Liu Rui, Wu Guo-Yue, Li Ke-Yue, Ge Qing-Feng, Wu Man-Gang, Yu Hai, Wu Sheng-Long, Bao Wen-Bin
Industrial Engineering Center for Huaiyang Cuisine of Jiangsu Province, College of Food Science and Engineering, Yangzhou University, Yangzhou 225127, China.
Jiangsu Key Laboratory of Animal Genetic Breeding and Molecular Design, College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China.
Foods. 2021 Mar 30;10(4):733. doi: 10.3390/foods10040733.
In this paper, the protein changes during aging and the differences in the myofibrillar protein fraction at 1 h postmortem of pale, soft and exudative (PSE), and red, firm and non-exudative (RFN) pork (LT) were comparatively studied. The PSE and RFN groups were screened out based on the differences in their pH and lightness () at 1 h, and their purge loss at 24 h postmortem. Based on the measured MFI, desmin degradation, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, PSE meat presented more significant changes in the myofibrillar protein fraction compared to RFN meat during postmortem aging. Through liquid chromatograph-mass spectrometer/mass spectrometer (LC-MS/MS) analysis, a total of 172 differential proteins were identified, among which 151 were up-regulated and 21 were down-regulated in the PSE group. The differential proteins were muscle contraction, motor proteins, microfilaments, microtubules, glycolysis, glycogen metabolism, energy metabolism, molecular chaperones, transport, and enzyme proteins. The AMP activated protein kinase (AMPK) signaling pathway, HIF-1 signaling pathway, calcium signaling pathway, and PI3K-Akt signaling pathway were identified as the significant pathways related to meat quality. This study suggested that the different changes of the myofibrillar protein fraction were involved in the biochemical metabolism in postmortem muscle, which may contribute to the molecular understanding of PSE meat formation.
本文对衰老过程中的蛋白质变化以及宰后1小时苍白、柔软、渗水（PSE）猪肉和红色、坚实、不渗水（RFN）猪肉（腰大肌）肌原纤维蛋白组分的差异进行了比较研究。根据宰后1小时的pH值和亮度（）以及宰后24小时的滴水损失差异筛选出PSE组和RFN组。基于测得的肌原纤维小片化指数（MFI）、结蛋白降解以及十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）分析，宰后成熟过程中，PSE肉的肌原纤维蛋白组分变化比RFN肉更为显著。通过液相色谱-质谱联用仪/质谱仪（LC-MS/MS）分析，共鉴定出172种差异蛋白，其中PSE组有151种上调，21种下调。差异蛋白包括肌肉收缩蛋白、运动蛋白、微丝、微管、糖酵解、糖原代谢、能量代谢、分子伴侣、转运蛋白和酶蛋白。AMP激活蛋白激酶（AMPK）信号通路、缺氧诱导因子-1（HIF-1）信号通路、钙信号通路和磷脂酰肌醇3-激酶-蛋白激酶B（PI3K-Akt）信号通路被确定为与肉质相关的重要信号通路。本研究表明，肌原纤维蛋白组分的不同变化参与了宰后肌肉的生化代谢，这可能有助于从分子层面理解PSE肉的形成。
