生物催化烯烃不对称胺羟化构建手性β-氨基醇及协同机制探究

Chiral β-amino alcohols are a very important class of compounds. This structural motif is common to a variety of fine chemicals, natural products and bioactive compounds. Aminohydroxylation of alkenes is one of the most potential alternatives for synthesis of chiral β-amino alcohols. Traditional chemical methods give the poor selectivity, the expense and toxicity of catalyst and cause environmental pollution. Bicatalysis as a high selectivity and environment-friendly method become frontier fields of scientific research. In this proposal, a cascade biocatalysis method for aminohydroxylation of alkenes to synthesize chiral β-amino alcohols was constructed with four high active and high selective enzymes. Highly efficient cofactor regeneration system in this cascade biocatalysis system will be constructed by enzymatic methods. The reaction influence cofactors and Michaelis-Menten kinetics will be studied, and the cooperative mechanism of this cascade biocatalysis will be clarified. The Substrate channelling will be presented by co-immobilized enzyme methods. On these bases, a highly efficient Escherichia coli whole cell aminohydroxylation cell factory will be constructed. The research achievement will provide a high selective, economical, high efficient new method for synthesis of chiral β-amino alcohols, and provide theoretical guidance and practical reference for construction of a low cost and large scale cascade biocatalysis in synthesis of chiral compounds, has a strong theoretical and practical value.

手性β-氨基醇是一类非常重要的化合物，是合成许多精细化学品、天然产物和生物活性化合物的中间体。胺羟化烯烃是手性β-氨基醇合成最直接有效的方法之一，传统化学法胺羟化烯烃选择性低、催化剂昂贵且有毒、造成环境污染等问题。生物催化选择性高、对环境友好而成为国际研究前沿和热点。本项目以手性β-氨基醇绿色合成为导向，拟通过多酶一锅煮级联催化烯烃胺羟化构建手性β-氨基醇；通过酶法在反应体系内构建高效辅酶循环再生机制；通过对反应影响因素及反应动力学的考察，提出多酶级联催化烯烃胺羟化协同机制，并通过共固定化策略实现多酶催化底物通道效应；最后通过基因工程方法，构建高效大肠杆菌整体细胞催化烯烃胺羟化细胞工厂。研究将为手性β-氨基醇的绿色合成开发出新的高选择性、经济、高效的催化合成途径，并为建立低成本、规模化生物级联催化制备手性化合物提供理论指导和实践参考，具有很强的理论和应用价值。