State Key Laboratory of Food Science and Technology, Jiangnan University, School of Food Science and Technology, Jiangnan University , 1800 Lihu Avenue, Wuxi, Jiangsu Province 214122, P. R. China.
J Agric Food Chem. 2017 Jul 19;65(28):5741-5750. doi: 10.1021/acs.jafc.7b02190. Epub 2017 Jul 7.
P34 probable thiol protease (P34) and Gly m Bd 30K (30K) show high relationship with the protease of 24 kDa oleosin of soybean oil bodies. In this study, 9 day germinated soybean was used to separate bioprocessed P34 (P32) from bioprocessed 30K (28K). Interestingly, P32 existed as dimer, whereas 28K existed as monomer; a P32-rich sample had proteolytic activity and high cleavage site specificity (Lys-Thr of 24 kDa oleosin), whereas a 28K-rich sample showed low proteolytic activity; the P32-rich sample contained one thiol protease. After mixing with purified oil bodies, all P32 dimers were dissociated and bound to 24 kDa oleosins to form P32-24 kDa oleosin complexes. By incubation, 24 kDa oleosin was preferentially hydrolyzed, and two hydrolyzed products (HPs; 17 and 7 kDa) were confirmed. After most of 24 kDa oleosin was hydrolyzed, some P32 existed as dimer, and the other as P32-17 kDa HP. It was suggested that P32 was the protease.
P34 可能是硫醇蛋白酶（P34）和 Gly m Bd 30K（30K）与大豆油体 24 kDa 油质体蛋白的蛋白酶具有高度的关系。在本研究中，使用 9 天发芽的大豆从生物加工的 30K（28K）中分离生物加工的 P34（P32）。有趣的是，P32 以二聚体形式存在，而 28K 以单体形式存在；富含 P32 的样品具有蛋白水解活性和高切割位点特异性（24 kDa 油质体蛋白的 Lys-Thr），而富含 28K 的样品显示出低蛋白水解活性；富含 P32 的样品含有一种硫醇蛋白酶。与纯化的油体混合后，所有的 P32 二聚体都解离并与 24 kDa 油质体结合形成 P32-24 kDa 油质体复合物。孵育后，24 kDa 油质体优先水解，并确认了两种水解产物（HP；17 和 7 kDa）。在大部分 24 kDa 油质体被水解后，一些 P32 以二聚体形式存在，另一些以 P32-17 kDa HP 形式存在。这表明 P32 是蛋白酶。
