Fig 2.
The Δskp ΔfkpA double mutant exhibits an LptD assembly defect that is not due to loss of other LptD assembly factors. Cultures were grown to an OD600 of approximately 0.7 to 0.8. Whole-cell lysates were analyzed by SDS-PAGE and immunoblotted with the appropriate antibody. (A) A ΔsurA strain is included for comparison. Levels of TolC, LamB, and OmpA are unaffected by the loss of skp and fkpA. (B) Samples were analyzed by SDS-PAGE in sample buffer with (LptDRed) and without (LptDOx) 2-mercaptoethanol. “X-Band” is a cross-reacting band of approximately 55 kDa, shown here as a loading control. Levels of both oxidized and reduced LptD are decreased in the absence of Skp and FkpA. (C) The levels of proteins known to be important for LptD assembly are unchanged in the absence of Skp and FkpA.