FIG 1 .

PEA decoration of N. gonorrhoeae lipid A confers a competitive advantage during genital tract infection. The competitive index (CI) was equal to [FA1090 ΔlptA or C′FA1090 ΔlptA/FA1090 (output)]/[FA1090 ΔlptA or C′FA1090 ΔlptA/FA1090 (input)]. (A) Competitive infections in female BALB/c mice (n = 7) with FA1090 ΔlptA and FA1090; (B) female BALB/c mice (n = 7) with C′FA1090 ΔlptA and FA1090; (C) male volunteers (n = 6) with FA1090 ΔlptA and FA1090. Note the different y axis scale in panel C, imposed by the limit of detection of 100-fold-decreased fitness in experimental human infections. (A and C) A CI of <1 indicates that the mutant is less fit than the wild type. Solid circles indicate mice from which both wild-type N. gonorrhoeae FA1090 and FA1090 ΔlptA were recovered (A) and both wild-type N. gonorrhoeae FA1090 and C′FA1090 ΔlptA/FA1090 were recovered (B). Open circles indicate infected mice or men from whom only wild-type N. gonorrhoeae FA1090 was recovered (A and C) or only C′FA1090 ΔlptA was recovered (B). Horizontal bars indicate geometric mean CIs.