直接非对称合成β分支芳α-氨基酸,使用工程氨酸氨基酶
Chenghai Sun1, Gen Lu2, Baoming Chen2
1Department of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, University of Greifswald, Greifswald, Germany. chenghai.sun23@outlook.com.
Nature communications
|September 26, 2024
概括
研究人员设计了氨氨酸氨酶 (PAL) 酶,以创建一种新的合成宝贵β分支芳α-氨基酸的新方法. 这种生物催化方法实现了高立体选择性和产量,克服了以前的合成挑战.
科学领域:
- 生物催化和酶工程 生物催化和酶工程
- 有机合成 有机合成
- 药用化学 医学化学
背景情况:
- β-分支芳香α-氨基酸是药品和天然产品中至关重要的成分.
- 这些化合物的现有合成途径通常由于立体化学挑战而复杂.
- 氨氨酸氨基酶 (PALs) 显示出不对称合成的潜力,但与特定基质作斗争.
研究的目的:
- 设计氨氨酶 (PAL) 变体,用于直接非对称合成β分支芳香α-氨基酸.
- 克服本地PAL酶的基质限制,特别是与β-甲基酸 (β-MeCA).
- 开发一种可扩展和高效的生物催化方法来生产这些有价值的氨基酸类似物.
主要方法:
- 进行广泛的计算分析以了解PAL基质的特异性.
- 位点定向的突变生成产生双 (PcPAL-L256V-I460V) 和三 (PcPAL-F137V-L256V-I460V) PAL变种.
- 优化了大肠杆菌的全细胞生物转化,用于扩大规模的合成.
- 计算模拟以阐明反应机制.
主要成果:
- 工程 PAL 变种成功合成了β-MeCA 和它的类似物.
- 对于十种不同的类似物来说,获得了高的二选择性 (dr>20:1) 和反选择性 (ee>99.5%).
- 在优化的全细胞生物转化系统中,产量在41-71%之间.
- 计算研究揭示了基质接受和立体选择性转换的机制.
结论:
- 工程 PAL 变种提供了一种高效和高度刻板选择的方法来合成 β 分支芳香 α-氨基酸.
- 这种生物催化方法克服了传统合成的局限性,为药物化学和药物发现提供了宝贵的工具.
- 这项研究证明了将计算设计与酶工程结合起来,创造新的生物催化剂的力量.
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