Overexpression and purification of non-glycosylated recombinant endo-beta-N-acetylglucosaminidase F3.

The gene for endo-beta-N-acetylglucosaminidase F3 was cloned into the high-expression vector pMAL c-2, and expressed in Escherichia coli as a fusion protein. A key step in the purification employed Poros II (HS) chromatography, which greatly facilitated isolation of the enzyme from crude intracellular lysates. The unfused enzyme was recovered following digestion with Factor Xa and was isolated in a homogeneous form. The enzyme is non-glycosylated and fully active, and is a very useful analytical tool for investigating the structure of asparagine-linked glycans, especially those with core-substituted alpha 1,6 fucosyl residues.