Figure 4

Detection of the expression of yhcS by Northern blot. Three different B. subtilis strains were grown in LB medium and aliquots were analysed by Northern blot using either yhcS (upper panel), ywpE (middle panel) or dnaK antisense RNA (lower panel, loading control). +, strain NDH31/pNDH33-ywpE-yhcS where both genes coding for putative sortases were artificially expressed from an IPTG-dependent promoter; -, strain NDH31 where both putative sortase genes have been deleted. Lanes 2 to 10, aliquots from wild type strain 1012 were withdrawn at 2, 4, 6, 8 and 10 h after inoculation.