4% (56/68) 55.6% (5/9) p = 0.03   15 11.8% (8/68) 11.1% (1/9)     8-12 5.9% (4/68) selleck inhibitor 33.3% (3/9) p = 0.003 tpr E, G, J tpr E, G, J pattern after Mse I digest           Swabs WB samples     d 91.2% (62/68) 30.8% (4/13) p < 0.001   e 1.5% (1/68) 46.2% (6/13) p < 0.001   b, p, k, j 7.4% (5/68) 23.1% (3/13)   Samples isolated in the work of Flasarová et al. [17] augmented by samples collected in 2011 in the Czech Republic were analyzed. Results show both paired and unpaired samples. wt, wildtype. Discussion Molecular detection of treponemal

DNA and the subsequent molecular typing of T. pallidum strains have allowed epidemiological mapping of treponemal syphilis strains [15]. In recent years, there has been increasing evidence showing differences in molecular genetic markers among virulent treponemal strains isolated in different countries [14, 16–34]. Some studies have shown that predominant buy Smoothened Agonist treponemal strains in a particular population can change over time [14, 17]. The selection of suitable genetic loci appears to be of enormous importance. Genetic loci suitable for molecular typing should contain a relatively high degree of variability and relatively high stability in future generations of the microbial population. Several genetic loci including tprK, tprC and the intergenic region between TP0126-TP0127

have been tested for their suitability for molecular typing and rejected because of multiallelic sequences [12] SPTLC1 or because of a lack of discriminatory power [14]. The most widely used molecular typing system [15] and its improved versions [14, 16] are in principle based on detection of genetic variability in the arp and tpr genes. As shown by Liu et al. [35], the repeat motifs in the arp gene code for

highly immunogenic protein sequences and represent a this website potential fibronectin-binding domain. The arp gene in T. pallidum strains is subject to positive selection and the size variation in repeat motifs in T. pallidum strains is likely connected with mechanisms that treponemes use to escape/evade the host’s immune response, which has been primed against the standard (and the most prevalent repeat number among clinical samples) 14-repeat variant [36]. Genes tprE, G and J are potential virulence factors and belong to tpr subfamily II [37]. These genes are expressed during syphilis infection [38, 39] and the TprEJ proteins are likely located on the outer membrane [40, 41]. Recently, Giacani et al. [40] demonstrated how the number of poly-G repeats effected transcription of tprE, G, and J through a phase variation mechanism, and the modulating effect of the TP0262 gene on the level of transcription of these tpr genes [42]. We have shown that these loci are often variable in samples taken from the same patient.