We analyze the transcriptomic response of the phytopathogenic enterobacterium Dickeya dadantii ihfA mutant to a DNA supercoiling relaxation shock using the gyrase inhibitor novobiocin. The shock was applied to Dickeya cells grown in minimal medium supplemented with sucrose, in exponential or transition to stationary phase, and in minimal medium with sucrose + PGA (a pectin derivative) in transition to stationary phase.