肌浆和肌原纤维结合钙蛋白酶在猪肉最长肌贮存过程中的变化：对蛋白质降解的新认识。
Sarcoplasmic and myofibril-bound calpains during storage of pork longissimus muscle: New insights on protein degradation.
机构信息
Department of Food and Nutrition, University of Helsinki, 00014 Helsinki, Finland.
Department of Food and Nutrition, University of Helsinki, 00014 Helsinki, Finland.
出版信息
Food Chem. 2022 Mar 15;372:131347. doi: 10.1016/j.foodchem.2021.131347. Epub 2021 Oct 7.
The subcellular distribution of calpain-1 and -2 and the proteolytical activity of myofibril-bound calpains in pork were investigated during 12 days cold storage. The content of sarcoplasmic calpain-1 decreased during storage while myofibril-bound calpain-1 content first increased (P < 0.05) to 17% of that of 12 h-sarcoplasmic calpain-1 on day 6 followed by a gradual decrease with subsequent storage, suggesting that calpain-1 gradually translocated from sarcoplasm to myofibrils during the initial 6 days of postmortem storage. Intact desmin decreased (P < 0.05) after incubation of myofibrils with 0.05 mM Ca, and this was more pronounced with 5 mM Ca (P < 0.05). Ca titration curves of day 6 myofibrils showed two distinct proteolytic activities becoming activated in the range 0.03 to 0.06 mM and 0.4 to 0.8 mM Ca, respectively. The results suggest that both calpain-1 and calpain-2 binds to myofibrils during storage and subsequently degrade structural proteins including desmin.
在 12 天的冷藏过程中，研究了钙蛋白酶-1 和 -2 的亚细胞分布以及肌原纤维结合钙蛋白酶在猪肉中的蛋白水解活性。贮藏过程中肌浆钙蛋白酶-1 的含量逐渐下降，而肌原纤维结合钙蛋白酶-1 的含量先增加（P<0.05），在第 6 天达到 12 小时肌浆钙蛋白酶-1 的 17%，随后随着贮藏时间的延长逐渐减少，表明钙蛋白酶-1 在死后贮藏最初 6 天内逐渐从肌浆向肌原纤维转移。用 0.05 mM Ca 孵育肌原纤维后，完整的结蛋白减少（P<0.05），用 5 mM Ca 时更为明显（P<0.05）。第 6 天肌原纤维的钙滴定曲线显示，两种不同的蛋白水解活性分别在 0.03 至 0.06 mM 和 0.4 至 0.8 mM Ca 范围内被激活。结果表明，钙蛋白酶-1 和钙蛋白酶-2 在贮藏过程中都与肌原纤维结合，随后降解包括结蛋白在内的结构蛋白。
Zotero 插件