Combinatorial expression of different β-carotene hydroxylases and ketolases in Escherichia coli for increased astaxanthin production. (1st November 2019)

• Record Type: Journal Article
• Authors: Wu, Yuanqing; Yan, Panpan; Liu, Xuewei; Wang, Zhiwen; Tang, Ya-Jie; Chen, Tao; Zhao, Xueming
• Is Part Of: Journal of industrial microbiology & biotechnology. Volume 46:Number 11(2019)
• Page Start: 1505
• Page End: 1516
• Publication Date: 2019-11-01
• Subjects: Astaxanthin -- Combinatorial expression -- Artificial operon -- Fusion protein -- Bifunctional enzymes; Industrial microbiology -- Periodicals; 660.62
• DOI: 10.1007/s10295-019-02214-1
• Languages: English
• ISSNs: 1367-5435

Abstract

Abstract: In natural produced bacteria, β-carotene hydroxylase (CrtZ) and β-carotene ketolase (CrtW) convert β-carotene into astaxanthin. To increase astaxanthin production in heterologous strain, simple and effective strategies based on the co-expression of CrtZ and CrtW were applied in E. coli . First, nine artificial operons containing crtZ and crtW genes from different sources were constructed and, respectively, introduced into E. coli ZF237T, a β-carotene producing host. Among the nine resulting strains, five accumulated detectable amounts of astaxanthin ranging from 0.49 to 8.07 mg/L. Subsequently, the protein fusion CrtZ to CrtW using optimized peptide linkers further increased the astaxanthin production. Strains expressing fusion proteins with CrtZ rather than CrtW attached to the N-terminus accumulated much more astaxanthin. The astaxanthin production of the best strain ZF237T/CrtZAs -(GS)1 -WBs was 127.6% and 40.2% higher than that of strains ZF237T/ crtZ As W Bs and ZF237T/ crtZ Bs W Ps, respectively. The strategies depicted here also will be useful for the heterologous production of other natural products.