嵌入在蛋白质序列中的D-氨基酸如何改变其消化能力:在作为标的模型上测试的消化酶的行为
Francesca Accardo1, Barbara Prandi1, Luca Dellafiora1
1Department of Food and Drug, University of Parma, Parco Area delle Scienze, 27/A, 43124 Parma, Italy.
Food chemistry
|July 4, 2024
概括
蛋白质中D-氨基酸的存在可以通过影响素等关键酶来减缓消化. 这种种族化会影响蛋白质.
科学领域:
- 生物化学 生物化学
- 蛋白质溶解是一种蛋白质溶解.
- 营养科学 营养科学
背景情况:
- D-氨基酸自然存在,可以纳入蛋白质.
- 蛋白质消化依赖于特定的酶,如氨酸,氨酸和化学氨酸.
- 纳入D-氨基酸对消化酶活性的影响尚未完全理解.
研究的目的:
- 研究D-氨基酸在链中的D-氨基酸如何随着时间的推移影响主要消化酶的活性.
- 为了确定D-氨基酸的位置 (分离点与远处位置) 是否会影响酶的行为.
- 为了比较D-氨基酸对胃 (素) 和肠道 (素,胆素) 酶的影响.
主要方法:
- 一个模型 (β-乳球蛋白片段48-60) 通过系统地用D-氨基酸替代L-氨基酸来合成.
- 随着时间的推移,通过素,素和化学素对这些改性的酶性水解进行了监测.
- 根据D-氨基酸替代物的位置和数量分析了酶活性的变化.
主要成果:
- D-氨基酸替代物改变了消化酶的活性,即使不是在直接裂解部位.
- 素的活性受到D-氨基酸存在的显著影响,与素和化学素相比.
- 这些发现表明,种族化可以降低蛋白质的消化能力,根据涉及的特定酶和氨基酸而产生不同的影响.
结论:
- 饮食蛋白质中氨基酸的种族化可以通过降低蛋白质消化能力来降低营养价值.
- 消化酶功能,特别是素,对D-氨基酸的存在敏感.
- 上部消化道可能比下部肠道更容易受到种族化的影响.
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