Biophysics Seminar Series

The Biophysics Virtual Seminar Series presents:

Dr. Oleg Igoshin - Professor of Bioengineering & BioSciences, Associate Chair of Bioengineering, Rice University

“Understanding Trade-offs in Biological Error Correction”

Join us on Zoom: https://umich.zoom.us/j/96475935279

Abstract: High accuracy of major biological processes relies on the ability of the participating enzymatic molecules to preferentially select the correct substrate from a pool of chemically similar substrates by activating the so-called proofreading mechanisms. While the importance of such mechanisms is widely accepted, it is still unclear how evolution has optimized the biological systems with respect to their characteristic properties. We developed a comprehensive first-passage theoretical framework that allowed us to quantitatively investigate the trade-offs between four properties of enzymatic systems namely, error, speed, noise and energy dissipation. Within this framework, we simultaneously analyzed speed and accuracy of several fundamental biological processes, including DNA replication, tRNA charging, and tRNA selection during the translation. The results indicate that contrary to typical assumptions speed-accuracy trade-off is not always observed. However, when the trade-off is present, the biological systems tend to optimize the speed rather than the accuracy of the processes, as long as the error level is tolerable. When systems function in the regime where no speed-accuracy trade-off is observed, constraints due to energy dissipation in the proofreading play a key role. Our theory demonstrates a universal Pareto front in error-dissipation trade-off and shows how naturally selected kinetic parameters position their system close to this boundary. Our findings, therefore, provide a new system-level picture of how complex biological processes are able to function so fast with a high accuracy and low dissipation.