Putative carotenoid genes expressed under the regulation of Shine–Dalgarno regions in Escherichia coli for efficient lycopene production

Objectives: Putative genes crtE, crtB, and crtI from Deinococcus wulumiqiensis R12, a novel species, were identified by genome mining and were co-expressed using the optimized Shine-Dalgarno (SD) regions to improve lycopene yield. Results: A lycopene biosynthesis pathway was constructed by co-expressing these three genes in Escherichia coli. After optimizing the upstream SD regions and the culture medium, the recombinant strain EDW11 produced 88 mg lycopene g⁻¹ dry cell wt (780 mg lycopene l⁻¹) after 40 h fermentation without IPTG induction, while the strain EDW without optimized SD regions only produced 49 mg lycopene g⁻¹ dry cell wt (417 mg lycopene l⁻¹). Conclusion: Based on the optimization of the upstream SD regions and culture medium, the yield of the strain EDW11 reached a high level during microbial lycopene production until now.