Abstract

The synthesis and degradation of biopolymers are cardinal reactions that take place to maintain homeostasis in biosystems. Fundamental biological reactions can be reproduced in vitro by means of enzyme-mediated processes. Recently, bioprocesses have been extensively adopted to synthesize representative biopolymers, including aliphatic polyesters, e.g., polyhydroxyalkanoate (PHA). In particular, the protein engineering of enzymes involved in PHA synthesis has made a great impact on the tailor-made synthesis of polymer materials with high performance. Biopolymers can also be synthesized in vitro by enzyme-catalyzed polymerization using synthetic enzymes and depolymerase-mediated reverse reactions. We will describe these advanced topics from the viewpoint of the boundary field between chemistry and biotechnology.

Keywords: Biopolymer, polyhydroxyalkanoate (PHA), PHA synthase, enzyme evolution, PHB depolymerase, lipase