Pegylated Interleukin-22 Mouse Recombinant produced in E.Coli is a single, non-glycosylated homodimeric polypeptide chain containing 147 amino acids and an aditional Ala amino acid at N-terminus having a molecular mass of 36 kDa as determioned by mass spectometry. However due to enlarged hydrodymanic volume it runs on the SDS-PAGE as a 50 kDa protein and in gel-filtration on Superdex 200 as over 200 kDa protein. The Murine IL-22 is Mono-pegylated (with 20 kDa PEG) purified by proprietary chromatographic techniques.