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: Amphibian trypanosomes were the first ever described trypanosomatids. Nevertheless, their taxonomy remains entangled because of pleomorphism and high prevalence of mixed infections. Despite the fact that the first species in this group were described in Europe, virtually none of the trypanosomes from European anurans was analyzed using modern molecular methods. METHODS: In this study, we explored the diversity and phylogeny of trypanosomes in true frogs from Europe using light microscopy and molecular methods. RESULTS: A comparison of observed morphotypes with previous descriptions allowed us to reliably identify three Trypanosoma spp., whereas the remaining two strains were considered to represent novel taxa. In all cases, more than one morphotype per blood sample was observed, indicating mixed infections. One hundred and thirty obtained 18S rRNA gene sequences were unambiguously subdivided into five groups, correspondent to the previously recognized or novel taxa of anuran trypanosomes. CONCLUSIONS: In this work we studied European frog trypanosomes. Even with a relatively moderate number of isolates, we were able to find not only three well-known species, but also two apparently new ones. We revealed that previous assignments of multiple isolates from distant geographical localities to one species based on superficial resemblance were unjustified. Our work also demonstrated a high prevalence of mixed trypanosome infections in frogs and proposed a plausible scenario of evolution of the genus Trypanosoma.

• Klíčová slova
• Evolution, Frog trypanosomes, Mixed infections, Trypanosomatidae,
• MeSH
• druhová specificita MeSH
• fylogeneze * MeSH
• genetická variace MeSH
• klonování DNA MeSH
• polymerázová řetězová reakce MeSH
• RNA protozoální genetika   MeSH
• RNA ribozomální 18S genetika   MeSH
• Trypanosoma genetika   fyziologie   MeSH
• žáby krev   parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Československo MeSH
• Ukrajina MeSH
• Názvy látek
• RNA protozoální MeSH
• RNA ribozomální 18S MeSH

The class Kinetoplastea encompasses both free-living and parasitic species from a wide range of hosts. Several representatives of this group are responsible for severe human diseases and for economic losses in agriculture and livestock. While this group encompasses over 30 genera, most of the available information has been derived from the vertebrate pathogenic genera Leishmaniaand Trypanosoma. Recent studies of the previously neglected groups of Kinetoplastea indicated that the actual diversity is much higher than previously thought. This article discusses the known segment of kinetoplastid diversity and how gene-directed Sanger sequencing and next-generation sequencing methods can help to deepen our knowledge of these interesting protists.

• MeSH
• biodiverzita * MeSH
• biologické markery MeSH
• databáze genetické MeSH
• fylogeneze * MeSH
• Kinetoplastida klasifikace   cytologie   genetika   MeSH
• metagenomika trendy   MeSH
• protozoální DNA genetika   MeSH
• RNA protozoální genetika   MeSH
• RNA ribozomální 18S genetika   MeSH
• taxonomické DNA čárové kódování trendy   MeSH
• výpočetní biologie MeSH
• vysoce účinné nukleotidové sekvenování metody   MeSH
• životní prostředí MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• biologické markery MeSH
• protozoální DNA MeSH
• RNA protozoální MeSH
• RNA ribozomální 18S MeSH

• MeSH
• biologická evoluce MeSH
• Crithidia fasciculata genetika   ultrastruktura   MeSH
• elektronová mikroskopie MeSH
• fylogeneze MeSH
• Kinetoplastida genetika   ultrastruktura   MeSH
• kinetoplastová DNA genetika   ultrastruktura   MeSH
• Trypanosoma genetika   ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, U.S. Gov't, P.H.S. MeSH
• Názvy látek
• kinetoplastová DNA MeSH

The mitochondrial DNA (mtDNA) of a primitive kinetoplastid flagellate Cryptobia helicis is composed of 4.2 kb minicircles and 43 kb maxicircles. 85% and 6% of the minicircles are in the form of supercoiled (SC) and relaxed (OC) monomers, respectively. The remaining minicircles (9%) constitute catenated oligomers composed of both the SC and OC molecules. Minicircles contain bent helix and sequences homologous to the minicircle conserved sequence blocks. Maxicircles encode typical mitochondrial genes and are not catenated. The mtDNA, which we describe with the term 'pankinetoplast DNA', is spread throughout the mitochondrial lumen, where it is associated with multiple electron-lucent loci. There are approximately 8400 minicircles per pankinetoplast-mitochondrion, with the pan-kDNA representing approximately 36% of the total cellular DNA. Based on the similarity of the C.helicis minicircles to plasmids, we present a theory on the formation of the kDNA network.

• MeSH
• elektronová mikroskopie MeSH
• Kinetoplastida genetika   ultrastruktura   MeSH
• kinetoplastová DNA chemie   genetika   ultrastruktura   MeSH
• konformace nukleové kyseliny MeSH
• kruhová DNA analýza   MeSH
• mitochondriální DNA ultrastruktura   MeSH
• mitochondrie genetika   ultrastruktura   MeSH
• protozoální DNA analýza   chemie   ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kinetoplastová DNA MeSH
• kruhová DNA MeSH
• mitochondriální DNA MeSH
• protozoální DNA MeSH