Key Laboratory of Meat Processing and Quality Control, Ministry of Education China, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
J Agric Food Chem. 2011 Sep 14;59(17):9658-63. doi: 10.1021/jf202129r. Epub 2011 Aug 16.
The objective of the study was to investigate in vitro degradation of myofibrils by caspase-3 or -6. Myofibrillar proteins prepared from beef skeletal muscle were incubated with caspase-3 or -6 at 30 °C for 2 or 12 h, and subsequently, protein degradation was detected. Results showed that caspase-3 and -6 reproduced the degradation patterns of titin and nebulin observed during normal postmortem (PM) aging; however, they only reproduced the 28 kDa fragment derived from troponin-T. Caspase-3 induced only minor degradation of desmin. However, caspase-6 caused increasing degradation of desmin with extended incubation time and produced three degradation fragments (45, 29, and 27 kDa) of which only the 45 kDa fragment has been reported in aged beef. Therefore, caspase-3 or -6 could only reproduce a part of myofibrillar protein degradation or degradation fragments observed in naturally aged meat and may be involved in PM proteolysis of muscle proteins together with other endogenous proteases.
本研究旨在研究 caspase-3 或 -6 对肌原纤维的体外降解作用。从牛骨骼肌中提取肌原纤维蛋白，在 30°C 下用 caspase-3 或 -6 孵育 2 或 12 小时，然后检测蛋白质降解情况。结果表明，caspase-3 和 -6 重现了正常宰后（PM）老化过程中观察到的titin 和 nebulin 的降解模式；然而，它们只重现了来自肌钙蛋白-T 的 28 kDa 片段。caspase-3 仅引起少量的desmin 降解。然而，随着孵育时间的延长，caspase-6 导致 desmin 降解增加，并产生三个降解片段（45、29 和 27 kDa），其中只有 45 kDa 片段在 aged beef 中报道过。因此，caspase-3 或 -6 只能重现自然老化肉中观察到的部分肌原纤维蛋白降解或降解片段，并且可能与其他内源性蛋白酶一起参与 PM 肌肉蛋白的水解。
