SDS/PAGE of purified hQR2. The cloned, overexpressed, and purified hQR2 migrated with a Mr 24.6 kDa. There is a trace contaminant of higher molecular weight. The standards are: RNase (13.7 kDa), soybean trypsin inhibitor (20.1 kDa), carbonic anhydrase (29 kDa), ovalbumin (44 kDa), and BSA (66 kDa).