  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.
