Cascade synthesis of rare ketoses by whole cells based on L-rhamnulose-1-phosphate aldolase
Cascade synthesis of rare ketoses by whole cells based on L-rhamnulose-1-phosphate aldolase
复制标题
基于L-鼠李酮糖-1-磷酸醛缩酶的全细胞级联合成稀有酮糖
DOI：
10.1016/j.enzmictec.2019.109456
复制
发表时间：
2020-02-01
影响因子：
3.4
通讯作者：
Gao, Xiao-Dong
中科院分区：
文献类型：
--
作者：
Chen, Zhou;Li, Zijie;Gao, Xiao-Dong
磷酸二羟丙酮 (DHAP) 依赖性醛缩酶由于其独特的立体选择性，在稀有酮糖的生产中表现出重要的价值。作为一个具体的例子，我们开发了一种高效的大肠杆菌全细胞生物催化级联系统，其中稀有的酮糖由丰富的甘油产生，并由基于 L-鼠李酮糖-1-磷酸醛缩酶 (RhaD) 的四种酶催化。对于连续添加D-甘油醛的半连续生物转化，一旦D-甘油醛被消耗，D-山梨糖和D-阿洛酮糖的最终产量分别为15.30 g/L和6.35 g/L。此外，8小时时D-山梨糖和D-阿洛酮糖的最大转化率和生产率分别为99%和1.11 g/L/h。当用L-甘油醛代替D-异构体时，L-果糖的最终产率为16.80 g/L。此外，8小时时L-果糖的最大转化率和产率分别为95%和1.08 g/L/h。该合成平台还与其他各种醛兼容，从而可以从甘油生产许多其他高价值化学品。
Dihydroxyacetone phosphate (DHAP)-dependent aldolases demonstrate important values in the production of rare ketoses due to their unique stereoselectivities. As a specific example, we developed an efficient Escherichia coli whole-cell biocatalytic cascade system in which rare ketoses were produced from abundant glycerol and catalyzed by four enzymes based on L-rhamnulose-1-phosphate aldolase (RhaD). For the semicontinuous bioconversion in which D-glyceraldehyde was continuously added, once D-glyceraldehyde was consumed, the final yields of D-sorbose and D-psicose were 15.30 g/L and 6.35 g/L, respectively. Moreover, the maximum conversion rate and productivity of D-sorbose and D-psicose were 99% and 1.11 g/L/h at 8 h, respectively. When L-glyceraldehyde was used instead of the D-isomer, the final yield of L-fructose was 16.80 g/L. Furthermore, the maximum conversion rate and productivity of L-fructose were 95% and 1.08 g/L/h at 8 h, respectively. This synthetic platform was also compatible with other various aldehydes, which allowed the production of many other high-value chemicals from glycerol.