FIG. 4.

Alignment of the predicted amino acid sequences of complete ORFs identified in the Nichols tprK locus in five T. pallidum isolates, showing seven regions of heterogeneity (V₁ to V₇). Shaded areas indicate sequence identity, and broken line show the gaps in the alignment. NicholsGen, Nichols strain sequence as reported in the T. pallidum genome sequence; NicholsSea, sequence of the Nichols strain maintained in our laboratory. Bal 7, Bal 73-1, and Sea 81-4 are street isolates (Table 1). Additional numbers indicate the clone designations from each isolate. All sequences are from amplicons obtained with the F5-S and F3-As primers which bind the tprK flanking regions; therefore, no primer binding sites are included in this alignment.