PURIFICATION AND PARTIAL CHARACTERIZATION OF MOUSE FIBROBLAST INTERFERON INDUCED BY SYNTHESIZED POLYRIBOADENYLIC ACID: POLYRIBO-5-AZIDOURIDYLIC ACID HYBRID

Abstract

Interferon (IFN) induced in Swiss mouse embryo primary tissue culture by synthesized polyriboadenylic acid: polyribo-5-azidouridylic acid was purified by a procedure which involved salt precipitation by zinc acetate, ion-exchange chromatography and SDS-polyacrylamide gel electrophoresis. The final activity obtained was 2.86 x 105 U/mg protein (5.06 x 105 IRU/gm protein). The protein had an estimated molecular weight of 46,238 ± 694 daltons and 45,100 ± 710 daltons under denaturing and non-denaturing conditions respectively. An estimated molecular weight of 52,480 ± 707 daltons was however obtained by gel-filtration on Sephadex G-200. The IFN protected mouse embryo cells against Potiskum viral cytopathic effect and showed appreciable stability to the action of neuraminidase. However, activity was rapidly destroyed by trypsin and ultraviolet light. Analysis of sugar indicated that the IFN is a glycoprotein. It also contained one polypeptide chain.