Browsing by Author "Fingerle, V."
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- Core genome phylogenetic analysis of the avian associated Borrelia turdi indicates a close relationship to Borrelia gariniiPublication . Margos, G.; Becker, N.S.; Fingerle, V.; Sing, A.; Ramos, J.A.; Lopes de Carvalho, I.; Norte, A.C.Borrelia burgdorferi sensu lato comprises a species complex of tick-transmitted bacteria that includes the agents of human Lyme borreliosis. Borrelia turdi is a genospecies of this complex that exists in cryptic transmission cycles mainly between ornithophilic tick vectors and their avian hosts. The species has been originally discovered in avian transmission cycles in Asia but has increasingly been found in Europe. Next generation sequencing was used to sequence the genome of B. turdi isolates obtained from ticks feeding on birds in Portugal to better understand the evolution and phylogenetic relationship of this avian and ornithophilic tick-associated genospecies. Here we use draft genomes of these B. turdi isolates for comparative analysis and to determine the taxonomic position within the B. burgdorferi s.l. species complex. The main chromosomes showed a maximum similarity of 93% to other Borrelia species whilst most plasmids had lower similarities. All three isolates had nine or 10 plasmids and, interestingly, one plasmid with a novel partitioning protein; this plasmid was termed lp30. Phylogenetic analysis of multilocus sequence typing housekeeping genes and 113 single copy orthologous genes revealed that the isolates clustered according to their classification as B. turdi. In phylogenies generated from these 113 genes the isolates cluster together with other Eurasian genospecies and form a sister clade to the avian associated B. garinii and the rodent associated B. bavariensis. These findings show that Borrelia species maintained in cryptic ecological cycles need to be included to fully understand the complex ecology and evolutionary history of this bacterial species complex.
- Host dispersal shapes the population structure of a tick-borne bacterial pathogenPublication . Norte, A.C.; Margos, G.; Becker, N.S.; Albino Ramos, J.; Núncio, M.S.; Fingerle, V.; Araújo, P.M.; Adamík, P.; Alivizatos, H.; Barba, E.; Barrientos, R.; Cauchard, L; Csörgő, T.; Diakou, A.; Dingemanse, N.J.; Doligez, B.; Dubiec, A.; Eeva, T.; Flaisz, B.; Grim, T.; Hau, M.; Hornok, S.; Kazantzidis, S.; Kováts, D.; Krause, F.; Literak, I.; Mänd, R.; Mentesana, L.; Morinay, J.; Mutanen, M.; Neto, J.M.; Nováková, M.; Sanz, J.J.; Pascoal da Silva, L.; Sprong, H.; Tirri, I.S.; Török, J.; Trilar, T.; Tyller, Z.; Visser, M.E.; Lopes de Carvalho, I.f ticks and their associated pathogens. The life cycle of tick-borne pathogens is complex and their evolutionary ecology is shaped by the interactions with vertebrate hosts and tick vectors (Kurtenbach et al., 2006). This study focused on the ecology and genetic diversity of B. burgdorferi s.l. as a model to investigate the drivers of the population structure and to understand the role of host- associated dispersal on the evolution of tick-borne pathogens. This represents a consequential question in the ecology and evolution of any pathogen. Borrelia burgdorferi s.l. is a bacterial complex of over 20 known genospecies, including the etiologic agents of Lyme borreliosis (Casjens et al., 2011; Margos et al., 2015), whose main vectors are ticks of the genus Ixodes (Eisen & Lane, 2002). These bacteria are widespread in Europe, Asia and North America and are also present in North Africa (Margos, Vollmer, Ogden, & Fish, 2011; Zhioua et al., 1999). Different Borrelia genospecies have different patterns of association with vertebrate reservoir hosts (Humair & Gern, 2000; Kurtenbach, Peacey, et al., 1998) because of the immunological host response, mediated by the action of the host's complement system (Kurtenbach et al., 2002). While B. burgdorferi sensu stricto (s.s.) is a generalist genospecies, Borrelia afzelii is mostly associated with mammalian hosts such as rodents, whereas Borrelia valaisiana, Borrelia garinii and Borrelia turdi are mostly associated with birds (Heylen, 2016; Margos et al., 2011). Because tick vectors cannot move large distances independent of hosts, it has been suggested that host specialization determines the spread and dispersal of B. burgdorferi s.l. genospecies (Kurtenbach et al., 2010; Sonenshine & Mather, 1994). Because birds are both important hosts for some Borrelia genospecies and for various species of vector ticks, they act as a driving force shaping B. burgdorferi s.l. distribution and phylogeographical patterns (Margos et al., 2011; Vollmer et al., 2011). Here, we assessed the role of passerine birds as hosts and dispersers of B. burgdorferi s.l. We tested the hypothesis that infection prevalence with Borrelia genospecie
- Host-parasite interactions between Borrelia burgdorferi s.l. and its avian reservoir hostsPublication . Norte, A.C.; Heylen, D.; Margos, G.; Fingerle, V.; Becker, N.; Araújo, P.M.; da Silva, L.P.; Sprong, H.; Krawczyk, A.; Costantini, D.; Eens, M.; Núncio, M.S.; Ramos, J.A.; Lopes de Carvalho, I.Borrelia burgdorferi sensu lato (s.l.) is maintained in enzootic cycles in nature by vertebrate reservoir hosts, including mammals, lizards and birds. To understand the eco-epidemiology of Lyme borreliosis it is necessary to evaluate the relationships among Borrelia genospecies, their tick vectors and vertebrate reservoir hosts. We surveyed infection prevalence in avian hosts and using wild birds as models, we performed transmission experiments, assessed the physiological impact of infection in reservoir hosts and how exposure to stress could affect the host’s infectivity to vector ticks. Additionally, we evaluated the population structure of an avian-associated Borrelia genospecies.
- Pandora's flying box - Borrelia burgdorferi sensu lato prevalence in Ixodes species from birds throughout EuropePublication . Norte, A. C.; Ramos, J.A.; Núncio, M.S.; Margos, G.; Fingerle, V.; Adamik, P.; Alivizatos, H.; Barba, E.; Barrientos, R.; Cauchard, L.; Csörgo, T.; Diakou, A.; Dingemanse, N.J.; Doligez, B.; Dubiec, A.; Eeva, T.; Flaisz, B.; Grim, T.; Hau, M.; Heylen, D.; Hornok, S.; Kazantzidis, S.; Kováts, D.; Krause, F.; Literak, I.; Mänd, R.; Mentesana, L.; Morinay, J.; Mutanen, M.; Neto, J.; Nováková, M.; Sanz, J.J.; Silva, L.P.; Sprong, H.; Tirri, I.S.; Török, J.; Trilar, T.; Tyller, Z.; Visser, M.E.; Lopes de Carvalho, I.Birds are important hosts for ticks and may act as reservoirs for several zoonotic pathogens. Because of their high mobility, especially of the long distance migratory species, they can act as dispersers for ticks and pathogens, ultimately affecting their distribution and phylogeography.
- The Population Structure of Borrelia lusitaniae Is Reflected by a Population Division of Its Ixodes VectorPublication . Norte, A.C.; Boyer, P.H.; Castillo-Ramirez, S.; Chvostac, M.; Brahami, M.O.; Rollins, R.E.; Woudenberg, T.; Didyk, Y.M.; Derdakova, M.; Núncio, M.S.; Lopes de Carvalho, I.; Margos, G.; Fingerle, V.Populations of vector-borne pathogens are shaped by the distribution and movement of vector and reservoir hosts. To study what impact host and vector association have on tick-borne pathogens, we investigated the population structure of Borrelia lusitaniae using multilocus sequence typing (MLST). Novel sequences were acquired from questing ticks collected in multiple North African and European locations and were supplemented by publicly available sequences at the Borrelia Pubmlst database (accessed on 11 February 2020). Population structure of B. lusitaniae was inferred using clustering and network analyses. Maximum likelihood phylogenies for two molecular tick markers (the mitochondrial 16S rRNA locus and a nuclear locus, Tick-receptor of outer surface protein A, trospA) were used to confirm the morphological species identification of collected ticks. Our results confirmed that B. lusitaniae does indeed form two distinguishable populations: one containing mostly European samples and the other mostly Portuguese and North African samples. Of interest, Portuguese samples clustered largely based on being from north (European) or south (North African) of the river Targus. As two different Ixodes species (i.e., I. ricinus and I. inopinatus) may vector Borrelia in these regions, reference samples were included for I. inopinatus but did not form monophyletic clades in either tree, suggesting some misidentification. Even so, the trospA phylogeny showed a monophyletic clade containing tick samples from Northern Africa and Portugal southoftheriverTagussuggestingapopulationdivisioninIxodesonthislocus. Thepatternmirrored the clustering of B. lusitaniae samples, suggesting a potential co-evolution between tick and Borrelia populations that deserve further investigation.