In Vivo Characterization and Application of the PHA Synthase from for the Biosynthesis of Polyhydroxyalkanoate Containing 4-Hydroxybutyrate.

Polyhydroxyalkanoate (PHA) is a biodegradable thermoplastic naturally synthesized by many microorganisms, and the PHA synthase (PhaC) is known to be the key enzyme involved in determining the material properties and monomer composition of the produced PHA. The ability to exploit widely distributed, commonly found soil microorganisms such as to synthesize PHA containing the lipase-degradable 4-hydroxybutyrate (4HB) monomer will allow for convenient production of biocompatible and flexible PHA. Comparisons between the wild type and mutant strains, with and without a surface layer (S-layer), respectively, in terms of gene or amino acid sequences, synthase activity, granule morphology, and PHA productivity, revealed that the S-layer is the sole factor affecting PHA biosynthesis by .

Characterization of the depolymerizing activity of commercial lipases and detection of lipase-like activities in animal organ extracts using poly(3-hydroxybutyrate-co-4-hydroxybutyrate) thin film.

Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] is one of the polyhydroxyalkanoate (PHA) copolymers which can be degraded by lipases. In this study, the depolymerizing activity of different known commercial lipases was investigated via microassay using P(3HB-co-92 mol % 4HB) thin film as substrate. Non-enzymatic hydrolysis occurred under conditions in which buffers with pH 12 and 13 were added or temperature of 50 °C and above.