title: A House for Two--Double Bacterial Infection in Euplotes woodruffi Sq1 (Ciliophora, Euplotia) Sampled in Southeastern Brazil.
abstract: Several ciliated protists form symbiotic associations with a diversity of microorganisms, leading to drastic impact on their ecology and evolution. In this work, two Euplotes spp. sampled in Rio de Janeiro, Brazil, were identified based on morphological and molecular features as Euplotes woodruffi strain Sq1 and E. encysticus strain Sq2 and investigated for the presence of endosymbionts. While E. woodruffi Sq1 stably hosts two bacterial populations, namely Polynucleobacter necessarius (Betaproteobacteria) and a new member of the family "Candidatus Midichloriaceae" (Alphaproteobacteria, Rickettsiales), here described as "Candidatus Bandiella woodruffii," branching with a broad host range bacterial group found in association with cnidarians, sponges, euglenoids, and some arthropods; in E. encysticus Sq2 no symbiotic bacterium could be detected. The dispersion ability of this novel bacterium was tested by co-incubating E. woodruffi Sq1 with three different ciliate species. Among the tested strains "Ca. B. woodruffii" could only be detected in association with E. encysticus Sq2 with a prevalence of 20 % after 1 week and 40 % after 2 weeks, maintaining this level for up to 6 months. Nevertheless, this apparent in vitro association was abolished when E. woodruffi Sq1 donor was removed from the microcosm, suggesting that this bacterium has the capacity for at least a short-term survival outside its natural host and the aptitude to ephemerally interact with other organisms. Together, these findings strongly suggest the need for more detailed investigations to evaluate the host range for "Ca. B. woodruffii" and any possible pathogenic effect of this bacterium on other organisms including humans.
authors.affiliation: Departamento de Genética, Universidade Federal do Rio de Janeiro, UFRJ, Av. Carlos Chagas Filho 373 - CCS A2-120, Rio de Janeiro, 21.944-970, Brazil.|Departamento de Zoologia, Universidade Federal de Juiz de Fora, UFJF, Rio de Janeiro, Brazil.
authors.forename: Marcus V X
authors.initials: MV
authors.lastname: Senra
authors.affiliation: Departamento de Zoologia, Universidade Federal do Rio de Janeiro, UFRJ, Rio de Janeiro, Brazil.|Departamento de Zoologia, Universidade Federal de Juiz de Fora, UFJF, Rio de Janeiro, Brazil.
authors.forename: Roberto J P
authors.initials: RJ
authors.lastname: Dias
authors.affiliation: Department of Biology, University of Pisa, via A. Volta 4/6, Pisa, 56126, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Castelli
authors.affiliation: Departamento de Zoologia, Universidade Federal do Rio de Janeiro, UFRJ, Rio de Janeiro, Brazil.
authors.forename: Inácio D
authors.initials: ID
authors.lastname: Silva-Neto
authors.affiliation: Department of Biology, University of Pisa, via A. Volta 4/6, Pisa, 56126, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Verni
authors.affiliation: Departamento de Genética, Universidade Federal do Rio de Janeiro, UFRJ, Av. Carlos Chagas Filho 373 - CCS A2-120, Rio de Janeiro, 21.944-970, Brazil. soares@biologia.ufrj.br.
authors.forename: Carlos A G
authors.initials: CA
authors.lastname: Soares
authors.affiliation: Department of Biology, University of Pisa, via A. Volta 4/6, Pisa, 56126, Italy. giulio.petroni@unipi.it.
authors.forename: Giulio
authors.initials: G
authors.lastname: Petroni
mesh_terms: D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D018407:Bacterial Physiological Phenomena; D001938:Brazil; D016812:Euplotes / Q000145:classification / Q000382:microbiology* / Q000502:physiology; D058507:Host Specificity; D008969:Molecular Sequence Data; D010802:Phylogeny; D013559:Symbiosis
keywords: Bacterial symbionts; Ciliates; Molecular phylogeny; Symbiont dispersion