Masoodi Tariq Ahmad, Shafi Gowhar
Institute of Genetics and Hospital for Genetic Diseases, Begumpet, Hyderabad 500016, India.
Bioinformation. 2010 Mar 31;4(9):430-5. doi: 10.6026/97320630004430.
Nowadays, the quality of any food used for human consumption is, to a considerable extent, considered by its possible contribution to the maintenance or improvement of the consumer's health. In developed countries there is increasing interest in goat milk and its derivates, the quality of which is considered of special importance in the light of current tendencies favouring healthy eating. In particular, goat's milk is a hypoallergenic alternative to cow's milk in the human diet. In the present work, we studied the casein alpha S1 and S2 proteins of cow, goat and sheep for comparative analysis. We found that the amino acid sequence of these proteins is almost same in goat and sheep but there are several changes at different base pairs when these two sequences are compared with cow. Prediction of secondary structures (GOR) was performed for alpha s1 and s2 proteins to gain functional insights. Our in silico study revealed considerable identity in chemical properties between goat and sheep but a considerable dissimilarity in cow with goat and sheep casein proteins. Moreover, the effect amino acid change on secondary structures in the three species is discussed. There was no significant difference found between goat and sheep alpha S1 and S2 proteins, so naturally both will be having same properties. The study concludes that sheep milk is another convenient alternative for the cow milk allergic children.
如今，任何供人类食用的食品质量在很大程度上都取决于其对维持或改善消费者健康的潜在贡献。在发达国家，人们对山羊奶及其衍生物的兴趣与日俱增，鉴于当前倡导健康饮食的趋势，其质量被认为具有特殊重要性。特别是，在人类饮食中，山羊奶是牛奶的一种低过敏性替代品。在本研究中，我们对牛、山羊和绵羊的αS1和αS2酪蛋白进行了比较分析。我们发现，这些蛋白质在山羊和绵羊中的氨基酸序列几乎相同，但与牛的序列相比，在不同碱基对处存在一些变化。对αS1和αS2蛋白质进行了二级结构预测（GOR），以获得功能方面的见解。我们的计算机模拟研究表明，山羊和绵羊的酪蛋白在化学性质上有相当高的一致性，但与山羊和绵羊的酪蛋白相比，牛的酪蛋白有相当大的差异。此外，还讨论了氨基酸变化对这三个物种二级结构的影响。山羊和绵羊的αS1和αS2蛋白质之间没有发现显著差异，所以自然地两者具有相同的特性。该研究得出结论，羊奶是牛奶过敏儿童的另一种便利替代品。
