Sootla A.,Center for Synthetic Biology and Innovation |
Strelkowa N.,Boehringer Ingelheim |
Ernst D.,University of Liege |
Barahona M.,Imperial College London |
Stan G.-B.,Center for Synthetic Biology and Innovation
Proceedings of the IEEE Conference on Decision and Control | Year: 2013
In this paper, we consider the periodic reference tracking problem in the framework of batch-mode reinforcement learning, which studies methods for solving optimal control problems from the sole knowledge of a set of trajectories. In particular, we extend an existing batch-mode reinforcement learning algorithm, known as Fitted Q Iteration, to the periodic reference tracking problem. The presented periodic reference tracking algorithm explicitly exploits a priori knowledge of the future values of the reference trajectory and its periodicity. We discuss the properties of our approach and illustrate it on the problem of reference tracking for a synthetic biology gene regulatory network known as the generalised repressilator. This system can produce decaying but long-lived oscillations, which makes it an interesting application for the tracking problem. ©2013 IEEE.
Kelwick R.,Center for Synthetic Biology and Innovation |
Kopniczky M.,Center for Synthetic Biology and Innovation |
Bower I.,Center for Synthetic Biology and Innovation |
Chi W.,Center for Synthetic Biology and Innovation |
And 13 more authors.
PLoS ONE | Year: 2015
Biopolymers, such as poly-3-hydroxybutyrate (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 would be desirable. In this study, we describe the model-guided design and experimental validation of several engineered P(3HB) producing operons. In particular, we describe the characterization of a hybrid phaCAB operon that consists of a dual promoter (native and J23104) and RBS (native and B0034) design. P(3HB) production at 24 h 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. Additionally, we describe the utilization of non-recyclable waste as a low-cost carbon source for the production of P(3HB). © 2015 Kelwick et al.