title: Prevalence of Cardinium bacteria in planthoppers and spider mites and taxonomic revision of "Candidatus Cardinium hertigii" based on detection of a new Cardinium group from biting midges.
abstract: Cardinium bacteria, members of the phylum Cytophaga-Flavobacterium-Bacteroides (CFB), are intracellular bacteria in arthropods that are capable of inducing reproductive abnormalities in their hosts, which include parasitic wasps, mites, and spiders. A high frequency of Cardinium infection was detected in planthoppers (27 out of 57 species were infected). A high frequency of Cardinium infection was also found in spider mites (9 out of 22 species were infected). Frequencies of double infection by Cardinium and Wolbachia bacteria (Alphaproteobacteria capable of manipulating reproduction of their hosts) were disproportionately high in planthoppers but not in spider mites. A new group of bacteria, phylogenetically closely related to but distinct from previously described Cardinium bacteria (based on 16S rRNA and gyrB genes) was found in 4 out of 25 species of Culicoides biting midges. These bacteria possessed a microfilament-like structure that is a morphological feature previously found in Cardinium and Paenicardinium. The bacteria close to the genus Cardinium consist of at least three groups, A, B, and C. Group A is present in various species of arthropods and was previously referred to as "Candidatus Cardinium hertigii," group B is present in plant parasitic nematodes and was previously referred to as "Candidatus Paenicardinium endonii," and group C is present in Culicoides biting midges. On the basis of morphological and molecular data, we propose that the nomenclature of these three groups be integrated into a single species, "Candidatus Cardinium hertigii."
authors.affiliation: National Institute of Agrobiological Sciences, Owashi, Tsukuba, Ibaraki 305-8634, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Sawako
authors.initials: S
authors.lastname: Kawai
authors.forename: Fumiko
authors.initials: F
authors.lastname: Yukuhiro
authors.forename: Saiko
authors.initials: S
authors.lastname: Ito
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Gotoh
authors.forename: Ryoiti
authors.initials: R
authors.lastname: Kisimoto
authors.forename: Tohru
authors.initials: T
authors.lastname: Yanase
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Matsumoto
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kageyama
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Noda
mesh_terms: D000818:Animals; D001181:Arthropods / Q000382:microbiology*; D001424:Bacterial Infections / Q000382:microbiology / Q000662:veterinary*; D041963:Bacteroidetes / Q000145:classification* / Q000302:isolation & purification*; D016000:Cluster Analysis; D027081:DNA Gyrase / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D010802:Phylogeny; D015995:Prevalence; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D027081:DNA Gyrase