<p>(A) Purified rhPDGF-BB proteins from six independent expression and purification experiments were analyzed by SDS-PAGE. Heterogeneous rhPDGF-BB bands could be observed under reducing conditions. (B) Purified rhPDGF-BB and rhIFN-ω produced by <i>P</i>. <i>pastoris</i> were treated with PNGase F to hydrolyze N-glycan residues. Two gels loaded with the same amount of each protein (5 μg) were simultaneously subjected to SDS-PAGE, and analyzed by Coomassie Blue staining (left panel) and glycosylation staining (right panel), respectively. There were no differences between rhPDGF-BB samples treated or not with PNGase F.</p
