In Vitro Analysis of d-Lactyl-CoA-Polymerizing Polyhydroxyalkanoate Synthase in Polylactate and Poly(lactate- co-3-hydroxybutyrate) Syntheses.

Engineered d-lactyl-coenzyme A (LA-CoA)-polymerizing polyhydroxyalkanoate synthase (PhaC1STQK) efficiently produces poly(lactate- co-3-hydroxybutyrate) [P(LA- co-3HB]) copolymer in recombinant Escherichia coli, while synthesizing tiny amounts of poly(lactate) (PLA)-like polymers in recombinant Corynebacterium glutamicum. To elucidate the mechanisms underlying the interesting phenomena, in vitro analysis of PhaC1STQK was performed using homo- and copolymerization conditions of LA-CoA and 3-hydroxybutyryl-CoA. PhaC1STQK polymerized LA-CoA as a sole substrate.