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

TL;DR

This study applies a flow-adapted Michaelis-Menten kinetic framework to bacterial biofilms in flow reactors, revealing how flow conditions enhance catalytic performance and biomass, aiding in system optimization.

Contribution

It introduces a standardized kinetic model for biofilm catalysis in flow reactors, enabling quantitative analysis and benchmarking of living catalytic systems.

Findings

Flow rate increases up to 50% in turnover rates.

Flow-induced enhancements linked to increased catalytic biomass.

Standardized kinetics improve system analysis and comparison.

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.