Isolation and characterisation of sericin antifreeze peptides and molecular dynamics modelling of their ice-binding interaction

卷:174

Wu, Jinhong ; Rong, Yuzhi ; Wang, Zhengwu ; Zhou, Yanfu ; Wang, Shaoyun ; Zhao, Bo

关键词: Sericin peptides;    Antifreeze activity;    Isolation;    Ice-binding;    Molecular dynamic modelling;   

DOI  :  10.1016/j.foodchem.2014.11.100

学科分类：食品科学和技术

【 摘 要 】

This study aimed to isolate and characterise a novel sericin antifreeze peptide and investigate its ice-binding molecular mechanism. The thermal hysteresis activity of ice-binding sericin peptides (I-SP) was measured and their activity reached as high as 0.94 degrees C. A P4 fraction, with high hypothermia protective activity and inhibition activity of ice recrystallisation, was obtained from 1-SP, and a purified sericin peptide, named SM-AFP, with the sequence of TTSPTNVSTT and a molecular weight of 1009.50 Da was then isolated from the P4 fraction. Treatment of Lactobacillus delbrueckii Subsp. bulgaricus LB340 LYO with 100 mu g/ml synthetic SM-AFP led to 1.4-fold increased survival (p < 0.05). Finally, an SM-AFP/ice binding model was constructed and results of molecular dynamics simulation suggested that the binding of SM-AFP with ice and prevention of ice crystal growth could be attributed to hydrogen bond formation, hydrophobic interaction and non-bond interactions. Sericin peptides could be developed into beneficial cryoprotectants and used in frozen food processing. (C) 2014 Elsevier Ltd. All rights reserved.