Pleurotus geesteranus 蛋白质分离物的结构和功能作为pH值的函数
Jiafeng Chen1, Shilang Chen1, Qianwang Zheng1
1Department of Bioengineering, College of Food Science, South China Agricultural University, Guangzhou, China.
Journal of food science
|November 4, 2024
概括
在低pH下,Pleurotus geesteranus蛋白质分离物 (PGPI) 由于结构变化而表现出较差的水溶性. 降低pH值会诱导有序的蛋白质结构,影响诸如保持水和乳化等功能性质.
科学领域:
- 食品科学 食品科学 食品科学
- 蛋白质化学 蛋白质化学
- 生物化学 生物化学
背景情况:
- 可食用的蛋白具有食品应用的潜力.
- 性提取-酸性沉通常会产生难以溶解的蛋白质.
- 在酸性降水过程中发生的结构变化还不太清楚.
研究的目的:
- 研究pH对Pleurotus geesteranus蛋白分离物 (PGPI) 的结构和功能的影响.
- 了解在酸沉的蛋白中溶解性差的原因.
- 开发一种高度水溶性的PGPI.
主要方法:
- 取,透析和冷干燥以制备PGPI.
- 对PGPI氨基酸组成和分子量分布 (SDS-PAGE) 的分析.
- 在pH范围内测量泽塔潜力,粒子大小,光强度和二次结构 (α-螺旋,β-叶).
主要成果:
- PGPI含有丰富的必需和芳香氨基酸,大多数蛋白质<45kDa.
- PGPI的同电点 (pI) 是4.3;颗粒大小从中性pH远离增加.
- 降低pH值会降低α螺旋,增加β片含量,改变光,表明结构更加有序.
- 含有SS键的含量和H0在pH4附近达到峰值,与结构变化相关.
结论:
- 降低pH值会诱导PGPI中有序的蛋白质结构,这解释了 poor可溶性.
- 结构变化显著影响PGPI的功能性质 (保持水/油,泡,乳化).
- 透析和冷干燥可以产生更易溶解的PGPI,但依赖pH的结构变化仍然至关重要.
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