Extended Data Fig. 4.

H₂O₂ increases degradation rate by ClpXP that, in combination with transcriptional increase at the lux promoter, decreases variability in the oscillator period. (a) There is a significant decrease in the degradation time due to H₂O₂ (experimental). (b) This is due to effective increase in ClpXP degradation rate (experimental). (c) H₂O₂ activation of lux promoter alone would only increase the amplitude of quorum clock oscillations. Similarly, H₂O₂ -dependent increase in ClpXP activity results only in steeper degradation and longer inter-pulse duration. Combination of the two effects leads to increase in amplitude and decrease in inter-pulse duration, which matches experiments (model). (d) Individually the two H₂O₂ effects do little to lower the quorum clock period CV, which is reduced when both are present (model).