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Shyam Sundar - One of the best experts on this subject based on the ideXlab platform.
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Leptomonas seymouri narna-like virus 1 and not leishmaniaviruses detected in kala-azar samples from India
Archives of Virology, 2017Co-Authors: Soumi Sukla, Shyam Sundar, Subhajit BiswasAbstract:The great majority of kala-azar/visceral leishmaniasis (VL) cases, which are caused by Leishmania donovani (LD), are reported in Asia. We investigated whether leishmaniaviruses (LRVs) are present in LD isolates. These dsRNA viruses contribute to hyperpathogenicity, as observed in the case of other members of the genus Leishmania . However, LRVs could not be detected in 22 Indian LD isolates tested in the present study, while 70% of these original LD isolates harboured a virus that was not of LD but instead of Leptomonas seymouri (LS) origin. LS is another protozoon that parasitizes the sandfly vector of LD. Historically, LD clinical isolates from India often showed high incidence of LS coinfection. LS was detected in 20 out of the 22 (91%) above-mentioned LD isolates. Leptomonas seymouri narna-like virus 1 (Lepsey NLV1) was identified by whole-genome sequencing in an LD-LS coinfected sample, and its presence was confirmed by PCR and sequencing in 15 (75%) of the 20 LD-LS coinfected samples. The LS-negative LD samples were also virus negative by PCR. That the human host is exposed to an RNA virus in LS, another coinfecting parasite with LD, i.e., the “LD-LS-Lepsey NLV1 triple pathogen” phenomenon, unveils a new paradigm of research towards revisiting the mysteries of Indian leishmaniasis pathogenesis and management.
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SOLiDTM sequencing of genomes of clinical isolates of leishmania donovani from india confirm Leptomonas co-infection and raise some key questions. PLoS One
2016Co-Authors: Neeloo Singh, Surendra Chikara, Shyam SundarAbstract:Background: Known as ‘neglected disease ’ because relatively little effort has been applied to finding cures, leishmaniasis kills more than 150,000 people every year and debilitates millions more. Visceral leishmaniasis (VL), also called Kala Azar (KA) or black fever in India, claims around 20,000 lives every year. Whole genome analysis presents an excellent means to identify new targets for drugs, vaccine and diagnostics development, and also provide an avenue into the biological basis of parasite virulence in the L. donovani complex prevalent in India. Methodology/Principal Findings: In our presently described study, the next generation SOLiDTM platform was successfully utilized for the first time to carry out whole genome sequencing of L. donovani clinical isolates from India. We report the exceptional occurrence of insect trypanosomatids in clinical cases of visceral leishmaniasis (Kala Azar) patients in India. We confirm with whole genome sequencing analysis data that isolates which were sequenced from Kala Azar (visceral leishmaniasis) cases were genetically related to Leptomonas. The co-infection in splenic aspirate of these patients with a species of Leptomonas and how likely is it that the infection might be pathogenic, are key questions which need to be investigated. We discuss our results in the context of some important probable hypothesis in this article. Conclusions/Significance: Our intriguing results of unusual cases of Kala Azar found to be most similar to Leptomonas species put forth important clinical implications for the treatment of Kala Azar in India. Leptomonas have been shown to b
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solid sequencing of genomes of clinical isolates of leishmania donovani from india confirm Leptomonas co infection and raise some key questions
PLOS ONE, 2013Co-Authors: Neeloo Singh, Surendra Chikara, Shyam SundarAbstract:Background Known as ‘neglected disease’ because relatively little effort has been applied to finding cures, leishmaniasis kills more than 150,000 people every year and debilitates millions more. Visceral leishmaniasis (VL), also called Kala Azar (KA) or black fever in India, claims around 20,000 lives every year. Whole genome analysis presents an excellent means to identify new targets for drugs, vaccine and diagnostics development, and also provide an avenue into the biological basis of parasite virulence in the L. donovani complex prevalent in India. Methodology/Principal Findings In our presently described study, the next generation SOLiD™ platform was successfully utilized for the first time to carry out whole genome sequencing of L. donovani clinical isolates from India. We report the exceptional occurrence of insect trypanosomatids in clinical cases of visceral leishmaniasis (Kala Azar) patients in India. We confirm with whole genome sequencing analysis data that isolates which were sequenced from Kala Azar (visceral leishmaniasis) cases were genetically related to Leptomonas. The co-infection in splenic aspirate of these patients with a species of Leptomonas and how likely is it that the infection might be pathogenic, are key questions which need to be investigated. We discuss our results in the context of some important probable hypothesis in this article. Conclusions/Significance Our intriguing results of unusual cases of Kala Azar found to be most similar to Leptomonas species put forth important clinical implications for the treatment of Kala Azar in India. Leptomonas have been shown to be highly susceptible to several standard leishmaniacides in vitro. There is very little divergence among these two species viz. Leishmania sp. and L. seymouri, in terms of genomic sequence and organization. A more extensive perception of the phenomenon of co-infection needs to be addressed from molecular pathogenesis and eco-epidemiological standpoint.
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Mapping statistics of reads with Leptomonas and L. donovani Nepal isolate Ld_BPK282A1.
2013Co-Authors: Neeloo Singh, Surendra Chikara, Shyam SundarAbstract:Mapping statistics of reads with Leptomonas and L. donovani Nepal isolate Ld_BPK282A1.
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Statistics of genome coverage in percentage and bases with Leptomonas and L. donovani Nepal isolate Ld_BPK282A1.
2013Co-Authors: Neeloo Singh, Surendra Chikara, Shyam SundarAbstract:Statistics of genome coverage in percentage and bases with Leptomonas and L. donovani Nepal isolate Ld_BPK282A1.
Neeloo Singh - One of the best experts on this subject based on the ideXlab platform.
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differential metabolic pathway analysis of the proteomes of leishmania donovani and Leptomonas seymouri
Proteomics Clinical Applications, 2018Co-Authors: Neeloo Singh, Renu Goel, Ekta JainAbstract:PURPOSE Although in trypanosomatids, monoxeny (Leptomonas) is ancestral to dixeny (Leishmania), however clinical cases of visceral leishmanisis with Leptomonas co-infection are increasingly being reported from India. Using a proteogenomic approach, a detailed proteome analysis of these two kinetoplastid parasites viz., Leishmania and its sister Leptomonas, to catalog the key proteins associated with and therefore possibly responsible for phenotype changes in Leptomonas evolution and domestication as co-infection with Leishmania is carried out. EXPERIMENTAL DESIGN LC-MS/MS is utilized for this proteomic purpose. One Leishmania donovani WHO reference strain and two Leptomonas seymouri isolates, which are originally isolated from clinical cases of kala azar patients with different inherent drug sensitivity viz., responsive and unresponsive, are used in this study. RESULTS A network analysis, leveraging protein-protein interaction data helped to find the roles of the proteins in carbon metabolism and biosynthesis of secondary metabolites which is seen to be altered under stress conditions like drug resistance. CONCLUSIONS AND CLINICAL RELEVANCE The information provided about the metabolic pathways modulated when contrasting these two phenotypes may lead to the development of new strategies to block parasite differentiation within the host and to also circumvent the problem of drug resistance. This proteomic study also offers new grounds for the investigation of novel hypothetical proteins potentially playing a role in evolutionary biology the knowledge of which is essential for treatment of patients co-infected with these two kinetoplastid parasites.
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SOLiDTM sequencing of genomes of clinical isolates of leishmania donovani from india confirm Leptomonas co-infection and raise some key questions. PLoS One
2016Co-Authors: Neeloo Singh, Surendra Chikara, Shyam SundarAbstract:Background: Known as ‘neglected disease ’ because relatively little effort has been applied to finding cures, leishmaniasis kills more than 150,000 people every year and debilitates millions more. Visceral leishmaniasis (VL), also called Kala Azar (KA) or black fever in India, claims around 20,000 lives every year. Whole genome analysis presents an excellent means to identify new targets for drugs, vaccine and diagnostics development, and also provide an avenue into the biological basis of parasite virulence in the L. donovani complex prevalent in India. Methodology/Principal Findings: In our presently described study, the next generation SOLiDTM platform was successfully utilized for the first time to carry out whole genome sequencing of L. donovani clinical isolates from India. We report the exceptional occurrence of insect trypanosomatids in clinical cases of visceral leishmaniasis (Kala Azar) patients in India. We confirm with whole genome sequencing analysis data that isolates which were sequenced from Kala Azar (visceral leishmaniasis) cases were genetically related to Leptomonas. The co-infection in splenic aspirate of these patients with a species of Leptomonas and how likely is it that the infection might be pathogenic, are key questions which need to be investigated. We discuss our results in the context of some important probable hypothesis in this article. Conclusions/Significance: Our intriguing results of unusual cases of Kala Azar found to be most similar to Leptomonas species put forth important clinical implications for the treatment of Kala Azar in India. Leptomonas have been shown to b
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RESEARCH ARTICLE Open Access Evolutionary comparison of prenylation pathway in kinetoplastid Leishmania and its
2016Co-Authors: Sister Leptomonas, Jaspreet Kaur, Shagun Krishna, Arpita Ghosh, Prashant Singh, Indira Singh Chauhan, Mohammad Imran Siddiqi, Neeloo SinghAbstract:Background: Leptomonas is monogenetic kinetoplastid parasite of insects and is primitive in comparison to Leishmania. Comparative studies of these two kinetoplastid may share light on the evolutionary transition to dixenous parasitism in Leishmania. In order to adapt and survive within two hosts, Leishmania species must have acquired virulence factors in addition to mechanisms that mediate susceptibility/resistance to infection in the pathology associated with disease. Rab proteins are key mediators of vesicle transport and contribute greatly to the evolution of complexity of membrane transport system. In this study we used our whole genome sequence data of these two divergent kinetoplastids to analyze the orthologues/paralogues of Rab proteins. Results: During change of lifestyle from monogenetic (Leptomonas) to digenetic (Leishmania), we found that the prenyl machinery remained unchanged. Geranylgeranyl transferase-I (GGTase-I) was absent in both Leishmania and its sister Leptomonas. Farnesyltransferase (FTase) and geranylgeranyl transferase-II (GGTase-II) were identified for protein prenylation. We predict that activity of the missing alpha-subunit (α-subunit) of GGTase-II in Leptomonas was probably contributed by the α-subunit of FTase, while beta-subunit (β-subunit) of GGTase-II was conserved and indicated functional conservation in the evolution of these two kinetoplastids. Therefore the β-subunit emerges as an excellent target for compounds inhibiting parasite activity in clinical cases of co-infections. We also confirmed tha
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evolutionary comparison of prenylation pathway in kinetoplastid leishmania and its sister Leptomonas
BMC Evolutionary Biology, 2015Co-Authors: Indira Singh Chauhan, Jaspreet Kaur, Shagun Krishna, Arpita Ghosh, Prashant Singh, Mohammad Imran Siddiqi, Neeloo SinghAbstract:Leptomonas is monogenetic kinetoplastid parasite of insects and is primitive in comparison to Leishmania. Comparative studies of these two kinetoplastid may share light on the evolutionary transition to dixenous parasitism in Leishmania. In order to adapt and survive within two hosts, Leishmania species must have acquired virulence factors in addition to mechanisms that mediate susceptibility/resistance to infection in the pathology associated with disease. Rab proteins are key mediators of vesicle transport and contribute greatly to the evolution of complexity of membrane transport system. In this study we used our whole genome sequence data of these two divergent kinetoplastids to analyze the orthologues/paralogues of Rab proteins. During change of lifestyle from monogenetic (Leptomonas) to digenetic (Leishmania), we found that the prenyl machinery remained unchanged. Geranylgeranyl transferase-I (GGTase-I) was absent in both Leishmania and its sister Leptomonas. Farnesyltransferase (FTase) and geranylgeranyl transferase-II (GGTase-II) were identified for protein prenylation. We predict that activity of the missing alpha-subunit (α-subunit) of GGTase-II in Leptomonas was probably contributed by the α-subunit of FTase, while beta-subunit (β-subunit) of GGTase-II was conserved and indicated functional conservation in the evolution of these two kinetoplastids. Therefore the β-subunit emerges as an excellent target for compounds inhibiting parasite activity in clinical cases of co-infections. We also confirmed that during the evolution to digenetic life style in Leishmania, the parasite acquired capabilities to evade drug action and maintain parasite virulence in the host with the incorporation of short-chain dehydrogenase/reductase (SDR/MDR) superfamily in Rab genes. Our study based on whole genome sequences is the first to build comparative evolutionary analysis and identification of prenylation proteins in Leishmania and its sister Leptomonas. The information presented in our present work has importance for drug design targeted to kill L. donovani in humans but not affect the human form of the prenylation enzymes.
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Additional file 1: Figure S1. of Evolutionary comparison of prenylation pathway in kinetoplastid Leishmania and its sister Leptomonas
2015Co-Authors: Indira Chauhan, Jaspreet Kaur, Shagun Krishna, Arpita Ghosh, Prashant Singh, Mohammad Siddiqi, Neeloo SinghAbstract:Multiple sequence alignment of FTase (α-subunit) of Leishmania donovani (accession number XP_003862625.1, putative protein) with FTase (α-subunit) of Leishmania major (accession number XP_003722277.1, putative protein), Leishmania infantum (accession number XP_001466722.1, putative protein) and its sister Leptomonas (contig_2654, putative protein) showing conserved regions (red colored) based on percentage identity. Figure S2. Multiple sequence alignment of FTase (β-subunit) of Leishmania donovani (accession number XP_003861732.1) with FTase (β-subunit) of Leishmania major (accession number XP_001684151), Leishmania infantum (accession number XP_001470492) and its sister Leptomonas (contig_1135) showing conserved regions (red colored) based on percentage identity. Figure S3. Multiple sequence alignment of GGTase-II (α-subunit) of Leishmania donovani (accession number XM_001468149) with GGTase-II (α-subunit) of Leishmania major (accession number XM_001685808) and Leishmania infantum (accession number XP_001468186) showing conserved regions (red colored) based on percentage identity. Its sister Leptomonas has no α -subunit of GGTase-II. Figure S4. Multiple sequence alignment of GGTase-II (β-subunit) of Leishmania donovani (accession number XP_003864545) with GGTase-II (β-subunit) of Leishmania major (accession number XP_001686510) and Leishmania infantum (accession number XP_001468743) showing conserved regions (red colored) based on percentage identity. Figure S5. Alignment of various Leishmania donovani Rab protein sequences showing sequence similarities and domain conservation among them colored red based in their percentage similarity. Figure S6. Alignment of various Leptomonas Rab protein sequences showing sequence similarities and domain conservation among them colored red based in their percentage similarity. Figure S7. Phylogenetic relationship among Rab sequences of L. major, L. infantum, L. donovani and Leptomonas which is based on multiple sequence alignment (ClustalW algorithm in MEGALIGN with 1000 bootstraps). Figure S8. Circos plot was generated using Circos version 0.60, which is used to determine the similarity between Rab genes of Leishmania donovani and its sister Leptomonas. Where cyan color for all Rabs protein obtained from Leptomonas genome and green color for all Rabs protein obtained from Leishmania donovani genome. Other colors for each different Rabs. (ZIP 81526 kb
Vyacheslav Yurchenko - One of the best experts on this subject based on the ideXlab platform.
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High Prevalence and Endemism of Trypanosomatids on a Small Caribbean Island.
The Journal of eukaryotic microbiology, 2018Co-Authors: Petr Kment, Vyacheslav Yurchenko, 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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Leptomonas pyrrhocoris genomic insight into parasite s physiology
Current Genomics, 2018Co-Authors: Anzhelika Butenko, Alexander O. Frolov, Alexei Y. Kostygov, Julius Lukeš, Fred R Opperdoes, Tamara Da Silva Vieira, Rodrigo Pedro Soares, Vyacheslav YurchenkoAbstract:Background Leptomonas pyrrhocoris is a parasite of the firebug Pyrrhocoris apterus. This flagellate has been recently proposed as a model species for studying different aspects of the biology of monoxenous trypanosomatids, including host - parasite interactions. During its life cycle L. pyrrhocoris never tightly attaches to the epithelium of the insect gut. In contrast, its dixenous relatives (Leishmania spp.) establish a stable infection via attachment to the intestinal walls of their insect hosts. Material and Methods This process is mediated by chemical modifications of the cell surface lipophosphoglycans. In our study we tested whether the inability of L. pyrrhocoris to attach to the firebug's midgut is associated with the absence of these glycoconjugates. We also analyzed evolution of the proteins involved in proper lipophosphoglycan assembly, cell attachment and establishment of a stable infection in L. pyrrhocoris, L. seymouri, and Leishmania spp. Our comparative analysis demonstrated differences in SCG/L/R repertoire between the two parasite subgenera, Leishmania and Viannia, which may be related to distinct life strategies in various Leishmania spp. The genome of L. pyrrhocoris encodes 6 SCG genes, all of which are quite divergent from their orthologs in the genus Leishmania. Using direct probing with an antibody recognizing the β-Gal side chains of lipophosphoglycans, we confirmed that these structures are not synthesized in L. pyrrhocoris. Conclusion We conclude that either the SCG enzymes are not active in this species (similarly to SCG5/7 in L. major), or they possess a different biochemical activity.
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Leptomonas seymouri in leishmania infections genetic mechanisms of pre adaptation to the vertebrate host s environment
Journal of Bacteriology & Parasitology, 2015Co-Authors: Vyacheslav YurchenkoAbstract:T co-infection cases involving dixenous Leishmania spp. (mostly of the L. donovani complex) and presumably monoxenous trypanosomatids in mammalian hosts including humans are well documented. The main opportunistic parasite has been identified as Leptomonas seymouri of the sub-family Leishmaniinae. The molecular mechanisms allowing a typical parasite of insects to withstand elevated temperature and substantially different conditions of vertebrate’s tissue are not understood. Here we demonstrate that L. seymouri is well pre-adapted for the environment of the warm-blooded host. We sequenced the genome and compared the whole transcriptome profiles of this species cultivated at low (mimicking insect) and high (mimicking vertebrate host) temperatures and identified genes and pathways differentially expressed under these experimental conditions (for example, genes involved in oxidative stress response, etc). Importantly, L. seymouri can survive in sand fly insect vectors capable of transmitting Leishmania parasites, Phlebotomus argentipes and P. orientalis, although the intensity of infection compared to Leishmania is significantly lower. We concluded that although Leptomonas seymouri has a capacity to co-infect vertebrates along with Leishmania spp., additional factors are required for establishing a stable infection of this monoxenous trypanosomatid.
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Cosmopolitan distribution of a trypanosomatid Leptomonas pyrrhocoris.
Protist, 2012Co-Authors: Helena Klepetkova, Vyacheslav Yurchenko, Julius Lukeš, Aleš Horák, Dmitri A MaslovAbstract:A trypanosomatid species, designated as Typing Unit 1 (TU1) by sequences of SL RNA gene repeats, has been found in the intestine of pyrrhocorids (Insecta: Heteroptera) in Europe, Mediterranean, Central America and some parts of Asia and Africa. Phylogenetic analysis of the SL repeat sequences has shown that the isolates group in the tree according to their geographic origin. The maximal sequence divergence was observed in parasites from Neotropics suggesting the origin within and subsequent migrations from this region. The global distribution of the parasite could have been facilitated by ubiquity of its hosts that include several genera of the family Pyrrhocoridae. In Europe the TU1 flagellates frequently occur in Pyrrhocoris apterus, the host of Leptomonas pyrrhocoris Zotta, 1912 , a species that had been insufficiently defined by host and light microscopy level morphology. Herein, the Zotta's species description has been amended to include the TU1 SL RNA repeat, SSU rRNA, glycosomal GAPDH gene sequences, as well as ultrastructure. In addition, Leptomonas scantii n. sp. with an overlapping host range has been described. Moreover, 10 typing units of trypanosomatids found in the pyrrhocorid hosts demonstrate the extent of variability of trypanosomatids occurring in one host family.
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morphological discordance of the new trypanosomatid species phylogenetically associated with the genus crithidia
Protist, 2008Co-Authors: Vyacheslav Yurchenko, Julius Lukeš, Martina Tesařova, Milan Jirků, Dmitri A MaslovAbstract:Three new species of monoxenous parasites from the Neotropical Heteroptera are described on the basis of the ultrastructure of cells in culture, as well as gene sequences of Spliced Leader (SL) RNA, glyceraldehyde phosphate dehydrogenase (GAPDH) and small subunit (SSU) rRNA. The results have highlighted a striking discrepancy between the morphological (dis)similarities and the phylogenetic affinities among the insect trypanosomatids. Although each of the new species is characterized by a distinct set of morphological characters, based on the predominant promastigotes observed in culture, each of them has been provisionally assigned to the genus Leptomonas pending the future revision of this genus. Yet, instead of the phylogenetic affinity with the other members of this polyphyletic genus, the new species are most closely related to Crithidia species. Thus, the extremely long promastigotes of Leptomonas acus sp. n. and the unique morphological features found in Leptomonas bifurcata sp. n. sharply contrast with their respective relatives C. fasciculata and C. deanei both of which are typical choanomastigotes. The results clearly show that the current classification at the genus level is misleading and needs to be revised. The phylogenetic clades potentially representing the candidate new genera of monoxenous trypanosomatids have started to emerge from the presented analyses.
Anzhelika Butenko - One of the best experts on this subject based on the ideXlab platform.
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Leptomonas pyrrhocoris genomic insight into parasite s physiology
Current Genomics, 2018Co-Authors: Anzhelika Butenko, Alexander O. Frolov, Alexei Y. Kostygov, Julius Lukeš, Fred R Opperdoes, Tamara Da Silva Vieira, Rodrigo Pedro Soares, Vyacheslav YurchenkoAbstract:Background Leptomonas pyrrhocoris is a parasite of the firebug Pyrrhocoris apterus. This flagellate has been recently proposed as a model species for studying different aspects of the biology of monoxenous trypanosomatids, including host - parasite interactions. During its life cycle L. pyrrhocoris never tightly attaches to the epithelium of the insect gut. In contrast, its dixenous relatives (Leishmania spp.) establish a stable infection via attachment to the intestinal walls of their insect hosts. Material and Methods This process is mediated by chemical modifications of the cell surface lipophosphoglycans. In our study we tested whether the inability of L. pyrrhocoris to attach to the firebug's midgut is associated with the absence of these glycoconjugates. We also analyzed evolution of the proteins involved in proper lipophosphoglycan assembly, cell attachment and establishment of a stable infection in L. pyrrhocoris, L. seymouri, and Leishmania spp. Our comparative analysis demonstrated differences in SCG/L/R repertoire between the two parasite subgenera, Leishmania and Viannia, which may be related to distinct life strategies in various Leishmania spp. The genome of L. pyrrhocoris encodes 6 SCG genes, all of which are quite divergent from their orthologs in the genus Leishmania. Using direct probing with an antibody recognizing the β-Gal side chains of lipophosphoglycans, we confirmed that these structures are not synthesized in L. pyrrhocoris. Conclusion We conclude that either the SCG enzymes are not active in this species (similarly to SCG5/7 in L. major), or they possess a different biochemical activity.
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Viral discovery and diversity in trypanosomatid protozoa with a focus on relatives of the human parasite Leishmania
Proceedings of the National Academy of Sciences of the United States of America, 2017Co-Authors: Danyil Grybchuk, Natalia S. Akopyants, Aleksandras Konovalovas, Deborah E. Dobson, Haroun Zangger, Anzhelika Butenko, Alexei Y. Kostygov, Nicolas Fasel, Alexander O. FrolovAbstract:Knowledge of viral diversity is expanding greatly, but many lineages remain underexplored. We surveyed RNA viruses in 52 cultured monoxenous relatives of the human parasite Leishmania (Crithidia and Leptomonas), as well as plant-infecting Phytomonas. Leptomonas pyrrhocoris was a hotbed for viral discovery, carrying a virus (Leptomonas pyrrhocoris ostravirus 1) with a highly divergent RNA-dependent RNA polymerase missed by conventional BLAST searches, an emergent clade of tombus-like viruses, and an example of viral endogenization. A deep-branching clade of trypanosomatid narnaviruses was found, notable as Leptomonas seymouri bearing Narna-like virus 1 (LepseyNLV1) have been reported in cultures recovered from patients with visceral leishmaniasis. A deep-branching trypanosomatid viral lineage showing strong affinities to bunyaviruses was termed “Leishbunyavirus” (LBV) and judged sufficiently distinct to warrant assignment within a proposed family termed “Leishbunyaviridae.” Numerous relatives of trypanosomatid viruses were found in insect metatranscriptomic surveys, which likely arise from trypanosomatid microbiota. Despite extensive sampling we found no relatives of the totivirus Leishmaniavirus (LRV1/2), implying that it was acquired at about the same time the Leishmania became able to parasitize vertebrates. As viruses were found in over a quarter of isolates tested, many more are likely to be found in the >600 unsurveyed trypanosomatid species. Viral loss was occasionally observed in culture, providing potentially isogenic virus-free lines enabling studies probing the biological role of trypanosomatid viruses. These data shed important insights on the emergence of viruses within an important trypanosomatid clade relevant to human disease.
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ALD1 primary structure and localization.
2017Co-Authors: Aygul Ishemgulova, Anzhelika Butenko, Alexei Y. Kostygov, Natalya Kraeva, Jana Hlaváčová, Sara L. Zimmer, Lucie Podešvová, Tereza Leštinová, Julius Lukeš, Jan VotýpkaAbstract:A, Sequence alignment of the L. mexicana ALD1 protein and its orthologs found in the subfamily Leishmaniinae. All the columns containing insertions relative to the L. mexicana protein sequence are hidden and the sites of such insertions are shown with black vertical lines. The Walker motifs A (aa 113–118) and B (aa 250–260) are highlighted in grey; crucial residue in the P-loop represented by K117 of the motif A is shown in dark grey. The numbers on top correspond to the L. mexicana protein. Lmex = Leishmania mexicana; Ldon = Leishmania donovani; Linf = Leishmania infantum; Lmaj = Leishmania major; Lpyr = Leptomonas pyrrhocoris; Lsey = Leptomonas seymouri; Cfas = Crithidia fasciculata. B, Cytoplasmic localization of HA-tagged ALD1 analyzed by confocal immunofluorescence microscopy with anti-HA antibodies and Alexa Fluor 488—conjugated secondary antibodies (green). The nuclear and kinetoplast DNAs were stained with DAPI (blue), and mitochondria were stained with MitoTracker Red CMXRos (red). Scale bar is 5 μm.
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RESEARCH ARTICLE Leptomonas seymouri: Adaptations to the Dixenous Life Cycle Analyzed by Genome Sequencing, Transcriptome Profiling and Co-infection with Leishmania donovani
2016Co-Authors: Natalya Kraeva, Danyil Grybchuk, Anzhelika Butenko, Alexei Y. Kostygov, Jana Hlaváčová, Tereza Leštinová, Jan Votýpka, Jitka Myškova, Petr Volf, Pavel FlegontovAbstract:The co-infection cases involving dixenous Leishmania spp. (mostly of the L. donovani com-plex) and presumably monoxenous trypanosomatids in immunocompromised mammalian hosts including humans are well documented. The main opportunistic parasite has been identified as Leptomonas seymouri of the sub-family Leishmaniinae. The molecular mecha-nisms allowing a parasite of insects to withstand elevated temperature and substantially dif-ferent conditions of vertebrate tissues are not understood. Here we demonstrate that L. seymouri is well adapted for the environment of the warm-blooded host. We sequenced the genome and compared the whole transcriptome profiles of this species cultivated at low and high temperatures (mimicking the vector and the vertebrate host, respectively) and identified genes and pathways differentially expressed under these experimental condi-tions. Moreover, Leptomonas seymouri was found to persist for several days in two species of Phlebotomus spp. implicated in Leishmania donovani transmission. Despite of all these adaptations, L. seymouri remains a predominantly monoxenous species not capable of infecting vertebrate cells under normal conditions
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Genome of Leptomonas pyrrhocoris: a high-quality reference for monoxenous trypanosomatids and new insights into evolution of Leishmania
Scientific reports, 2016Co-Authors: Pavel Flegontov, Anzhelika Butenko, Natalya Kraeva, Sergei Firsov, Marek Eliáš, Mark C. Field, Dmitry A. Filatov, Olga Flegontova, Evgeny S. Gerasimov, Jana HlaváčováAbstract:Many high-quality genomes are available for dixenous (two hosts) trypanosomatid species of the genera Trypanosoma, Leishmania, and Phytomonas, but only fragmentary information is available for monoxenous (single-host) trypanosomatids. In trypanosomatids, monoxeny is ancestral to dixeny, thus it is anticipated that the genome sequences of the key monoxenous parasites will be instrumental for both understanding the origin of parasitism and the evolution of dixeny. Here, we present a high-quality genome for Leptomonas pyrrhocoris, which is closely related to the dixenous genus Leishmania. The L. pyrrhocoris genome (30.4 Mbp in 60 scaffolds) encodes 10,148 genes. Using the L. pyrrhocoris genome, we pinpointed genes gained in Leishmania. Among those genes, 20 genes with unknown function had expression patterns in the Leishmania mexicana life cycle suggesting their involvement in virulence. By combining differential expression data for L. mexicana, L. major and Leptomonas seymouri, we have identified several additional proteins potentially involved in virulence, including SpoU methylase and U3 small nucleolar ribonucleoprotein IMP3. The population genetics of L. pyrrhocoris was also addressed by sequencing thirteen strains of different geographic origin, allowing the identification of 1,318 genes under positive selection. This set of genes was significantly enriched in components of the cytoskeleton and the flagellum.
Julius Lukeš - One of the best experts on this subject based on the ideXlab platform.
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High Prevalence and Endemism of Trypanosomatids on a Small Caribbean Island.
The Journal of eukaryotic microbiology, 2018Co-Authors: Petr Kment, Vyacheslav Yurchenko, 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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Leptomonas pyrrhocoris genomic insight into parasite s physiology
Current Genomics, 2018Co-Authors: Anzhelika Butenko, Alexander O. Frolov, Alexei Y. Kostygov, Julius Lukeš, Fred R Opperdoes, Tamara Da Silva Vieira, Rodrigo Pedro Soares, Vyacheslav YurchenkoAbstract:Background Leptomonas pyrrhocoris is a parasite of the firebug Pyrrhocoris apterus. This flagellate has been recently proposed as a model species for studying different aspects of the biology of monoxenous trypanosomatids, including host - parasite interactions. During its life cycle L. pyrrhocoris never tightly attaches to the epithelium of the insect gut. In contrast, its dixenous relatives (Leishmania spp.) establish a stable infection via attachment to the intestinal walls of their insect hosts. Material and Methods This process is mediated by chemical modifications of the cell surface lipophosphoglycans. In our study we tested whether the inability of L. pyrrhocoris to attach to the firebug's midgut is associated with the absence of these glycoconjugates. We also analyzed evolution of the proteins involved in proper lipophosphoglycan assembly, cell attachment and establishment of a stable infection in L. pyrrhocoris, L. seymouri, and Leishmania spp. Our comparative analysis demonstrated differences in SCG/L/R repertoire between the two parasite subgenera, Leishmania and Viannia, which may be related to distinct life strategies in various Leishmania spp. The genome of L. pyrrhocoris encodes 6 SCG genes, all of which are quite divergent from their orthologs in the genus Leishmania. Using direct probing with an antibody recognizing the β-Gal side chains of lipophosphoglycans, we confirmed that these structures are not synthesized in L. pyrrhocoris. Conclusion We conclude that either the SCG enzymes are not active in this species (similarly to SCG5/7 in L. major), or they possess a different biochemical activity.
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ALD1 primary structure and localization.
2017Co-Authors: Aygul Ishemgulova, Anzhelika Butenko, Alexei Y. Kostygov, Natalya Kraeva, Jana Hlaváčová, Sara L. Zimmer, Lucie Podešvová, Tereza Leštinová, Julius Lukeš, Jan VotýpkaAbstract:A, Sequence alignment of the L. mexicana ALD1 protein and its orthologs found in the subfamily Leishmaniinae. All the columns containing insertions relative to the L. mexicana protein sequence are hidden and the sites of such insertions are shown with black vertical lines. The Walker motifs A (aa 113–118) and B (aa 250–260) are highlighted in grey; crucial residue in the P-loop represented by K117 of the motif A is shown in dark grey. The numbers on top correspond to the L. mexicana protein. Lmex = Leishmania mexicana; Ldon = Leishmania donovani; Linf = Leishmania infantum; Lmaj = Leishmania major; Lpyr = Leptomonas pyrrhocoris; Lsey = Leptomonas seymouri; Cfas = Crithidia fasciculata. B, Cytoplasmic localization of HA-tagged ALD1 analyzed by confocal immunofluorescence microscopy with anti-HA antibodies and Alexa Fluor 488—conjugated secondary antibodies (green). The nuclear and kinetoplast DNAs were stained with DAPI (blue), and mitochondria were stained with MitoTracker Red CMXRos (red). Scale bar is 5 μm.
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a novel bunyavirus like virus of trypanosomatid protist parasites
Genome Announcements, 2016Co-Authors: Natalia S. Akopyants, Deborah E. Dobson, Julius Lukeš, Lonfye Lye, Stephen M. BeverleyAbstract:ABSTRACT We report here the sequences for all three segments of a novel RNA virus (LepmorLBV1) from the insect trypanosomatid parasite Leptomonas moramango. This virus belongs to a newly discovered group of bunyavirus-like elements termed Leishbunyaviruses (LBV), the first discovered from protists related to arboviruses infecting humans.
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Cosmopolitan distribution of a trypanosomatid Leptomonas pyrrhocoris.
Protist, 2012Co-Authors: Helena Klepetkova, Vyacheslav Yurchenko, Julius Lukeš, Aleš Horák, Dmitri A MaslovAbstract:A trypanosomatid species, designated as Typing Unit 1 (TU1) by sequences of SL RNA gene repeats, has been found in the intestine of pyrrhocorids (Insecta: Heteroptera) in Europe, Mediterranean, Central America and some parts of Asia and Africa. Phylogenetic analysis of the SL repeat sequences has shown that the isolates group in the tree according to their geographic origin. The maximal sequence divergence was observed in parasites from Neotropics suggesting the origin within and subsequent migrations from this region. The global distribution of the parasite could have been facilitated by ubiquity of its hosts that include several genera of the family Pyrrhocoridae. In Europe the TU1 flagellates frequently occur in Pyrrhocoris apterus, the host of Leptomonas pyrrhocoris Zotta, 1912 , a species that had been insufficiently defined by host and light microscopy level morphology. Herein, the Zotta's species description has been amended to include the TU1 SL RNA repeat, SSU rRNA, glycosomal GAPDH gene sequences, as well as ultrastructure. In addition, Leptomonas scantii n. sp. with an overlapping host range has been described. Moreover, 10 typing units of trypanosomatids found in the pyrrhocorid hosts demonstrate the extent of variability of trypanosomatids occurring in one host family.