Figure 1: PEGylation reaction of the purified A. flavipes GHTHase (A). GHTHase was conjugated to Methoxy Polyethyleneglycol Propionic acid N-succinimidyl ester (PEG) 5kDa in potassium phosphate buffer (100 mM, pH 7.8). The conjugation was conducted via peptide bond of enzyme surface lysine groups and carboxylic groups of PEG moieties. (B) Fluorescamine assay for reaction with surface lysine amino groups, the emitted fluorescence due to the fluorophor of enzyme-conjugated dye was measured at 450 nm.