不特定蛋白酶的特定序列抑制
Leigh A Logsdon1, Adam R Urbach
1Department of Chemistry, Trinity University, 1 Trinity Place, San Antonio, Texas 78212, USA.
Journal of the American Chemical Society
|July 26, 2013
概括
黄瓜[7]uril (Q7) 特别抑制阿米诺酶N (APN),使得精确的基修饰. 这种合成宿主通过阻断N端氨基酸的去除,产生稳定的单个产品.
科学领域:
- 生物化学 生物化学
- 合成化学 合成化学
- 蛋白酶抑制可以抑制蛋白酶抑制.
背景情况:
- 氨基酶N (APN) 是一种非特异性的外酶.
- 合成宿主如黄[7]uril (Q7) 可以表现出对某些分子标的高度亲和力和特异性.
- 控制蛋白酶活性对于合成和分子识别至关重要.
研究的目的:
- 为了研究黄[7]uril (Q7) 对氨基酶N (APN) 的序列特异性抑制.
- 探索Q7在控制可预测基修饰的蛋白酶活性方面的潜力.
- 评估这种方法对的生产和分子识别的有用性.
主要方法:
- 使用液体色谱分析在Q7的存在下,APN的化转化.
- 进行结构-活性关系研究,以将N端氨基酸结合与Q7亲和力相关联.
- 评估Q7结合产品对蛋白质消化过程的稳定性.
主要成果:
- Q7特别与N端的氨 (Phe) 和4-氨基甲基氨 (AMPhe) 结合,抑制了APN.
- 在存在过多的Q7的情况下,APN可以定量地将五转化为二,而Q7则与N端残留物结合.
- 由此产生的Q7结合产品在24小时以上的时间内对蛋白质分解性消化具有完全的稳定性.
- 观察到N端氨基酸保护程度与其对Q7.7的亲和力之间存在直接相关性.
结论:
- Q7赋予了可预测的序列特异性到其他非特异性的APN.
- 这种方法可以通过控制蛋白酶活性来产生单个稳定的产品.
- APN-Q7相互作用可以发现高亲和度的表位,促进的分子识别.
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