Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada T6G 2P5.
J Agric Food Chem. 2012 Jan 11;60(1):272-82. doi: 10.1021/jf2033973. Epub 2011 Dec 20.
The market of specialty eggs, such as omega-3-enriched eggs, organic eggs, and free-range eggs, is continuously growing. The nutritional composition of egg yolk can be manipulated by feed diet; however, it is not known if there is any difference in the composition of egg white proteins among different egg varieties. The purpose of the study was to compare the egg white proteins among six different egg varieties using proteomics analysis. Egg white proteins were analyzed using two-dimensional gel electrophoresis (2-DE), and 89 protein spots were subjected to LC-MS/MS. A total of 23 proteins, belonging to Gallus gallus , were identified from 72 detected protein spots. A quiescence-specific protein precursor in egg white was identified for the first time in this study. Significant differences in the abundant levels of 19 proteins (from 65 protein spots) were observed among six egg varieties. Four proteins, ovalbumin-related protein Y, cystatin, avidin, and albumin precursor, were not different among these six egg varieties. These findings suggest that the abundance, but not the composition, of egg white proteins varied among the egg varieties.
特种蛋品市场（如富含欧米伽-3 的蛋、有机蛋和散养蛋）持续增长。蛋黄的营养成分可以通过饲料来操纵；然而，不同蛋品品种的蛋清蛋白组成是否存在差异尚不清楚。本研究旨在使用蛋白质组学分析比较六种不同蛋品品种的蛋清蛋白。使用二维凝胶电泳（2-DE）分析蛋清蛋白，对 89 个蛋白点进行 LC-MS/MS 分析。从 72 个检测到的蛋白点中鉴定出 23 种属于 Gallus gallus 的蛋白。本研究首次在蛋清中鉴定到一种静止特异性蛋白前体。在六种蛋品品种中观察到 19 种蛋白（来自 65 个蛋白点）的丰度存在显著差异。四种蛋白（卵清白蛋白相关蛋白 Y、半胱氨酸蛋白酶抑制剂、亲和素和白蛋白前体）在这六种蛋品品种中没有差异。这些发现表明，蛋清蛋白的丰度而非组成在不同蛋品品种之间存在差异。
