Human Treponema pallidum 11q/j isolate belongs to subsp. endemicum but contains two loci with a sequence in TP0548 and TP0488 similar to subsp. pertenue and subsp. pallidum, respectively

• Published in: PLoS neglected tropical diseases 2017-03, Vol.11 (3), p.e0005434-e0005434
• Main Authors: Mikalová, Lenka, Strouhal, Michal, Oppelt, Jan, Grange, Philippe Alain, Janier, Michel, Benhaddou, Nadjet, Dupin, Nicolas, Šmajs, David
• Format: Article
• Language: English
• Subjects: Adult; Age; Antigens; Bacteria; Bacterial infections; Biochemistry; Biological evolution; Biology; Biology and Life Sciences; Bones; Chemotaxis; Children; Chimpanzees; Chromosome 11; Chronic infection; Classification; Cluster Analysis; Computer applications; Cross sections; Data acquisition; Data processing; Decision analysis; Deoxyribonucleic acid; Descartes; DNA; DNA sequencing; Evolution, Molecular; Evolutionary genetics; France; Gene expression; Genetic aspects; Genetic Loci; Genetic Variation; Genomes; Genotype; Grants; Health aspects; Heterogeneity; Humans; Infections; Infectious diseases; Larynx; Lesions; Loci; Male; Medicine; Medicine and Health Sciences; Membrane proteins; Microbiology; Mitochondrial DNA; Mucosa; Nasopharynx; Nucleotide sequence; Oral cavity; Pakistan; Penicillin; People and Places; Phylogeny; Polymerase Chain Reaction; Proteins; Public health; Recombination; Recombination, Genetic; Reconstruction; Research and analysis methods; Separation; Sequence Analysis, DNA; Sequence Homology; Sexually transmitted diseases; Skin diseases; STD; Syphilis; Syphilis - microbiology; Travel; Treponema pallidum; Treponema pallidum - genetics; Treponema pallidum - isolation & purification; Tropical diseases; Typing; Yaws
• ISSN: 1935-2735; 1935-2727; 1935-2735
• DOI: 10.1371/journal.pntd.0005434

Treponema pallidum subsp. endemicum (TEN) is the causative agent of endemic syphilis (bejel). An unusual human TEN 11q/j isolate was obtained from a syphilis-like primary genital lesion from a patient that returned to France from Pakistan. The TEN 11q/j isolate was characterized using nested PCR followed by Sanger sequencing and/or direct Illumina sequencing. Altogether, 44 chromosomal regions were analyzed. Overall, the 11q/j isolate clustered with TEN strains Bosnia A and Iraq B as expected from previous TEN classification of the 11q/j isolate. However, the 11q/j sequence in a 505 bp-long region at the TP0488 locus was similar to Treponema pallidum subsp. pallidum (TPA) strains, but not to TEN Bosnia A and Iraq B sequences, suggesting a recombination event at this locus. Similarly, the 11q/j sequence in a 613 bp-long region at the TP0548 locus was similar to Treponema pallidum subsp. pertenue (TPE) strains, but not to TEN sequences. A detailed analysis of two recombinant loci found in the 11q/j clinical isolate revealed that the recombination event occurred just once, in the TP0488, with the donor sequence originating from a TPA strain. Since TEN Bosnia A and Iraq B were found to contain TPA-like sequences at the TP0548 locus, the recombination at TP0548 took place in a treponeme that was an ancestor to both TEN Bosnia A and Iraq B. The sequence of 11q/j isolate in TP0548 represents an ancestral TEN sequence that is similar to yaws-causing treponemes. In addition to the importance of the 11q/j isolate for reconstruction of the TEN phylogeny, this case emphasizes the possible role of TEN strains in development of syphilis-like lesions.