@article {96414, title = {Endosymbiotic bacteria of the boar louse Haematopinus apri (Insecta: Phthiraptera: Anoplura)}, journal = {Frontiers in Microbiology}, volume = {13}, year = {2022}, month = {Aug-08-2022}, pages = {11 pp}, type = {Part of a research topic}, abstract = {

Insects exclusively feeding on vertebrate blood are usually dependent on symbiotic bacteria for provisioning of B vitamins. Among them, sucking lice are prominent in that their symbiotic bacteria as well as their symbiotic organs exhibit striking diversity. Here we investigated the bacterial diversity associated with the boar louse Haematopinus apri in comparison with the hog louse Haematopinus suis. Amplicon sequencing analysis identified the primary endosymbiont predominantly detected from all populations of H. apri with some minor secondary bacterial associates. Sequencing and phylogenetic analysis of bacterial 16S rRNA gene confirmed that the endosymbionts of the boar louse H. apri, the hog louse H. suis and the cattle louse Haematopinus eurysternus form a distinct clade in the Gammaproteobacteria. The endosymbiont clade of Haematopinus spp. was phylogenetically distinct from the primary endosymbionts of other louse lineages. Fluorescence in situ hybridization visualized the endosymbiont localization within midgut epithelium, ovarial ampulla and posterior oocyte of H. apri, which were substantially the same as the endosymbiont localization previously described in H. suis and H. eurysternus. Mitochondrial haplotype analysis revealed that, although the domestic pig was derived from the wild boar over the past 8,000 years of human history, the populations of H. apri constituted a distinct sister clade to the populations of H. suis. Based on these results, we discussed possible evolutionary trajectories of the boar louse, the hog louse and their endosymbionts in the context of swine domestication. We proposed \‘Candidatus Haematopinicola symbiotica\’ for the distinct clade of the endosymbionts of Haematopinus spp.

}, issn = {1664-302X}, doi = {10.3389/fmicb.2022.962252}, url = {https://www.frontiersin.org/articles/10.3389/fmicb.2022.962252/full}, author = {Yudai Nishide and Kohei Oguchi and Maria Murakami and Minoru Moriyama and Koga,Ryuichi and Fukatsu,Takema} } @article {94338, title = {Two Bacterial Genera, Sodalis and Rickettsia, Associated with the Seal Louse Proechinophthirus fluctus (Phthiraptera: Anoplura)}, journal = {Applied and Environmental Microbiology}, volume = {82}, year = {2016}, month = {June 2016}, pages = {3185 - 3197}, abstract = {

Roughly 10\% to 15\% of insect species host heritable symbiotic bacteria known as endosymbionts. The lice parasitizing mammals rely on endosymbionts to provide essential vitamins absent in their blood meals. Here, we describe two bacterial associates from a louse, Proechinophthirus fluctus, which is an obligate ectoparasite of a marine mammal. One of these is a heritable endosymbi- ont that is not closely related to endosymbionts of other mammalian lice. Rather, it is more closely related to endosymbionts of the genus Sodalis associated with spittlebugs and feather-chewing bird lice. Localization and vertical transmission of this endo- symbiont are also more similar to those of bird lice than to those of other mammalian lice. The endosymbiont genome appears to be degrading in symbiosis; however, it is considerably larger than the genomes of other mammalian louse endosymbionts. These patterns suggest the possibility that this Sodalis endosymbiont might be recently acquired, replacing a now-extinct, an- cient endosymbiont. From the same lice, we also identified an abundant bacterium belonging to the genus Rickettsia that is closely related to Rickettsia ricketsii, a human pathogen vectored by ticks. No obvious masses of the Rickettsia bacterium were observed in louse tissues, nor did we find any evidence of vertical transmission, so the nature of its association remains unclear.

}, keywords = {endosymbionts, Rickettsia, seal, Sodalis, symbiotic bacteria}, issn = {0099-2240}, doi = {10.1128/AEM.00282-16}, url = {http://aem.asm.org/lookup/doi/10.1128/AEM.00282-16https://syndication.highwire.org/content/doi/10.1128/AEM.00282-16}, author = {Boyd, Bret M. and Julie M. Allen and Koga,Ryuichi and Fukatsu,Takema and Andrew D. Sweet and Kevin P. Johnson and David L. Reed}, editor = {H. Goodrich-Blair} } @article {48295, title = {Bacterial Endosymbiont of the Slender Pigeon Louse, Columbicola columbae, Allied to Endosymbionts of Grain Weevils and Tsetse Flies}, journal = {Applied and Environmental Microbiology}, volume = {73}, year = {2007}, month = {2007}, pages = {6660 - 6668}, abstract = {

The current study focuses on a symbiotic bacterium found in the slender pigeon louse, Columbicola columbae (Insecta: Phthiraptera). Molecular phylogenetic analyses indicated that the symbiont belongs to the gamma subdivision of the class Proteobacteria and is allied to Sodalis glossinidius, the secondary symbiont of tsetse flies (Glossina spp.) and also to the primary symbiont of grain weevils (Sitophilus spp.). Relative-rate tests revealed that the symbiont of C. columbae exhibits accelerated molecular evolution in comparison with the tsetse fly symbiont and the weevil symbiont. Whole-mount in situ hybridization was used to localize the symbiont and determine infection dynamics during host development. In first- and second-instar nymphs, the symbionts were localized in the cytoplasm of oval bacteriocytes that formed small aggregates on both sides of the body cavity. In third-instar nymphs, the bacteriocytes migrated to the central body and were finally located in the anterior region of the lateral oviducts, forming conspicuous tissue formations called ovarial ampullae. In adult females, the symbionts were transmitted from the ovarial ampullae to developing oocytes in the ovarioles. In adultmales, the bacteriocytes often disappeared without migration. A diagnostic PCR survey of insects collected from Japan, the United States, Australia, and Argentina detected 96.5\% (109/113) infection, with a few uninfected male insects. This study provides the first microbial characterization of a bacteriocyte-associated symbiont from a chewing louse. Possible biological roles of the symbiont are discussed in relation to the host nutritional physiology associated with the feather-feeding lifestyle.

}, url = {http://www.phthiraptera.info/sites/phthiraptera.info/files/47438.pdf}, author = {Fukatsu,Takema and Koga,Ryuichi and Smith,Wendy A. and Tanaka,Kohjiiro and Nikoh,Naruo and Sasakki-Fukatsu,Kayoko and Kazunori Yoshizawa and Dale,Colin and Clayton,Dale H.} } @article {47838, title = {Symbiotic bacteria associated with stomach disc of human lice}, journal = {Applied and Environmental Microbiology}, volume = {72}, year = {2006}, note = {accepted manuscript}, month = {2006}, pages = {7349 - 7352}, abstract = {

The symbiotic bacteria associated with stomach disc, a large aggregate of bacteriocytes on the ventral side of midgut, of the human body and head lice were characterized. Molecular phylogenetic analysis of 16S rRNA gene sequences showed that the symbionts formed a distinct and well-defined clade in the \γ-Proteobacteria. The sequences exhibited AT-biased nucleotide composition and accelerated molecular evolution. In situ hybridization revealed that in nymphs and adult males the symbiont was localized in the stomach disc, while in adult females the symbiont was not in the stomach disc but in the lateral oviducts and the posterior pole of the oocytes due to female-specific symbiont migration. We propose the designation \“Candidatus Riesia pediculicola\” for the lice symbionts.

}, keywords = {Anoplura, bacteriocytes}, doi = {10.1128/AEM.01429-06}, url = {http://pubmedcentralcanada.ca/pmcc/articles/PMC1636134/pdf/1429-06.pdf}, author = {Sasaki-Fukatsu,Kayoko and Koga,Ryuichi and Nikoh,Naruo and Kazunori Yoshizawa and Kasai,Shinji and Minoru,Mihara and Kobayashi,Matsuo and Tomita,Takashi and Fukatsu,Takema} }