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1.
J Med Entomol ; 59(5): 1847-1852, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-35900064

RESUMO

Present work aimed to identify blood feeding sources and attempt to detect Leishmania DNA in Nyssomyia antunesi, suspected vector of Leishmania sp., from a park in the urban center of Belém, the capital of Pará State, in the Brazilian Amazon. Entire bodies and gut contents of Ny. antunesi engorged females, previously captured in the urban park with Centers for Disease Control (CDC) light traps and aspiration on tree bases, were subjected to Leishmania and vertebrate DNA detection through amplification of the Leishmania mini-exon and vertebrate cytochrome b (cyt b) gene regions, respectively. The quality of DNA extraction from entire bodies was ensured through amplification of the dipteran cyt b region. The vertebrate cyt b amplicons were sequenced and compared with those available on GenBank. A maximum likelihood phylogenetic tree was constructed to assess the clustering patterns of these sequences. Leishmania DNA was not detected. The sequences of 13 vertebrate cyt b amplicons were considered informative, exhibiting similarity and clustering with the following six vertebrate species: Dasyprocta leporina (1), Cuniculus paca (1), Tamandua tetradactyla (4), Choloepus didactylus (4), Pteroglossus aracari aracari (2), Homo sapiens (1). The samples of D. leporina and C. paca were obtained from the CDC canopy, whereas the others were by aspiration from tree bases. The present results revealed the eclectic and opportunist blood-feeding behavior of Ny. antunesi, with birds and mammals, these last ones acting as potential reservoirs for Leishmania species, distributed throughout the vertical forest strata.


Assuntos
Kinetoplastida , Leishmania , Psychodidae , Animais , Brasil , Citocromos b/genética , Feminino , Insetos Vetores , Leishmania/genética , Mamíferos , Filogenia
2.
Parasit Vectors ; 15(1): 239, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35773725

RESUMO

BACKGROUND: Rhodnius robustus and Rhodnius pictipes are vectors of Trypanosoma cruzi, the etiologic agent of Chagas disease (CD), that are found in the Brazilian Amazon region. Susceptibility to infection and vector competence depend on the parasite-vector relationship. Our objective was to evaluate the interaction between T. cruzi and these two triatomine vectors in pure and mixed experimental infections of T. cruzi strains from the same or different geographic regions. METHODS: Fifth-instar nymphs of R. robustus and R. pictipes were fed on mice infected with four T. cruzi strains, namely genotypes TcIAM, TcIMG, TcIIPR, and TcIVAM, respectively, from the Brazilian states of Amazonas, Minas Gerais and Paraná. Over a period of 120 days, excreta were examined every 20 days to assess vector competence, and intestinal contents (IC) were examined every 30 days to determine susceptibility to infection. RESULTS: The highest positive rate in the fresh examination (%+FE, 30.0%), the highest number of parasitic forms (PF, n = 1969) and the highest metacyclogenesis rate (%MC, 53.8%) in the excreta were recorded for R. robustus/TcIVAM. Examination of the IC of R. pictipes revealed a higher number of PF in infections with TcIAM (22,680 PF) and TcIIPR (19,845 PF) alone or in association (17,145 PF), as well as a %+FE of 75.0% with TcII, in comparison with the other genotypes. The highest %MC (100%) was recorded for the mixed infections of TcIAM with TcIIPR or TcIVAM in the IC of R. pictipes. CONCLUSIONS: Overall, both species were found to be susceptible to the T. cruzi strains studied. Rhodnius robustus showed vector competence for genotypes TcIVAM and TcIAM+TcIVAM and R. pictipes for TcIAM+TcIVAM and TcIAM+TcIIPR; there was elimination of infective forms as early as at 20 days. Our results suggest that both the genetics of the parasite and its geographic origin influence the susceptibility to infection and vector competence, alone or in association.


Assuntos
Doença de Chagas , Kinetoplastida , Rhodnius , Triatominae , Trypanosoma cruzi , Trypanosomatina , Animais , Doença de Chagas/parasitologia , Camundongos , Rhodnius/parasitologia , Triatominae/parasitologia , Trypanosoma cruzi/genética
3.
Protist ; 173(4): 125885, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35667307

RESUMO

Kinetoplastids represent a stockpile of undiscovered protist diversity. Free-living members of this group have been studied less intensively compared to their important parasitic relatives. We have isolated a new soil-dwelling bacteriotrophic kinetoplastid, which is described here as a new genus and new species, Avlakibodo gracilis gen. et sp. nov. Phylogenetic analysis of 18S rRNA genes showed highly supported sister relationship of this protist with the clade uniting Neobodo borokensis, Neobodo curvifilus, Neobodo saliens, Actuariola framvarensis, some Neobodo designis isolates and several environmental sequences, with high statistical support. We have reconstructed the organization of the microtubular cytoskeleton of A. gracilis and determined the origins of the main bands of microtubules. Characteristic ultrastructural features include cytostome associated microtubules (FAS), cytopharynx associated additional microtubules (CMT), microtubular prism (nemadesm) and three microtubular roots (R1, R2 and R3).


Assuntos
Kinetoplastida , Solo , Eucariotos , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA
4.
Front Cell Infect Microbiol ; 12: 894213, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35601102

RESUMO

Proximity labelling is a powerful and rapidly developing technology for exploring the interaction space and molecular environment of a protein of interest at the nanometre scale. In proximity labelling, a promiscuous biotinylating enzyme is genetically fused to the protein of interest, initiation of labelling then results in the biotinylating enzyme generating reactive biotin which covalently 'tags' nearby molecules. Importantly, this labelling takes place in vivo whilst the protein of interest continues to perform its normal functions in the cell. Due to its unique advantageous characteristics, proximity labelling is driving discoveries in an ever increasing range of organisms. Here, we highlight the applications of proximity labelling to the study of kinetoplastids, a group of eukaryotic protozoa that includes trypanosomes and Leishmania which can cause serious disease in humans and livestock. We first provide a general overview of the proximity labelling experimental workflow including key labelling enzymes used, proper experimental design with appropriate controls and robust statistical analysis to maximise the amount of reliable spatial information that is generated. We discuss studies employing proximity labelling in kinetoplastid parasites to illustrate how these key principles of experimental design are applied. Finally, we highlight emerging trends in the development of proximity labelling methodology.


Assuntos
Kinetoplastida , Parasitos , Animais , Biotina/metabolismo , Biotinilação , Humanos , Kinetoplastida/metabolismo , Parasitos/metabolismo
5.
Zoonoses Public Health ; 69(2): 95-105, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34713588

RESUMO

This research analysed the spatiotemporal distribution of triatomines infected by trypanosomatid parasites in an endemic region for Chagas disease, in the state of Pernambuco, Northeastern Brazil. The database included the total number of triatomines captured from intradomicile and peridomicile areas, as well as the infection rate (IR) by trypanosomatid. The G i ∗ by Getis-Ord method was used to statistically identify significant concentration clusters and the IR of triatomines by trypanosomatids. A generalized linear regression model with a binomial distribution was used to evaluate the probability of finding an IR by trypanosomatids. Overall, of 4,800 triatomines examined, trypanosomatid forms similar to Trypanosoma cruzi were detected in 10.29% of them, and the majority of positive specimens (98.17%) were collected at intradomicile. The geospatial analyses identified triatomines clusters in intradomicile and peridomicile environments. According to the logistic regression data for species (Panstrongylus lutzi, P. megistus, Triatoma brasiliensis and T. pseudomaculata), the probability of detection of T. cruzi infection remains constant in up to 50 specimens examined or more. The findings of this research revealed a scenario never studied in this area through this type of spatiotemporal analysis, which is essential to identify areas of vulnerability for the occurrence of these vectors and consequently for Chagas disease.


Assuntos
Doença de Chagas , Kinetoplastida , Triatominae , Trypanosoma cruzi , Trypanosomatina , Animais , Brasil/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Insetos Vetores/parasitologia
6.
Open Biol ; 11(9): 210131, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34465213

RESUMO

Expansion microscopy (ExM) has become a powerful super-resolution method in cell biology. It is a simple, yet robust approach, which does not require any instrumentation or reagents beyond those present in a standard microscopy facility. In this study, we used kinetoplastid parasites Trypanosoma brucei and Leishmania major, which possess a complex, yet well-defined microtubule-based cytoskeleton, to demonstrate that this method recapitulates faithfully morphology of structures as previously revealed by a combination of sophisticated electron microscopy (EM) approaches. Importantly, we also show that due to the rapidness of image acquisition and three-dimensional reconstruction of cellular volumes ExM is capable of complementing EM approaches by providing more quantitative data. This is demonstrated on examples of less well-appreciated microtubule structures, such as the neck microtubule of T. brucei or the pocket, cytosolic and multivesicular tubule-associated microtubules of L. major. We further demonstrate that ExM enables identifying cell types rare in a population, such as cells in mitosis and cytokinesis. Three-dimensional reconstruction of an entire volume of these cells provided details on the morphology of the mitotic spindle and the cleavage furrow. Finally, we show that established antibody markers of major cytoskeletal structures function well in ExM, which together with the ability to visualize proteins tagged with small epitope tags will facilitate studies of the kinetoplastid cytoskeleton.


Assuntos
Cinetocoros/metabolismo , Kinetoplastida/metabolismo , Leishmania major/metabolismo , Microscopia Eletrônica/métodos , Microtúbulos/metabolismo , Proteínas de Protozoários/metabolismo , Trypanosoma brucei brucei/metabolismo , Cinetocoros/ultraestrutura , Kinetoplastida/ultraestrutura , Leishmania major/ultraestrutura , Microtúbulos/ultraestrutura , Trypanosoma brucei brucei/ultraestrutura
7.
RNA Biol ; 18(sup1): 139-147, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34308760

RESUMO

The ribonucleoprotein RNase MRP is responsible for the processing of ribosomal RNA precursors. It is found in virtually all eukaryotes that have been examined. In the Euglenozoa, including the genera Euglena, Diplonema and kinetoplastids, MRP RNA and protein subunits have so far escaped detection using bioinformatic methods. However, we now demonstrate that the RNA component is widespread among the Euglenozoa and that these RNAs have secondary structures that conform to the structure of all other phylogenetic groups. In Euglena, we identified the same set of P/MRP protein subunits as in many other protists. However, we failed to identify any of these proteins in the kinetoplastids. This finding poses interesting questions regarding the structure and function of RNase MRP in these species.


Assuntos
DNA de Cinetoplasto/metabolismo , Endorribonucleases/metabolismo , Euglena/enzimologia , Conformação de Ácido Nucleico , Proteínas de Protozoários/metabolismo , Processamento Pós-Transcricional do RNA , RNA de Protozoário/metabolismo , Pareamento de Bases , Sequência de Bases , DNA de Cinetoplasto/química , DNA de Cinetoplasto/genética , Endorribonucleases/química , Endorribonucleases/genética , Euglena/genética , Euglena/crescimento & desenvolvimento , Kinetoplastida/enzimologia , Kinetoplastida/genética , Kinetoplastida/crescimento & desenvolvimento , Filogenia , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , RNA de Protozoário/química , RNA de Protozoário/genética
8.
BMC Ecol Evol ; 21(1): 131, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162332

RESUMO

BACKGROUND: ApaH like phosphatases (ALPHs) originate from the bacterial ApaH protein and have been identified in all eukaryotic super-groups. Only two of these proteins have been functionally characterised. We have shown that the ApaH like phosphatase ALPH1 from the Kinetoplastid Trypanosoma brucei is the mRNA decapping enzyme of the parasite. In eukaryotes, Dcp2 is the major mRNA decapping enzyme and mRNA decapping by ALPHs is unprecedented, but the bacterial ApaH protein was recently found decapping non-conventional caps of bacterial mRNAs. These findings prompted us to explore whether mRNA decapping by ALPHs is restricted to Kinetoplastida or could be more widespread among eukaryotes. RESULTS: We screened 827 eukaryotic proteomes with a newly developed Python-based algorithm for the presence of ALPHs and used the data to characterize the phylogenetic distribution, conserved features, additional domains and predicted intracellular localisation of this protein family. For most organisms, we found ALPH proteins to be either absent (495/827 organisms) or to have non-cytoplasmic localisation predictions (73% of all ALPHs), excluding a function in mRNA decapping. Although, non-cytoplasmic ALPH proteins had in vitro mRNA decapping activity. Only 71 non-Kinetoplastida have ALPH proteins with predicted cytoplasmic localisations. However, in contrast to Kinetoplastida, these organisms also possess a homologue of Dcp2 and in contrast to ALPH1 of Kinetoplastida, these ALPH proteins are very short and consist of the catalytic domain only. CONCLUSIONS: ALPH was present in the last common ancestor of eukaryotes, but most eukaryotes have either lost the enzyme, or use it exclusively outside the cytoplasm. The acceptance of mRNA as a substrate indicates that ALPHs, like bacterial ApaH, have a wide substrate range: the need to protect mRNAs from unregulated degradation is one possible explanation for the selection against the presence of cytoplasmic ALPH proteins in most eukaryotes. Kinetoplastida succeeded to exploit ALPH as their only or major mRNA decapping enzyme. 71 eukaryotic organisms outside the Kinetoplastid lineage have short ALPH proteins with cytoplasmic localisation predictions: whether these proteins are used as decapping enzymes in addition to Dcp2 or else have adapted to not accept mRNAs as a substrate, remains to be explored.


Assuntos
Eucariotos , Kinetoplastida , Endorribonucleases/genética , Kinetoplastida/genética , Monoéster Fosfórico Hidrolases , Filogenia , RNA Mensageiro/genética
9.
PLoS One ; 16(5): e0251133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33956864

RESUMO

DNA transposons are defined as repeated DNA sequences that can move within the host genome through the action of transposases. The transposon superfamily Merlin was originally found mainly in animal genomes. Here, we describe a global distribution of the Merlin in animals, fungi, plants and protists, reporting for the first time their presence in Rhodophyceae, Metamonada, Discoba and Alveolata. We identified a great variety of potentially active Merlin families, some containing highly imperfect terminal inverted repeats and internal tandem repeats. Merlin-related sequences with no evidence of mobilization capacity were also observed and may be products of domestication. The evolutionary trees support that Merlin is likely an ancient superfamily, with early events of diversification and secondary losses, although repeated re-invasions probably occurred in some groups, which would explain its diversity and discontinuous distribution. We cannot rule out the possibility that the Merlin superfamily is the product of multiple horizontal transfers of related prokaryotic insertion sequences. Moreover, this is the first account of a DNA transposon in kinetoplastid flagellates, with conserved Merlin transposase identified in Bodo saltans and Perkinsela sp., whereas it is absent in trypanosomatids. Based on the level of conservation of the transposase and overlaps of putative open reading frames with Merlin, we propose that in protists it may serve as a raw material for gene emergence.


Assuntos
Elementos de DNA Transponíveis/genética , Eucariotos/genética , Kinetoplastida/genética , Neurofibromina 2/genética , Alveolados/genética , Evolução Molecular , Filogenia , Reação em Cadeia da Polimerase
10.
Commun Biol ; 4(1): 501, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33893386

RESUMO

Heterotrophic protists (unicellular eukaryotes) form a major link from bacteria and algae to higher trophic levels in the sunlit ocean. Their role on the deep seafloor, however, is only fragmentarily understood, despite their potential key function for global carbon cycling. Using the approach of combined DNA metabarcoding and cultivation-based surveys of 11 deep-sea regions, we show that protist communities, mostly overlooked in current deep-sea foodweb models, are highly specific, locally diverse and have little overlap to pelagic communities. Besides traditionally considered foraminiferans, tiny protists including diplonemids, kinetoplastids and ciliates were genetically highly diverse considerably exceeding the diversity of metazoans. Deep-sea protists, including many parasitic species, represent thus one of the most diverse biodiversity compartments of the Earth system, forming an essential link to metazoans.


Assuntos
Biodiversidade , Cilióforos/isolamento & purificação , Euglenozoários/isolamento & purificação , Foraminíferos/isolamento & purificação , Kinetoplastida/isolamento & purificação , Oceano Atlântico , Sedimentos Geológicos , Oceano Pacífico
11.
Fish Shellfish Immunol ; 114: 58-64, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33864945

RESUMO

Kinetoplastid parasites require transferrin (Tf), being the main source of iron, for growth and multiplication. This group of parasites developed a unique receptor-mediated system for acquiring host Tf which bears no structural homology with the host transferrin receptor. Trypanoplasma borreli, a blood parasite of common carp, probably uses a similar mechanism to sequester iron from host transferrin. In this study, we demonstrate a critical role of Tf for parasite growth. For in vitro studies we isolated and purified Tf from carp homozygous for the D or G allele of Tf. We obtained Tf-depleted serum using specific antibodies to carp Tf and studied gene expression in vivo during T. borreli infection with Real Time-quantitative PCR. We demonstrate that T. borreli cannot survive in medium supplemented with Tf-depleted serum while reconstitution with Tf restores normal growth. The critical role of Tf for parasite survival was shown in incomplete medium (medium without serum): addition of purified Tf significantly increased parasite survival. We also demonstrate that Tf polymorphism has a significant impact on T. borreli multiplication. Cultured parasites die more quickly in an environment containing D-typed Tf, as compared to medium with G-typed Tf. Gene expression during T. borreli infection in carp did not show an acute phase response. We could, however, observe an increased transcription of Tf in the head kidney, which may be associated with an immunological function of the Tf protein.


Assuntos
Carpas/sangue , Kinetoplastida/efeitos dos fármacos , Kinetoplastida/crescimento & desenvolvimento , Transferrina/genética , Animais , Carpas/genética , Meios de Cultura
12.
Int J Mol Sci ; 22(9)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33925823

RESUMO

The development of novel anti-infectives against Kinetoplastids pathogens targeting proteins is a big problem occasioned by the antigenic variation in these parasites. This is also a global concern due to the zoonosis of these parasites, as they infect both humans and animals. Therefore, we need not only to create novel antibiotics, but also to speed up the development pipeline for these antibiotics. This may be achieved by using novel drug targets for Kinetoplastids drug discovery. In this study, we focused our attention on motifs of rRNA molecules that have been created using homology modeling. The RNA is the most ambiguous biopolymer in the kinetoplatid, which carries many different functions. For instance, tRNAs, rRNAs, and mRNAs are essential for gene expression both in the pro-and eukaryotes. However, all these types of RNAs have sequences with unique 3D structures that are specific for kinetoplastids only and can be used to shut down essential biochemical processes in kinetoplastids only. All these features make RNA very potent targets for antibacterial drug development. Here, we combine in silico methods combined with both computational biology and structure prediction tools to address our hypothesis. In this study, we outline a systematic approach for identifying kinetoplastid rRNA-ligand interactions and, more specifically, techniques that can be used to identify small molecules that target particular RNA. The high-resolution optimized model structures of these kineoplastids were generated using RNA 123, where all the stereochemical conflicts were solved and energies minimized to attain the best biological qualities. The high-resolution optimized model's structures of these kinetoplastids were generated using RNA 123 where all the stereochemical conflicts were solved and energies minimized to attain the best biological qualities. These models were further analyzed to give their docking assessment reliability. Docking strategies, virtual screening, and fishing approaches successfully recognized novel and myriad macromolecular targets for the myxobacterial natural products with high binding affinities to exploit the unmet therapeutic needs. We demonstrate a sensible exploitation of virtual screening strategies to 18S rRNA using natural products interfaced with classical maximization of their efficacy in phamacognosy strategies that are well established. Integration of these virtual screening strategies in natural products chemistry and biochemistry research will spur the development of potential interventions to these tropical neglected diseases.


Assuntos
Produtos Biológicos/química , Kinetoplastida/genética , RNA Ribossômico 18S/química , Animais , Doença de Chagas/tratamento farmacológico , Biologia Computacional/métodos , Descoberta de Drogas/métodos , Genes de Protozoários , Humanos , Kinetoplastida/metabolismo , Kinetoplastida/patogenicidade , Leishmaniose/tratamento farmacológico , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mapeamento de Interação de Proteínas , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , RNA Ribossômico/química , RNA Ribossômico/metabolismo , RNA Ribossômico 18S/metabolismo , Tripanossomíase/tratamento farmacológico
13.
Parasitology ; 148(10): 1223-1236, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33678213

RESUMO

Kinetoplastid parasites are responsible for both human and animal diseases across the globe where they have a great impact on health and economic well-being. Many species and life cycle stages are difficult to study due to limitations in isolation and culture, as well as to their existence as heterogeneous populations in hosts and vectors. Single-cell transcriptomics (scRNA-seq) has the capacity to overcome many of these difficulties, and can be leveraged to disentangle heterogeneous populations, highlight genes crucial for propagation through the life cycle, and enable detailed analysis of host­parasite interactions. Here, we provide a review of studies that have applied scRNA-seq to protozoan parasites so far. In addition, we provide an overview of sample preparation and technology choice considerations when planning scRNA-seq experiments, as well as challenges faced when analysing the large amounts of data generated. Finally, we highlight areas of kinetoplastid research that could benefit from scRNA-seq technologies.


Assuntos
Perfilação da Expressão Gênica , Kinetoplastida/genética , Análise de Célula Única , Interações Hospedeiro-Parasita , RNA-Seq
14.
PLoS One ; 16(3): e0248244, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33684147

RESUMO

Rodents are reservoirs of numerous zoonotic diseases caused by bacteria, protozoans, or viruses. In Gabon, the circulation and maintenance of rodent-borne zoonotic infectious agents are poorly studied and are often limited to one type of pathogen. Among the three existing studies on this topic, two are focused on a zoonotic virus, and the third is focused on rodent Plasmodium. In this study, we searched for a wide range of bacteria, protozoa and viruses in different organs of rodents from the town of Franceville in Gabon. Samples from one hundred and ninety-eight (198) small mammals captured, including two invasive rodent species, five native rodent species and 19 shrews belonging to the Soricidae family, were screened. The investigated pathogens were bacteria from the Rickettsiaceae and Anaplasmataceae families, Mycoplasma spp., Bartonella spp., Borrelia spp., Orientia spp., Occidentia spp., Leptospira spp., Streptobacillus moniliformis, Coxiella burnetii, and Yersinia pestis; parasites from class Kinetoplastida spp. (Leishmania spp., Trypanosoma spp.), Piroplasmidae spp., and Toxoplasma gondii; and viruses from Paramyxoviridae, Hantaviridae, Flaviviridae and Mammarenavirus spp. We identified the following pathogenic bacteria: Anaplasma spp. (8.1%; 16/198), Bartonella spp. (6.6%; 13/198), Coxiella spp. (5.1%; 10/198) and Leptospira spp. (3.5%; 7/198); and protozoans: Piroplasma sp. (1%; 2/198), Toxoplasma gondii (0.5%; 1/198), and Trypanosoma sp. (7%; 14/198). None of the targeted viral genes were detected. These pathogens were found in Gabonese rodents, mainly Lophuromys sp., Lemniscomys striatus and Praomys sp. We also identified new genotypes: Candidatus Bartonella gabonensis and Uncultured Anaplasma spp. This study shows that rodents in Gabon harbor some human pathogenic bacteria and protozoans. It is necessary to determine whether the identified microorganisms are capable of undergoing zoonotic transmission from rodents to humans and if they may be responsible for human cases of febrile disease of unknown etiology in Gabon.


Assuntos
Bactérias , Reservatórios de Doenças , Kinetoplastida , Roedores , Musaranhos , Toxoplasma , Vírus , Zoonoses , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Cidades , Gabão/epidemiologia , Humanos , Kinetoplastida/classificação , Kinetoplastida/isolamento & purificação , Roedores/microbiologia , Roedores/parasitologia , Roedores/virologia , Musaranhos/microbiologia , Musaranhos/parasitologia , Musaranhos/virologia , Toxoplasma/classificação , Toxoplasma/isolamento & purificação , Vírus/classificação , Vírus/isolamento & purificação , Zoonoses/microbiologia , Zoonoses/parasitologia , Zoonoses/virologia
15.
Acta Parasitol ; 66(3): 1055-1058, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33554301

RESUMO

PURPOSE: Mexico is considered endemic for Leishmania; recent reports indicate autochthonous human and canine leishmaniasis caused by Leishmania mexicana in Sinaloa state. Lutzomyia sand fly are the primary vector of the parasite, although no records of phlebotomine vectors of Leishmania exist from Sinaloa. Other hematophagous dipterans, like Culicoides, could represent possible vectors of Leishmania in absence of phlebotomines. The known distribution of Culicoides includes the southern portion of Sinaloa state, in northwestern Mexico, with records of Culicoides furens. However, no studies have demonstrated the presence of Leishmania in C. furens or its possible participation in the parasite's life cycle in Mexico. This study, therefore, sought to detect DNA of Leishmania in C. furens captured in an endemic area of autochthonous canine leishmaniasis in northwestern Mexico. METHODS: Culicoides were captured with CDC light traps, identified morphologically, and organized in pools. DNA was extracted, and used to amplify the ribosomal ITS1 region of Leishmania. PCR products were digested with HaeIII endonuclease; the banding patterns obtained were compared to reference strains. RESULTS: Leishmania mexicana DNA was detected in five out of nine pools (55%) of female C. furens. CONCLUSION: This study offers the first evidence of L. mexicana DNA in C. furens, in an endemic area of canine leishmaniasis in northwestern Mexico, where no evidence exists of the presence of phlebotomine sand fly.


Assuntos
Ceratopogonidae , Kinetoplastida , Leishmania , Leishmaniose Cutânea , Leishmaniose , Animais , DNA , Cães , Feminino , Humanos , Insetos Vetores , México/epidemiologia
16.
Sci Rep ; 11(1): 2946, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536456

RESUMO

Kinetoplastids are heterotrophic flagellated protists, including important parasites of humans and animals (trypanosomatids), and ecologically important free-living bacterial consumers (bodonids). Phylogenies have shown that the earliest-branching kinetoplastids are all parasites or obligate endosymbionts, whose highly-derived state makes reconstructing the ancestral state of the group challenging. We have isolated new strains of unusual free-living flagellates that molecular phylogeny shows to be most closely related to endosymbiotic and parasitic Perkinsela and Ichthyobodo species that, together with unidentified environmental sequences, form the clade at the base of kinetoplastids. These strains are therefore the first described free-living prokinetoplastids, and potentially very informative in understanding the evolution and ancestral states of morphological and molecular characteristics described in other kinetoplastids. Overall, we find that these organisms morphologically and ultrastructurally resemble some free-living bodonids and diplonemids, and possess nuclear genomes with few introns, polycistronic mRNA expression, high coding density, and derived traits shared with other kinetoplastids. Their genetic repertoires are more diverse than the best-studied free-living kinetoplastids, which is likely a reflection of their higher metabolic potential. Mitochondrial RNAs of these new species undergo the most extensive U insertion/deletion editing reported so far, and limited deaminative C-to-U and A-to-I editing, but we find no evidence for mitochondrial trans-splicing.


Assuntos
Núcleo Celular/genética , Genoma Mitocondrial , Kinetoplastida/genética , Evolução Biológica , Kinetoplastida/citologia , Filogenia
17.
Biochem Soc Trans ; 49(1): 29-39, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33439256

RESUMO

Kinetoplastid parasites have essential organelles called glycosomes that are analogous to peroxisomes present in other eukaryotes. While many of the processes that regulate glycosomes are conserved, there are several unique aspects of their biology that are divergent from other systems and may be leveraged as therapeutic targets for the treatment of kinetoplastid diseases. Glycosomes are heterogeneous organelles that likely exist as sub-populations with different protein composition and function in a given cell, between individual cells, and between species. However, the limitations posed by the small size of these organelles makes the study of this heterogeneity difficult. Recent advances in the analysis of small vesicles by flow-cytometry provide an opportunity to overcome these limitations. In this review, we describe studies that document the diverse nature of glycosomes and propose an approach to using flow cytometry and organelle sorting to study the diverse composition and function of these organelles. Because the cellular machinery that regulates glycosome protein import and biogenesis is likely to contribute, at least in part, to glycosome heterogeneity we highlight some ways in which the glycosome protein import machinery differs from that of peroxisomes in other eukaryotes.


Assuntos
Kinetoplastida/citologia , Microcorpos/fisiologia , Animais , Kinetoplastida/genética , Kinetoplastida/metabolismo , Kinetoplastida/ultraestrutura , Microcorpos/metabolismo , Peroxissomos/metabolismo , Transporte Proteico , Proteínas de Protozoários/metabolismo
18.
ISME J ; 15(6): 1680-1694, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33452479

RESUMO

Bacterial endosymbiosis has been instrumental in eukaryotic evolution, and includes both mutualistic, dependent and parasitic associations. Here we characterize an intracellular bacterium inhabiting the flagellated protist Bodo saltans (Kinetoplastida). We present a complete bacterial genome comprising a 1.39 Mb circular chromosome with 40.6% GC content. Fluorescent in situ hybridisation confirms that the endosymbiont is located adjacent to the nuclear membrane, and a detailed model of its intracellular niche is generated using serial block-face scanning electron microscopy. Phylogenomic analysis shows that the endosymbiont belongs to the Holosporales, most closely related to other α-proteobacterial endosymbionts of ciliates and amoebae. Comparative genomics indicates that it has a limited metabolism and is nutritionally host-dependent. However, the endosymbiont genome does encode diverse symbiont-specific secretory proteins, including a type VI secretion system and three separate toxin-antitoxin systems. We show that these systems are actively transcribed and hypothesize they represent a mechanism by which B. saltans becomes addicted to its endosymbiont. Consistent with this idea, attempts to cure Bodo of endosymbionts led to rapid and uniform cell death. This study adds kinetoplastid flagellates to ciliates and amoebae as hosts of Paracaedibacter-like bacteria, suggesting that these antagonistic endosymbioses became established very early in Eukaryotic evolution.


Assuntos
Alphaproteobacteria , Kinetoplastida , Sistemas Toxina-Antitoxina , Eucariotos , Filogenia , Simbiose
19.
Genome Biol Evol ; 13(2)2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33432342

RESUMO

Mitochondria retain their own genomes as other bacterial endosymbiont-derived organelles. Nevertheless, no protein for DNA replication and repair is encoded in any mitochondrial genomes (mtDNAs) assessed to date, suggesting that the nucleus primarily governs the maintenance of mtDNA. As the proteins of diverse evolutionary origins occupy a large proportion of the current mitochondrial proteomes, we anticipate finding the same evolutionary trend in the nucleus-encoded machinery for mtDNA maintenance. Indeed, none of the DNA polymerases (DNAPs) in the mitochondrial endosymbiont, a putative α-proteobacterium, seemingly had been inherited by their descendants (mitochondria), as none of the known types of mitochondrion-localized DNAP showed a specific affinity to the α-proteobacterial DNAPs. Nevertheless, we currently have no concrete idea of how and when the known types of mitochondrion-localized DNAPs emerged. We here explored the origins of mitochondrion-localized DNAPs after the improvement of the samplings of DNAPs from bacteria and phages/viruses. Past studies have revealed that a set of mitochondrion-localized DNAPs in kinetoplastids and diplonemids, namely PolIB, PolIC, PolID, PolI-Perk1/2, and PolI-dipl (henceforth designated collectively as "PolIBCD+") have emerged from a single DNAP. In this study, we recovered an intimate connection between PolIBCD+ and the DNAPs found in a particular group of phages. Thus, the common ancestor of kinetoplastids and diplonemids most likely converted a laterally acquired phage DNAP into a mitochondrion-localized DNAP that was ancestral to PolIBCD+. The phage origin of PolIBCD+ hints at a potentially large contribution of proteins acquired via nonvertical processes to the machinery for mtDNA maintenance in kinetoplastids and diplonemids.


Assuntos
Bacteriófagos/genética , DNA Polimerase Dirigida por DNA/genética , Euglenozoários/genética , Transferência Genética Horizontal , Kinetoplastida/genética , Bacteriófagos/enzimologia , DNA Polimerase Dirigida por DNA/classificação , Euglenozoários/enzimologia , Kinetoplastida/enzimologia , Mitocôndrias/enzimologia , Mitocôndrias/genética , Filogenia
20.
Trends Genet ; 37(1): 21-34, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32993968

RESUMO

The genomes of all organisms are read throughout their growth and development, generating new copies during cell division and encoding the cellular activities dictated by the genome's content. However, genomes are not invariant information stores but are purposefully altered in minor and major ways, adapting cellular behaviour and driving evolution. Kinetoplastids are eukaryotic microbes that display a wide range of such read-write genome activities, in many cases affecting critical aspects of their biology, such as host adaptation. Here we discuss the range of read-write genome changes found in two well-studied kinetoplastid parasites, Trypanosoma brucei and Leishmania, focusing on recent work that suggests such adaptive genome variation is linked to novel strategies the parasites use to replicate their unconventional genomes.


Assuntos
Replicação do DNA , DNA de Cinetoplasto/genética , Genoma de Protozoário , Kinetoplastida/genética , Leishmania/genética , Trypanosoma brucei brucei/genética , Animais
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