The apicomplexans are a group of obligate animal pathogens that include Plasmodium (malaria), Toxoplasma (toxoplasmosis), and Cryptosporidium (cryptosporidiosis) [1]. They are an extremely diverse and specious group but are nevertheless united by a distinctive suite of cytoskeletal and secretory structures related to infection, called the apical complex, which is used to recognize and gain entry into animal host cells. The apicomplexans are also known to have evolved from free-living photosynthetic ancestors and retain a relict plastid (the apicoplast), which is non-photosynthetic but houses a number of other essential metabolic pathways [2]. Their closest relatives include a mix of both photosynthetic algae (chromerids) and non-photosynthetic microbial predators (colpodellids) [3]. Genomic analyses of these free-living relatives have revealed a great deal about how the alga-parasite transition may have taken place, as well as origins of parasitism more generally [4]. Here, we show that, despite the surprisingly complex origin of apicomplexans from algae, this transition actually occurred at least three times independently. Using single-cell genomics and transcriptomics from diverse uncultivated parasites, we find that two genera previously classified within the Apicomplexa, Piridium and Platyproteum, form separately branching lineages in phylogenomic analyses. Both retain cryptic plastids with genomic and metabolic features convergent with apicomplexans. These findings suggest a predilection in this lineage for both the convergent loss of photosynthesis and transition to parasitism, resulting in multiple lineages of superficially similar animal parasites.

• MeSH
• Apicomplexa klasifikace   MeSH
• apikoplasty klasifikace   MeSH
• biologická evoluce * MeSH
• fylogeneze MeSH
• paraziti klasifikace   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Members of the genus Trichonympha are among the most well-known, recognizable and widely distributed parabasalian symbionts of lower termites and the wood-eating cockroach species of the genus Cryptocercus. Nevertheless, the species diversity of this genus is largely unknown. Molecular data have shown that the superficial morphological similarities traditionally used to identify species are inadequate, and have challenged the view that the same species of the genus Trichonympha can occur in many different host species. Ambiguities in the literature, uncertainty in identification of both symbiont and host, and incomplete samplings are limiting our understanding of the systematics, ecology and evolution of this taxon. Here we describe four closely related novel species of the genus Trichonympha collected from South American and Australian lower termites: Trichonympha hueyi sp. nov. from Rugitermes laticollis, Trichonympha deweyi sp. nov. from Glyptotermes brevicornis, Trichonympha louiei sp. nov. from Calcaritermes temnocephalus and Trichonympha webbyae sp. nov. from Rugitermes bicolor. We provide molecular barcodes to identify both the symbionts and their hosts, and infer the phylogeny of the genus Trichonympha based on small subunit rRNA gene sequences. The analysis confirms the considerable divergence of symbionts of members of the genus Cryptocercus, and shows that the two clades of the genus Trichonympha harboured by termites reflect only in part the phylogeny of their hosts.

• MeSH
• fylogeneze * MeSH
• Hypermastigia klasifikace   genetika   izolace a purifikace   MeSH
• Isoptera mikrobiologie   MeSH
• RNA protozoální genetika   MeSH
• RNA ribozomální genetika   MeSH
• sekvenční analýza DNA MeSH
• symbióza MeSH
• trávicí systém mikrobiologie   MeSH
• zastoupení bazí MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Austrálie MeSH
• Ekvádor MeSH
• Peru MeSH

Pseudotrichonympha is a large and structurally complex genus of parabasalian protists that play a key role in the digestion of lignocellulose in the termite hindgut. Like many termite symbionts, it has a conspicuous body plan that makes genus-level identification relatively easy, but species-level diversity of Pseudotrichonympha is understudied. Molecular surveys have suggested the diversity is much greater than the current number of described species, and that many "species" described in multiple hosts are in fact different, but gene sequences from formally described species remain a rarity. Here we describe three new species from Coptotermes and Prorhinotermes hosts, including small subunit ribosomal RNA (SSU rRNA) sequences from single cells. Based on host identification by morphology and DNA barcoding, as well as the morphology and phylogenetic position of each symbiont, all three represent new Pseudotrichonympha species: P. leei, P. lifesoni, and P. pearti. Pseudotrichonympha leei and P. lifesoni, both from Coptotermes, are closely related to other Coptotermes symbionts including the type species, P. hertwigi. Pseudotrichonympha pearti is the outlier of the trio, more distantly related to P. leei and P. lifesoni than they are to one another, and contains unique features, including an unusual rotating intracellular structure of unknown function.

• MeSH
• fylogeneze MeSH
• Isoptera parazitologie   MeSH
• mikroskopie MeSH
• Parabasalidea klasifikace   cytologie   fyziologie   MeSH
• protozoální geny MeSH
• RNA ribozomální genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• muskuloskeletální nemoci terapie   MeSH
• ortopedické výkony MeSH
• sportovní úrazy terapie   MeSH

• Konspekt
• Ortopedie. Chirurgie. Oftalmologie
• NLK Obory
• ortopedie
• tělovýchovné lékařství
• NLK Publikační typ
• kolektivní monografie

• Klíčová slova
• Biologie molekulární, Proteiny,
• MeSH
• molekulární biologie MeSH
• proteiny MeSH

• MeSH
• psychoneuroimunologie MeSH
• Publikační typ
• monografie MeSH

• Konspekt
• Psychiatrie
• NLK Obory
• behaviorální vědy

• MeSH
• hematologie MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• hematologie a transfuzní lékařství
• NLK Publikační typ
• kolektivní monografie

• MeSH
• antiinfekční látky MeSH
• mikrobiologické jevy MeSH
• sterilizace MeSH

• Konspekt
• Veřejné zdraví a hygiena
• NLK Obory
• hygiena
• NLK Publikační typ
• kolektivní monografie

• MeSH
• alergie * MeSH
• alergologie a imunologie MeSH
• imunita MeSH
• Publikační typ
• monografie MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• alergologie a imunologie

• MeSH
• hematologie MeSH
• krevní nemoci diagnóza   terapie   MeSH
• Publikační typ
• monografie MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• hematologie a transfuzní lékařství