FIGURE 4.
N-terminal lipid anchor of HxcQ is required for function. Analysis of LapA secretion in supernatant fractions from P. aeruginosa PAO1 wild type and ΔhxcQΔxcpQΔxphAΔxqhA mutant strains producing HxcQV5 and HxcQnlV5. Cellular (C) and extracellular (E) proteins separated on a 12% (w/v) SDS-polyacrylamide gels were stained with Coomassie Blue (upper panel) or immunoblotted for LapA detection (lower panel). The dots indicate Xcp-dependent exoproteins, whereas LapA is indicated by a triangle. The asterisk indicates a nonspecific band reacting with the LapA antiserum. This band is also present in a lapA mutant (not shown).