Brayden Kell, a PhD candidate in the Biological Physics group, received the annual “Best Paper by a Graduate Student” award from the University of Toronto Mississauga’s Department of Chemical and Physical Sciences (CPS).

The award recognizes Brayden’s paper Noise properties of adaptation-conferring biochemical control modules, which was published in Proceedings of the National Academy of Sciences of the United States of America (PNAS). The paper is co-authored by former UofT Physics undergraduate Ryan Ripsman (now MD-PhD student at UBC) and Prof. Andreas Hilfinger of the Department of Physics and CPS.

The research describes how cellular control systems can simultaneously regulate average molecular abundances and spontaneous fluctuations around averages. Previous work suggested that achieving precise adaptation in biochemical networks came at the expense of increased stochastic variability (“noise”) around average behaviour. In this study Kell, et al. establish to the contrary that this adaptation vs. noise suppression trade-off is a singular limit of perfect adaptation. In contrast, this research shows that systems in the biologically realistic near-perfect adaption regime can achieve arbitrary precision and significant noise suppression, so long as cells can pay the corresponding energetic cost. Additionally, the paper proposes an alternative feedback topology which both overcomes the trade-off in the idealized perfect adaptation limit and has improved noise properties in the biologically realistic near-perfect regime. These results revise fundamental limits on biological robustness and suggest design principles for biological feedback design that may be preferable in synthetic biology applications.

More information here: Noise properties of adaptation-conferring biochemical control modules | PNAS