Abstract:
:The tprK gene sequence of Treponema pallidum subspecies pallidum (T. pallidum) is heterogeneous within and among isolates. Heterogeneity in the tprK open reading frame is localized in seven discrete variable (V) regions, and variability results from apparent base changes, insertions or deletions. The TprK V regions are the focus of anti-TprK antibodies arising during infection. To test our hypothesis that V region sequences change during infection and passage, we developed a clonal isolate from the Chicago strain of T. pallidum and confirmed V region diversification during passage of this isolate. We describe the sequence anatomy of the seven V regions of tprK and the identification of putative donor sites for new V region sequences, and we propose a model for generation of new V regions by segmental gene conversion. These findings suggest that antigenic variation of TprK occurs in T. pallidum and may be important in immune evasion and persistence.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Centurion-Lara A,LaFond RE,Hevner K,Godornes C,Molini BJ,Van Voorhis WC,Lukehart SAdoi
10.1111/j.1365-2958.2004.04086.xsubject
Has Abstractpub_date
2004-06-01 00:00:00pages
1579-96issue
6eissn
0950-382Xissn
1365-2958pii
MMI4086journal_volume
52pub_type
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