FIGURE 8.

Deletion of the CBM or C-terminal region of EndoS affects glycoside hydrolase activity against serum IgG. SDS-PAGE analysis of the reaction components of enzymatic digest of serum IgG with EndoS or EndoS domains as denoted above each lane of the SDS-PAGE gel, where M indicates the molecular weight marker. The left panel shows the SDS-PAGE analysis after a 1-h incubation at 37 °C of IgG with the EndoS domains. The right panel shows the reactions analyzed in an identical manner after 12 h of incubation at 37 °C. The arrows to the right of both panels indicate the position of the upper (glycosylated) and lower (deglycosylated) bands representative of the heavy chain of serum IgG (A). HPLC analysis of residual serum IgG glycan species present after a 1-h incubation with either CBM-KO and ChitLRR. Chromatograms were normalized to the glycan peak at 22 min (B). RF, relative fluorescence units.