Yi Yulan, Sheng Huakai, Li Zhimin, Ye Qin
State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
BMC Biotechnol. 2014 May 19;14:44. doi: 10.1186/1472-6750-14-44.
Trans-4-hydroxy-L-proline (trans-Hyp), one of the hydroxyproline (Hyp) isomers, is a useful chiral building block in the production of many pharmaceuticals. Although there are some natural biosynthetic pathways of trans-Hyp existing in microorganisms, the yield is still too low to be scaled up for industrial applications. Until now the production of trans-Hyp is mainly from the acid hydrolysis of collagen. Due to the increasing environmental concerns on those severe chemical processes and complicated downstream separation, it is essential to explore some environment-friendly processes such as constructing new recombinant strains to develop efficient process for trans-Hyp production.
In this study, the genes of trans-proline 4-hydroxylase (trans-P4H) from diverse resources were cloned and expressed in Corynebacterium glutamicum and Escherichia coli, respectively. The trans-Hyp production by these recombinant strains was investigated. The results showed that all the genes from different resources had been expressed actively. Both the recombinant C. glutamicum and E. coli strains could produce trans-Hyp in the absence of proline and 2-oxoglutarate.
The whole cell microbial systems for trans-Hyp production have been successfully constructed by introducing trans-P4H into C. glutamicum and E. coli. Although the highest yield was obtained in recombinant E. coli, using recombinant C. glutamicum strains to produce trans-Hyp was a new attempt.
反式-4-羟基-L-脯氨酸(反式-Hyp)是羟脯氨酸(Hyp)的异构体之一,是许多药物生产中有用的手性结构单元。尽管微生物中存在一些反式-Hyp的天然生物合成途径,但其产量仍然过低,无法扩大规模用于工业应用。到目前为止,反式-Hyp的生产主要来自胶原蛋白的酸水解。由于对这些苛刻化学过程和复杂下游分离的环境问题日益关注,探索一些环境友好的过程,如构建新的重组菌株以开发高效的反式-Hyp生产工艺至关重要。
在本研究中,分别从不同来源克隆了反式脯氨酸4-羟化酶(反式-P4H)基因,并在谷氨酸棒杆菌和大肠杆菌中表达。研究了这些重组菌株生产反式-Hyp的情况。结果表明,来自不同来源的所有基因均已积极表达。重组谷氨酸棒杆菌和大肠杆菌菌株在无脯氨酸和2-氧代戊二酸的情况下均可产生反式-Hyp。
通过将反式-P4H引入谷氨酸棒杆菌和大肠杆菌,成功构建了用于生产反式-Hyp的全细胞微生物系统。尽管重组大肠杆菌的产量最高,但使用重组谷氨酸棒杆菌菌株生产反式-Hyp是一种新的尝试。