FIG 2.
yejM569 lowers lipopolysaccharide (LPS) levels and mutations that suppress yejM569 increase LPS. (A and B) Tenfold serial dilutions of the indicated strains containing a plasmid expressing wild-type (WT) yejM from an arabinose-inducible promoter were grown on LB containing 0.2% arabinose or 0.05% fucose at 30°C. (A) The yciMV43G yejM569 double mutant fails to grow unless a wild-type copy of yejM is expressed. All strains contain the ycjM::Tn10 marker. (B) The lpxC101 yejM569 double mutant cannot grow unless wild-type yejM is expressed. (C and D) LPS levels were determined by immunoblot analysis using antibodies that recognize LPS. Antibodies recognizing RpoA were used as a loading control. LPS levels in the yejM569 mutant are decreased. Relative quantification indicates LPS levels compared to the levels in the wild type. (C) Suppressor mutations in yciM increase LPS levels in the yejM569 mutant. All strains contain ycjM::Tn10. (D) Suppressor mutations in lpxC increase LPS in the yejM569 mutant. All strains contain the leuB::Tn10 allele. Data are representative of three independent experiments. *, stop codon; fs, frameshift.