FIG. 1.

Selection for LPS phase variants in the presence of LL-37/hCAP18. Nontypeable clinical isolate H233 shows a dose-dependent killing caused by LL-37/hCAP18. Numbers of bacteria surviving treatment for 60 min in the concentration of LL-37/hCAP18 indicated on the x axis are shown in panel A. The horizontal arrowhead along the y axis indicates the total number of bacteria present at the beginning of the incubation period (0 min). H233 is a mixed population of phase variants with (solid symbols) and without (open symbols) ChoP or Galα1-4Gal on their LPS (37). Survivors showed a dose-related increase in the proportion of ChoP⁺ compared to ChoP⁻ phase variants as determined by colony immunoblotting (B). There was, however, no selection for phase variants with or without the Galα1-4Gal structure (C). Results are the mean of a representative experiment in duplicate.