Euglenozoa is a species-rich group of protists, which have extremely diverse lifestyles and a range of features that distinguish them from other eukaryotes. They are composed of free-living and parasitic kinetoplastids, mostly free-living diplonemids, heterotrophic and photosynthetic euglenids, as well as deep-sea symbiontids. Although they form a well-supported monophyletic group, these morphologically rather distinct groups are almost never treated together in a comparative manner, as attempted here. We present an updated taxonomy, complemented by photos of representative species, with notes on diversity, distribution and biology of euglenozoans. For kinetoplastids, we propose a significantly modified taxonomy that reflects the latest findings. Finally, we summarize what is known about viruses infecting euglenozoans, as well as their relationships with ecto- and endosymbiotic bacteria.

• Klíčová slova
• Diplonemida, Euglenida, Kinetoplastida, microbial eukaryotes, phylogeny, systematics,
• MeSH
• ekosystém MeSH
• Euglenozoa klasifikace   genetika   fyziologie   virologie   MeSH
• fylogeneze MeSH
• Mimiviridae patogenita   MeSH
• symbióza MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

BACKGROUND: The family Trypanosomatidae encompasses parasitic flagellates, some of which cause serious vector-transmitted diseases of humans and domestic animals. However, insect-restricted parasites represent the ancestral and most diverse group within the family. They display a range of unusual features and their study can provide insights into the biology of human pathogens. Here we describe Vickermania, a new genus of fly midgut-dwelling parasites that bear two flagella in contrast to other trypanosomatids, which are unambiguously uniflagellate. RESULTS: Vickermania has an odd cell cycle, in which shortly after the division the uniflagellate cell starts growing a new flagellum attached to the old one and preserves their contact until the late cytokinesis. The flagella connect to each other throughout their whole length and carry a peculiar seizing structure with a paddle-like apex and two lateral extensions at their tip. In contrast to typical trypanosomatids, which attach to the insect host's intestinal wall, Vickermania is separated from it by a continuous peritrophic membrane and resides freely in the fly midgut lumen. CONCLUSIONS: We propose that Vickermania developed a survival strategy that relies on constant movement preventing discharge from the host gut due to intestinal peristalsis. Since these parasites cannot attach to the midgut wall, they were forced to shorten the period of impaired motility when two separate flagella in dividing cells interfere with each other. The connection between the flagella ensures their coordinate movement until the separation of the daughter cells. We propose that Trypanosoma brucei, a severe human pathogen, during its development in the tsetse fly midgut faces the same conditions and follows the same strategy as Vickermania by employing an analogous adaptation, the flagellar connector.

• Klíčová slova
• Cell cycle, Flagella connector, Herpetomonas muscarum ingenoplastis, Trypanosoma brucei,
• MeSH
• flagella fyziologie   MeSH
• interakce hostitele a parazita * MeSH
• moucha tse-tse parazitologie   MeSH
• peristaltika MeSH
• Trypanosomatina klasifikace   cytologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In this work, we describe the first Leishmania-infecting leishbunyavirus-the first virus other than Leishmania RNA virus (LRV) found in trypanosomatid parasites. Its host is Leishmaniamartiniquensis, a human pathogen causing infections with a wide range of manifestations from asymptomatic to severe visceral disease. This virus (LmarLBV1) possesses many characteristic features of leishbunyaviruses, such as tripartite organization of its RNA genome, with ORFs encoding RNA-dependent RNA polymerase, surface glycoprotein, and nucleoprotein on L, M, and S segments, respectively. Our phylogenetic analyses suggest that LmarLBV1 originated from leishbunyaviruses of monoxenous trypanosomatids and, probably, is a result of genomic re-assortment. The LmarLBV1 facilitates parasites' infectivity in vitro in primary murine macrophages model. The discovery of a virus in L.martiniquensis poses the question of whether it influences pathogenicity of this parasite in vivo, similarly to the LRV in other Leishmania species.

• Klíčová slova
• Bunyavirales, Leishmania martiniquensis, leishbunyavirus,
• MeSH
• fylogeneze * MeSH
• genom virový * MeSH
• Leishmania patogenita   virologie   MeSH
• makrofágy parazitologie   MeSH
• myši MeSH
• otevřené čtecí rámce MeSH
• reassortantní viry MeSH
• RNA-dependentní RNA-polymerasa MeSH
• RNA-viry klasifikace   genetika   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• RNA-dependentní RNA-polymerasa MeSH

Trypanosomatid flagellates have not been studied in Austria in any detail. In this study, specific nested PCR, targeted on the ribosomal small subunit, was used to determine the occurrence and diversity of trypanosomatids in wild-caught mosquitoes sampled across Eastern Austria in the years 2014-2015. We collected a total of 29,975 mosquitoes of 19 species divided in 1680 pools. Of these, 298 (17.7%), representing 12 different mosquito species, were positive for trypanosomatid DNA. In total, seven trypanosomatid spp. were identified (three Trypanosoma, three Crithidia and one Herpetomonas species), with the highest parasite species diversity found in the mosquito host Coquillettidia richiardii. The most frequent parasite species belonged to the mammalian Trypanosoma theileri/cervi species complex (found in 105 pools; 6.3%). The avian species T. culicavium (found in 69 pools; 4.1%) was only detected in mosquitoes of the genus Culex, which corresponds to their preference for avian hosts. Monoxenous trypanosomatids of the genus Crithidia and Herpetomonas were found in 20 (1.3%) mosquito pools. One third (n = 98) of the trypanosomatid positive mosquito pools carried more than one parasite species. This is the first large scale study of trypanosomatid parasites in Austrian mosquitoes and our results are valuable in providing an overview of the diversity of these parasites in Austria.

• MeSH
• biodiverzita MeSH
• Culicidae parazitologie   MeSH
• fylogeneze MeSH
• protozoální DNA MeSH
• ribozomální DNA MeSH
• sekvenční analýza DNA MeSH
• Trypanosoma klasifikace   genetika   MeSH
• trypanozomiáza parazitologie   přenos   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Rakousko MeSH
• Názvy látek
• protozoální DNA MeSH
• ribozomální DNA MeSH

BACKGROUND: Although avian trypanosomes are widespread parasites, the knowledge of their vectors is still incomplete. Despite biting midges (Diptera: Ceratopogonidae) are considered as potential vectors of avian trypanosomes, their role in transmission has not been satisfactorily elucidated. Our aim was to clarify the potential of biting midges to sustain the development of avian trypanosomes by testing their susceptibility to different strains of avian trypanosomes experimentally. Moreover, we screened biting midges for natural infections in the wild. RESULTS: Laboratory-bred biting midges Culicoides nubeculosus were highly susceptible to trypanosomes from the Trypanosoma bennetti and T. avium clades. Infection rates reached 100%, heavy infections developed in 55-87% of blood-fed females. Parasite stages from the insect gut were infective for birds. Moreover, midges could be infected after feeding on a trypanosome-positive bird. Avian trypanosomes can thus complete their cycle in birds and biting midges. Furthermore, we succeeded to find infected blood meal-free biting midges in the wild. CONCLUSIONS: Biting midges are probable vectors of avian trypanosomes belonging to T. bennetti group. Midges are highly susceptible to artificial infections, can be infected after feeding on birds, and T. bennetti-infected biting midges (Culicoides spp.) have been found in nature. Moreover, midges can be used as model hosts producing metacyclic avian trypanosome stages infective for avian hosts.

• Klíčová slova
• Avian parasite, Culicoides nubeculosus, Host specificity, Life-cycle, Transmission, Trypanosoma avium, Trypanosoma bennetti, Trypanosoma culicavium,
• MeSH
• Ceratopogonidae anatomie a histologie   parazitologie   MeSH
• gastrointestinální trakt parazitologie   MeSH
• hmyz - vektory parazitologie   MeSH
• hostitelská specificita MeSH
• kanáři parazitologie   MeSH
• mikroskopie elektronová rastrovací MeSH
• nemoci ptáků parazitologie   přenos   MeSH
• polymerázová řetězová reakce MeSH
• ptáci parazitologie   MeSH
• Trypanosoma klasifikace   genetika   fyziologie   ultrastruktura   MeSH
• trypanozomiáza diagnóza   parazitologie   přenos   veterinární   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH