Cofactor supply for bacterial cell growth and polyhydroxyalkanoate synthesis concomitant with enzymatic oxidation of phosphite

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K14689
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Applied microbiology
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Tsuge Takeharu 東京工業大学, 物質理工学院, 准教授 (70332260)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 亜リン酸 / 補酵素 / ポリエステル合成

Outline of Final Research Achievements

In this study, the effect of NADPH supply on bacterial cell growth and polyhydroxyalkanoate (PHA) production was investigated using a phosphite dehydrogenase double mutant, which catalyzes oxidation of phosphite to phosphate with the generation of NADH and NADPH. In an in vitro assay using purified enzymes, PHA polymerization was observed only when phosphite and the double mutant enzyme were present, confirming that NADPH was supplied for PHA synthesis. In an in vivo assay, the presence of phosphite and the double mutant enzyme did not influence the yield of PHA under normal growth conditions. However, PHA yield increased 3.2-fold in non-growing cells compared to the control, suggesting that NADPH generation is coupled with PHA biosynthesis.

Free Research Field

高分子生合成