在酵母d-阿斯巴达酸氧化酶中的基质特异性的结构引导工程
Sota Zaitsu1, Daiki Imanishi1, Shouji Takahashi1
1Department of Materials Science and Bioengineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188, Japan.
Journal of bioscience and bioengineering
|March 7, 2026
概括
研究人员设计了酵母d-阿斯巴达酸氧化酶 (DDO) 来选择性地检测特定的d-氨基酸. 这一突破使得用于生物标志物开发的复杂混合物中d-histidine或d-phenylalanine的精确量化成为可能.
科学领域:
- 生物化学 生化学
- 酶学 是一种酶学.
- 蛋白质工程是指蛋白质工程.
背景情况:
- 对d-氨基酸的选择性量化对于生物学研究和诊断至关重要.
- 目前使用d-氨基酸氧化酶 (DAAO) 和d-酸氧化酶 (DDO) 的酶定量在混合样本中缺乏对单个d-氨基酸的特异性.
研究的目的:
- 为了确定酵母中的基质识别决定因素Vanrija humicola DDO (ChDDO).
- 为了设计ChDDO的基质特异性,用于选择性d-氨基酸检测.
- 为分析应用开发量身定制的生物催化剂.
主要方法:
- 进行X射线晶体学以确定ChDDO结构.
- 位点定向的突变发生改变活体位点残留物.
- 模拟分子动力学以研究酶动力学.
- 酶性测试用于评估基质特异性和运动参数.
主要成果:
- 在ChDDO中,Arg243被确定为控制基质特异性的关键残留物.
- 突变Arg243取消了d-酸盐的活性,并引入了d-histidine和d-phenylalanine的活动.
- 第二位点突变进一步细化了特异性,产生了对d-histidine或d-phenylalanine有选择性的变异.
- 工程变体精确量化了含有17种其他d-氨基酸的复杂混合物中的目标d-氨基酸.
结论:
- 涉及Arg243的独特封闭机制可能会调节ChDDO中的基质吸收.
- 结构引导工程成功地将DDO转化为选择性生物催化剂.
- 这种方法提供了一个开发定制酶的途径,用于生物技术和诊断中的精确d-氨基酸量化.
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