Abstract

Nylon 5 and nylon 6,5 are recently explored as new commercial polyamides, of which the monomer includes δ-valerolactam. In this study, a novel catalytic activity of lysine 2-monooxygenase (DavB) was explored to produce δ-valerolactam from l-pipecolic acid (L-PA), functioning as oxidative decarboxylase on a cyclic compound. Recombinant Escherichia coli BS01 strain expressing DavB from Pseudomonas putida could synthesize δ-valerolactam from l-pipecolic acid with a concentration of 90.3 mg/L. Through the co-expression of recombinant apoptosis-inducing protein (rAIP) from Scomber japonicus, glucose dehydrogenase (GDH) from Bacillus subtilis, Δ¹-piperideine-2-carboxylae reductase (DpkA) from P. putida and lysine permease (LysP) from E. coli with DavB, δ-valerolactam was produced with the highest concentration of 242 mg/L. α-Dioxygenases (αDox) from Oryza sativa could act as a similar catalyst on l-pipecolic acid. A novel δ-valerolactam synthesis pathway was constructed entirely via microbial conversion from feedstock lysine in this study. Our system has great potential in the development of a bio-nylon production process.

Key points

• DavB performs as an oxidative decarboxylase on L-PA with substrate promiscuity.

• Strain with rAIP, GDH, DpkA, LysP, and DavB coexpression could produce δ-valerolactam.

• This is the first time to obtain valerolactam entirely via biosynthesis from lysine.

中文翻译：

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从原料赖氨酸生产聚酰胺单体δ-戊内酰胺的大肠杆菌的代谢工程

摘要

尼龙5和尼龙6,5最近被作为新型商业聚酰胺开发，其中的单体包括δ-戊内酰胺。在这项研究中，研究了赖氨酸2-单加氧酶（DavB）的新型催化活性，可从1-哌酸（L-PA）产生δ-戊内酰胺，并在环状化合物上起氧化脱羧酶的作用。表达恶臭假单胞菌DavB的重组大肠杆菌BS01菌株可从1-哌酸中合成δ-戊内酰胺，浓度为90.3 mg / L。通过从重组的细胞凋亡诱导蛋白的共表达（rAIP）鲐鱼，葡萄糖脱氢酶（GDH）从枯草芽孢杆菌，Δ ¹用DavB从恶臭假单胞菌得到β-哌啶-2-羧基还原酶（DpkA），从大肠杆菌得到赖氨酸通透酶（LysP），产生δ-戊内酰胺，其最高浓度为242 mg / L。稻（Oryza sativa）的α-双加氧酶（αDox）可以充当1-哌酸的类似催化剂。在这项研究中，完全通过原料赖氨酸的微生物转化构建了一种新型的δ-戊内酰胺合成途径。我们的系统在开发生物尼龙生产工艺方面具有巨大潜力。

关键点

• DavB在L-PA上起氧化脱羧酶的作用，并带有底物混杂。

•带有rAIP，GDH，DpkA，LysP和DavB共表达的菌株可产生δ-戊内酰胺。

•这是第一次完全通过赖氨酸的生物合成获得戊内酰胺。