Figure 1

Effects of Hfq inactivation on the stability and the abundance of the rpsO transcripts. Comparison of the decay-rate of the rpsO mRNA in strains N3433 (wt), IBPC929 (hfq^-), N3433/pTX367 and N3433/pGEM3. Cultures were grown at 37°C to OD₆₀₀≈0.4, RNA was extracted from aliquots withdrawn after addition of rifampicin (500 μg/ml) (time intervals in min are indicated above the lanes) and then subjected to Northern blot analysis. The blots were hybridized with the rpsO probe and then with the probe for 5S RNA to normalize the RNA content per lane. RNA levels were quantified using a PhosphoImager; half-lives are indicated below each autoradiograph. Antibiotics were added when required.