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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Genotypic Characterization of Rickettsia bellii Reveals Distinct Lineages in the United States and South America

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Krawczak, Felipe S. [1] ; Labruna, Marcelo B. [1] ; Hecht, Joy A. [2] ; Paddock, Christopher D. [2] ; Karpathy, Sandor E. [2]
Total Authors: 5
[1] Univ Sao Paulo, Fac Vet Med, Dept Prevent Vet Med & Anim Hlth, Sao Paulo, SP - Brazil
[2] Ctr Dis Control & Prevent, Rickettsial Zoonoses Branch, Natl Ctr Emerging & Zoonot Infect Dis, Atlanta, GA 30329 - USA
Total Affiliations: 2
Document type: Journal article
Web of Science Citations: 7

The bacterium Rickettsia bellii belongs to a basal group of rickettsiae that diverged prior to the pathogenic spotted fever group and typhus group Rickettsia species. Despite a diverse representation of R. bellii across more than 25 species of hard and soft ticks in the American continent, phylogeographical relationships among strains of this basal group-Rickettsia species are unknown; the work described here explores these relationships. DNA was extracted from 30 R. bellii tick isolates: 15 from the United States, 14 from Brazil, and 1 from Argentina. A total of 2,269 aligned nucleotide sites of 3 protein coding genes (gltA, atpA, and coxA) and 2 intergenic regions (rpmE-tRNA(fmet) and RC1027-xthA2) were concatenated and subjected to phylogenetic analysis by Bayesian methods. Results showed a separation of almost all isolates between North and South Americas, suggesting that they have radiated within their respective continents. Phylogenetic positions of the 30 isolates could be a result of not only their geographical origin but also the tick hosts they have coevolved with. Whether R. bellii originated with ticks in North or South America remains obscure, as our analyses did not show evidence for greater genetic divergence of R. bellii in either continent. (AU)

FAPESP's process: 15/10060-6 - Molecular characterization and multigenic phylogeography of isolates of Rickettsia bellii in the Americas
Grantee:Felipe da Silva Krawczak
Support type: Scholarships abroad - Research Internship - Doctorate