FIG. 2.

Oxidative and heat shock induction after cell plating. Cells (derivatives of MC4100) were grown in LB, sampled in the exponential phase (OD₆₀₀ = 0.5), and plated on LBA (see Materials and Methods). The expression level of β-galactosidase was measured as described in Materials and Methods and divided by the culturable cell number. (A) Oxidative stress induction; (B) heat shock induction. Experiments were repeated at least three times, and the standard deviations were always below 20%.