TritionalshiftsofEscherichiacoliB/rtorichermediahavebeenanalyzedinsynchronouslygrowingandexponential-phasepopulations.Earlyperturbationsinthetimingofcelldivisionwereobserved.Attheslowgrowth,divisionpro-gressedatarateequaltoorlessthanthepreshiftrateforabout1h.Atintermediategrowth,bothdelaysandaccelerationindivisionwereobserved.Theextentoftheperturbationdependedupontheageofthecellsatthetimeoftheshiftandthecompositionofthepreshiftandpostshiftmedia.TheperturbationwasdifferentinthetwosubstrainsofE.coliB/r I got this from http://jb.asm.org/content/136/2/631.full.pdf hopefully it helps you
