Rapid regulations of metabolic reactions in Escherichia coli via
light-responsive enzyme redistribution
Abstract
Protein-based condensates have been proposed to accelerate biochemical
reactions by enriching reactants and enzymes simultaneously. Here, we
engineered those condensates into a Photo-Activated Switch in E. coli
(PhASE) to regulate enzymatic reactions via tuning the spatial
correlation of enzymes and substrates. In this system, scaffold proteins
undergo liquid-liquid phase separation (LLPS) to form light-responsive
compartments. Tethered with a light-responsive protein, enzymes of
interest (EOIs) can be recruited by those compartments from cytosol
within only a few seconds after a pulse of light induction and fully
released in 15 minutes. Furthermore, we managed to enrich small
molecular substrates simultaneously with enzymes in the compartments and
achieved the acceleration of luciferin and catechol oxidation by 2.3
folds and 1.6 folds, respectively. We also developed a quantitative
model to guide the further optimization of this de-mixed regulatory
system. Our tool can thus be used to study the rapid redistribution of
proteins, and reversibly regulate enzymatic reactions in E. coli.