title: Molecular screening for Midichloria in hard and soft ticks reveals variable prevalence levels and bacterial loads in different tick species.
abstract: Candidatus Midichloria mitochondrii, symbiont of the sheep tick Ixodes ricinus, was the first described member of the family Candidatus Midichloriaceae, order Rickettsiales. Recent reports are expanding our view of this family, now including numerous bacteria of great biological and medical interest, indicating a widespread distribution with an increasing range of hosts, with ticks being strongly represented. Here we present a molecular screening of 17 tick species, detecting and quantifying bacteria of the family Midichloriaceae in seven of them, including the first report of a representative of this family in a soft tick species (Argasidae), Ornithodoros maritimus. Based on sequence identity and phylogenetic analysis we propose that all these bacterial symbionts of ticks could be members of the genus Midichloria. The performed screening highlights different prevalence levels and variable bacterial loads in different tick species including one, Ixodes aulacodi, where the bacterium is present in all examined individuals, like in I. ricinus. This result prompts us to hypothesize different roles of Midichloria bacteria in different tick species.
authors: Department of Veterinary Medicine, University of Milan, Via Celoria 10, 20133 Milan, Italy.
authors: Alessandra
authors: A
authors: Cafiso
authors: Department of Veterinary Medicine, University of Milan, Via Celoria 10, 20133 Milan, Italy; Joint Research Center for Epidemiology and Molecular Surveillance of Infections, University of Milan, 20133 Milan, Italy.
authors: Chiara
authors: C
authors: Bazzocchi
authors: Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100 Pavia, Italy; School of Bioscience and Veterinary Medicine, University of Camerino, Via Gentile III Da Varano, 62032 Camerino, Italy.
authors: Leone
authors: L
authors: De Marco
authors: Department of Parasitology and Entomology, Faculty of Veterinary Medicine, University of Abuja, PMB 117, FCT Nigeria.
authors: Maxwell N
authors: MN
authors: Opara
authors: Department of Biology and Biotechnology, University of Pavia, Via Ferrata 9, 27100 Pavia, Italy. Electronic address: davide.sassera@unipv.it.
authors: Davide
authors: D
authors: Sassera
authors: BIOEPAR, INRA, Oniris, Route de Gachet, 44307 Nantes, France.
authors: Olivier
authors: O
authors: Plantard
mesh_terms: D020561:Alphaproteobacteria / Q000235:genetics / Q000302:isolation & purification; D000818:Animals; D026862:Argasidae / Q000235:genetics*; D058491:Bacterial Load; D004269:DNA, Bacterial; D026863:Ixodidae / Q000382:microbiology*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013045:Species Specificity
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S
keywords: Amblyomma; Hyalomma; Ixodes; Midichloria spp; Ornithodoros