FIG. 2.

Clustering analysis of tprK DNA sequences obtained directly from primary chancres of patients MD504, MD530, and MD55 (A) and from isolates that were propagated 4 (Sea 81-3), 6 (Sea 83-1), or 10 (Sea 84-2) times in rabbits (B). Cluster groups are made up of unique sequences from an individual patient or isolate, and are enclosed by a solid oval. Lowercase letters represent the unique sequences in each sample and, in panel A, numbers in parentheses indicate the number of sequenced plasmid clones that contain that sequence. In panel B, each plasmid clone contains a unique sequence. Trees were subject to 100 random bootstrap resamplings, and bootstrap numbers for major branches are shown. The marker bar represents a 1% difference in nucleotide sequences; within a given sample, there is greater genetic distance among rabbit-propagated sequences than among primary chancre sequences.