电刺激改善牛肉嫩度的蛋白质组学研究

[目的]研究电刺激处理对宰后成熟过程中牛肉蛋白质的影响。[方法]利用牛背最长肌双向电泳凝胶体系研究电刺激后牛背最长肌中的差异蛋白质,分析宰后1和3 d时电刺激处理牛背最长肌中有显著降解的差异蛋白点。[结果]与未电刺激样品相比,在宰后1和3 d电刺激处理牛背最长肌中有12个蛋白点表达明显下调,分为9种蛋白质:肌间线蛋白、肌钙蛋白-T、肌球蛋白结合蛋白H;肌酸激酶、磷酸丙糖异构酶;过氧化物氧化还原酶、磷脂酰乙醇胺结合蛋白;组蛋白、甲基转移酶。[结论]电刺激后9种蛋白质通过4条途径影响电刺激后嫩度变化,包括糖酵解代谢途径、钙激活中性蛋白酶途径、溶酶体途径和氧化应激途径。电刺激通过通过4条途径影响嫩度的信号通路表明,牛肉嫩化与氧化、凋亡有密切联系;电刺激在一定程度上抑制增殖,加速氧化和凋亡,加快嫩化。

The Proteomic Analysis of Beef Tenderness after Electrical Stimulation

Objective] To research the effects of electrical stimulation (ES) on beef protein in the mature process after slaughter.[Method] The differential proteins were identified using the system of two-dimensional electrophoresis gels on muscle longissimus to analysis the relations to tenderness in this system.Differential protein spots with significant degradation during muscle longissimus ES were analyzed after 1 and 3 d of slaughtering.[Result] Compared with no ES samples, twelve protein spots were down-regulated significantly at 1 and 3 d postmortem as a result of electrical stimulation.These proteins were identified as nine types:desmin, troponin T alpha isoform, myosin binding protein H, cre-atine kinase, triosephosphate isomerase, peroxiredoxin-6, phosphatidylethanolamine-binding protein, histone H3.3-like isoform 2, methyl-transferase.[Conclusion] Proteins of nine types affects tenderness as a result of electrical stimulation through four pathways including glycolyt-ic metabolic pathway, calpains pathway, lysosomal pathway, and oxidative stress pathway.These pathways indicate that meat tenderness is closely related to oxidation and apoptosis, electrical stimulation inhibites proliferation, accelerates oxidation and apoptosis and finally acceler-ates meat tenderization.