OspA heterogeneity of Borrelia valaisianaconfirmed by phenotypic and genotypic analyses

Abstract

Background: Although European Borrelia burgdorferi sensu lato isolates have been divided into five genospecies, specific tools for the serotype characterization of only three genospecies are available. Monoclonals antibodies (mAbs) H3TS, D6 and I17.3 identify B. burgdorferi sensu stricto (ss.), B. garinii and B. afzelii respectively, but no mAbs are available to identify B. valaisiana. In the same way, specific primers exist to amplify the OspA gene of B. burgdorferi ss., B. garinii and B. afzelii. The aim of the study was to develop species-specific mAb and PCR primers for the phenotypic and genetic identification of B. valaisiana.

Characterization of Borrelia lusitaniae Isolates Collected in Tunisia and Morocco

“…The relative level of conservation of ospA sequences from B. lusitaniae could be attributed to the restricted geographic extension and to the interaction with only one vector species and possibly one predominant reservoir host. This fact contrasts with the diversity reported for B. valaisiana, which is more widely distributed and is associated with several tick species, requiring adaptation to a broad range of vectors (12,22,24,32,40). Our analysis of the restriction polymorphism of the small rrf-rrl spacer emphasized a high monomorphism that was confirmed by the conservation of sequences within B. lusitaniae isolates from North Africa.…”

“…The genetic diversity of pathogenic species has been largely investigated both at the species level and at the strain level within each species (41). Otherwise, although its pathogenicity for humans is only suspected (31, 33), Borrelia valaisiana represents a widely distributed species in ticks throughout Europe and Asia and therefore has been extensively studied (12,22,32,38,40).In contrast to these species, little data are available concerning Borrelia lusitaniae. Only sporadic isolates have been characterized from ticks collected in the Czech Republic, Moldavia, Ukraine, and Belarus (20), in Slovakia (11), in Spain (3), in Poland (25), in France (30), in Switzerland (15-17), or in Turkey (13), and these isolates did not show any significant diversity.…”

“…The genetic diversity of pathogenic species has been largely investigated both at the species level and at the strain level within each species (41). Otherwise, although its pathogenicity for humans is only suspected (31,33), Borrelia valaisiana represents a widely distributed species in ticks throughout Europe and Asia and therefore has been extensively studied (12,22,32,38,40).…”

Lyme Borreliosis Spirochetes and Spotted Fever Group Rickettsiae in Ixodid Ticks from Pianosa Island, Tuscany Archipelago, Italy

“…The dendrogram based on the ospA gene (Fig. 2) showed that the B. valaisiana sequences belong to the subgroup I strain (Wang et al 2000;Ryffel et al 2003); the pairwise genetic distances varied from 0 to 0.023. Only one ospA B. spielmanii sequence was obtained.…”