This invention provides crystalline recombinant interferon (rSIFN-co) having (i) the same amino acid sequence as that of human consensus interferon, and (ii) altered three-dimensional structure as compared to IFN-±2b. The interferon of the present invention exhibits enhanced biological activities. The present invention also provides a structural model of said interferon useful for drug screening and/or drug design, and mimetics of said interferon.