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1.
Int J Mol Sci ; 23(14)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35886895

RESUMO

Isothermal amplification of nucleic acids has the potential to be applied in resource-limited areas for the detection of infectious agents, as it does not require complex nucleic purification steps or specific and expensive equipment and reagents to perform the reaction and read the result. Since human and animal infections by pathogens of the Tryponasomatidae family occur mainly in resource-limited areas with scant health infrastructures and personnel, detecting infections by these methodologies would hold great promise. Here, we conduct a narrative review of the literature on the application of isothermal nucleic acid amplification for Trypanosoma and Leishmania infections, which are a scourge for human health and food security. We highlight gaps and propose ways to improve them to translate these powerful technologies into real-world field applications for neglected human and animal diseases caused by Trypanosomatidae.


Assuntos
Leishmaniose , Ácidos Nucleicos , Parasitos , Trypanosomatina , Animais , Humanos , Leishmaniose/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/métodos , Ácidos Nucleicos/genética
2.
Front Cell Infect Microbiol ; 12: 851903, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795183

RESUMO

Parasites are important components of the immense n-dimensional trophic network that connects all living beings because they, among others, forge biodiversity and deeply influence ecological evolution and host behavior. In this sense, the influence of Trypanosomatidae remains unknown. The aim of this study was to determine trypanosomatid infection and richness in rats, opossums, and dogs in the semiarid Caatinga biome. We submitted DNA samples from trypanosomatids obtained through axenic cultures of the blood of these mammals to mini exon multiplex-PCR, Sanger, and next-generation sequencing targeting the 18S rDNA gene. Phylogenetic analyses were performed to identify genetic diversity in the Trypanosomatidae family. Shannon, Simpson, equability, and beta-diversity indices were calculated per location and per mammalian host. Dogs were surveyed for trypanosomatid infection through hemocultures and serological assays. The examined mammal species of this area of the Caatinga biome exhibited an enormous trypanosomatid species/genotypes richness. Ten denoised Operational Taxonomic Units (ZOTUs), including three species (Trypanosoma cruzi, Trypanosoma rangeli and Crithidia mellificae) and one Trypanosoma sp. five genotypes/lineages (T. cruzi DTU TcI, TcII, and TcIV; T. rangeli A and B) and four DTU TcI haplotypes (ZOTU1, ZOTU2, ZOTU5, and ZOTU10 merged), as well as 13 Amplicon Sequence Variants (ASVs), including five species (T. cruzi, T. rangeli, C. mellificae, Trypanosoma dionisii, and Trypanosoma lainsoni), five genotypes/lineages (same as the ZOTUs) and six DTU TcI haplotypes (ASV, ASV1, ASV2, ASV3, ASV5 and ASV13), were identified in single and mixed infections. We observed that trypanosomatids present a broad host spectrum given that species related to a single host are found in other mammals from different taxa. Concomitant infections between trypanosomatids and new host-parasite relationships have been reported, and this immense diversity in mammals raised questions, such as how this can influence the course of the infection in these animals and its transmissibility. Dogs demonstrated a high infection rate by T. cruzi as observed by positive serological results (92% in 2005 and 76% in 2007). The absence of positive parasitological tests confirmed their poor infectivity potential but their importance as sentinel hosts of T. cruzi transmission.


Assuntos
Doença de Chagas , Trypanosomatina , Animais , Brasil/epidemiologia , Cães , Ecossistema , Gambás , Filogenia , Ratos
3.
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
4.
Exp Cell Res ; 417(1): 113162, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35460679

RESUMO

The endoplasmic reticulum (ER) presents unique properties to establishing bacterium symbiosis in eukaryotic cells since it synthesizes and glycosylates essential molecules like proteins and lipids. Tunicamycin (TM) is an antibiotic that inhibits the first step in the N-linked glycosylation in eukaryotes and has been used as an ER stress inducer to activate the Unfolded Protein Response (UPR). Mutualistic symbiosis in trypanosomatids is characterized by structural adaptations and intense metabolic exchanges, thus we investigated the effects of TM in the association between Angomonas deanei and its symbiotic bacterium, through ultrastructural and proteomic approaches. Cells treated with the inhibitor showed a decrease in proliferation, enlargement of the ER and Golgi cisternae and an increased distance between the symbiont and the ER. TM proved to be an important tool to better understand ER stress in trypanosomatids, since changes in protein composition were observed in the host protozoan, especially the expression of the Hsp90 chaperone. Furthermore, data obtained indicates the importance of the ER for the adaptation and maintenance of symbiotic associations between prokaryotes and eukaryotes, considering that this organelle has recognized importance in the biogenesis and division of cell structures.


Assuntos
Proteínas de Choque Térmico , Trypanosomatina , Bactérias , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Proteínas de Choque Térmico/metabolismo , Proteômica , Trypanosomatina/metabolismo , Trypanosomatina/microbiologia , Tunicamicina/farmacologia
5.
Biochem Biophys Res Commun ; 604: 70-75, 2022 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-35299073

RESUMO

The patients with the most dreaded Leishmania donovani infections are now regularly been detected with co-infecting monoxenous trypanosomatid, Leptomonas seymouri, of which pathological consequence is obscure. Due to high degree of morphological similarity, its presence remains unmarked in the culture which leads to anomalous research outcomes. The available methods to detect Leptomonas in cultures are cumbersome and are not quantitative. We report here that MyosinXXI serves as a distinguishing biomarker that can be used to mark the presence of L. seymouri in Leishmania cultures. The method uses Leishmania MyosinXXI antibodies employed in immunofluorescence microscopy that shows a specialized localization pattern in Leishmania but not in Leptomonas (Patent application No. IN201711014439). This method is not only qualitative, but can also quantify the L. seymouri load in the cultured field isolates and serves as a remarkable tool to ascertain laboratory strains of Leishmania.


Assuntos
Leishmania donovani , Trypanosomatina , Humanos
6.
Parasitology ; 149(5): 654-666, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35115070

RESUMO

The vast majority of trypanosome species is vector-borne parasites, with some of them being medically and veterinary important (such as Trypanosoma cruzi and Trypanosoma brucei) and capable of causing serious illness in vertebrate hosts. The discovery of trypanosomes in bats emphasizes the importance of bats as an important reservoir. Interestingly, there is a hypothesis that bats are ancestral hosts of T. cruzi. Trypanosome diversity has never been investigated in bats in Thailand, despite being in a biodiversity hot spot. To gain a better understanding of the diversity and evolutionary relationship of trypanosomes, polymerase chain reaction-based surveys were carried out from 2018 to 2020 in 17 sites. A total of 576 bats were captured, representing 23 species. A total of 38 (6.6%) positive samples was detected in ten bat species. Trypanosoma dionisii and Trypanosoma noyesi were identified from Myotis siligorensis and Megaderma spasma, respectively. The remaining 18S rRNA sequences of trypanosomes were related to other trypanosomes previously reported elsewhere. The sequences in the current study showed nucleotide identity as low as 90.74% compared to those of trypanosomes in the GenBank database, indicating the possibility of new species. All bat trypanosomes identified in the current study fall within the T. cruzi clade. The current study adds to evidence linking T. noyesi to a bat trypanosome and further supports the bat host origin of the T. cruzi clade. To the best of authors' knowledge, this is the first study on bat trypanosomes in Thailand and their phylogenetic relationships with global isolates.


Assuntos
Quirópteros , Trypanosoma cruzi , Trypanosoma , Trypanosomatina , Animais , Quirópteros/parasitologia , DNA de Protozoário/genética , Filogenia , Tailândia/epidemiologia , Trypanosoma cruzi/genética , Trypanosomatina/genética
7.
PLoS Negl Trop Dis ; 16(1): e0010040, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35025891

RESUMO

The parasitic trypanosomatids cause lethal and debilitating diseases, the leishmaniases, Chagas disease, and the African trypanosomiases, with major impacts on human and animal health. Sustained research has borne fruit by assisting efforts to reduce the burden of disease and by improving our understanding of fundamental molecular and cell biology. But where has the research primarily been conducted, and which research areas have received the most attention? These questions are addressed below using publication and citation data from the past few decades.


Assuntos
Infecções por Euglenozoa/parasitologia , Pesquisa , Trypanosomatina , Animais , Infecções por Euglenozoa/epidemiologia , Saúde Global , Humanos
8.
Int J Parasitol ; 52(1): 65-75, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34416272

RESUMO

The remodelling of flagella into attachment structures is a common and important event in the trypanosomatid life cycle. Lotmaria passim and Crithidia mellificae can parasitize Apis mellifera, and as a result they might have a significant impact on honeybee health. However, there are details of their life cycle and the mechanisms underlying their pathogenicity in this host that remain unclear. Here we show that both L. passim promastigotes and C. mellificae choanomastigotes differentiate into haptomonad stages covering the ileum and rectum of honeybees. These haptomonad cells remain attached to the host surface via zonular hemidesmosome-like structures, as revealed by transmission electron microscopy. This work describes for the first known time the haptomonad morphotype of these species and their hemidesmosome-like attachments in A. mellifera, a key trait used by other trypanosomatid species to proliferate in the insect host hindgut.


Assuntos
Crithidia , Trypanosomatina , Animais , Abelhas
9.
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
10.
Proc Biol Sci ; 288(1964): 20211517, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34847766

RESUMO

Host temperature and gut chemistry can shape resistance to parasite infection. Heat and acidity can limit trypanosomatid infection in warm-blooded hosts and could shape infection resistance in insects as well. The colony-level endothermy and acidic guts of social bees provide unique opportunities to study how temperature and acidity shape insect-parasite associations. We compared temperature and pH tolerance between three trypanosomatid parasites from social bees and a related trypanosomatid from poikilothermic mosquitoes, which have alkaline guts. Relative to the mosquito parasites, all three bee parasites had higher heat tolerance that reflected body temperatures of hosts. Heat tolerance of the honeybee parasite Crithidia mellificae was exceptional for its genus, implicating honeybee endothermy as a plausible filter of parasite establishment. The lesser heat tolerance of the emerging Lotmaria passim suggests possible spillover from a less endothermic host. Whereas both honeybee parasites tolerated the acidic pH found in bee intestines, mosquito parasites tolerated the alkaline conditions found in mosquito midguts, suggesting that both gut pH and temperature could structure host-parasite specificity. Elucidating how host temperature and gut pH affect infection-and corresponding parasite adaptations to these factors-could help explain trypanosomatids' distribution among insects and invasion of mammals.


Assuntos
Parasitos , Trypanosomatina , Animais , Abelhas , Temperatura Corporal , Crithidia , Concentração de Íons de Hidrogênio , Mamíferos , Trypanosomatina/parasitologia
11.
Commun Biol ; 4(1): 953, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376792

RESUMO

Major Intrinsic Proteins (MIPs) are membrane channels that permeate water and other small solutes. Some trypanosomatid MIPs mediate the uptake of antiparasitic compounds, placing them as potential drug targets. However, a thorough study of the diversity of these channels is still missing. Here we place trypanosomatid channels in the sequence-function space of the large MIP superfamily through a sequence similarity network. This analysis exposes that trypanosomatid aquaporins integrate a distant cluster from the currently defined MIP families, here named aquaporin X (AQPX). Our phylogenetic analyses reveal that trypanosomatid MIPs distribute exclusively between aquaglyceroporin (GLP) and AQPX, being the AQPX family expanded in the Metakinetoplastina common ancestor before the origin of the parasitic order Trypanosomatida. Synteny analysis shows how African trypanosomes specifically lost AQPXs, whereas American trypanosomes specifically lost GLPs. AQPXs diverge from already described MIPs on crucial residues. Together, our results expose the diversity of trypanosomatid MIPs and will aid further functional, structural, and physiological research needed to face the potentiality of the AQPXs as gateways for trypanocidal drugs.


Assuntos
Aquagliceroporinas/genética , Aquaporinas/genética , Proteínas de Protozoários/genética , Trypanosomatina/genética , Sequência de Aminoácidos , Aquagliceroporinas/química , Aquaporinas/química , Proteínas de Protozoários/química , Alinhamento de Sequência , Trypanosomatina/química
12.
Folia Parasitol (Praha) ; 682021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34309583

RESUMO

Tsetse flies are well-known vectors of trypanosomes pathogenic for humans and livestock. For these strictly blood-feeding viviparous flies, the host blood should be the only source of nutrients and liquids, as well as any exogenous microorganisms colonising their intestine. Here we describe the unexpected finding of several monoxenous trypanosomatids in their gut. In a total of 564 individually examined Glossina (Austenia) tabaniformis (Westwood) (436 specimens) and Glossina (Nemorhina) fuscipes fuscipes (Newstead) (128 specimens) captured in the Dzanga-Sangha Protected Areas, Central African Republic, 24 (4.3%) individuals were infected with monoxenous trypanosomatids belonging to the genera Crithidia Léger, 1902; Kentomonas Votýpka, Yurchenko, Kostygov et Lukes, 2014; Novymonas Kostygov et Yurchenko, 2020; Obscuromonas Votýpka et Lukes, 2021; and Wallacemonas Kostygov et Yurchenko, 2014. Moreover, additional 20 (3.5%) inspected tsetse flies harboured free-living bodonids affiliated with the genera Dimastigella Sandon, 1928; Neobodo Vickerman, 2004; Parabodo Skuja, 1939; and Rhynchomonas Klebs, 1892. In the context of the recently described feeding behaviour of these dipterans, we propose that they become infected while taking sugar meals and water, providing indirect evidence that blood is not their only source of food and liquids.


Assuntos
Interações Hospedeiro-Parasita , Trypanosomatina/fisiologia , Moscas Tsé-Tsé , Animais , República Centro-Africana , Comportamento Alimentar , Moscas Tsé-Tsé/parasitologia , Moscas Tsé-Tsé/fisiologia
13.
An Acad Bras Cienc ; 93(2): e20190467, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133529

RESUMO

Rhinella major is one of the component species of the Rhinella granulosa group and is distributed in the neotropical region of the South American continent, being found in anthropized environments. The occurrence of trypanosomes in anurans involves a yet unknown diversity of species and hosts. In the present study, we aimed to describe the first record of Trypanosoma sp. at R. major as a new host. Of the species captured, four were positive for trypomastigote forms of Trypanosoma sp. The morphometry of the trypomastigote forms revealed parasitemia by only one morphotype. There is a need for reports and studies of parasite-host relationships in anurans and a lack of records regarding hemoparasite diversity linked to the Rhinella granulosa group.


Assuntos
Parasitos , Trypanosoma , Trypanosomatina , Animais , Anuros , Brasil , Filogenia
14.
J Invertebr Pathol ; 184: 107628, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34090931

RESUMO

Lotmaria passim is a trypanosomatid that infects honey bees. In this study, we established an axenic culture of L. passim from Italian isolates and then used its DNA as a control in subsequent analyses that investigated environmental DNA (eDNA) to detect this trypasonosomatid. The source of eDNA was honey, which has been already demonstrated to be useful to detect honey bee parasites. DNA from a total of 164 honey samples collected in the North of Italy was amplified with three L. passim specific PCR primers and 78% of the analysed samples gave positive results. These results indicated a high prevalence rate of this trypanosomatid in the North of Italy, where it might be considered another threat to honey bee health.


Assuntos
Abelhas/parasitologia , Mel/análise , Trypanosomatina/isolamento & purificação , Animais , Criação de Abelhas , Itália
15.
Sci Rep ; 11(1): 11233, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045562

RESUMO

Invasive species contribute to deteriorate the health of ecosystems due to their direct effects on native fauna and the local parasite-host dynamics. We studied the potential impact of the invasive hornet Vespa velutina on the European parasite-host system by comparing the patterns of diversity and abundance of pathogens (i.e. Microsporidia: Nosematidae; Euglenozoa: Trypanosomatidae and Apicomplexa: Lipotrophidae) in European V. velutina specimens with those in the native European hornet Vespa crabro, as well as other common Hymenoptera (genera Vespula, Polistes and Bombus). We show that (i) V. velutina harbours most common hymenopteran enteropathogens as well as several new parasitic taxa. (ii) Parasite diversity in V. velutina is most similar to that of V. crabro. (iii) No unambiguous evidence of pathogen release by V. velutina was detected. This evidence together with the extraordinary population densities that V. velutina reaches in Europe (around of 100,000 individuals per km2 per year), mean that this invasive species could severely alter the native pathogen-host dynamics either by actively contributing to the dispersal of the parasites and/or by directly interacting with them, which could have unexpected long-term harmful consequences on the native entomofauna.


Assuntos
Ecossistema , Himenópteros/parasitologia , Vespas/parasitologia , Animais , Apicomplexa , Euglenozoários , Europa (Continente) , Interações Hospedeiro-Parasita , Espécies Introduzidas , Microsporídios , Trypanosomatina
16.
Genes (Basel) ; 12(3)2021 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804709

RESUMO

While numerous genomes of Leishmania spp. have been sequenced and analyzed, an understanding of the evolutionary history of these organisms remains limited due to the unavailability of the sequence data for their closest known relatives, Endotrypanum and Porcisia spp., infecting sloths and porcupines. We have sequenced and analyzed genomes of three members of this clade in order to fill this gap. Their comparative analyses revealed only minute differences from Leishmaniamajor genome in terms of metabolic capacities. We also documented that the number of genes under positive selection on the Endotrypanum/Porcisia branch is rather small, with the flagellum-related group of genes being over-represented. Most significantly, the analysis of gene family evolution revealed a substantially reduced repertoire of surface proteins, such as amastins and biopterin transporters BT1 in the Endotrypanum/Porcisia species when compared to amastigote-dwelling Leishmania. This reduction was especially pronounced for δ-amastins, a subfamily of cell surface proteins crucial in the propagation of Leishmania amastigotes inside vertebrate macrophages and, apparently, dispensable for Endotrypanum/Porcisia, which do not infect such cells.


Assuntos
Proteínas de Membrana/genética , Trypanosomatina/classificação , Sequenciamento Completo do Genoma/métodos , Evolução Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Leishmania/classificação , Leishmania/genética , Leishmania major/classificação , Leishmania major/genética , Filogenia , Proteínas de Protozoários/genética , Trypanosomatina/genética , Virulência
17.
Molecules ; 26(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806654

RESUMO

Trypanosomatids are the causative agents of leishmaniasis and trypanosomiasis, which affect about 20 million people in the world's poorest countries, leading to 95,000 deaths per year. They are often associated with malnutrition, weak immune systems, low quality housing, and population migration. They are generally recognized as neglected tropical diseases. New drugs against these parasitic protozoa are urgently needed to counteract drug resistance, toxicity, and the high cost of commercially available drugs. Microbial bioprospecting for new molecules may play a crucial role in developing a new generation of antiparasitic drugs. This article reviews the current state of the available literature on chemically defined metabolites of microbial origin that have demonstrated antitrypanosomatid activity. In this review, bacterial and fungal metabolites are presented; they originate from a range of microorganisms, including cyanobacteria, heterotrophic bacteria, and filamentous fungi. We hope to provide a useful overview for future research to identify hits that may become the lead compounds needed to accelerate the discovery of new drugs against trypanosomatids.


Assuntos
Antiprotozoários/uso terapêutico , Bactérias/química , Fungos/química , Leishmaniose/tratamento farmacológico , Trypanosomatina/fisiologia , Tripanossomíase/tratamento farmacológico , Animais , Humanos , Leishmaniose/metabolismo , Tripanossomíase/metabolismo
18.
Sci Rep ; 11(1): 9210, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33911164

RESUMO

Angomonas deanei coevolves in a mutualistic relationship with a symbiotic bacterium that divides in synchronicity with other host cell structures. Trypanosomatid mitochondrial DNA is contained in the kinetoplast and is composed of thousands of interlocked DNA circles (kDNA). The arrangement of kDNA is related to the presence of histone-like proteins, known as KAPs (kinetoplast-associated proteins), that neutralize the negatively charged kDNA, thereby affecting the activity of mitochondrial enzymes involved in replication, transcription and repair. In this study, CRISPR-Cas9 was used to delete both alleles of the A. deanei KAP4 gene. Gene-deficient mutants exhibited high compaction of the kDNA network and displayed atypical phenotypes, such as the appearance of a filamentous symbionts, cells containing two nuclei and one kinetoplast, and division blocks. Treatment with cisplatin and UV showed that Δkap4 null mutants were not more sensitive to DNA damage and repair than wild-type cells. Notably, lesions caused by these genotoxic agents in the mitochondrial DNA could be repaired, suggesting that the kDNA in the kinetoplast of trypanosomatids has unique repair mechanisms. Taken together, our data indicate that although KAP4 is not an essential protein, it plays important roles in kDNA arrangement and replication, as well as in the maintenance of symbiosis.


Assuntos
Bactérias/metabolismo , Replicação do DNA , DNA de Cinetoplasto/genética , DNA de Protozoário/genética , Mitocôndrias/genética , Proteínas de Protozoários/genética , Trypanosomatina/genética , Divisão Celular , Núcleo Celular , DNA de Cinetoplasto/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , DNA de Protozoário/metabolismo , Mitocôndrias/metabolismo , Proteínas de Protozoários/metabolismo , Simbiose , Trypanosomatina/metabolismo , Trypanosomatina/microbiologia
19.
Zootaxa ; 4958(1): zootaxa.4958.1.36, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33903483

RESUMO

The Ochlerini (Discocephalinae) are endemic in the Neotropical region, and the tribe currently contains 38 genera and 149 species. The monotypic Macropygium Spinola, 1837 is the most widespread ochlerine genus in the Americas, ranging from Mexico to Argentina. Macropygium reticulare (Fabricius, 1803) is one of the few Ochlerini of phytosanitary importance, transmitting Phytomonas spp. in palm crops in South America. Nonetheless its wide distribution, and phytosanitary importance, the taxonomy of Macropygium has been neglected. Here we present a revision of Macropygium, revalidate three species, Macropygium spinolae Stål, 1860, REVISED STATUS (removed from the synonymy with M. reticulare), Macropygium bifidum (Westwood, 1837), NEW COMBINATION (removed from the synonymy with M. reticulare), and Macropygium subsulcatum (Amyot Serville, 1843), REVISED STATUS (removed from the synonymy with M. reticulare). We remove Ochlerus guttipes Walker, 1867 from the synonymy with M. reticulare, and propose O. guttipes a new junior synonym of M. spinolae. Finally, we describe one new species, Macropygium graziae Silva Campos, Sp. Nov.. A key for the species of Macropygium is provided.


Assuntos
Heterópteros , Animais , Hemípteros , Heterópteros/classificação , Trypanosomatina
20.
Exp Parasitol ; 224: 108102, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33775649

RESUMO

The human pathogenic trypanosomatid species collectively called the "TriTryp parasites" - Trypanosoma brucei, Trypanosoma cruzi and Leishmania spp. - have complex life cycles, with each of these parasitic protists residing in a different niche during their successive developmental stages where they encounter diverse nutrients. Consequently, they adapt their metabolic network accordingly. Yet, throughout the life cycles, carbohydrate metabolism - involving the glycolytic, gluconeogenic and pentose-phosphate pathways - always plays a central role in the biology of these parasites, whether the available carbon and free energy sources are saccharides, amino acids or lipids. In this paper, we provide an updated review of the carbohydrate metabolism of the TriTryps, highlighting new data about this metabolic network, the interconnection of its pathways and the compartmentalisation of its enzymes within glycosomes, cytosol and mitochondrion. Differences in the expression of the branches of the metabolic network between the successive life-cycle stages of each of these parasitic trypanosomatids are discussed, as well as differences between them. Recent structural and kinetic studies have revealed unique regulatory mechanisms for some of the network's key enzymes with important species-specific variations. Furthermore, reports of multiple post-translational modifications of trypanosomal glycolytic enzymes suggest that additional mechanisms for stage- and/or environmental cues that regulate activity are operational in the parasites. The detailed comparison of the carbohydrate metabolism of the TriTryps has thus revealed multiple differences and a greater complexity, including for the reduced metabolic network in bloodstream-form T. brucei, than previously appreciated. Although these parasites are related, share many cytological and metabolic features and are grouped within a single taxonomic family, the differences highlighted in this review reflect their separate evolutionary tracks from a common ancestor to the extant organisms. These differences are indicative of their adaptation to the different insect vectors and niches occupied in their mammalian hosts.


Assuntos
Metabolismo dos Carboidratos/fisiologia , Trypanosomatina/metabolismo , Metabolismo Energético , Galactose/metabolismo , Gluconeogênese/fisiologia , Glicólise/fisiologia , Trypanosomatina/enzimologia
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