高氧气调包装贮藏牛排肉色稳定性的蛋白质组学

Proteomic Study of the Color Stability of High-Oxygen Modi?ed Atmosphere Packaged Steak during Chilled Storage

为进一步了解高氧气调包装牛排贮藏过程中肉色稳定性变化的机理,本研究比较了腰背最长肌牛排在各贮藏时间点(0、5、10、15 d)的肉色指标变化以及蛋白质组学变化。结果发现高氧气调包装牛排的肉色稳定性随贮藏时间延长不断降低,这可能是贮藏期间牛排的高铁肌红蛋白还原能力和氧气消耗率显著下降所致;通过蛋白质组学分析,共发现了20个在贮藏过程中发生显著变化的差异蛋白,其中有15个蛋白与肉色密切相关,它们主要是一些参与糖酵解和能量代谢的酶类(丙酮酸激酶、3-磷酸甘油醛脱氢酶、果糖-二磷酸醛缩酶、果糖-1,6-二磷酸酶同工酶2、苹果酸脱氢酶和黄素还原酶),这些代谢酶的表达量随贮藏时间延长发生了不同程度的下调,减少了烟酰胺腺嘌呤二核苷酸和还原型烟酰胺腺嘌呤二核苷酸磷酸的产生,进而降低了肉色稳定性;另外,高氧气调包装贮藏过程中肉色稳定性的降低可能也与肌红蛋白的表达量下调有关;高氧环境还可能会促使抗氧化蛋白2、热休克蛋白以及DJ-1蛋白的表达量上调以抵御肉品的氧化应激反应,这些蛋白也都与肉色指标紧密相关。这些发现表明贮藏期间高氧气调包装对牛排蛋白质组的影响将直接决定其肉色稳定性的变化。

The objective of this study was to understand the mechanisms underlying changes in the color stability of high-oxygen modified atmosphere packaged(HiOx-MAP)steak during storage.The variations in meat color traits and sarcoplasmic proteome of longissimus dorsi steaks after different storage periods(0,5,10 and 15 days)were compared.The results suggested that the color stability of steaks decreased over time,which may be due to a significant decrease in metmyoglobin reducing activity(MRA)and oxygen consumption rate(OCR)during storage.The proteomic analysis revealed that a total of 20 differentially abundant proteins were identified during storage,15 proteins of which were closely correlated with meat color traits and were identified as enzymes involved in glycolytic and energy metabolism(pyruvate kinase,glyceraldehyde-3-phosphate dehydrogenase,fructose-bisphosphate aldolase,fructose-1,6-bisphosphatase isozyme 2,malate dehydrogenase,and flavin reductase).The expression levels of these metabolic enzymes were downregulated to different extents with increasing storage time,thereby reducing NADH and NADPH levels and consequently meat color stability.Moreover,the decrease in meat color stability also may be related to the down-regulation of myoglobin expression during storage.Oxidative environments could induce the expression of peroxiredoxin-2,heat shock protein and protein DJ-1 to resist oxidative stress,and these proteins were closely correlated with meat color parameters.These findings indicate that the influence of high-oxygen modified atmosphere packaging on meat proteome will directly determine changes in meat color stability throughout storage.