Park Seong-Hee, Lee Kyusung, Jang Jae Woo, Hahn Ji-Sook
School of Chemical and Biological Engineering , Seoul National University , 1 Gwanak-ro, Gwanak-gu , Seoul 08826 , Republic of Korea.
BIO Research Institute , CJ CheilJedang , Suwon 16495 , Republic of Korea.
ACS Synth Biol. 2019 Feb 15;8(2):346-357. doi: 10.1021/acssynbio.8b00388. Epub 2019 Jan 10.
Shinorine, a mycosporine-like amino acid (MAA), is a small molecule sunscreen produced in some bacteria. In this study, by introducing shinorine biosynthetic genes from cyanobacteria Nostoc punctiform into Saccharomyces cerevisiae, we successfully constructed yeast strains capable of producing shinorine. Sedoheptulose 7-phosphate (S7P), an intermediate of the pentose phosphate pathway, is a key substrate for shinorine biosynthesis. To increase the S7P pool, xylose, which is assimilated via the pentose phosphate pathway, was used as a carbon source after introducing xylose assimilation genes from Scheffersomyces stipitis into the shinorine-producing strain. The resulting xylose-fermenting strain produced a trace amount of shinorine when cells were grown in glucose, but shinorine production was dramatically increased by adding xylose in the medium. Shinorine production was further improved by modulating the pentose phosphate pathway through deleting TAL1 and overexpressing STB5 and TKL1. The final engineered strain JHYS17-4 produced 31.0 mg/L (9.62 mg/g DCW) of shinorine in the optimized medium containing 8 g/L of xylose and 12 g/L of glucose, demonstrating that S. cerevisiae is a promising host to produce this natural sunscreen material.
肌醇六磷酸，一种类菌孢素氨基酸（MAA），是某些细菌产生的一种小分子防晒剂。在本研究中，通过将点状念珠藻的肌醇六磷酸生物合成基因导入酿酒酵母，我们成功构建了能够产生肌醇六磷酸的酵母菌株。景天庚酮糖7-磷酸（S7P）是磷酸戊糖途径的中间产物，是肌醇六磷酸生物合成的关键底物。为了增加S7P库，在将树干毕赤酵母的木糖同化基因导入产肌醇六磷酸菌株后，将通过磷酸戊糖途径同化的木糖用作碳源。所得的木糖发酵菌株在葡萄糖中生长时产生微量的肌醇六磷酸，但通过在培养基中添加木糖，肌醇六磷酸的产量显著增加。通过缺失TAL1并过表达STB5和TKL1来调节磷酸戊糖途径，进一步提高了肌醇六磷酸的产量。最终的工程菌株JHYS17-4在含有8 g/L木糖和12 g/L葡萄糖的优化培养基中产生了31.0 mg/L（9.62 mg/g DCW）的肌醇六磷酸，表明酿酒酵母是生产这种天然防晒材料的有前景的宿主。
