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arXiv · 1904.05412

A generalized kinetic framework applied to whole-cell catalysis in biofilm flow reactors clarifies performance enhancements

Mir Pouyan Zarabadi·Manon Couture·Steve J. Charette·Jesse Greener
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Abstract

A common kinetic framework for studies of whole-cell catalysis is vital for understanding and optimizing bioflow reactors. In this work, we demonstrate the applicability of a flow-adapted version of Michaelis-Menten kinetics to a catalytic bacterial biofilm. A three-electrode microfluidic electrochemical flow cell measured increased turnover rates by as much as 50% from a Geobacter sulfurreducens biofilm as flow rate was varied. Based on parameters from the applied kinetic framework, flow-induced increases to turnover rate, catalytic efficiency and device reaction capacity could be linked to an increase in catalytic biomass. This study demonstrates that a standardized kinetic framework is critical for quantitative measurements of new living catalytic systems in flow cells and for benchmarking against well-studied catalytic systems such as enzymes.

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Mir Pouyan Zarabadi, Manon Couture, Steve J. Charette, Jesse Greener. 2019-04-10. A generalized kinetic framework applied to whole-cell catalysis in biofilm flow reactors clarifies performance enhancements. https://arxiv.org/abs/1904.05412

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