在一个旧的黄色酶中,N-终端的切断 (N-) 和定向质子转移使得可调节的高效生产 (R) 或 (S)
Jie Zhang1, Yueshu Li1, Hui Gao1
1The Key Laboratory of Industrial Biotechnology, Ministry of Education, Laboratory of Applied Microorganisms and Metabolic Engineering, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
International journal of biological macromolecules
|February 14, 2024
概括
研究人员增强了老黄色酶 (OYE) 的活性,用于生物催化生产 (R) - citronellal,这是 (-) -menthol的关键前体. 工程 OYE 变种实现了高立体选择性和效率,克服了以前的限制.
科学领域:
- 生物催化剂是一种生物催化剂.
- 酵素工程是什么? 酶工程是什么
- 有机合成 有机合成
背景情况:
- 旧黄色酶 (OYE) 对于生产 (R) - 烯,这是广泛使用的化合物 (-) - 醇的前体至关重要.
- 目前的OYE活动限制了高效的生物催化剂生产,特别是来自混合 (E/Z) - 基质.
研究的目的:
- 在 (R) - 氨酸生产中改造Corynebacterium glutamicum OYE (CgOYE) 以提高活性,稳定性和立体选择性.
- 制定一项整体战略,以提高OYE在生物催化剂中的性能.
主要方法:
- 合理的设计涉及CgOYE的N端截断,以提高活性,热稳定性和pH耐受性.
- 截断突变体 (N31-CgOYE) 的位点定向突变发生,以实现高 (R) 和 (S) 类固醇选择性.
- 使用工程化CgOYE变体进行生物催化降解racemic (E/Z) -citral.
主要成果:
- 切断CgOYE增强了它的活性,热稳定性和pH耐受性.
- 三种特定突变将N31-CgOYE转化为高度 (R) 和 (S) 立体选择性酶.
- 工程CgOYE实现了高达99%的反体过剩 (ee) 和转换,用于从racemic混合物中生产 (R) -citronellal.
结论:
- 涉及N端截断和向突变发生的新策略显著提高了OYE生物催化剂的性能.
- 工程酶有效地从混合基质中产生 (R) - ,克服了以前的限制.
- 氨酸残留物在酶选择性"调节性关"中发挥着关键作用,为酶工程提供了一种多功能方法.
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