FIG 7.

Site-specific mutation of fasX can separate the streptokinase- and adhesin-regulating activities of FasX. (A) Schematic showing the locations of two C-to-G SNPs present in plasmids pFasX.ska.loop (green) and pFasX.UC.loop (purple). The red nucleotides are those that base pair to ska mRNA to regulate streptokinase expression. The blue nucleotides are those that base pair to the adhesin-encoding mRNAs (prtF1, prtF2, and pilus). (B) Western blot analyses assaying the ability of the mutant fasX alleles present within plasmids pFasX.ska.loop and pFasX.UC.loop to complement PrtF1, PrtF2, and SKA expression in the mutant derivative M28ΔFasX. A stained membrane was used as a loading control for the cell wall fraction in Western blot analyses, while expression of the non-FasX-regulated protein SpeC was used as a control for the secreted fraction in Western blot analyses.