Microbial production process for stereospecific synthesis of nitrogen-containing chiral compounds

手性化合物是医药等领域的重要中间体，由于其高度的立体专一性和环境友好性，生物催化合成手性化合物受到了广泛的关注。另一方面，含氮手性化合物对于许多有用化合物的合成也是重要的，例如药物和农用化学品。(1)3-奎宁环酮还原酶是从根癌农杆菌中分离得到的一种还原酶，并对其进行了详细的结构鉴定。该酶属于SDR超家族。根据3-奎宁环酮还原酶的氨基酸序列，克隆了该酶的编码基因，并在大肠杆菌中高效表达。coli大肠杆菌此外，E.构建了共表达3-奎宁环酮还原酶和葡萄糖脱氢酶基因的大肠杆菌，并在此基础上构建了不对称还原法生产（R）-3-奎宁环醇的系统。建立了coil细胞。(2)红平红球菌氨基醇脱氢酶是一种很有前途的生产d-伪麻黄碱的酶。而d-伪麻黄碱对该酶有抑制作用。为了提高氨基醇脱氢酶的活性，采用易错PCR技术对氨基醇脱氢酶进行了随机突变。最后，几种突变酶在高浓度d-伪麻黄碱存在下显示出活性。氨基醇脱氢酶是由几种氨基醇诱导的。通过对氨基醇脱氢酶基因的遗传和转录分析，推测GntR家族转录调控因子的同源ORF可能是R.红原

Chiral compounds are useful intermediates for the production of pharmaceuticals and so on. Because of high stereospecificity and environmental aspects, biocatalytic production of chiral compounds has been attracting considerable attention. On the other hand, nitrogen-containing chiral compounds are also important for the synthesis of many useful compounds, such as pharmaceuticals and agrochemicals.(1) 3-Quinuclidinone reductase was isolated from Agrobacterium tumefaciens, and characterized in some details. The enzyme belongs to SDR superfamily. Based on amino acid sequence of the enzyme, the gene encoding 3-quinuclidinone reductase was cloned and overexpressed in E. coli transformant cells. Furthermore, E. coli coexpressing 3-quinuclidinone reductase and glucose dehydrogenase genes was constructed, and the production system for (R)-3-quinuclidinol via asymmetric reduction with E. coil transformant cells was established.(2) Aminoalcohol dehydrogenase from Rhodococcus erythropolis is a promising enzyme for the production of d-pseudoephedrine. However, the enzyme was inhibited by d-pseudoephedrine. To improve aminoalcohol dehydrogenase, a random mutagenesis was performed by error-prone PCR. Finally, several mutant enzymes showing the activity in the presence of high concentration of d-pseudoephedrine. Aminoalcohol dehydrogenase was induced by several aminoalcohols. Through the genetic and transcriptional analysis of aminoalcohol dehydrogenase gene, a homologous orf of the GntR family transcriptional regulators was suggested to be a negative transcriptional regulator of aminoalcohol dehydrogenase gene in R. erythropolis.