Biosynthesis of alfa-methylated polyhydroxyalkanoates by constructing artificial pathway and characterization of their thermal properties

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H03640
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 64030:Environmental materials and recycle technology-related
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Tsuge Takeharu 東京工業大学, 物質理工学院, 教授 (70332260)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 生分解性プラスチック / バイオプラスチック / ポリヒドロキシアルカン酸

Outline of Final Research Achievements

Biosynthesis of α-methylated polyhydroxyalkanoates (PHAs) was investigated by constructing an artificial pathway in Escherichia coli. By employing a novel ketothiolase Acat3 derived from nematodes, a precursor was synthesized by Claisen condensation of acetyl-CoA and propionyl-CoA, which was then reduced by reductase PhaB to serve as a substrate for the PHA synthase PhaC. As a result, it succeeded in incorporating α-methylated monomers up to approximately 16 mol% into PHA copolymers. The thermal properties of these polymers were characterized, and their crystallization behavior was compared with that of conventional PHAs.

Free Research Field

生体高分子

Academic Significance and Societal Importance of the Research Achievements

微生物ポリエステルは、バイオマスを原料とすることによる持続可能性と優れた自然環境中での生分解性から、今後、広く普及が期待されるプラスチックのひとつである。一方で次世代の微生物ポリエステルには、実用的な材料物性を担保しつつ、かつ、結晶化挙動に優れることが求められる。今回合成法を開発したαメチル化PHAは、α炭素のメチル化によって結晶化が迅速に進むようになり、この材料の有用性を示すことができた。これらの成果は、高性能な材料の分子設計を行う上で重要な知見として役立てることができる。