Related Experiment Video
Updated: Jun 13, 2026

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Chain transfer reaction catalyzed by various polyhydroxyalkanoate synthases with poly(ethylene glycol) as an
Satoshi Tomizawa1, Yuta Saito, Manami Hyakutake
1Department of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan.
Abstract:
Polyhydroxyalkanoate (PHA) synthases catalyze chain transfer (CT) reaction after polymerization reaction of PHA by transferring PHA chain from PHA synthase to a CT agent, resulting in covalent bonding of CT agent to PHA chain at the carboxyl end. Previous studies have shown that poly(ethylene glycol) (PEG) is an effective exogenous CT agent. This study aimed to compare the effects of PEG on CT reaction during poly[(R)-3-hydroxybutyrate] [P(3HB)] synthesis by using six PHA synthases in Escherichia coli JM109. The synthesized P(3HB) polymers were characterized in terms of molecular weight and end-group structure. Supplementation of PEG to the culture medium reduced P(3HB) molecular weights by up to 96% due to PEG-induced CT reaction. The P(3HB) polymers were subjected to (1)H NMR analysis to confirm the formation of a covalent bond between PEG and P(3HB) chain at the carboxyl end. This study revealed the reactivity of PHA synthases to PEG with respect to CT reaction in E. coli.
More Related Videos
11:17Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction
Published on: January 19, 2016
15:33Microwave-assisted Functionalization of Poly(ethylene glycol) and On-resin Peptides for Use in Chain Polymerizations and Hydrogel Formation
Published on: October 29, 2013
Related Concept Videos
Radical Chain-Growth Polymerization: Overview
Radical Chain-Growth Polymerization: Mechanism
Cationic Chain-Growth Polymerization: Mechanism
Step-Growth Polymerization: Overview
Many natural and synthetic polymers are produced by...
Free-Radical Chain Reaction and Polymerization of Alkenes
Anionic Chain-Growth Polymerization: Mechanism