Evolving titer and regulations of the secondary metabolic pathways

2020 Fiscal Year Final Research Report

• Project Area: Creation of Complex Functional Molecules by Rational Redesign of Biosynthetic Machineries
• Project/Area Number: 16H06450
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: Chiba University
• Principal Investigator: Umeno Daisuke 千葉大学, 大学院工学研究院, 教授 (00400812)
• Project Period (FY): 2016-06-30 – 2021-03-31
• Keywords: 進化分子工学 / 合成生物学 / 生合成 / ランダム変異 / テルペノイド / スクリーニング / 共進化 / 酵素

Outline of Final Research Achievements

Mix-and-match of biosynthetic genes, followed by extensive directed evolution round has enabled biosynthesis of various non-natural or even extra-natural compounds. To improve the titers of these artificial pathways, they should be nicely embedded into the metabolic networks of host organisms. In this project, (1) we tried to co-evolve exogenous terpenoid pathway and endogenous precursor pathway to improve both to the unprecedented level. Multi-round evolution isolated terpene synthase mutants with improved cellular activity, alongside with greatly improved precursor suppliers. Also, (2) we developed technology to create enzyme-based biosensors, which enable screening-based pathway design for various natural/unnatural compounds. Based on the evolutionary platform for sensors and enzymes, we have established pathways toward more than 50 novel compounds with unique biophysical/ photochemical properties.

Free Research Field

進化分子工学

Academic Significance and Societal Importance of the Research Achievements

高効率なテルペノイドの前駆体の供給経路を完成させることによって，さまざまな稀少テルペンの生合成研究が可能となるほか，産業的価値が認められる数多くの有価テルペンの高効率生産と社会実装に貢献できた。また，テルペン酵素そのものの活性改良や機能発散のスキームを完成させたことによって，テルペン生産のもう一つのボトルネックである酵素そのものの脆弱性・性能の低さを克服する足掛かりができた。また，任意性の高い生合成中間体のバイオセンサの製作技術を完成させ，それを使った生合成改良が可能となった。この手法を多用することで，生合成経路の再デザインの歩留まりが大きく高まるものと期待される。