生体触媒の連携が実現する”一気通貫型”の乳酸ポリマー生合成プロセス : 乳酸重合酵素の発見から物性解析まで

Poly(lactic acid)

Poly(lactic acid) (PLA) is the most widespread biobased plastic with excellent transparency. Such biobased plastics are expected to be an alternative to petroleum-derived materials. Although PLA is currently produced from fermentative lactate (LA) via chemical polymerization using heavy metal catalysis, we developed a new bioprocess producing LA-based polyester by one-pot reaction. The breakthrough for establishing this process was the discovery of lactate-polymerizing enzyme (LPE). LPE is capable of synthesizing LA-based polyesters with extremely high enantiomer excess. Moreover, the LA-based copolyesters incorporating PHA constituents showed improved flexibility. Therefore, the microbial LA-based polyester is a potent candidate for an environmental friendly plastic.