Fig. 5.

Expression of the sarX gene in the different wild-type strains at various phases of growth. Northern blots were hybridized with 550 bp DNA fragments containing the coding region of the sarX gene. A total of 10 μg cellular RNA was loaded in each lane. Lanes 1–6, total cellular RNA from the growing cultures at OD₆₀₀ 0.3, 0.7, 1.1, 1.4, 1.7 and overnight (stationary) (Fig. 1b). P1 and P2 indicate the major (0.5 knt) and minor (1.5 knt) transcripts of the sarX locus (Manna & Cheung, 2006a). The region containing 23S and 16S rRNA of the ethidium bromide-stained gel used for blotting is shown as a loading control. The third and sixth panels from the top represent Western blots of intracellular extracts from the different wild-type strains probed with anti-SarX polyclonal antibodies. Equivalent amounts of extracts (20 μg) from the different phases of growth (OD₆₀₀ ∼0.7, early exponential; OD₆₀₀ ∼1.1, exponential; OD₆₀₀ ∼1.7, post-exponential) were used to detect SarX expression.