Tailored Biosynthesis of Olefinic Medium-Chain-Length Poly[(R)-3-hydroxyalkanoates] in Pseudomonas putida GPo1 with Improved Thermal Properties

TLDR: In this paper, a chemostat culture of Pseudomonas putida GPo1 under well-defined dual-(C,N)-nutrient limited growth conditions was used to produce tailor-made copolymers.

Abstract: Mixtures of 5-phenylvalerate, octanoate, and 10-undecenoate were fed to a chemostat culture (dilution rate = 0.1 h-1) of Pseudomonas putida GPo1 under well-defined dual-(C,N)-nutrient limited growth conditions. Five new, tailor-made copolymers were produced and consisted of poly(3-hydroxy-5-phenylvalerate-co-3-hydroxyalkanoates-co-3-hydroxy-ω-alkenoates), poly(HP-co-HA-co-HE), with increasing amounts of aromatic side chains (A, 0%; B, 3%; C, 19%; D, 42%; and E, 59%), approximately 10 mol % unsaturated side chains, and decreasing amounts of saturated side chains. On the basis of NMR analysis of polymer E, it was concluded that the incorporation of the substrates occurred randomly. The HP-content determined the glass transition temperature, which increased linearly from −38.7 °C for poly(0%HP-co-90%HA-co-10%HE) to −6.0 °C for poly(59%HP-co-31%HA-co-10%HE).