Characterization of a rationally engineered phaCAB operon with a hybrid promoter design

Iain Bower; Bobby Wenqiang Chi; Matthew Ho Wai Chin; Sisi Fan; Margarita Kopniczky; Jemma Pilcher; James Strutt; Richard Kelwick; Alexander Webb; Kirsten Jensen; Guy-Bart Stan; Richard Kitney; Paul Freemont

doi:10.1101/006106

bioRxiv · 10.1101/006106

Characterization of a rationally engineered phaCAB operon with a hybrid promoter design

Iain Bower·Bobby Wenqiang Chi·Matthew Ho Wai Chin·Sisi Fan·Margarita Kopniczky·Jemma Pilcher·James Strutt·Richard Kelwick·Alexander Webb·Kirsten Jensen·Guy-Bart Stan·Richard Kitney·Paul Freemont

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Abstract

Biopolymers, such as poly-3-hydroxy-butyrate (P(3HB)) are produced as a carbon store in an array of organisms and exhibit characteristics which are similar to oil-derived plastics, yet have the added advantages of biodegradability and biocompatibility. Despite these advantages, P(3HB) production is currently more expensive than the production of oil-derived plastics, and therefore more efficient P(3HB) production processes are required. In this study, we describe the model-guided design and experimental characterization of several engineered P(3HB) producing operons. In particular, we describe the characterization of a novel hybrid phaCAB operon that consists of a dual promoter (native and J23104) and RBS (native and B0034) design. P(3HB) production was around six-fold higher in hybrid phaCAB engineered Escherichia coli in comparison to E. coli engineered with the native phaCAB operon from Ralstonia eutropha H16. The hybrid phaCAB operon represents a step towards the more efficient production of P(3HB), which has an array of applications from 3D printing to tissue engineering.

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Iain Bower, Bobby Wenqiang Chi, Matthew Ho Wai Chin, Sisi Fan, Margarita Kopniczky, Jemma Pilcher, James Strutt, Richard Kelwick, Alexander Webb, Kirsten Jensen, Guy-Bart Stan, Richard Kitney, Paul Freemont. 2014-06-09. Characterization of a rationally engineered phaCAB operon with a hybrid promoter design. https://doi.org/10.1101/006106

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