Genetic and Phenotypic Analysis of Borrelia valaisiana sp. nov. (Borrelia Genomic Groups VS116 and M19)

Abstract

To clarify the taxonomic status of two recently described Borrelia genomic groups, groups VS116 and M19, three group VS116 strains and eight group M19 strains isolated from Ixodes ricinus ticks in Switzerland, The Netherlands, and the United Kingdom were characterized. PCR-restriction fragment length polymorphism (RFLP) analysis of the 5s-23s intergenic spacer amplicon, rRNA gene restriction analysis, 16s rRNA gene sequence analysis, randomly amplified polymorphic DNA (RAPD) fingerprinting, sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE), and immunoblotting with monoclonal antibodies were used for genetic and phenotypic analysis. The PCR-RFLP and RAPD patterns of three group VS116 strains and eight group M19 strains were identical but differed from those of Borrelia burgdorferi sensu stricto, Borrelia garinii, Borrelia afielii, and Borrelia japonica. DNAs from all group VS116 and M19 strains yielded three fragments (6.9, 3.2, and 1.4 kb) and four fragments (2.1, 1.2, 0.8, and 0.6 kb) after digestion with EcoRV and HindIII, respectively, hybridizing with an Escherichia coli 16s +23S cDNA probe. The SDS-PAGE protein profiles of group VS116 and M19 strains were heterogeneous. Phylogenetic analysis of the partial 16s rRNA gene sequences showed that group VS116 and M19 spirochetes were members of a Borrelia species distinct from previously characterized members of the genus Borrelia. Based on our present study and data from previous DNA-DNA hybridizations, a new Borrelia species, Borrelia valaisiana sp. nov., in the B. burgdorferi complex, is proposed. Strain VS116 is the type strain of this new species.

Infection of Ixodes ricinus (Acari: Ixodidae) by Borrelia burgdorferi sensu lato in North Africa

“…These genospecies have been isolated from patients, rodents, birds, and I. ricinus from various areas in Europe (Humair et al 1995, Olsen et al 1995, Picken et al 1996, Zhioua et al 1996. Two additional genospecies have been observed in I. ricinus and identiÞed as B. valaisiana and B. lusitaniae (formerly the genospecies VS116 and PotiB2, respectively) (Postic et al 1994Pé ter et al 1995;Rijpkema et al 1995;Le Flè che et al 1997;Wang et al 1997). To date, only a few isolates have been identiÞed as B. lusitaniae; 3 from Portugal, 2 from Moldavia, 1 from Ukraine, 1 from Czech Republic (Postic et al 1994, and now 1 from North Africa.…”

“…Borrelia burgdorferi sensu lato is now known to include at least 5 genospecies associated with I. ricinus: Borrelia burgdorferi sensu stricto, Borrelia garinii, Borrelia afzelii, Borrelia valaisiana (formerly genospecies VS116), and Borrelia lusitaniae (formerly genospecies PotiB2) (Baranton et al 1992;Canica et al 1993;Postic et al 1994Postic et al , 1997Le Flè che et al 1997;Wang et al 1997). The geographical distribution of I. ricinus covers southern Scandinavia, the British Isles, Central Europe, France, Spain, Portugal, Italy, the Balkans, East Europe, northern Iran, and North Africa Rodhain 1977, Stanek et al 1988).…”

Borrelioses, agentes e vetores

“…No ano seguinte Barbour et al (1996) descreveram uma borrélia, inicialmente considerada não-cultivável, isolada do carrapato Amblyomma americanum; essa bactéria foi denominada B. lonestari, com posição filogenética próxima à B. burgdorferi. Em 1997, foi descrita na Europa B. lusitaniae (Le ) e a B. valaisiana (Wang et al 1997), todas agentes do "complexo borreliose de Lyme".…”

“…A doença de Lyme tem como agentes B. burgdorferi, em vários continentes, B. garinii (Baranton et al 1992) na Europa, B. afzelii (Canica et al 1993) na Europa e no Japão, B. japonica (Kawabata et al 1993) no Japão, B. miyamotoi na Ásia , B. andersoni (Marconi et al 1995) e B. lonestari (Barbour et al 1996) na América do Norte, B. lusitaniae ) na Europa, B. valaisiana (Wang et al 1997) na Europa e a genoespécie denominada DN 127 nos Estados Unidos da América. Esses agentes e suas variantes antigênicas são responsáveis pelas diversas apresentações clínicas da enfermidade (Bennett 1995, Silva & Fikrig 1997.…”

“…(3) Espiroquetose bovina, causada por B. theileri Laveran, 1903, determina anemia em ruminantes e eqüinos, considerada pouco patogê-nica (Koch et al 1990, Quinn et al 1994. (4) Borreliose de Lyme, causada pelo grupo B. burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner, 1984 "lato sensu", com nove espécies definidas e uma genoespécie não nomeada (Quadro 1) (Bennett 1995, Euzeby 1995, Marconi et al 1995, Barbour et al 1996, Wang et al 1997. (5) Aborto epizoótico bovino, enfermidade que acomete bovinos e cerví-deos, determinada por B. coriaceae Johnson, Burgdorfer, Lane, Barbour, Hayes & Hyde, 1987(Breitschwerdt et al 1994, Zingg & Lefebvre 1994.…”