In vitro Refolding of PEGylated Lipase

Abstract

Covalent modification of a protein with polyethylene glycol (PEG) has become one of the most widely used and well established drug enhancement strategies in the biopham aceutical industry. The general benefits enjoyed by PEGylation, such as prolonged se rum half lives or reduced immunogenicity in vivo, are well known. By now the PEGylat ion process has been performed with purified proteins, and it is required to recover the desired PEGylation by a multi-step purification process. The ultimate aim of our reserch is to develop an integrated process of PEGylation and in vitro refolding sta rting with inclusion body material. For this, we investgated the feasibility that a protein could be PEGylation under a denaturing condition and also the PEGylated prot eins could be refolded correctly. Using lipase as a model protein, we found that it was PEGylation in the presence of 8 M urea and that the PEG molecules covalently att ached to lipase did not appear to hinder its refolding.

Key Words : PEGylation lipase, PEGylation, refolding, integrated process