Fig 7.

Competitive index (CI) results. The data are from two CI experiments demonstrating the ratio of C12 to wild-type A3 strain (experiment 1) or C33 to wild-type A3 strain (experiment 2) during mixed infection. Individual mice were inoculated with lp28-3-deficient and wild-type spirochetes at a ratio of 1:1 (closed circles) or 1:1.25 (open circles). Each circle represents the CI calculated from reisolates from an individual mouse at the time point indicated. The ear (E), bladder (B), and tibiotarsal joint (J) tissues were harvested at a 4-week time point in experiment 1 and an 8-week time point in experiment 2, and the colony screening results from those tissues were used to determine the CI. Ear punch (EP) biopsy specimens were taken at 2 and 4 weeks postinoculation in the second experiment to determine spirochete ratios. For tick acquisition, the CI was determined from spirochetes isolated from ticks that fed on individual mice. Colony screening data for determination of the CI are presented in Tables S2 and S3 for CI for experiments 1 and 2, respectively.