Molecular phylogeny of the genus Bartonella: what is the current knowledge?

Abstract

Species of the genus Bartonella are involved in an increasing variety of human diseases. In addition to the 14 currently recognized species, several Bartonella strains have been recovered from a wide range of wild and domestic mammals in Europe and America. Such a high diversity of geographic distributions, animal reservoirs, arthropod vectors and pathogenic properties makes clarification of our knowledge about the phylogeny of Bartonella species necessary. Phylogenetic data have been inferred mainly from 16S rDNA, 16S^23S rRNA intergenic spacer, citrate synthase and 60 kDa heat-shock protein gene sequences, which are available in GenBank. Comparison of phylogenetic organizations obtained from various genes allowed six statistically significant evolutionary clusters to be identified. Bartonella bacilliformis and Bartonella clarridgeiae appear to be divergent species. Bartonella henselae, Bartonella koehlerae and Bartonella quintana cluster together, as well as Bartonella vinsonii subsp. vinsonii and B. vinsonii subsp. berkhoffii. The fifth group includes bacteria isolated from various rodents that belong to native species from the New World and in the sixth, Bartonella tribocorum, Bartonella elizabethae and Bartonella grahamii are grouped with several strains associated with Old World indigenous rodents. The position of the other species could not be consistently determined. As some cat-or rodent-associated Bartonella appeared to cluster together, it has been suggested that these bacteria and their reservoir hosts may co-evolve. Lack of host specificity, however, seems to be frequent and may reflect the influence of vector specificity. Host or vector specificity may also explain the current geographic distribution of Bartonella species. ß 2001 Published by Elsevier Science B.V. on behalf of the Federation of European Microbiological Societies.

Genetic Classification and Differentiation of Bartonella Species Based on Comparison of Partial ftsZ Gene Sequences

“…In the past decade, a number of new Bartonella species have been described (6,15,27) and comparisons of 16S rDNA sequences have led to many taxonomic changes in the genus Bartonella (7,11). Although comparison of 16S rDNA gene sequences has been useful in phylogenetic studies at the genus level (41), its use has been questioned in studies at the species level (21; M. Hasegawa and T. Hashimoto, Letter, Nature 361:23, 1993).…”

“…Recently the number of Bartonella species isolated has increased markedly (5,6,15,27), and the bacteria are considered emerging pathogens involved in an increasing number of recognized diseases (1,28,38). Currently, 19 Bartonella species are recognized, and all are associated with mammalian hosts.…”

High Prevalence of Rickettsia typhi and Bartonella Species in Rats and Fleas, Kisangani, Democratic Republic of the Congo

“…Species of the genus Bartonella are associated with an increasing array of human diseases, among which bacillary angiomatosis and peliosis hepatitis in immunocompromised patients. 13 Mammalian reservoirs of Bartonella include small carnivores and rodents, 14 their transmission rate depends on the Bartonella strain, host, and specific vector. Historical data on rickettsiosis and bartonellosis in the Democratic Republic of the Congo (DRC) (former Zaire) are fragmentary, but serological tests have reported Rickettsia conorii, Rickettsia prowazekii, and R. typhi as early as the 1950s.…”

Diversity of bartonellae associated with small mammals inhabiting Free State province, South Africa

“…The usefulness of comparative analysis of DNA sequence data to delineate Bartonella species has already been demonstrated (Lawson & Collins, 1996), and the application of this approach as the primary criterion for species definition has recently been proposed (La Scola et al, 2003). Several genetic loci have been used for the characterization of Bartonella isolates (Houpikian & Raoult, 2001), but comparative analysis of citrate synthase gene (gltA) fragments remains the most commonly used approach for identifying bartonellae and inferring evolutionary relationships within the genus (Birtles & Raoult, 1996). Studies of inferred evolutionary relationships among Bartonella species have revealed that species parasitizing the same or similar host species are not necessarily closely related.…”