Evolutionary engineering of microbial enzyme that regulates the monomer composition in lactate-based polymer

2015 Fiscal Year Final Research Report

• Project/Area Number: 26660080
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Applied biochemistry
• Research Institution: Hokkaido University
• Principal Investigator: TAGUCHI SEIICHI 北海道大学, 工学(系)研究科(研究院), 教授 (70216828)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: ポリヒドロキシアルカン酸 / 乳酸ポリマー / 乳酸分率 / アセトアセチルCoA還元酵素 / 進化工学 / 速度論的解析 / ポリマー物性 / コリネ型細菌

Outline of Final Research Achievements

Microbial synthetic system for lactate (LA)-based polymer, as an advanced member of microbial polyester (polyhydroxyalkanoate) family, was already established by development of lactate-polymerizing enzyme. In order to regulate the monomer composition in P(LA-co-3-hydroxybutyrate (3HB)) copolymer, I have applied evolutionary engineering to NADPH-dependent acetoacetyl-CoA reducatase (PhaB) through the plate assay-based enzyme evolution program. As the result, I obtained two beneficial PhaB enzymes with increased activities that can also increased microbial polymer production. Acquired beneficial properties of these evolved P(3HB) enzymes can be accounted for by flexibility increase in the substrate-related region based on the tertiary structure bearing two domains.

Free Research Field

酵素進化工学