Pathway engineering for efficient biosynthesis of violaxanthin in Escherichia coli.

Pathway engineering for efficient biosynthesis of violaxanthin in Escherichia coli. Appl Microbiol Biotechnol. 2019 Oct 31;: Authors: Takemura M, Kubo A, Higuchi Y, Maoka T, Sahara T, Yaoi K, Ohdan K, Umeno D, Misawa N Abstract Carotenoids are naturally synthesized in some species of bacteria, archaea, and fungi (including yeasts) as well as all photosynthetic organisms. Escherichia coli has been the most popular bacterial host for the heterologous production of a variety of carotenoids, including even xanthophylls unique to photosynthetic eukaryotes such as lutein, antheraxanthin, and violaxanthin. However, conversion efficiency of these epoxy-xanthophylls (antheraxanthin and violaxanthin) from zeaxanthin remained substantially low. We here examined several factors affecting their productivity in E. coli. Two sorts of plasmids were introduced into the bacterial host, i.e., a plasmid to produce zeaxanthin due to the presence of the Pantoea ananatis crtE, crtB, crtI, crtY, and crtZ genes in addition to the Haematococcus pluvialis IDI gene, and one containing each of zeaxanthin epoxidase (ZEP) genes originated from nine photosynthetic eukaryotes. It was consequently found that paprika (Capsicum annuum) ZEP (CaZEP) showed the highest conversion activity. Next, using the CaZEP gene, we performed optimization experiments in relation to E. coli strains as the production hosts, expression vectors, and ribosome-binding site (RBS) sequences. ...
Source: Applied Microbiology and Biotechnology - Category: Microbiology Authors: Tags: Appl Microbiol Biotechnol Source Type: research