PT  - JOURNAL ARTICLE
AU  - Edward J. Hancock
AU  - Diego A. Oyarzún
TI  - Stabilisation of Antithetic Control via Molecular Buffering
AID  - 10.1101/2021.04.18.440372
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.04.18.440372
4099  - http://biorxiv.org/content/early/2021/09/29/2021.04.18.440372.short
4100  - http://biorxiv.org/content/early/2021/09/29/2021.04.18.440372.full
AB  - A key goal in synthetic biology is the construction of molecular circuits that robustly adapt to perturbations. Although many natural systems display perfect adaptation, whereby stationary molecular concentrations are insensitive to perturbations, its de novo engineering has proven elusive. The discovery of the antithetic control motif was a significant step toward a universal mechanism for engineering perfect adaptation. Antithetic control provides perfect adaptation in a wide range of systems, but it can lead to oscillatory dynamics due to loss of stability, and moreover, it can lose perfect adaptation in fast growing cultures. Here, we introduce an extended antithetic control motif that resolves these limitations. We show that molecular buffering, a widely conserved mechanism for homeostatic control in nature, stabilises oscillations and allows for near-perfect adaptation during rapid growth. We study multiple buffering topologies and compare their performance in terms of their stability and adaptation properties. We illustrate the benefits of our proposed strategy in exemplar models for biofuel production and growth rate control in bacterial cultures. Our results provide an improved circuit for robust control of biomolecular systems.Competing Interest StatementThe authors have declared no competing interest.