FIG. 6.

Phylogenetic analysis of PapG I′-containing strains and comparator strains. Pearson correlation coefficient analysis of composite RAPD fingerprints from primers 1281, 1247, and 1254 was used to establish pairwise similarity relationships between strains, which were then used construct a dendrogram by UPGMA (51). Strains that contain papG allele I or I′ (asterisk) are shown in boldface. Strains of serogroups O4 (top) and O6 (bottom) are bracketed. Note that (papG allele I-containing) strain L31, which serologically is an O6 strain, is placed with the O6 comparator strains according to RAPD analysis. Strains J96, CP9, C367-82, and 7U constitute a “J96-like” subcluster within the larger O4 cluster. (Strains are shown in the same sequence in Table 1 as in this RAPD-based dendrogram.)