对虾冷藏期间骨架蛋白构象及磷酸化变化  

Changes in the Conformation and Phosphorylation of Cytoskeletal Proteins during the Refrigeration of Shrimp

作　　者：徐德峰 廖威龙 谭圳业 梁雨 廖建萌 陆大鹏 叶盛权[2] XU Defeng;LIAO Weiong;TAN Zhenye;LIANG Yu;LIAO Jianmeng;LU Dapeng;YE Shengquan(School of Ocean and Tropical Medicine,Guangdong Medical University,Zhanjiang 524023,China;College of Food Science and Technology,Guangdong Ocean University,Zhanjiang 524088,China;Zhanjiang Institute of Food and Drug Control,Zhanjiang 524031,China)

机构地区：[1]广东医科大学海洋与热带医学学院,广东湛江524023 [2]广东海洋大学食品科技学院,广东湛江524088 [3]湛江市食品药品研究所,广东湛江524031

出　　处：《广东海洋大学学报》2024年第6期80-90,共11页Journal of Guangdong Ocean University

基　　金：广东省基础与应用基础研究项目(2023A1515010852)。

摘　　要：【目的】分析对虾冷藏期间肌原纤维骨架蛋白构象及磷酸化水平变化,识别冷藏对虾肌肉软化关键结构蛋白,为品质监控提供靶标。【方法】测定4℃冷藏期间(0~120 h)凡纳滨对虾(Litopenaeus vannamei)水分分布、质子密度图谱、构象变化、蛋白质降解和磷酸化修饰情况,解析肌原纤维结构蛋白降解与肌肉软化的相关性。【结果】冷藏至120 h时,对虾肌肉质构参数(硬度、弹性、黏聚性和咀嚼性)显著下降至(2381.87±112.01)g、(0.66±0.09)mm、0.32±0.05和(504.46±122.07)g,而肌原纤维小片化指数显著上升至33.00±0.90;肌肉组织中自由水相对含量显著增加至36.87%±3.30%,表明肌原纤维呈现出间隙增大、断裂和结构松散的微观特征;肌原纤维α-螺旋相对含量显著下降至33.98%±1.70%,β-折叠和无规则卷曲相对含量显著上升至34.36%±1.13%和31.66%±0.57%;特征性紫外和荧光吸收光谱发生明显红移,吸收强度显著下降0.40±0.01和661.90±1.28;总体磷酸化水平显著下降至0.65±0.01。α=0.05。此外,肌球蛋白重链、肌间线蛋白、肌动蛋白和肌钙蛋白T的降解速率(k)分别为0.0050、0.0114、0.0044和0.0086 h^(-1),且肌间线蛋白和肌钙蛋白T与质构劣变相关性最高(r>0.90,P<0.001)。【结论】肌间线蛋白和肌钙蛋白T是对虾冷藏过程中肌肉软化的标志物,可用于监控对虾冷藏期间早期肌肉软化。【Objective】To analyze the changes in the conformation and phosphorylation of myofibrillar cytoskeletal proteins(Litopenaeus vannamei)during refrigeration,the key structural proteins involved in shrimp muscle softening were attempted to identify.【Methods】The attributes of water distribution,proton density mapping,conformational changes,protein degradation,and phosphorylation modifications of L.vannamei were measured during refrigerated storage at 4℃over a period of 0 to 120 hours.The correlation between myofibrillar protein degradation and muscle softening was explored.【Results】The significant decreases in shrimp muscle texture parameters(hardness,elasticity,cohesiveness,and chewiness)were determined after 120 hours of refrigeration,with values decreasing to(2381.87±112.01)g,(0.66±0.09)mm,0.32±0.05,and(504.46±122.07)g,respectively.Meanwhile,the myofibrillar fragmentation index increased significantly to 33.00±0.90.Additionally,the relative content of free water in the muscle tissue increased significantly to 36.87%±3.30%,indicating the myofibrils exhibited microscopic features such as enlarged gaps,fractures,and loose structure.The relative content ofα-helix in myofibrils decreased significantly to 33.98%±1.70%,while the relative contents ofβ-sheet and random coil increased significantly to 34.36%±1.13%and 31.66%±0.57%,respectively.Furthermore,characteristic UV and fluorescence absorption spectra showed a significant red shift,and the absorption intensity was significantly reduced to 0.40±0.01 and 661.90±1.28.Overall phosphorylation levels were significantly reduced to 0.65±0.01.α=0.05.Moreover,the degradation rates(k)for myosin heavy chain,desmin,actin,and troponin T were 0.0050,0.0114,0.0044,and 0.0086 h^(-1),respectively.Desmin and troponin T demonstrated the highest correlation with texture deterioration(r>0.90,P<0.001).【Conclusion】Desmin and troponin T can serve as the biomarkers of muscle softening and can be used to monitor the early muscle softening of refrigerated shrimp.

关 键 词：对虾 冷藏 肌肉软化 骨架蛋白 磷酸化水平 

分 类 号：TS254.1[轻工技术与工程—水产品加工及贮藏工程]