Killing curves result from direct Gillespie simulations and are here compared with the static disorder approximation, Eq. (16). (

**a**) Ergodic regime. Parameters are the same as in , with

*k*_{0} = 5. In this case, no biphasic behaviour is apparent. The dashed red line corresponds to the slope of a single exponential killing with

and

43.2 nM. Panel (

**b**) shows different parameter sets characterizing the weakly non-ergodic regime. Parameter sets for the simulation were: (

**Red**)

*k*_{1} = 2.0⋅10

^{−7},

*k*_{2} = 1.0,

*γ*_{1} = 0.01,

*γ*_{2} = 4⋅10

^{−5} (all units in sec

^{−1}),

*T*_{0} = 2100 (sec),

*κ* = 1.0 (nM)

^{−1},

*V*_{0} = 1.7 fl,

*k*_{0} = 5; (

**Blue**)

*k*_{1} = 1.0⋅10

^{−6},

*k*_{2} = 1.0,

*γ*_{1} = 0.01,

*γ*_{2} = 4⋅10

^{−5} (all units in sec

^{−1}),

*T*_{0} = 2100 (sec),

*κ* = 1.0 (nM)

^{−1},

*V*_{0} = 1.7 fl,

*k*_{0} = 5; (

**Black**)

*k*_{1} = 1.0⋅10

^{−6},

*k*_{2} = 10.0,

*γ*_{1} = 0.01,

*γ*_{2} = 4⋅10

^{−5} (all units in sec

^{−1}),

*T*_{0} = 2100 (sec),

*κ* = 1.0 (nM)

^{−1},

*V*_{0} = 1.7 fl,

*k*_{0} = 5. The values for the mean number of bursts

*a*, and for the mean burst size

*b* were fitted from the corresponding protein distribution and used to evaluate the static disorder approximation (16), indicated with dashed lines. The corresponding values of

*a* and

*b* are reported in the legend box for ease of reading. Notice the regularly spaced jolts, more apparent during the fast killing phase, corresponding to the majority of cells dividing at regular intervals

*T*_{0}. The biphasic behaviour of the killing curve depends qualitatively on both

*a* and

*b*. The lower the mean number of bursts

*a*, the longer the initial killing phase, and the smaller the persister population, while the larger the mean burst size

*b*, the flatter the persister tail. In general, within the present model persistence requires small

*a*’s and large

*b*’s.

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