一种不对称的还原酶,可以拦截由合作氧化酶in situ产生的基氨基酸
Jin Guo1, Melanie A Higgins1, Phillip Daniel-Ivad1
1Department of Chemistry , University of British Columbia , Vancouver , British Columbia V6T 1Z4 , Canada.
Journal of the American Chemical Society
|July 13, 2019
概括
这项研究描述了Bsp5,一种氨基酸还原酶,它将不稳定的乙烯基氨基酸转化为奇拉胺. 这一发现为d-氨基酸的生物催化合成开辟了新的途径.
科学领域:
- 生物化学
- 结构生物学
- 酵素学
背景情况:
- 在水性环境中,环胺是化学不稳定的,这限制了它们在生物催化中的使用.
- 现有的胺基还原酶主要处理稳定的循环胺基,限制各种性胺基的合成.
研究的目的:
- 在生物化学和结构上描述Bsp5,一种新型的氨基酸还原酶.
- 阐明Bsp5对乙烯基氨基酸的作用的结构基础.
- 探索Bsp5在生物催化应用中的潜力.
主要方法:
- 在1.6 Å分辨率下测定Bsp5与d-arginine和NADPH复合的X射线晶体学.
- 位点定向的突变发生,以确定酶活性的关键残留物.
- 生物化学测试以描述Bsp5的减少酶活性.
主要成果:
- 详细的生物化学和结构数据Bsp5,一个d-2-酸脱酶家族的氨基酸减少酶.
- 确定 Bsp5 的最小结构要求.
- 证明Bsp5可以处理来自替代氧化酶合作伙伴的产品,从而实现更广泛的基质范围.
结论:
- Bsp5有效地降低了伴侣氧化酶*in situ*产生的环亚氨基酸.
- 这些结构洞察力为工程Bsp5增强生物催化功能提供了基础.
- Bsp5氧化酶系统具有生物催化转化L-氨基酸到D-氨基酸的潜力.
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