Lysine-deficient lymphotoxin-α mutant for site-specific PEGylation

► The cytokine lymphotoxin-α (LTα) is a promising anticancer agent. ► PEGylation is the approach to enhance the therapeutic potential of protein. ► Here, we created a lysine-deficient mutant LTα (LT-K0) by phage display. ► N-terminus-specific PEGylation of LT-K0 had higher bioactivity than PEGylated LTα. ► These results suggest that PEGylated LT-K0 may be useful in cancer therapy.