Wang Li, Ding Yuanyuan, Zhang Xinxia, Li Yongfu, Wang Ren, Luo Xiaohu, Li Yanan, Li Juan, Chen Zhengxing
State Key Laboratory of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi 214122, China; School of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Lihu Road 1800, Wuxi 214122, China.
State Key Laboratory of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi 214122, China; School of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, Lihu Road 1800, Wuxi 214122, China.
Food Chem. 2018 Jan 15;239:416-426. doi: 10.1016/j.foodchem.2017.06.090. Epub 2017 Jun 16.
To isolate a novel peptide with specific calcium-binding capacity, wheat germ protein was hydrolyzed. The hydrolysates were purified using ultrafiltration, anion-exchange chromatography, gel filtration chromatography, and reversed-phase high performance liquid chromatography. The amino acid sequence of the purified peptide was determined and confirmed to be FVDVT (Phe-Val-Asp-Val-Thr). The calcium-binding capacity of FVDVT reached 89.94±0.75%, increased by 86.37% compared to the hydrolysates. The chelating mechanism between FVDVT and calcium was further investigated by Ultraviolet-Visible absorption spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and H nuclear magnetic resonances spectroscopy. The results indicated that the oxygen atoms of the carboxy group and the nitrogen atoms of the amido group provided major binding sites. In addition, aspartic acid and threonine show considerable capacity for incorporating with calcium by donating electron pairs. This study provides a feasible approach to isolate calcium-binding peptides and to clarify the possible binding mechanism of calcium and peptide.
为了分离出具有特定钙结合能力的新型肽，对小麦胚芽蛋白进行了水解。水解产物通过超滤、阴离子交换色谱、凝胶过滤色谱和反相高效液相色谱进行纯化。测定了纯化肽的氨基酸序列，确定为FVDVT（苯丙氨酸-缬氨酸-天冬氨酸-缬氨酸-苏氨酸）。FVDVT的钙结合能力达到89.94±0.75%，与水解产物相比提高了86.37%。通过紫外可见吸收光谱、傅里叶变换红外光谱、X射线衍射和氢核磁共振光谱进一步研究了FVDVT与钙之间的螯合机制。结果表明，羧基的氧原子和酰胺基的氮原子提供了主要结合位点。此外，天冬氨酸和苏氨酸通过提供电子对表现出与钙结合的相当能力。本研究为分离钙结合肽和阐明钙与肽可能的结合机制提供了一种可行的方法。
