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Frédéric Bringaud - One of the best experts on this subject based on the ideXlab platform.
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the kinetic characteristics of human and Trypanosomatid phosphofructokinases for the reverse reaction
Biochemical Journal, 2019Co-Authors: Peter M Fernandes, James Kinkead, Frédéric Bringaud, Iain W. Mcnae, Paul A M Michels, Malcolm D WalkinshawAbstract:Eukaryotic ATP-dependent phosphofructokinases (PFKs) are often considered unidirectional enzymes catalysing the transfer of a phospho moiety from ATP to fructose 6-phosphate (F6P) to produce ADP and fructose 1,6-bisphosphate (F16BP). The reverse reaction is not generally considered to occur under normal conditions and has never been demonstrated for any eukaryotic ATP-dependent PFKs, though it does occur in PPi-dependent PFKs and has been experimentally shown for bacterial ATP-dependent PFKs. Evidence is provided via two orthogonal assays that all three human PFK isoforms can catalyse the reverse reaction in vitro , allowing determination of kinetic properties. Additionally, the reverse reaction was shown possible for PFKs from three clinically important Trypanosomatids; these enzymes are contained within glycosomes in vivo . This compartmentalisation may facilitate reversal, given the potential for Trypanosomatids to have an altered ATP/ADP ratio in glycosomes compared to the cytosol. The kinetic properties of each Trypanosomatid PFK were determined, including the response to natural and artificial modulators of enzyme activity. The possible physiological relevance of the reverse reaction in Trypanosomatid and human PFKs is discussed.
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The kinetic characteristics of human and Trypanosomatid phosphofructokinases for the reverse reaction.
Biochemical Journal, 2019Co-Authors: Peter M Fernandes, James Kinkead, Frédéric Bringaud, Iain W. Mcnae, Paul A M Michels, Malcolm D WalkinshawAbstract:Eukaryotic ATP-dependent phosphofructokinases (PFKs) are often considered unidirectional enzymes catalysing the transfer of a phospho moiety from ATP to fructose 6-phosphate to produce ADP and fructose 1,6-bisphosphate. The reverse reaction is not generally considered to occur under normal conditions and has never been demonstrated for any eukaryotic ATP-dependent PFKs, though it does occur in inorganic pyrophosphate-dependent PFKs and has been experimentally shown for bacterial ATP-dependent PFKs. The evidence is provided via two orthogonal assays that all three human PFK isoforms can catalyse the reverse reaction in vitro, allowing determination of kinetic properties. Additionally, the reverse reaction was shown possible for PFKs from three clinically important Trypanosomatids; these enzymes are contained within glycosomes in vivo. This compartmentalisation may facilitate reversal, given the potential for Trypanosomatids to have an altered ATP/ADP ratio in glycosomes compared with the cytosol. The kinetic properties of each Trypanosomatid PFK were determined, including the response to natural and artificial modulators of enzyme activity. The possible physiological relevance of the reverse reaction in Trypanosomatid and human PFKs is discussed.
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Kinetoplastid Phylogenomics Reveals the Evolutionary Innovations Associated with the Origins of Parasitism.
Current Biology, 2015Co-Authors: Andrew P Jackson, Thomas D. Otto, Martin Aslett, Stuart D. Armstrong, Alexander Schlacht, Catherine Hartley, Frédéric Bringaud, Mandy Sanders, Jonathan M Wastling, Joel B. DacksAbstract:The evolution of parasitism is a recurrent event in the history of life and a core problem in evolutionary biology. Trypanosomatids are important parasites and include the human pathogens Trypanosoma brucei, Trypanosoma cruzi, and Leishmania spp., which in humans cause African trypanosomiasis, Chagas disease, and leishmaniasis, respectively. Genome comparison between Trypanosomatids reveals that these parasites have evolved specialized cell-surface protein families, overlaid on a well-conserved cell template. Understanding how these features evolved and which ones are specifically associated with parasitism requires comparison with related non-parasites. We have produced genome sequences for Bodo saltans, the closest known non-parasitic relative of Trypanosomatids, and a second bodonid, Trypanoplasma borreli. Here we show how genomic reduction and innovation contributed to the character of Trypanosomatid genomes. We show that gene loss has “streamlined” Trypanosomatid genomes, particularly with respect to macromolecular degradation and ion transport, but consistent with a widespread loss of functional redundancy, while adaptive radiations of gene families involved in membrane function provide the principal innovations in Trypanosomatid evolution. Gene gain and loss continued during Trypanosomatid diversification, resulting in the asymmetric assortment of ancestral characters such as peptidases between Trypanosoma and Leishmania, genomic differences that were subsequently amplified by lineage-specific innovations after divergence. Finally, we show how species-specific, cell-surface gene families (DGF-1 and PSA) with no apparent structural similarity are independent derivations of a common ancestral form, which we call “bodonin.” This new evidence defines the parasitic innovations of Trypanosomatid genomes, revealing how a free-living phagotroph became adapted to exploiting hostile host environments.
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Identification and Analysis of Ingi-Related Retroposons in the Trypanosomatid Genomes
Methods in molecular biology (Clifton N.J.), 2014Co-Authors: Frédéric Bringaud, Matthew B. Rogers, Elodie GhedinAbstract:Transposable elements (TE), defined as discrete pieces of DNA that can move from one site to another site in genomes, represent significant components of eukaryotic genomes, including Trypanosomatids. Up to 5% of the Trypanosomatid genome content is composed of retroposons of the ingi clade, further divided into subclades and subfamilies ranging from short extinct truncated elements (SIDER) to long active elements (ingi). Important differences in ingi-related retroposon content have been reported between Trypanosomatid species. For instance, Leishmania spp. have expanded and recycled a whole SIDER family to fulfill an important biological pathway, i.e., regulation of gene expression, while trypanosome genomes are primarily composed of active elements. Here, we present an overview of the computational methods used to identify, annotate, and analyze ingi-related retroposons for providing a comprehensive picture of all these TE families in newly available Trypanosomatid genome sequences.
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Trypanosomatid genomes contain several subfamilies of ingi related retroposons
Eukaryotic Cell, 2009Co-Authors: Frédéric Bringaud, Matthew Berriman, Christiane HertzfowlerAbstract:Retroposons are ubiquitous transposable elements found in the genomes of most eukaryotes, including Trypanosomatids. The African and American trypanosomes (Trypanosoma brucei and Trypanosoma cruzi) contain long autonomous retroposons of the ingi clade (Tbingi and L1Tc, respectively) and short nonautonomous truncated versions (TbRIME and NARTc, respectively), as well as degenerate ingi-related retroposons devoid of coding capacity (DIREs). In contrast, Leishmania major contains only remnants of extinct retroposons (LmDIREs) and of short nonautonomous heterogeneous elements (LmSIDERs). We extend this comparative and evolutionary analysis of retroposons to the genomes of two other African trypanosomes (Trypanosoma congolense and Trypanosoma vivax) and another Leishmania sp. (Leishmania braziliensis). Three new potentially functional retroposons of the ingi clade have been identified: Tvingi in T. vivax and Tcoingi and L1Tco in T. congolense. T. congolense is the first Trypanosomatid containing two classes of potentially active retroposons of the ingi clade. We analyzed sequences located upstream of these new long autonomous ingi-related elements, which code for the recognition site of the retroposon-encoded endonuclease. The closely related Tcoingi and Tvingi elements show the same conserved pattern, indicating that the Tcoingi- and Tvingi-encoded endonucleases share site specificity. Similarly, the conserved pattern previously identified upstream of L1Tc has also been detected at the same relative position upstream of L1Tco elements. A phylogenetic analysis of all ingi-related retroposons identified so far, including DIREs, clearly shows that several distinct subfamilies have emerged and coexisted, though in the course of Trypanosomatid evolution, only a few have been maintained as active elements in modern Trypanosomatid (sub)species.
Julius Lukeš - One of the best experts on this subject based on the ideXlab platform.
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Insect Trypanosomatids in Papua New Guinea: high endemism and diversity
International journal for parasitology, 2019Co-Authors: Jana Králová, Julius Lukeš, Vyacheslav Yurchenko, Jan Votýpka, Anastasiia Grybchuk-ieremenko, Vojtěch Novotný, Petr Kment, Alexei Y. KostygovAbstract:The extreme biological diversity of Oceanian archipelagos has long stimulated research in ecology and evolution. However, parasitic protists in this geographic area remained neglected and no molecular analyses have been carried out to understand the evolutionary patterns and relationships with their hosts. Papua New Guinea (PNG) is a biodiversity hotspot containing over 5% of the world's biodiversity in less than 0.5% of the total land area. In the current work, we examined insect heteropteran hosts collected in PNG for the presence of Trypanosomatid parasites. The diversity of insect flagellates was analysed, to our knowledge for the first time, east of Wallace's Line, one of the most distinct biogeographic boundaries of the world. Out of 907 investigated specimens from 138 species and 23 families of the true bugs collected in eight localities, 135 (15%) were infected by at least one Trypanosomatid species. High species diversity of captured hosts correlated with high diversity of detected Trypanosomatids. Of 46 Trypanosomatid Typing Units documented in PNG, only eight were known from other geographic locations, while 38 TUs (~83%) have not been previously encountered. The widespread Trypanosomatid TUs were found in both widely distributed and endemic/sub-endemic insects. Approximately one-third of the endemic Trypanosomatid TUs were found in widely distributed hosts, while the remaining species were confined to endemic and sub-endemic insects. The TUs from PNG form clades with conspicuous host-parasite coevolutionary patterns, as well as those with a remarkable lack of this trait. In addition, our analysis revealed new members of the subfamilies Leishmaniinae and Strigomonadinae, potentially representing new genera of Trypanosomatids.
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An enigmatic catalase of Blastocrithidia.
Molecular and Biochemical Parasitology, 2019Co-Authors: Claretta Bianchi, Alexei Y. Kostygov, Natalya Kraeva, Kristína Záhonová, Eva Horáková, Roman Sobotka, Julius Lukeš, Vyacheslav YurchenkoAbstract:Abstract Here we report that Trypanosomatid flagellates of the genus Blastocrithidia possess catalase. This enzyme is not phylogenetically related to the previously characterized catalases in other monoxenous Trypanosomatids, suggesting that their genes have been acquired independently. Surprisingly, Blastocrithidia catalase is less enzymatically active, compared to its counterpart from Leptomonas pyrrhocoris , posing an intriguing biological question why this gene has been retained in the evolution of Trypanosomatids.
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High Prevalence and Endemism of Trypanosomatids on a Small Caribbean Island.
The Journal of eukaryotic microbiology, 2018Co-Authors: Jan Votýpka, Vyacheslav Yurchenko, Petr Kment, Eva Kriegová, Mark J. A. Vermeij, Patrick J. Keeling, Julius LukešAbstract:We describe the monoxenous Trypanosomatids parasitizing true bugs and flies on the island of Curacao. Out of 248 examined true bugs belonging to 17 species, 93 individuals were found to be infected (overall 38% prevalence) by at least one Trypanosomatid species (referred to as typing units; TUs). Out of 80 flies, six were infected. All detected Trypanosomatids were compared based on their 18S rRNA sequences with TUs parasitizing bugs and flies described from mainland South America, allowing us to assess their diversity and distribution. Besides Leptomonas pyrrhocoris and Leptomonas seymouri, two known species of the subfamily Leishmaniinae, our analysis revealed six new TUs falling into the groups ‘jaculum’, Blastocrithidia and Herpetomonas. Moreover, two new members of the genus Phytomonas and three new TUs belonging to the monophyletic group designated as ‘new clade II’ sensu Mol. Phylogenet. Evol, 69, 255 (2013) were isolated. The detected Trypanosomatids were characterized by moderate diversity (13 TUs) species richness. Out of nine and four TUs from the heteropteran and dipteran hosts, respectively, 11 TUs have not been encountered before. Although a sampling bias may partially affect the comparison between Trypanosomatid communities on Curacao and the mainland, the high proportion of unique TUs from the former location suggests that the prominent role of islands in increasing the global diversity of macroscopic organisms may also extend to their protistan parasites.
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extensive flagellar remodeling during the complex life cycle of paratrypanosoma an early branching Trypanosomatid
Proceedings of the National Academy of Sciences of the United States of America, 2017Co-Authors: Tomáš Skalický, Vyacheslav Yurchenko, Jan Votýpka, Pavel Flegontov, Eva Dobakova, Richard J Wheeler, Martina Tesařova, Dagmar Jirsova, Francisco J Ayala, Julius LukešAbstract:Paratrypanosoma confusum is a monoxenous kinetoplastid flagellate that constitutes the most basal branch of the highly diverse parasitic Trypanosomatids, which include human pathogens Trypanosoma and Leishmania This makes Paratrypanosoma uniquely informative for the evolution of obligatory parasitism from free-living lifestyle and the evolution of human parasitism in some Trypanosomatid lineages. It has typical promastigote morphology but also forms surface-attached haptomonads and amastigotes. Haptomonads form by attachment to a surface via a large bulge at the base of the flagellum, which is then remodeled into a thin attachment pad associated with flagellum shortening. Promastigotes and haptomonads multiply by binary division, and the progeny of a haptomonad can either remain attached or grow a flagellum and resume swimming. Whole genome sequencing and transcriptome profiling, in combination with analysis of the cell ultrastructure, reveal how the cell surface and metabolism are adapted to parasitism and how characteristic cytoskeletal features are conserved. Our data demonstrate that surface attachment by the flagellum and the flagellar pocket, a Leishmania-like flagellum attachment zone, and a Trypanosoma cruzi-like cytostome are ancestral features, while evolution of extant Trypanosomatids, including the human parasites, is associated with genome streamlining and diversification of membrane proteins.
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Infection Dynamics and Immune Response in a Newly Described Drosophila-Trypanosomatid Association
mBio, 2015Co-Authors: Phineas T. Hamilton, Julius Lukeš, Vyacheslav Yurchenko, Jan Votýpka, Anna Dostalova, Nathan H. Bird, Bruno Lemaitre, Steve J. PerlmanAbstract:Trypanosomatid parasites are significant causes of human disease and are ubiquitous in insects. Despite the impor- tance of Drosophila melanogaster as a model of infection and immunity and a long awareness that Trypanosomatid infection is common in the genus, no Trypanosomatid parasites naturally infecting Drosophilahave been characterized. Here, we establish a new model of Trypanosomatid infection in Drosophila—Jaenimonas drosophilae, gen. et sp. nov. As far as we are aware, this is thefirstDrosophila-parasitic Trypanosomatid to be cultured and characterized. Through experimental infections, wefind that Drosophila falleni, the natural host, is highly susceptible to infection, leading to a substantial decrease in host fecundity. J. droso- philae has a broad host range, readily infecting a number of Drosophila species, including D. melanogaster, with oral infection of D. melanogaster larvae resulting in the induction of numerous immune genes. When injected into adult hemolymph, J. droso- philae kills D. melanogaster, although interestingly, neither the Imd nor the Toll pathway is induced and Imd mutants do not show increased susceptibility to infection. In contrast, mutants deficient in drosocrystallin, a major component of the peritrophic matrix, are more severely infected during oral infection, suggesting that the peritrophic matrix plays an important role in mediating Trypanosomatid infection in Drosophila. This work demonstrates that the J. drosophilae-Drosophila system can be a powerful model to uncover the effects of Trypanosomatids in their insect hosts. IMPORTANCE Trypanosomatid parasites are ubiquitous in insects and are significant causes of disease when vectored to humans by blood-feeding insects. In recent decades, Drosophilahas emerged as the predominant insect model of infection and immunity and is also known to be infected by Trypanosomatids at high rates in the wild. Despite this, there has been almost no work on their Trypanosomatid parasites, in part because Drosophila-specific Trypanosomatids have been resistant to culturing. Here, we present thefirst isolation and detailed characterization of a Trypanosomatid from Drosophila,finding that it represents a new genus and species, Jaenimonas drosophilae. Using this parasite, we conducted a series of experiments that revealed many of the unknown aspects of Trypanosomatid infection in Drosophila, including host range, transmission biology, dynamics of infection, and host immune response. Taken together, this work establishes J. drosophilae as a powerful new opportunity to study trypano- somatid infections in insects.
Jan Votýpka - One of the best experts on this subject based on the ideXlab platform.
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Insect Trypanosomatids in Papua New Guinea: high endemism and diversity
International journal for parasitology, 2019Co-Authors: Jana Králová, Julius Lukeš, Vyacheslav Yurchenko, Jan Votýpka, Anastasiia Grybchuk-ieremenko, Vojtěch Novotný, Petr Kment, Alexei Y. KostygovAbstract:The extreme biological diversity of Oceanian archipelagos has long stimulated research in ecology and evolution. However, parasitic protists in this geographic area remained neglected and no molecular analyses have been carried out to understand the evolutionary patterns and relationships with their hosts. Papua New Guinea (PNG) is a biodiversity hotspot containing over 5% of the world's biodiversity in less than 0.5% of the total land area. In the current work, we examined insect heteropteran hosts collected in PNG for the presence of Trypanosomatid parasites. The diversity of insect flagellates was analysed, to our knowledge for the first time, east of Wallace's Line, one of the most distinct biogeographic boundaries of the world. Out of 907 investigated specimens from 138 species and 23 families of the true bugs collected in eight localities, 135 (15%) were infected by at least one Trypanosomatid species. High species diversity of captured hosts correlated with high diversity of detected Trypanosomatids. Of 46 Trypanosomatid Typing Units documented in PNG, only eight were known from other geographic locations, while 38 TUs (~83%) have not been previously encountered. The widespread Trypanosomatid TUs were found in both widely distributed and endemic/sub-endemic insects. Approximately one-third of the endemic Trypanosomatid TUs were found in widely distributed hosts, while the remaining species were confined to endemic and sub-endemic insects. The TUs from PNG form clades with conspicuous host-parasite coevolutionary patterns, as well as those with a remarkable lack of this trait. In addition, our analysis revealed new members of the subfamilies Leishmaniinae and Strigomonadinae, potentially representing new genera of Trypanosomatids.
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High Prevalence and Endemism of Trypanosomatids on a Small Caribbean Island.
The Journal of eukaryotic microbiology, 2018Co-Authors: Jan Votýpka, Vyacheslav Yurchenko, Petr Kment, Eva Kriegová, Mark J. A. Vermeij, Patrick J. Keeling, Julius LukešAbstract:We describe the monoxenous Trypanosomatids parasitizing true bugs and flies on the island of Curacao. Out of 248 examined true bugs belonging to 17 species, 93 individuals were found to be infected (overall 38% prevalence) by at least one Trypanosomatid species (referred to as typing units; TUs). Out of 80 flies, six were infected. All detected Trypanosomatids were compared based on their 18S rRNA sequences with TUs parasitizing bugs and flies described from mainland South America, allowing us to assess their diversity and distribution. Besides Leptomonas pyrrhocoris and Leptomonas seymouri, two known species of the subfamily Leishmaniinae, our analysis revealed six new TUs falling into the groups ‘jaculum’, Blastocrithidia and Herpetomonas. Moreover, two new members of the genus Phytomonas and three new TUs belonging to the monophyletic group designated as ‘new clade II’ sensu Mol. Phylogenet. Evol, 69, 255 (2013) were isolated. The detected Trypanosomatids were characterized by moderate diversity (13 TUs) species richness. Out of nine and four TUs from the heteropteran and dipteran hosts, respectively, 11 TUs have not been encountered before. Although a sampling bias may partially affect the comparison between Trypanosomatid communities on Curacao and the mainland, the high proportion of unique TUs from the former location suggests that the prominent role of islands in increasing the global diversity of macroscopic organisms may also extend to their protistan parasites.
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Trypanosomatid parasites in Austrian mosquitoes.
PloS one, 2018Co-Authors: Ellen Schoener, Sarah Susanne Uebleis, Claudia Cuk, Michaela Nawratil, Adelheid G. Obwaller, Thomas Zechmeister, Karin Lebl, Jana Rádrová, Carina Zittra, Jan VotýpkaAbstract: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.
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extensive flagellar remodeling during the complex life cycle of paratrypanosoma an early branching Trypanosomatid
Proceedings of the National Academy of Sciences of the United States of America, 2017Co-Authors: Tomáš Skalický, Vyacheslav Yurchenko, Jan Votýpka, Pavel Flegontov, Eva Dobakova, Richard J Wheeler, Martina Tesařova, Dagmar Jirsova, Francisco J Ayala, Julius LukešAbstract:Paratrypanosoma confusum is a monoxenous kinetoplastid flagellate that constitutes the most basal branch of the highly diverse parasitic Trypanosomatids, which include human pathogens Trypanosoma and Leishmania This makes Paratrypanosoma uniquely informative for the evolution of obligatory parasitism from free-living lifestyle and the evolution of human parasitism in some Trypanosomatid lineages. It has typical promastigote morphology but also forms surface-attached haptomonads and amastigotes. Haptomonads form by attachment to a surface via a large bulge at the base of the flagellum, which is then remodeled into a thin attachment pad associated with flagellum shortening. Promastigotes and haptomonads multiply by binary division, and the progeny of a haptomonad can either remain attached or grow a flagellum and resume swimming. Whole genome sequencing and transcriptome profiling, in combination with analysis of the cell ultrastructure, reveal how the cell surface and metabolism are adapted to parasitism and how characteristic cytoskeletal features are conserved. Our data demonstrate that surface attachment by the flagellum and the flagellar pocket, a Leishmania-like flagellum attachment zone, and a Trypanosoma cruzi-like cytostome are ancestral features, while evolution of extant Trypanosomatids, including the human parasites, is associated with genome streamlining and diversification of membrane proteins.
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Infection Dynamics and Immune Response in a Newly Described Drosophila-Trypanosomatid Association
mBio, 2015Co-Authors: Phineas T. Hamilton, Julius Lukeš, Vyacheslav Yurchenko, Jan Votýpka, Anna Dostalova, Nathan H. Bird, Bruno Lemaitre, Steve J. PerlmanAbstract:Trypanosomatid parasites are significant causes of human disease and are ubiquitous in insects. Despite the impor- tance of Drosophila melanogaster as a model of infection and immunity and a long awareness that Trypanosomatid infection is common in the genus, no Trypanosomatid parasites naturally infecting Drosophilahave been characterized. Here, we establish a new model of Trypanosomatid infection in Drosophila—Jaenimonas drosophilae, gen. et sp. nov. As far as we are aware, this is thefirstDrosophila-parasitic Trypanosomatid to be cultured and characterized. Through experimental infections, wefind that Drosophila falleni, the natural host, is highly susceptible to infection, leading to a substantial decrease in host fecundity. J. droso- philae has a broad host range, readily infecting a number of Drosophila species, including D. melanogaster, with oral infection of D. melanogaster larvae resulting in the induction of numerous immune genes. When injected into adult hemolymph, J. droso- philae kills D. melanogaster, although interestingly, neither the Imd nor the Toll pathway is induced and Imd mutants do not show increased susceptibility to infection. In contrast, mutants deficient in drosocrystallin, a major component of the peritrophic matrix, are more severely infected during oral infection, suggesting that the peritrophic matrix plays an important role in mediating Trypanosomatid infection in Drosophila. This work demonstrates that the J. drosophilae-Drosophila system can be a powerful model to uncover the effects of Trypanosomatids in their insect hosts. IMPORTANCE Trypanosomatid parasites are ubiquitous in insects and are significant causes of disease when vectored to humans by blood-feeding insects. In recent decades, Drosophilahas emerged as the predominant insect model of infection and immunity and is also known to be infected by Trypanosomatids at high rates in the wild. Despite this, there has been almost no work on their Trypanosomatid parasites, in part because Drosophila-specific Trypanosomatids have been resistant to culturing. Here, we present thefirst isolation and detailed characterization of a Trypanosomatid from Drosophila,finding that it represents a new genus and species, Jaenimonas drosophilae. Using this parasite, we conducted a series of experiments that revealed many of the unknown aspects of Trypanosomatid infection in Drosophila, including host range, transmission biology, dynamics of infection, and host immune response. Taken together, this work establishes J. drosophilae as a powerful new opportunity to study trypano- somatid infections in insects.
Vyacheslav Yurchenko - One of the best experts on this subject based on the ideXlab platform.
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cell cycle dependent flagellar disassembly in a firebug Trypanosomatid leptomonas pyrrhocoris
Mbio, 2019Co-Authors: Adarsh Singh, Vyacheslav YurchenkoAbstract:ABSTRACT Current understanding of flagellum/cilium length regulation focuses on a few model organisms with flagella of uniform length. Leptomonas pyrrhocoris is a monoxenous Trypanosomatid parasite of firebugs. When cultivated in vitro, L. pyrrhocoris duplicates every 4.2 ± 0.2 h, representing the shortest doubling time reported for Trypanosomatids so far. Each L. pyrrhocoris cell starts its cell cycle with a single flagellum. A new flagellum is assembled de novo, while the old flagellum persists throughout the cell cycle. The flagella in an asynchronous L. pyrrhocoris population exhibited a vast length variation of ∼3 to 24 μm, casting doubt on the presence of a length regulation mechanism based on a single balance point between the assembly and disassembly rate in these cells. Through imaging of live L. pyrrhocoris cells, a rapid, partial disassembly of the existing, old flagellum is observed upon, if not prior to, the initial assembly of a new flagellum. Mathematical modeling demonstrated an inverse correlation between the flagellar growth rate and flagellar length and inferred the presence of distinct, cell cycle-dependent disassembly mechanisms with different rates. On the basis of these observations, we proposed a min-max model that could account for the vast flagellar length range observed for asynchronous L. pyrrhocoris. This model may also apply to other flagellated organisms with flagellar length variation. IMPORTANCE Current understanding of flagellum biogenesis during the cell cycle in Trypanosomatids is limited to a few pathogenic species, including Trypanosoma brucei, Trypanosoma cruzi, and Leishmania spp. The most notable characteristics of Trypanosomatid flagella studied so far are the extreme stability and lack of ciliary disassembly/absorption during the cell cycle. This is different from cilia in Chlamydomonas and mammalian cells, which undergo complete absorption prior to cell cycle initiation. In this study, we examined flagellum duplication during the cell cycle of Leptomonas pyrrhocoris. With the shortest duplication time documented for all Trypanosomatidae and its amenability to culture on agarose gel with limited mobility, we were able to image these cells through the cell cycle. Rapid, cell cycle-specific flagellum disassembly different from turnover was observed for the first time in Trypanosomatids. Given the observed length-dependent growth rate and the presence of different disassembly mechanisms, we proposed a min-max model that can account for the flagellar length variation observed in L. pyrrhocoris.
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Insect Trypanosomatids in Papua New Guinea: high endemism and diversity
International journal for parasitology, 2019Co-Authors: Jana Králová, Julius Lukeš, Vyacheslav Yurchenko, Jan Votýpka, Anastasiia Grybchuk-ieremenko, Vojtěch Novotný, Petr Kment, Alexei Y. KostygovAbstract:The extreme biological diversity of Oceanian archipelagos has long stimulated research in ecology and evolution. However, parasitic protists in this geographic area remained neglected and no molecular analyses have been carried out to understand the evolutionary patterns and relationships with their hosts. Papua New Guinea (PNG) is a biodiversity hotspot containing over 5% of the world's biodiversity in less than 0.5% of the total land area. In the current work, we examined insect heteropteran hosts collected in PNG for the presence of Trypanosomatid parasites. The diversity of insect flagellates was analysed, to our knowledge for the first time, east of Wallace's Line, one of the most distinct biogeographic boundaries of the world. Out of 907 investigated specimens from 138 species and 23 families of the true bugs collected in eight localities, 135 (15%) were infected by at least one Trypanosomatid species. High species diversity of captured hosts correlated with high diversity of detected Trypanosomatids. Of 46 Trypanosomatid Typing Units documented in PNG, only eight were known from other geographic locations, while 38 TUs (~83%) have not been previously encountered. The widespread Trypanosomatid TUs were found in both widely distributed and endemic/sub-endemic insects. Approximately one-third of the endemic Trypanosomatid TUs were found in widely distributed hosts, while the remaining species were confined to endemic and sub-endemic insects. The TUs from PNG form clades with conspicuous host-parasite coevolutionary patterns, as well as those with a remarkable lack of this trait. In addition, our analysis revealed new members of the subfamilies Leishmaniinae and Strigomonadinae, potentially representing new genera of Trypanosomatids.
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An enigmatic catalase of Blastocrithidia.
Molecular and Biochemical Parasitology, 2019Co-Authors: Claretta Bianchi, Alexei Y. Kostygov, Natalya Kraeva, Kristína Záhonová, Eva Horáková, Roman Sobotka, Julius Lukeš, Vyacheslav YurchenkoAbstract:Abstract Here we report that Trypanosomatid flagellates of the genus Blastocrithidia possess catalase. This enzyme is not phylogenetically related to the previously characterized catalases in other monoxenous Trypanosomatids, suggesting that their genes have been acquired independently. Surprisingly, Blastocrithidia catalase is less enzymatically active, compared to its counterpart from Leptomonas pyrrhocoris , posing an intriguing biological question why this gene has been retained in the evolution of Trypanosomatids.
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High Prevalence and Endemism of Trypanosomatids on a Small Caribbean Island.
The Journal of eukaryotic microbiology, 2018Co-Authors: Jan Votýpka, Vyacheslav Yurchenko, Petr Kment, Eva Kriegová, Mark J. A. Vermeij, Patrick J. Keeling, Julius LukešAbstract:We describe the monoxenous Trypanosomatids parasitizing true bugs and flies on the island of Curacao. Out of 248 examined true bugs belonging to 17 species, 93 individuals were found to be infected (overall 38% prevalence) by at least one Trypanosomatid species (referred to as typing units; TUs). Out of 80 flies, six were infected. All detected Trypanosomatids were compared based on their 18S rRNA sequences with TUs parasitizing bugs and flies described from mainland South America, allowing us to assess their diversity and distribution. Besides Leptomonas pyrrhocoris and Leptomonas seymouri, two known species of the subfamily Leishmaniinae, our analysis revealed six new TUs falling into the groups ‘jaculum’, Blastocrithidia and Herpetomonas. Moreover, two new members of the genus Phytomonas and three new TUs belonging to the monophyletic group designated as ‘new clade II’ sensu Mol. Phylogenet. Evol, 69, 255 (2013) were isolated. The detected Trypanosomatids were characterized by moderate diversity (13 TUs) species richness. Out of nine and four TUs from the heteropteran and dipteran hosts, respectively, 11 TUs have not been encountered before. Although a sampling bias may partially affect the comparison between Trypanosomatid communities on Curacao and the mainland, the high proportion of unique TUs from the former location suggests that the prominent role of islands in increasing the global diversity of macroscopic organisms may also extend to their protistan parasites.
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farming slaving and enslavement histories of endosymbioses during kinetoplastid evolution
Parasitology, 2018Co-Authors: Jeffrey Harmer, Anna Nenarokova, Vyacheslav Yurchenko, Michael L GingerAbstract:Parasitic Trypanosomatids diverged from free-living kinetoplastid ancestors several hundred million years ago. These parasites are relatively well known, due in part to several unusual cell biological and molecular traits and in part to the significance of a few – pathogenic Leishmania and Trypanosoma species – as aetiological agents of serious neglected tropical diseases. However, the majority of Trypanosomatid biodiversity is represented by osmotrophic monoxenous parasites of insects. In two lineages, novymonads and strigomonads, osmotrophic lifestyles are supported by cytoplasmic endosymbionts, providing hosts with macromolecular precursors and vitamins. Here we discuss the two independent origins of endosymbiosis within Trypanosomatids and subsequently different evolutionary trajectories that see entrainment vs tolerance of symbiont cell divisions cycles within those of the host. With the potential to inform on the transition to obligate parasitism in the Trypanosomatids, interest in the biology and ecology of free-living, phagotrophic kinetoplastids is beginning to enjoy a renaissance. Thus, we take the opportunity to additionally consider the wider relevance of endosymbiosis during kinetoplastid evolution, including the indulged lifestyle and reductive evolution of basal kinetoplastid Perkinsela.
Malcolm D Walkinshaw - One of the best experts on this subject based on the ideXlab platform.
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the kinetic characteristics of human and Trypanosomatid phosphofructokinases for the reverse reaction
Biochemical Journal, 2019Co-Authors: Peter M Fernandes, James Kinkead, Frédéric Bringaud, Iain W. Mcnae, Paul A M Michels, Malcolm D WalkinshawAbstract:Eukaryotic ATP-dependent phosphofructokinases (PFKs) are often considered unidirectional enzymes catalysing the transfer of a phospho moiety from ATP to fructose 6-phosphate (F6P) to produce ADP and fructose 1,6-bisphosphate (F16BP). The reverse reaction is not generally considered to occur under normal conditions and has never been demonstrated for any eukaryotic ATP-dependent PFKs, though it does occur in PPi-dependent PFKs and has been experimentally shown for bacterial ATP-dependent PFKs. Evidence is provided via two orthogonal assays that all three human PFK isoforms can catalyse the reverse reaction in vitro , allowing determination of kinetic properties. Additionally, the reverse reaction was shown possible for PFKs from three clinically important Trypanosomatids; these enzymes are contained within glycosomes in vivo . This compartmentalisation may facilitate reversal, given the potential for Trypanosomatids to have an altered ATP/ADP ratio in glycosomes compared to the cytosol. The kinetic properties of each Trypanosomatid PFK were determined, including the response to natural and artificial modulators of enzyme activity. The possible physiological relevance of the reverse reaction in Trypanosomatid and human PFKs is discussed.
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The kinetic characteristics of human and Trypanosomatid phosphofructokinases for the reverse reaction.
Biochemical Journal, 2019Co-Authors: Peter M Fernandes, James Kinkead, Frédéric Bringaud, Iain W. Mcnae, Paul A M Michels, Malcolm D WalkinshawAbstract:Eukaryotic ATP-dependent phosphofructokinases (PFKs) are often considered unidirectional enzymes catalysing the transfer of a phospho moiety from ATP to fructose 6-phosphate to produce ADP and fructose 1,6-bisphosphate. The reverse reaction is not generally considered to occur under normal conditions and has never been demonstrated for any eukaryotic ATP-dependent PFKs, though it does occur in inorganic pyrophosphate-dependent PFKs and has been experimentally shown for bacterial ATP-dependent PFKs. The evidence is provided via two orthogonal assays that all three human PFK isoforms can catalyse the reverse reaction in vitro, allowing determination of kinetic properties. Additionally, the reverse reaction was shown possible for PFKs from three clinically important Trypanosomatids; these enzymes are contained within glycosomes in vivo. This compartmentalisation may facilitate reversal, given the potential for Trypanosomatids to have an altered ATP/ADP ratio in glycosomes compared with the cytosol. The kinetic properties of each Trypanosomatid PFK were determined, including the response to natural and artificial modulators of enzyme activity. The possible physiological relevance of the reverse reaction in Trypanosomatid and human PFKs is discussed.
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Trypanosomatid phosphoglycerate mutases have multiple conformational and oligomeric states
Biochemical and Biophysical Research Communications, 2014Co-Authors: Elizabeth A Blackburn, Paul A M Michels, Fazia Adyani Ahmad Fuad, Hugh P Morgan, Matthew W Nowicki, Martin A Wear, Linda A Fothergillgilmore, Malcolm D WalkinshawAbstract:Three structurally distinct forms of phosphoglycerate mutase from the Trypanosomatid parasite Leishmania mexicana were isolated by standard procedures of bacterial expression and purification. Analytical size-exclusion chromatography coupled to a multi-angle scattering detector detected two monomeric forms of differing hydrodynamic radii, as well as a dimeric form. Structural comparisons of holoenzyme and apoenzyme Trypanosomatid cofactor-independent phosphoglycerate mutase (iPGAM) X-ray crystal structures show a large conformational change between the open (apoenzyme) and closed (holoenzyme) forms accounting for the different monomer hydrodynamic radii. Until now iPGAM from Trypanosomatids was considered to be only monomeric, but results presented here show the appearance of a dimeric form. Taken together, these observations are important for the choice of screening strategies to identify inhibitors of iPGAM for parasite chemotherapy and highlight the need to select the most biologically or functionally relevant form of the purified enzyme.