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1.
Curr Biol ; 34(8): 1810-1816.e4, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38608678

RESUMO

Coral reefs are a biodiversity hotspot,1,2 and the association between coral and intracellular dinoflagellates is a model for endosymbiosis.3,4 Recently, corals and related anthozoans have also been found to harbor another kind of endosymbiont, apicomplexans called corallicolids.5 Apicomplexans are a diverse lineage of obligate intracellular parasites6 that include human pathogens such as the malaria parasite, Plasmodium.7 Global environmental sequencing shows corallicolids are tightly associated with tropical and subtropical reef environments,5,8,9 where they infect diverse corals across a range of depths in many reef systems, and correlate with host mortality during bleaching events.10 All of this points to corallicolids being ecologically significant to coral reefs, but it is also possible they are even more widely distributed because most environmental sampling is biased against parasites that maintain a tight association with their hosts throughout their life cycle. We tested the global distribution of corallicolids using a more direct approach, by specifically targeting potential anthozoan host animals from cold/temperate marine waters outside the coral reef context. We found that corallicolids are in fact common in such hosts, in some cases at high frequency, and that they infect the same tissue as parasites from topical coral reefs. Parasite phylogeny suggests corallicolids move between hosts and habitats relatively frequently, but that biogeography is more conserved. Overall, these results greatly expand the range of corallicolids beyond coral reefs, suggesting they are globally distributed parasites of marine anthozoans, which also illustrates significant blind spots that result from strategies commonly used to sample microbial biodiversity.


Assuntos
Antozoários , Recifes de Corais , Antozoários/parasitologia , Animais , Apicomplexa/fisiologia , Apicomplexa/genética , Apicomplexa/classificação , Simbiose , Temperatura Baixa , Dinoflagelados/fisiologia , Dinoflagelados/genética , Interações Hospedeiro-Parasita
2.
Parasitology ; 151(4): 400-411, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38465385

RESUMO

Individual organisms can host multiple species of parasites (or symbionts), and one species of parasite can infect different host species, creating complex interactions among multiple hosts and parasites. When multiple parasite species coexist in a host, they may compete or use strategies, such as spatial niche partitioning, to reduce competition. Here, we present a host­symbiont system with two species of Selenidium (Apicomplexa, Gregarinida) and one species of astome ciliate co-infecting two different species of slime feather duster worms (Annelida, Sabellidae, Myxicola) living in neighbouring habitats. We examined the morphology of the endosymbionts with light and scanning electron microscopy (SEM) and inferred their phylogenetic interrelationships using small subunit (SSU) rDNA sequences. In the host 'Myxicola sp. Quadra', we found two distinct species of Selenidium; S. cf. mesnili exclusively inhabited the foregut, and S. elongatum n. sp. inhabited the mid to hindgut, reflecting spatial niche partitioning. Selenidium elongatum n. sp. was also present in the host M. aesthetica, which harboured the astome ciliate Pennarella elegantia n. gen. et sp. Selenidium cf. mesnili and P. elegantia n. gen. et sp. were absent in the other host species, indicating host specificity. This system offers an intriguing opportunity to explore diverse aspects of host­endosymbiont interactions and competition among endosymbionts.


Assuntos
Apicomplexa , Especificidade de Hospedeiro , Filogenia , Simbiose , Animais , Apicomplexa/fisiologia , Apicomplexa/genética , Apicomplexa/classificação , Apicomplexa/ultraestrutura , Coinfecção/parasitologia , Coinfecção/veterinária , Cilióforos/fisiologia , Cilióforos/classificação , Cilióforos/genética , Anelídeos , Interações Hospedeiro-Parasita , Microscopia Eletrônica de Varredura , Doenças das Aves/parasitologia
3.
Nucleic Acids Res ; 50(D1): D898-D911, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34718728

RESUMO

The Eukaryotic Pathogen, Vector and Host Informatics Resource (VEuPathDB, https://veupathdb.org) represents the 2019 merger of VectorBase with the EuPathDB projects. As a Bioinformatics Resource Center funded by the National Institutes of Health, with additional support from the Welllcome Trust, VEuPathDB supports >500 organisms comprising invertebrate vectors, eukaryotic pathogens (protists and fungi) and relevant free-living or non-pathogenic species or hosts. Designed to empower researchers with access to Omics data and bioinformatic analyses, VEuPathDB projects integrate >1700 pre-analysed datasets (and associated metadata) with advanced search capabilities, visualizations, and analysis tools in a graphic interface. Diverse data types are analysed with standardized workflows including an in-house OrthoMCL algorithm for predicting orthology. Comparisons are easily made across datasets, data types and organisms in this unique data mining platform. A new site-wide search facilitates access for both experienced and novice users. Upgraded infrastructure and workflows support numerous updates to the web interface, tools, searches and strategies, and Galaxy workspace where users can privately analyse their own data. Forthcoming upgrades include cloud-ready application architecture, expanded support for the Galaxy workspace, tools for interrogating host-pathogen interactions, and improved interactions with affiliated databases (ClinEpiDB, MicrobiomeDB) and other scientific resources, and increased interoperability with the Bacterial & Viral BRC.


Assuntos
Bases de Dados Factuais , Vetores de Doenças/classificação , Interações Hospedeiro-Patógeno/genética , Fenótipo , Interface Usuário-Computador , Animais , Apicomplexa/classificação , Apicomplexa/genética , Apicomplexa/patogenicidade , Bactérias/classificação , Bactérias/genética , Bactérias/patogenicidade , Doenças Transmissíveis/microbiologia , Doenças Transmissíveis/parasitologia , Doenças Transmissíveis/patologia , Doenças Transmissíveis/transmissão , Biologia Computacional/métodos , Mineração de Dados/métodos , Diplomonadida/classificação , Diplomonadida/genética , Diplomonadida/patogenicidade , Fungos/classificação , Fungos/genética , Fungos/patogenicidade , Humanos , Insetos/classificação , Insetos/genética , Insetos/patogenicidade , Internet , Nematoides/classificação , Nematoides/genética , Nematoides/patogenicidade , Filogenia , Virulência , Fluxo de Trabalho
4.
Nucleic Acids Res ; 50(D1): D962-D969, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34718745

RESUMO

Sequence compositions of nucleic acids and proteins have significant impact on gene expression, RNA stability, translation efficiency, RNA/protein structure and molecular function, and are associated with genome evolution and adaptation across all kingdoms of life. Therefore, a devoted resource of sequence compositions and associated features is fundamentally crucial for a wide range of biological research. Here, we present CompoDynamics (https://ngdc.cncb.ac.cn/compodynamics/), a comprehensive database of sequence compositions of coding sequences (CDSs) and genomes for all kinds of species. Taking advantage of the exponential growth of RefSeq data, CompoDynamics presents a wealth of sequence compositions (nucleotide content, codon usage, amino acid usage) and derived features (coding potential, physicochemical property and phase separation) for 118 689 747 high-quality CDSs and 34 562 genomes across 24 995 species. Additionally, interactive analytical tools are provided to enable comparative analyses of sequence compositions and molecular features across different species and gene groups. Collectively, CompoDynamics bears the great potential to better understand the underlying roles of sequence composition dynamics across genes and genomes, providing a fundamental resource in support of a broad spectrum of biological studies.


Assuntos
Uso do Códon , Bases de Dados Genéticas , Genoma , Fases de Leitura Aberta , Software , Sequência de Aminoácidos , Animais , Apicomplexa/classificação , Apicomplexa/genética , Archaea/classificação , Archaea/genética , Bactérias/classificação , Bactérias/genética , Composição de Bases , Sequência de Bases , Fungos/classificação , Fungos/genética , Código Genético , Internet , Invertebrados/classificação , Invertebrados/genética , Filogenia , Plantas/classificação , Plantas/genética , Vertebrados/classificação , Vertebrados/genética , Vírus/classificação , Vírus/genética
5.
Nucleic Acids Res ; 50(D1): D837-D847, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34788826

RESUMO

Since 2005, the Pathogen-Host Interactions Database (PHI-base) has manually curated experimentally verified pathogenicity, virulence and effector genes from fungal, bacterial and protist pathogens, which infect animal, plant, fish, insect and/or fungal hosts. PHI-base (www.phi-base.org) is devoted to the identification and presentation of phenotype information on pathogenicity and effector genes and their host interactions. Specific gene alterations that did not alter the in host interaction phenotype are also presented. PHI-base is invaluable for comparative analyses and for the discovery of candidate targets in medically and agronomically important species for intervention. Version 4.12 (September 2021) contains 4387 references, and provides information on 8411 genes from 279 pathogens, tested on 228 hosts in 18, 190 interactions. This provides a 24% increase in gene content since Version 4.8 (September 2019). Bacterial and fungal pathogens represent the majority of the interaction data, with a 54:46 split of entries, whilst protists, protozoa, nematodes and insects represent 3.6% of entries. Host species consist of approximately 54% plants and 46% others of medical, veterinary and/or environmental importance. PHI-base data is disseminated to UniProtKB, FungiDB and Ensembl Genomes. PHI-base will migrate to a new gene-centric version (version 5.0) in early 2022. This major development is briefly described.


Assuntos
Bases de Dados Factuais , Interações Hospedeiro-Patógeno/genética , Fenótipo , Interface Usuário-Computador , Animais , Apicomplexa/classificação , Apicomplexa/genética , Apicomplexa/patogenicidade , Bactérias/classificação , Bactérias/genética , Bactérias/patogenicidade , Diplomonadida/classificação , Diplomonadida/genética , Diplomonadida/patogenicidade , Fungos/classificação , Fungos/genética , Fungos/patogenicidade , Insetos/classificação , Insetos/genética , Insetos/patogenicidade , Internet , Nematoides/classificação , Nematoides/genética , Nematoides/patogenicidade , Filogenia , Plantas/microbiologia , Plantas/parasitologia , Virulência
6.
Folia Parasitol (Praha) ; 682021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34642289

RESUMO

Stomatocystis goerresi sp. n., a gregarine (phylum Apicomplexa, Monocystidae) parasite of an important invasive earthworm in North America, Amynthas tokioensis (Beddard), is described. This is the second species placed into the genus, and details of its morphology and life cycle support Stomatocystis Bandyopadhyay, Mitra et Göçmen, 2006 as a valid taxon. The new species is described using standard nomenclature, measurements, shape descriptors, and photographs of living cells. The parasite was found only in A. tokioensis, and absent in sympatric earthworm species, suggesting it arrived when the earthworms were introduced from their origin from Japan. The species is distinctive from the type species in the genus, S. indica Bandyopadhyay, Mitra et Göçmen, 2006, in being substantially larger in all stages, found in only the host's seminal vesicles, and found in a different host species from East Asia. The distinctive trophozoites/gamonts develop a large funnel structure ringed with a collar of pronounced ridges, and the funnel appears even in the smallest cells. This funnel varies greatly in relative size (to the cell body) and shape, sometimes forming a large fan. The life cycle of S. goerresi is described including distinctive syzygy in which the funnels fuse and then produce a large cell with local centres of isogamete production (thus sex without gender). Gametes are large ( ~5 µm) spheres with complex tips. Oocyst production is large, > 1,000 per mature gametocyst. The genus Stomatocystis is placed into the Monocystidae, but the life cycle of the new species differs from those of other monocystid taxa, which may mean the Monocystidae are not monophyletic or life cycles are variable within the family. Prevalence of S. goerresi at the type locality was high (~ 90%). The parasites destroy the earthworm's organ of sperm self-storage thus eliminating the male function in the hermaphroditic host which may influence the ability of the earthworm to invade and be successful at new sites.


Assuntos
Apicomplexa/crescimento & desenvolvimento , Apicomplexa/isolamento & purificação , Animais , Apicomplexa/classificação , Apicomplexa/genética , Espécies Introduzidas , Japão , Estágios do Ciclo de Vida , Masculino , Oligoquetos/parasitologia
7.
J Invertebr Pathol ; 183: 107622, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34043973

RESUMO

Apicomplexa (sensu stricto) are a diverse group of obligate parasites to a variety of animal species. Gregarines have been the subject of particular interest due to their diversity, phylogenetically basal position, and more recently, their symbiotic relationships with their hosts. In the present study, four new species of marine eugregarines infecting ascidian hosts (Lankesteria kaiteriteriensis sp. nov., L. dolabra sp. nov., L. savignyii sp. nov., and L. pollywoga sp. nov.) were described using a combination of morphological and molecular data. Phylogenetic analysis using small subunit rDNA sequences suggested that gregarines that parasitize ascidians and polychaetes share a common origin as traditionally hypothesized by predecessors in the discipline. However, Lankesteria and Lecudina species did not form clades as expected, but were instead intermixed amongst each other and their respective type species in the phylogeny. These two major genera are therefore taxonomically problematic. We hypothesize that the continued addition of new species from polychaete and tunicate hosts as well as the construction of multigene phylogenies that include type-material will further dissolve the currently accepted distinction between Lankesteria and Lecudina. The species discovered and described in the current study add new phylogenetic and taxonomic data to the knowledge of marine gregarine parasitism in ascidian hosts.


Assuntos
Apicomplexa/classificação , Interações Hospedeiro-Parasita , Urocordados/parasitologia , Animais , Apicomplexa/fisiologia , Evolução Biológica
8.
Microb Genom ; 7(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33656416

RESUMO

The RNA binding domain abundant in apicomplexans (RAP) is a protein domain identified in a diverse group of proteins, called RAP proteins, many of which have been shown to be involved in RNA binding. To understand the expansion and potential function of the RAP proteins, we conducted a hidden Markov model based screen among the proteomes of 54 eukaryotes, 17 bacteria and 12 archaea. We demonstrated that the domain is present in closely and distantly related organisms with particular expansions in Alveolata and Chlorophyta, and are not unique to Apicomplexa as previously believed. All RAP proteins identified can be decomposed into two parts. In the N-terminal region, the presence of variable helical repeats seems to participate in the specific targeting of diverse RNAs, while the RAP domain is mostly identified in the C-terminal region and is highly conserved across the different phylogenetic groups studied. Several conserved residues defining the signature motif could be crucial to ensure the function(s) of the RAP proteins. Modelling of RAP domains in apicomplexan parasites confirmed an ⍺/ß structure of a restriction endonuclease-like fold. The phylogenetic trees generated from multiple alignment of RAP domains and full-length proteins from various distantly related eukaryotes indicated a complex evolutionary history of this family. We further discuss these results to assess the potential function of this protein family in apicomplexan parasites.


Assuntos
Apicomplexa/classificação , Apicomplexa/genética , Proteínas de Protozoários/genética , Proteínas de Ligação a RNA/genética , Sequência de Aminoácidos , Apicomplexa/química , Apicomplexa/metabolismo , Filogenia , Conformação Proteica em alfa-Hélice , Domínios Proteicos , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Alinhamento de Sequência
9.
Parasite ; 28: 12, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33620310

RESUMO

Orthoptera are infected by about 60 species of gregarines assigned to the genus Gregarina Dufour, 1828. Among these species, Gregarina garnhami Canning, 1956 from Schistocerca gregaria (Forsskål, 1775) was considered by Lipa et al. in 1996 to be synonymous with Gregarina acridiorum (Léger 1893), a parasite of several orthopteran species including Locusta migratoria (Linné, 1758). Here, a morphological study and molecular analyses of the SSU rDNA marker demonstrate that specimens of S. gregaria and specimens of L. migratoria are infected by two distinct Gregarina species, G. garnhami and G. acridiorum, respectively. Validation of the species confirms that molecular analyses provide useful taxonomical information. Phenotypic plasticity was clearly observed in the case of G. garnhami: the morphology of its trophozoites, gamonts and syzygies varied according to the geographical location of S. gregaria and the subspecies infected.


TITLE: La taxonomie intégrative confirme que Gregarina garnhami et G. acridiorum (Apicomplexa, Gregarinidae), parasites de Schistocerca gregaria et Locusta migratoria (Insecta, Orthoptera), sont des espèces distinctes. ABSTRACT: Les orthoptères sont parasités par environ soixante espèces de grégarines affiliées au genre Gregarina Dufour, 1828. Parmi ces espèces Gregarina garnhami Canning, 1956 décrite chez Schistocerca gregaria (Forskål, 1775), a été mise en synonymie par Lipa et al. en 1996 avec Gregarina acridiorum (Léger 1893), parasite de plusieurs espèces d'orthoptères dont Locusta migratoria (Linné, 1758). Ici, une étude morphologique et des analyses moléculaires du marqueur SSU rDNA démontrent que les spécimens de S. gregaria et ceux de L. migratoria sont infectés par 2 espèces distinctes de grégarines, Gregarina garnhami et Gregarina acridiorum, respectivement. La validation de ces espèces confirme l'importance des informations fournies par les analyses moléculaires dans les études taxonomiques. Une plasticité phénotypique a été clairement observée dans le cas de G. garnhami : la morphologie de ses trophozoïtes, gamontes et syzygies varie selon la localisation géographique et la sous-espèce de S. gregaria infectée.


Assuntos
Apicomplexa/classificação , Especiação Genética , Locusta migratoria/parasitologia , Animais , DNA Ribossômico/genética
10.
Genome Biol Evol ; 13(2)2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33566096

RESUMO

The phylum Apicomplexa consists largely of obligate animal parasites that include the causative agents of human diseases such as malaria. Apicomplexans have also emerged as models to study the evolution of nonphotosynthetic plastids, as they contain a relict chloroplast known as the apicoplast. The apicoplast offers important clues into how apicomplexan parasites evolved from free-living ancestors and can provide insights into reductive organelle evolution. Here, we sequenced the transcriptomes and apicoplast genomes of three deep-branching apicomplexans, Margolisiella islandica, Aggregata octopiana, and Merocystis kathae. Phylogenomic analyses show that these taxa, together with Rhytidocystis, form a new lineage of apicomplexans that is sister to the Coccidia and Hematozoa (the lineages including most medically significant taxa). Members of this clade retain plastid genomes and the canonical apicomplexan plastid metabolism. However, the apicoplast genomes of Margolisiella and Rhytidocystis are the most reduced of any apicoplast, are extremely GC-poor, and have even lost genes for the canonical plastidial RNA polymerase. This new lineage of apicomplexans, for which we propose the class Marosporida class nov., occupies a key intermediate position in the apicomplexan phylogeny, and adds a new complexity to the models of stepwise reductive evolution of genome structure and organelle function in these parasites.


Assuntos
Apicomplexa/classificação , Apicomplexa/genética , Apicoplastos/genética , Tamanho do Genoma , Animais , Vias Biossintéticas/genética , Coccídios/genética , RNA Polimerases Dirigidas por DNA/genética , Eimeriidae/genética , Evolução Molecular , Invertebrados/parasitologia , Filogenia , Proteínas de Protozoários/classificação , Transcrição Gênica
11.
Parasitology ; 148(6): 747-759, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33536100

RESUMO

Haemogregarines (Adeleorina) have a high prevalence in turtles. Nevertheless, there is only one Hepatozoon species described that infects Testudines so far; it is Hepatozoon fitzsimonsi which infects the African tortoise Kinixys belliana. Colombia harbours a great diversity of chelonians; however, most of them are threatened. It is important to identify and characterize chelonian haemoparasite infections to improve the clinical assessments, treatments and the conservation and reintroduction programs of these animals. To evaluate such infections for the Colombian wood turtle Rhinoclemmys melanosterna, we analysed blood from 70 individuals. By using the morphological characteristics of blood stages as well as molecular information (18S rRNA sequences), here we report a new Hepatozoon species that represents the first report of a hepatozoid species infecting a semi-aquatic continental turtle in the world. Although the isolated lineage clusters within the phylogenetic clades that have morphological species of parasites already determined, their low nodal support makes their position within each group inconclusive. It is important to identify new molecular markers to improve parasite species identification. In-depth research on blood parasites infecting turtles is essential for increasing knowledge that could assess this potential unknown threat, to inform the conservation of turtles and for increasing the state of knowledge on parasites.


Assuntos
Apicomplexa/classificação , Apicomplexa/genética , Filogenia , Infecções Protozoárias em Animais/parasitologia , Tartarugas/parasitologia , Animais , Apicomplexa/ultraestrutura , Teorema de Bayes , DNA de Protozoário/sangue , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Marcadores Genéticos , Funções Verossimilhança , RNA Ribossômico 18S/genética , Alinhamento de Sequência/veterinária
12.
Nucleic Acids Res ; 49(D1): D212-D220, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33106848

RESUMO

RNAcentral is a comprehensive database of non-coding RNA (ncRNA) sequences that provides a single access point to 44 RNA resources and >18 million ncRNA sequences from a wide range of organisms and RNA types. RNAcentral now also includes secondary (2D) structure information for >13 million sequences, making RNAcentral the world's largest RNA 2D structure database. The 2D diagrams are displayed using R2DT, a new 2D structure visualization method that uses consistent, reproducible and recognizable layouts for related RNAs. The sequence similarity search has been updated with a faster interface featuring facets for filtering search results by RNA type, organism, source database or any keyword. This sequence search tool is available as a reusable web component, and has been integrated into several RNAcentral member databases, including Rfam, miRBase and snoDB. To allow for a more fine-grained assignment of RNA types and subtypes, all RNAcentral sequences have been annotated with Sequence Ontology terms. The RNAcentral database continues to grow and provide a central data resource for the RNA community. RNAcentral is freely available at https://rnacentral.org.


Assuntos
Bases de Dados de Ácidos Nucleicos/organização & administração , Anotação de Sequência Molecular , RNA não Traduzido/genética , Software , Animais , Apicomplexa/classificação , Apicomplexa/genética , Sequência de Bases , Betacoronavirus/classificação , Betacoronavirus/genética , Bases de Dados de Ácidos Nucleicos/provisão & distribuição , Fungos/classificação , Fungos/genética , Ontologia Genética , Humanos , Internet , Conformação de Ácido Nucleico , RNA não Traduzido/classificação , RNA não Traduzido/metabolismo , Análise de Sequência de RNA
13.
Environ Microbiol ; 23(1): 478-483, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33225560

RESUMO

Assessing the extent of parasite diversity requires the application of appropriate molecular tools, especially given the growing evidence of multiple parasite co-occurrence. Here, we compared the performance of a next-generation sequencing technology (Ion PGM ™ System) in 12 Bombus terrestris specimens that were PCR-identified as positive for trypanosomatids (Leishmaniinae) in a previous study. These bumblebees were also screened for the occurrence of Nosematidae and Neogregarinorida parasites using both classical protocols (either specific PCR amplification or amplification with broad-range primers plus Sanger sequencing) and Ion PGM sequencing. The latter revealed higher parasite diversity within individuals, especially among Leishmaniinae (which were present as a combination of Lotmaria passim, Crithidia mellificae and Crithidia bombi), and the occurrence of taxa never reported in these hosts: Crithidia acanthocephali and a novel neogregarinorida species. Furthermore, the complementary results produced by the different sets of primers highlighted the convenience of using multiple markers to minimize the chance of some target organisms going unnoticed. Altogether, the deep sequencing methodology offered a more comprehensive way to investigate parasite diversity than the usual identification methods and provided new insights whose importance for bumblebee health should be further analysed.


Assuntos
Abelhas/parasitologia , Biodiversidade , Parasitos/isolamento & purificação , Animais , Apicomplexa/classificação , Apicomplexa/genética , Apicomplexa/isolamento & purificação , Crithidia/genética , Crithidia/isolamento & purificação , Primers do DNA/genética , Sequenciamento de Nucleotídeos em Larga Escala , Parasitos/classificação , Parasitos/genética , Reação em Cadeia da Polimerase , Trypanosomatina/classificação , Trypanosomatina/genética , Trypanosomatina/isolamento & purificação
14.
J Parasitol ; 106(6): 735-741, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33260209

RESUMO

Monocystis perplexa n. sp., a parasite of an important invasive Japanese earthworm in North America, Amynthas agrestis, is described from a site in Vermont. An improved standard for Monocystis species descriptions is proposed including a standard nomenclature to reduce synonymies, a standard set of biometrics and shape descriptions for living cells, and a DNA genomic sequence for the 18S rRNA (∼1,700 base pairs). Comparing morphologies of Monocystis parasites in sympatric earthworm species indicates that M. perplexa is specific to A. agrestis in the study region. Also, polymerase chain reaction primers specific to M. perplexa amplified samples of A. agrestis earthworms taken from several sites in Japan. This suggests the parasite entered North America from Japan, the origin of the invasive Amynthas earthworm, and thus M. perplexa would be the first Monocystis described from the diverse Japanese Amynthas earthworms and the first from East Asia. Monocystis perplexa was found in every population of A. agrestis surveyed in Vermont, always reaching 100% prevalence by late summer (the host has an annual life cycle in Vermont). The 18S gene sequence differed from that of Monocystis agilis from the sympatric earthworm Lumbricus terrestris (the only other sequence available for Monocystis), and a genetic similarity tree places them closest among other gregarines. Many of the 95 described species of Monocystis are very similar in morphology (based on species descriptions), so the 18S gene can act as a barcode for Monocystis species and thus will help to eliminate both synonymies and reveal cryptic species.


Assuntos
Apicomplexa/classificação , Oligoquetos/parasitologia , Animais , Apicomplexa/genética , Apicomplexa/crescimento & desenvolvimento , Apicomplexa/isolamento & purificação , DNA de Protozoário/isolamento & purificação , Especificidade de Hospedeiro , Espécies Introduzidas , Japão , Oligoquetos/classificação , Reação em Cadeia da Polimerase , RNA Ribossômico 18S/genética , Estações do Ano , Alinhamento de Sequência , Solo , Vermont
15.
Parasit Vectors ; 13(1): 575, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33176856

RESUMO

Recently Greay et al. (Parasit Vectors 11:197, 2018) described several new Apicomplexa parasites from domestic companion animals in Australia. Harris (Parasit Vectors 12;172, 2019) highlighted that these descriptions did not conform to the International Code of Zoological Nomenclature (ICZN) rules. Despite Harris (2019) clearly noting "molecular characters can be used to satisfy article 13.1.1 of the code", in a reply Greay et al. (Parasit Vectors 12:178, 2019) incorrectly state "Harris considers the eight new species…invalid on the basis that only molecular characters were provided". This was not the case. The ICZN has strict rules regarding species descriptions for good reasons. Here I reiterate why the forms described by Greay et al. (2018) are not valid.


Assuntos
Apicomplexa/classificação , Animais de Estimação/parasitologia , Filogenia , Animais , Austrália , Ixodidae/parasitologia , RNA Ribossômico 18S/genética , Terminologia como Assunto
16.
Parasitol Res ; 119(11): 3739-3753, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33000433

RESUMO

Many tick-borne pathogens (TBPs) are present in wildlife. The objective of this study is to reveal the role of wild bears in maintaining TBPs. A total of 49 brown bears (Ursus arctos yesoensis) from Hokkaido, and 18 Japanese black bears (Ursus thibetanus japonicus) from Tochigi, and 66 Japanese black bears from Nagano were examined by two molecular methods, reverse line blot (RLB) hybridization, and nested PCR. A total of 5 TBPs (Hepatozoon ursi, Babesia sp. UR2-like group, Cytauxzoon sp. UR1, Babesia sp. UR1, and Babesia microti) were detected from bear blood DNA samples. B. microti was detected from blood DNA samples of Japanese black bear for the first time, with the prevalence of 6.0% (5/84). Out of detected pathogens, H. ursi, Babesia sp. UR2-like pathogens, and Cytauxzoon sp. UR1 were considered as three of the most prevalent TBPs in bears. The prevalence of H. ursi were significantly higher in Japanese black bear (0% vs 96.4%) while that of Babesia sp. UR2-like group was higher in Hokkaido brown bears (89.8% vs 40.5%). The prevalence of Babesia sp. UR1 were significantly higher in Japanese black bears from Tochigi (44.4%), comparing with those from Nagano (18.2%). The prevalence of the detected TBPs were significantly higher in adult bears, comparing with those in younger bears. The present study suggests that Japanese bear species contribute in the transmission of several TBPs in Japan. The expanding distribution of bears might cause the accidental transmission of TBPs to humans and domestic animals.


Assuntos
Apicomplexa/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Ursidae/parasitologia , Animais , Animais Selvagens/parasitologia , Apicomplexa/classificação , Apicomplexa/genética , DNA de Protozoário/genética , Japão/epidemiologia , Prevalência , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/transmissão , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/parasitologia , Doenças Transmitidas por Carrapatos/transmissão , Carrapatos/parasitologia
17.
Parasitol Res ; 119(10): 3469-3479, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32827104

RESUMO

Amphibians are among the most threatened vertebrate groups in the world, and the main causes include climate change, habitat destruction, and emerging diseases. Herein, we investigated the occurrence and characterized molecularly Apicomplexa in anurans from southeastern Brazil. Forty individuals from seven anuran species were sampled in São Paulo state. In the molecular analyses, one Leptodactylus latrans and one Rhinella diptycha were positive in PCR assays for species of Hepatozoon. Two L. latrans were also positive for coccidian infections (Lankesterella sp. and an unidentified coccidian species). Phylogenetic analysis based on 18S rDNA clustered the sequences detected in anurans from the present study with Hepatozoon spp. detected in reptiles and other anurans from Brazil, albeit they were separate from Hepatozoon haplotypes detected in frogs from Africa and North America. Our study showed, for the first time, the molecular detection of Lankesterella sp. and another coccidian in L. latrans. Additionally, co-infection by different species of Hepatozoon haplotypes and an unidentified coccidian in anurans from Brazil was documented.


Assuntos
Anuros/parasitologia , Apicomplexa/genética , Apicomplexa/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Animais , Anuros/classificação , Apicomplexa/classificação , Brasil/epidemiologia , Coccídios/classificação , Coccídios/genética , Coccídios/isolamento & purificação , Coccidiose/epidemiologia , Coccidiose/parasitologia , Coccidiose/veterinária , DNA de Protozoário/genética , DNA Ribossômico/genética , Filogenia , Infecções Protozoárias em Animais/epidemiologia
18.
PLoS Pathog ; 16(8): e1008717, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32745123

RESUMO

Hepatocystis is a genus of single-celled parasites infecting, amongst other hosts, monkeys, bats and squirrels. Although thought to have descended from malaria parasites (Plasmodium spp.), Hepatocystis spp. are thought not to undergo replication in the blood-the part of the Plasmodium life cycle which causes the symptoms of malaria. Furthermore, Hepatocystis is transmitted by biting midges, not mosquitoes. Comparative genomics of Hepatocystis and Plasmodium species therefore presents an opportunity to better understand some of the most important aspects of malaria parasite biology. We were able to generate a draft genome for Hepatocystis sp. using DNA sequencing reads from the blood of a naturally infected red colobus monkey. We provide robust phylogenetic support for Hepatocystis sp. as a sister group to Plasmodium parasites infecting rodents. We show transcriptomic support for a lack of replication in the blood and genomic support for a complete loss of a family of genes involved in red blood cell invasion. Our analyses highlight the rapid evolution of genes involved in parasite vector stages, revealing genes that may be critical for interactions between malaria parasites and mosquitoes.


Assuntos
Apicomplexa/genética , Sangue/parasitologia , Colobus/parasitologia , Malária/veterinária , Doenças dos Macacos/parasitologia , Plasmodium/genética , Infecções Protozoárias em Animais/parasitologia , Animais , Apicomplexa/classificação , Apicomplexa/fisiologia , Genoma de Protozoário , Malária/sangue , Malária/parasitologia , Doenças dos Macacos/sangue , Filogenia , Plasmodium/classificação , Plasmodium/fisiologia , Infecções Protozoárias em Animais/sangue , Transcriptoma
19.
Trends Parasitol ; 36(9): 727-734, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32680786

RESUMO

Despite the benefits of phototrophy, many algae have lost photosynthesis and have converted back to heterotrophy. Parasitism is a heterotrophic strategy, with apicomplexans being among the most devastating parasites for humans. The presence of a nonphotosynthetic plastid in apicomplexan parasites suggests their phototrophic ancestry. The discovery of related phototrophic chromerids has unlocked the possibility to study the transition between phototrophy and parasitism in the Apicomplexa. The chromerid Chromera velia can live as an intracellular parasite in coral larvae as well as a free-living phototroph, combining phototrophy and parasitism in what I call photoparasitism. Since early-branching apicomplexans live extracellularly, their evolution from an intracellular symbiont is unlikely. In this opinion article I discuss possible evolutionary trajectories from an extracellular photoparasite to an obligatory apicomplexan parasite.


Assuntos
Apicomplexa/classificação , Apicomplexa/fisiologia , Evolução Biológica , Parasitos/classificação , Parasitos/fisiologia , Processos Fototróficos , Animais , Apicomplexa/metabolismo , Humanos , Parasitos/metabolismo
20.
Rev Bras Parasitol Vet ; 29(3): e000920, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667500

RESUMO

The aim of this study was to verify the presence and identify the species of haemosporidian parasites in eared doves (Zenaida auriculata) in Brazil. Two hundred and eleven male and female eared doves were trap-captured in four different regions of Londrina city, in southern Brazil. Whole blood was collected in EDTA tubes through heart puncture after euthanasia in a CO2 chamber. A nested PCR targeting the mitochondrial cytochrome b gene (cyt b) of Haemoproteus spp./Plasmodium spp. was performed, followed by an enzymatic digestion to identify the genus. Phylogenetic trees were constructed to determine the closely related species. Out of 211 eared doves, 209 (99.05%) were positive for Haemoproteus spp. and/or Plasmodium spp. RFLP analysis showed that 72.72% (152/209) of eared doves were positive only for Haemoproteus spp., 6.22% (13/209) were positive only for Plasmodium spp., and 21.05% (44/209) of eared doves had mixed infections. Genetic analysis found four samples that were homologous with Haemoproteus multipigmentatus and one that was homologous with Plasmodium sp. This is the first molecular study of hemoparasites from eared doves in Brazil, and it is also the first description of H. multipigmentatus and Plasmodium spp. infection in eared doves in Brazil.


Assuntos
Apicomplexa , Doenças das Aves , Columbidae , Plasmodium , Infecções Protozoárias em Animais , Animais , Apicomplexa/classificação , Apicomplexa/genética , Doenças das Aves/diagnóstico , Doenças das Aves/parasitologia , Brasil , Columbidae/parasitologia , Feminino , Masculino , Filogenia , Plasmodium/classificação , Plasmodium/genética , Reação em Cadeia da Polimerase/veterinária , Infecções Protozoárias em Animais/diagnóstico , Infecções Protozoárias em Animais/parasitologia
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