FIG. 1.

Effect of SscB on the intracellular level of SseF. The secretion-deficient ssaV mutant strain (ZP18) and the ssaV sscB double-mutant strain (ZP41) carrying plasmids expressing either SseF-M45 (pZP281 and pZP546), SscBSseF-M45 (pZP284 and pZP549), SifB-M45 (pZP430), or SseJ-M45 (pZP492) were grown in the SPI-2-inducing MgM5 or MgM7 minimal medium, and protein expressions were either driven by the sseA promoter (A) or were induced by the addition of 1 mM arabinose (panel B). Bacteria were collected and lysed, and protein levels were determined as described in Materials and Methods.