Beta-Alpha was built using the homology module with InsightII. Using recombinant DNA methods, the models was expressed in E.coli. The biological activities was modified when hybrids tested in vitro.