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bioRxiv · 10.1101/000448

Design and implementation of a synthetic biomolecular concentration tracker

Victoria Hsiao·Emmanuel LC de los Santos·Weston R Whitaker·John E Dueber·Richard M Murray
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Abstract

As a field, synthetic biology strives to engineer increasingly complex artificial systems in living cells. Active feedback in closed loop systems offers a dynamic and adaptive way to ensure constant relative activity independent of intrinsic and extrinsic noise. In this work, we design, model, and implement a biomolecular concentration tracker, in which an output protein tracks the concentration of an input protein. Synthetic modular protein scaffold domains are used to colocalize a two-component system, and a single negative feedback loop modulates the production of the output protein. Using a combination of model and experimental work, we show that the circuit achieves real-time protein concentration tracking in Escherichia coli and that steady state outputs can be tuned.

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Victoria Hsiao, Emmanuel LC de los Santos, Weston R Whitaker, John E Dueber, Richard M Murray. 2013-11-15. Design and implementation of a synthetic biomolecular concentration tracker. https://doi.org/10.1101/000448

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