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1.
Artigo em Inglês | MEDLINE | ID: mdl-38743471

RESUMO

Rhizobia are bacteria that form nitrogen-fixing nodules in legume plants. The sets of genes responsible for both nodulation and nitrogen fixation are carried in plasmids or genomic islands that are often mobile. Different strains within a species sometimes have different host specificities, while very similar symbiosis genes may be found in strains of different species. These specificity variants are known as symbiovars, and many of them have been given names, but there are no established guidelines for defining or naming them. Here, we discuss the requirements for guidelines to describe symbiovars, propose a set of guidelines, provide a list of all symbiovars for which descriptions have been published so far, and offer a mechanism to maintain a list in the future.


Assuntos
Rhizobium , Simbiose , Fabaceae/microbiologia , Guias como Assunto , Fixação de Nitrogênio , Rhizobium/genética , Rhizobium/classificação , Nódulos Radiculares de Plantas/microbiologia
2.
Parasitology ; 151(6): 567-578, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38616408

RESUMO

Trypanosomatids are obligate parasites of animals, predominantly insects and vertebrates, and flowering plants. Monoxenous species, representing the vast majority of trypanosomatid diversity, develop in a single host, whereas dixenous species cycle between two hosts, of which primarily insect serves as a vector. To explore in-depth the diversity of insect trypanosomatids including their co-infections, sequence profiling of their 18S rRNA gene was used for true bugs (Hemiptera; 18% infection rate) and flies (Diptera; 10%) in Cuba. Out of 48 species (molecular operational taxonomic units) belonging to the genera Vickermania (16 spp.), Blastocrithidia (7), Obscuromonas (4), Phytomonas (5), Leptomonas/Crithidia (5), Herpetomonas (5), Wallacemonas (2), Kentomonas (1), Angomonas (1) and two unnamed genera (1 + 1), 38 species have been encountered for the first time. The detected Wallacemonas and Angomonas species constitute the most basal lineages of their respective genera, while Vickermania emerged as the most diverse group. The finding of Leptomonas seymouri, which is known to rarely infect humans, confirms that Dysdercus bugs are its natural hosts. A clear association of Phytomonas with the heteropteran family Pentatomidae hints at its narrow host association with the insect rather than plant hosts. With a focus on multiple infections of a single fly host, using deep Nanopore sequencing of 18S rRNA, we have identified co-infections with up to 8 trypanosomatid species. The fly midgut was usually occupied by several Vickermania species, while Herpetomonas and/or Kentomonas species prevailed in the hindgut. Metabarcoding was instrumental for analysing extensive co-infections and also allowed the identification of trypanosomatid lineages and genera.


Assuntos
Coinfecção , Filogenia , RNA Ribossômico 18S , Trypanosomatina , Trypanosomatina/genética , Trypanosomatina/classificação , Trypanosomatina/isolamento & purificação , Animais , Cuba/epidemiologia , RNA Ribossômico 18S/genética , RNA Ribossômico 18S/análise , Coinfecção/parasitologia , Dípteros/genética , Hemípteros/parasitologia , Hemípteros/genética , DNA de Protozoário/genética , DNA de Protozoário/análise
3.
Microorganisms ; 11(9)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37764139

RESUMO

A relevant aspect in the epidemiology of Tegumentary Leishmaniasis (TL) are the Leishmania parasites carrying a viral endosymbiont, Leishmania RNA Virus 1 (LRV1), a dsRNA virus. Leishmania parasites carrying LRV1 are prone to causing more severe TL symptoms, increasing the likelihood of unfavorable clinical outcomes. LRV1 has been observed in the cultured strains of five L. (Viannia) species, and host specificity was suggested when studying the LRV1 from L. braziliensis and L. guyanensis strains. The coevolution hypothesis of LRV1 and Leishmania was based on phylogenetic analyses, implying an association between LRV1 genotypes, Leishmania species, and their geographic origins. This study aimed to investigate LRV1 specificity relative to Leishmania (Viannia) species hosts by analyzing LRV1 from L. (Viannia) species. To this end, LRV1 was screened in L. (Viannia) species other than L. braziliensis or L. guyanensis, and it was detected in 11 out of 15 L. naiffi and two out of four L. shawi. Phylogenetic analyses based on partial LRV1 genomic sequencing supported the hypothesis of host specificity, as LRV1 clustered according to their respective Leishmania species' hosts. These findings underscore the importance of investigating Leishmania and LRV1 coevolution and its impact on Leishmania (Viannia) species dispersion and pathogenesis in the American Continent.

4.
Neotrop Entomol ; 52(5): 802-813, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37495766

RESUMO

Numerous staphylinid species can be found in termite nests. While the distributional range of termite hosts has been well studied, the same cannot be said for their associated fauna. There is a lack of comprehensive sampling even in areas where termite fauna has been well-sampled. In recent surveys in Southeastern Brazil, we collected a new species of termitophilous rove beetle from the tribe Termitohospitini (Aleocharinae): Termitosocius boraceiensis sp. nov., is herein described. The new species is the first termitophile found in Boracéia, SP, Brazil, even with decades of termite sampling in the place. Additionally, we discuss the diversity and description rate of neotropical Termitohospitini, and investigate the potential of cospeciation between termites and their termitophilous beetles on the Emerson-Kistner principle. Our findings suggest that the neotropical Termitohospitini may be more diverse than previously believed and that Termitosocius species are present in host species that are geographically separated, implying a cospeciation scenario. Additional sampling is required to fully comprehend the relationships between termitophiles and their termite hosts. The outcomes of this study provide new insights into the undersampling scenario and possibly cospeciation between termites and their termitophiles in the Neotropical region.


Assuntos
Besouros , Isópteros , Animais , Brasil , Especificidade de Hospedeiro , Inquéritos e Questionários
5.
Int J Mol Sci ; 24(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37298511

RESUMO

The genetically related assemblages of the intestinal protozoa parasite Giardia lamblia are morphologically indistinguishable and are often derived from specific hosts. The Giardia assemblages are separated by large genetic distances, which might account for their relevant biological and pathogenic differences. In this work, we analyzed the RNAs cargo released into exosomal-like vesicles (ElVs) by the assemblages A and B, which differentially infect humans, and the assemblage E, which infects hoofed animals. The RNA sequencing analysis revealed that the ElVs of each assemblage contained distinct small RNA (sRNA) biotypes, suggesting a preference for specific packaging in each assemblage. These sRNAs were classified into three categories, ribosomal-small RNAs (rsRNAs), messenger-small RNAs (msRNAs), and transfer-small RNAs (tsRNAs), which may play a regulatory role in parasite communication and contribute to host-specificity and pathogenesis. Uptake experiments showed, for the first time, that ElVs were successfully internalized by the parasite trophozoites. Furthermore, we observed that the sRNAs contained inside these ElVs were first located below the plasma membrane but then distributed along the cytoplasm. Overall, the study provides new insights into the molecular mechanisms underlying the host-specificity and pathogenesis of G. lamblia and highlights the potential role of sRNAs in parasite communication and regulation.


Assuntos
Exossomos , Giardíase , Parasitos , Humanos , Animais , Giardia/genética , RNA/metabolismo , Exossomos/genética , Exossomos/metabolismo , Giardíase/parasitologia , RNA de Transferência/metabolismo , RNA Ribossômico/metabolismo
6.
Microorganisms ; 11(4)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37110377

RESUMO

Ralstonia solanacearum species complex (RSSC) cause several phytobacteriosis in many economically important crops around the globe, especially in the tropics. In Brazil, phylotypes I and II cause bacterial wilt (BW) and are indistinguishable by classical microbiological and phytopathological methods, while Moko disease is caused only by phylotype II strains. Type III effectors of RSSC (Rips) are key molecular actors regarding pathogenesis and are associated with specificity to some hosts. In this study, we sequenced and characterized 14 newly RSSC isolates from Brazil's Northern and Northeastern regions, including BW and Moko ecotypes. Virulence and resistance sequences were annotated, and the Rips repertoire was predicted. Confirming previous studies, RSSC pangenome is open as α≅0.77. Genomic information regarding these isolates matches those for R. solanacearum in NCBI. All of them fit in phylotype II with a similarity above 96%, with five isolates in phylotype IIB and nine in phylotype IIA. Almost all R. solanacearum genomes in NCBI are actually from other species in RSSC. Rips repertoire of Moko IIB was more homogeneous, except for isolate B4, which presented ten non-shared Rips. Rips repertoire of phylotype IIA was more diverse in both Moko and BW, with 43 common shared Rips among all 14 isolates. New BW isolates shared more Rips with Moko IIA and Moko IIB than with other public BW genome isolates from Brazil. Rips not shared with other isolates might contribute to individual virulence, but commonly shared Rips are good avirulence candidates. The high number of Rips shared by new Moko and BW isolates suggests they are actually Moko isolates infecting solanaceous hosts. Finally, infection assays and Rips expression on different hosts are needed to better elucidate the association between Rips repertoire and host specificities.

7.
Med Vet Entomol ; 37(3): 511-522, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37000587

RESUMO

Host specificity of fleas affects their biodiversity that plays a major role in determining the potential transmission routes by pathogens through vertebrate hosts, including humans. In the Biogeographic Andean region, numerous systematic and ecological studies have been conducted, revealing a high diversity of flea taxa of mammals and the presence of pathogenic organisms transmitted by fleas; however, the degree of preference with which each flea species associates with a mammal host remains poorly understood in this region. Herein, host specificity in mammal fleas from the Andean region was analysed. We employed the number of host species for each flea species and the index of host specificity STD *. Following the literature, 144 species and 13 subspecies of fleas (31 genera and 10 families) have been described in the Andean biogeographic region; 76 taxa are endemic to this region. To carry out the analyses of host specificity, we considered 1759 records of fleas collected from 124 species and 59 genera of wild and domestic mammals, mostly rodent species (85.9%). Our results indicate that typical Andean fleas are genus or family host specific (mostly STD * less than 3.0). More diverse mammal hosts are parasitized by more diverse flea genera and families and these hosts are phylogenetically related. Otherwise, these hosts are associated with different flea lineages, suggesting the interaction of ecological and evolutionary mechanisms (host-switching, ecological adaptations and co-evolutionary alternation). The fields of disease ecology and One Health are considering the host specificity of arthropod vectors as an important point to understand the mechanisms of emergence and re-emergence of diseases. Our results allow us to estimate the risk of diseases involving fleas in the Andean region.


Assuntos
Infestações por Pulgas , Parasitos , Doenças dos Roedores , Sifonápteros , Humanos , Animais , Especificidade de Hospedeiro , Mamíferos/parasitologia , Infestações por Pulgas/parasitologia , Infestações por Pulgas/veterinária , Roedores , Doenças dos Roedores/parasitologia
8.
Braz J Microbiol ; 53(4): 1745-1759, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35841534

RESUMO

Phytopathogenic strains of Fusarium oxysporum Schlecht exhibit clear host specificity, which appears to be a persistent characteristic and a dependable base for the forma specialis system of these pathogens. Here, we report an altered host specificity of the F. oxysporum f.sp. radicis-cucumerinum strain V03-2 g (Forc V03-2 g) - a causative agent of cucumber root-rot, the clonal derivates of which acquired the ability to infect tomato plants. Since the clonal derivates of Forc V03-2 g with transformed host specificity preserved their ability to parasitize on cucumber plants, the changes that occurred can be classified as broadening of host specificity. To our knowledge, this is the first observation of pathogenicity changes in formae speciales of F. oxysporum. The clonal derivates acquired could be used to trace genetic determinants of the host specificity of phytopathogenic strains of F. oxysporum.


Assuntos
Cucumis sativus , Fusarium , Solanum lycopersicum , Especificidade de Hospedeiro , Doenças das Plantas/microbiologia , Fusarium/genética , Plantas/microbiologia
9.
J Eukaryot Microbiol ; 69(3): e12902, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35279911

RESUMO

Speciation is a complex and continuous process that makes the delineation of species boundaries a challenging task in particular in species with little morphological differentiation, such as parasites. In this case, the use of genomic data is often necessary, such as for the intracellular Microsporidian parasites. Here, we characterize the genome of a gut parasite of the cladoceran Daphnia longispina (isolate FI-F-10), which we propose as a new species within the genus Ordospora: Ordospora pajunii sp. nov (Ordosporidae). FI-F-10 closest relative, Ordospora colligata is only found in D. magna. Both microsporidian species share several morphological features. Although it is not possible to estimate divergence times for Microsporidia due to the lack of fossil records and accelerated evolutionary rates, we base our proposal on the phylogenomic and genomic distances between both microsporidian lineages. The phylogenomic reconstruction shows that FI-F-10 forms an early diverging branch basal to the cluster that contains all known O. colligata strains. Whole-genome comparisons show that FI-F-10 presents a greater divergence at the sequence level than observed among O. colligata strains, and its genomic average nucleotide identity (ANI) values against O. colligata are beyond the intraspecific range previously established for yeast and prokaryotes. Our data confirm that the ANI metrics are useful for fine genetic divergence calibration across Microsporidia taxa. In combination with phylogenetic and ecological data, genome-based metrics provide a powerful approach to delimitate species boundaries.


Assuntos
Microsporídios , Parasitos , Animais , Daphnia/genética , Daphnia/parasitologia , Genômica , Microsporídios/genética , Filogenia
10.
Dis Aquat Organ ; 147: 33-46, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34789586

RESUMO

The system formed by a still-unidentified rhizocephalan infecting the Patagonian stone crab Danielethus (Platyxanthus) patagonicus (A. Milne-Edwards, 1879) was analyzed in northern Patagonia. Out of 3222 crabs sampled, mean prevalence of externae was 2.1%, while corrected mean prevalence based on observations of externae, scars or other indicators of infection was slightly higher (3.01%; N = 2100). Prevalence was higher in males (4.47%) than in females (1.44%). Parasitized males were morphologically feminized, while females showed no hyper-feminization. Although most parasitized crabs showed only 1 externa, 2 externae were observed in some individuals. The parasite externae were only present in intermediate-sized crabs (26.6-99.7 cm carapace width). While scanning electron microscopy images allowed detection of the 'smooth-surface-balloon' type of retinacula on the inner surface of the externae, typical of the Sacculinidae and Peltogastridae, the position of the mantle opening relative to the stalk, the receptacle location and the shape of the externae suggest that the parasite belongs to either the genus Sacculina or to the recently erected Parasacculina (Polyascidae).


Assuntos
Braquiúros , Parasitos , Animais , Feminino , Interações Hospedeiro-Parasita , Masculino
11.
BMC Ecol Evol ; 21(1): 190, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34670486

RESUMO

BACKGROUND: In parasitism arm race processes and red queen dynamics between host and parasites reciprocally mold many aspects of their genetics and evolution. We performed a parallel assessment of population genetics and demography of two species of pinworms with different degrees of host specificity (Trypanoxyuris multilabiatus, species-specific; and T. minutus, genus-specific) and their host, the mantled howler monkey (Alouatta palliata), based on mitochondrial DNA sequences and microsatellite loci (these only for the host). Given that pinworms and primates have a close co-evolutionary history, covariation in several genetic aspects of their populations is expected. RESULTS: Mitochondrial DNA revealed two genetic clusters (West and East) in both pinworm species and howler monkeys, although population structure and genetic differentiation were stronger in the host, while genetic diversity was higher in pinworms than howler populations. Co-divergence tests showed no congruence between host and parasite phylogenies; nonetheless, a significant correlation was found between both pinworms and A. palliata genetic pairwise distances suggesting that the parasites' gene flow is mediated by the host dispersal. Moreover, the parasite most infective and the host most susceptible haplotypes were also the most frequent, whereas the less divergent haplotypes tended to be either more infective (for pinworms) or more susceptible (for howlers). Finally, a positive correlation was found between pairwise p-distance of host haplotypes and that of their associated pinworm haplotypes. CONCLUSION: The genetic configuration of pinworm populations appears to be molded by their own demography and life history traits in conjunction with the biology and evolutionary history of their hosts, including host genetic variation, social interactions, dispersal and biogeography. Similarity in patterns of genetic structure, differentiation and diversity is higher between howler monkeys and T. multilabiatus in comparison with T. minutus, highlighting the role of host-specificity in coevolving processes. Trypanoxyuris minutus exhibits genetic specificity towards the most frequent host haplotype as well as geographic specificity. Results suggest signals of potential local adaptation in pinworms and further support the notion of correlated evolution between pinworms and their primate hosts.


Assuntos
Alouatta , Enterobíase , Oxyuroidea , Alouatta/genética , Animais , Enterobius
12.
Pathogens ; 10(7)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34357999

RESUMO

Blood flukes are digeneans that infect wild and farmed fish that can cause a severe and potentially lethal disease in farmed fish. These parasites are undetectable in the larval stage based on macroscopic observations in the definitive host with the infection becoming evident when eggs accumulate in the branchial vessels. There are nine known species of the genus Paradeontacylix and seven exclusively parasitize Seriola spp. from several geographical areas. Seriola lalandi aquaculture farms are emerging at various localities in northern Chile. Here, we report, for the first time, two blood fluke species parasitizing S. lalandi in the Southeastern Pacific (Chile). In the laboratory, the gills and heart of fish were removed. The retained blood flukes were separated according to the infection site, fixed in 70% or 95% ethanol for taxonomic and molecular analysis, respectively. Morphometrical differences among the fluke species were evaluated with a principal component analysis (PCA) using proportional body measurements. Phylogenetic trees were constructed based on 28S rDNA, cox1 mDNA using Bayesian inference (BI), and maximum likelihood (ML). Based on morphology, morphometry, and molecular analyses, two new species are proposed: P. humboldti n. sp. from the gills and P. olivai n. sp. from the heart of S. lalandi. Both were clearly distinguished from other species of Paradeontacylix by a combination of morphologic features (posterior tegumental spines, testes arrangement, body size). The genetic distance (based on cox1) among species was >10%. P. humboldti n. sp. and P. olivai n. sp. are sister species (with a common ancestor) independent of P. godfreyi from S. lalandi in Australia. The newly identified parasites may pose a risk to farmed S. lalandi as aporocotylids have been the cause of diseases in farmed fish from other geographical areas. In addition, some cages of S. lalandi are currently maintained in an open circulating system, which could favor the transmission of these parasites (if involved hosts are present in the environment).

13.
Biodivers Data J ; 9: e68598, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34393585

RESUMO

BACKGROUND: We revise the genus Metaplagia Coquillett, 1895 and describe five new species from Area de Conservación Guanacaste (ACG) in northwestern Costa Rica. All new species were reared from an ongoing inventory of wild-caught caterpillars spanning a variety of species within the family Sphingidae (Lepidoptera: Sphingidae). Our study provides a concise description of each new species using morphology, life history, molecular data and photographic documentation. In addition to the new species, the authors provide a re-description of the genus and a revised key to the species of Metaplagia. NEW INFORMATION: The following five new species of Metaplagia are described: Metaplagia leahdennisae Fleming & Wood sp. n., Metaplagia lindarobinsonae Fleming & Wood sp. n., Metaplagia paulinesaribasae Fleming & Wood sp. n., Metaplagia robinsherwoodae Fleming & Wood sp. n. and Metaplagia svetlanakozikae Fleming & Wood sp. n.The following is proposed by Fleming & Wood as new combination of Plagiomima Brauer & Bergenstamm, 1891: Plagiomima latifrons (Reinhard, 1956) comb. n.

14.
Parasitol Res ; 120(6): 1965-1977, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33851247

RESUMO

Procamallanus is a species-rich genus of parasitic nematodes of marine, brackish, and freshwater fishes, occurring also occasionally in amphibians and reptiles. In the Neotropical region, this genus is highly diverse, with species described from a wide range of fish families. In this study, we reassess the taxonomic status of Procamallanus rebecae with molecular and morphological data and describe a new species endemic to Nicaragua and Costa Rica. We analyzed all Procamallanus isolated from fish from the Nicaraguan lakes and some rivers in Costa Rica after an exhaustive analysis of their freshwater fish endoparasite fauna. Procamallanus rebecae is a host-specific parasite of Middle American cichlids, previously reported in southern Mexico, Nicaragua, and Costa Rica. We therefore compared these Central American specimens with individuals of P. rebecae collected in cichlids from southeastern Mexico using two genomic regions (28S rDNA and mitochondrial cytochrome oxidase subunit 1, COI). We found high levels of sequence divergence between Procamallanus from the two geographical regions, with up to 9.8 and 10.5% for both genetic markers, respectively. We also analyzed their morphology and found conspicuous differences in the shape of the mouth and the structure of the female cauda. We therefore describe the specimens of Procamallanus from Central American cichlids as a new species. Both Procamallanus species occur in different cichlid species and are allopatrically distributed. The host specificity and ancient association patterns between cichlids and Procamallanus and the jointly colonization of both hosts and parasites during their northern dispersal from South America are briefly discussed.


Assuntos
Ciclídeos/parasitologia , Infecções por Spirurida/veterinária , Espirurídios/classificação , Animais , Costa Rica/epidemiologia , DNA Ribossômico/genética , Feminino , Nematoides/classificação , Nicarágua/epidemiologia , Filogenia , Especificidade da Espécie , Espirurídios/genética , Infecções por Spirurida/epidemiologia , Infecções por Spirurida/parasitologia , Estados Unidos
15.
New Phytol ; 229(1): 488-500, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32852846

RESUMO

Wheat blast caused by the Triticum pathotype of Pyricularia oryzae poses a serious threat to wheat production in South America and Asia and is now becoming a pandemic disease. Here, we show that Rmg8, a promising wheat gene for resistance breeding, is suppressed by PWT4, an effector gene of P. oryzae, and in turn that the suppression is counteracted by Rwt4, a wheat gene recognizing PWT4. When PWT4 was introduced into a wheat blast isolate carrying AVR-Rmg8 (an avirulence gene corresponding to Rmg8), PWT4 suppressed wheat resistance conferred by Rmg8. PWT4 did not alter the expression of AVR-Rmg8, but higher expression of PWT4 led to more efficient suppression. This suppression was observed in rwt4 carriers, but not in Rwt4 carriers, indicating that it is counteracted by Rwt4. PWT4 was assumed to have been horizontally transferred from a weed-associated cryptic species, P. pennisetigena, to an Avena isolate of P. oryzae in Brazil. This implies a potential risk of the acquisition of PWT4 by the wheat blast fungus and the 'breakdown' of Rmg8. We suggest that Rmg8 should be introduced together with Rwt4 into a wheat cultivar when it is used for resistance breeding.


Assuntos
Magnaporthe , Oryza , Ascomicetos , Ásia , Brasil , Especificidade de Hospedeiro , Melhoramento Vegetal , Doenças das Plantas/genética , Triticum/genética
16.
Front Microbiol ; 12: 771589, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095792

RESUMO

Sponge-associated microorganisms are essential for sponge survival. They play an important role in recycling nutrients and, therefore, in the maintenance of the ecosystem. These microorganisms are diverse, species-specific, and different from those in the surrounding seawater. Bacterial sponge symbionts have been extensively studied in the tropics; however, little is known about these microorganisms in sponges from high-latitude environments. Sponges can cover up to 80% of the benthos in Antarctica and are crucial architects for the marine food web. In this study, we present analyses of the bacterial symbionts of three sponges: Haliclona (Rhizoniera) sp., Hymeniacidon torquata, and Isodictya kerguelenensis from the Western Antarctic Peninsula (WAP) with the aim to determine variations on the specificity of the bacteria-sponge interactions and potential signatures on their predicted functional profiles. We use high-throughput 16S rRNA gene sequencing of 30 sponge individuals inhabiting South Bay (Palmer Archipelago, WAP) to describe their microbiome taxonomy and diversity and predict potential functional profiles based on this marker gene. Our work shows similar bacterial community composition profiles among the same sponge species, although the symbiotic relationship is not equally conserved among the three Antarctic sponges. The number of species-specific core operational taxonomic units (OTUs) of these Antarctic sponges was low, with important differences between the total abundance accounted for these OTUs. Only eight OTUs were shared between the three sponge species. Analyses of the functional potential revealed that despite the high host-symbiont specificity, the inferred functions are conserved among these microbiomes, although with differences in the abundance of specific functions. H. torquata showed the highest level of intra-specificity and a higher potential of pathways related to energy metabolism, metabolisms of terpenoids and polyketides, and biosynthesis of other secondary metabolites. Overall, this work shows variations in the specificity of the sponge-associated bacterial communities, differences in how hosts and symbionts establish their relations, and in their potential functional capabilities.

17.
Microbiol Res ; 244: 126667, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33338969

RESUMO

It is known that different plant species select specific microbes to live inside their tissues in a process determined by the host genotype, phenotype and geographic location, which can introduce discussion on plant endemism and the assembly of specific microbial communities. Herein, we report the results of an investigation relating the geographic distribution of plant species and the composition of microbial communities associated with plant hosts. The bacterial and fungal community associated with Anthurium plant leaves was mapped to assess the diversity and ecology of the endophytic community associated with Anthurium spp. collected on islands and on the Brazilian mainland. Twenty-six Anthurium specimens were surveyed, distributed throughout the São Paulo state coastline, including Alcatrazes Island, some coastal islands and distinct mainland environments. Bacterial and fungal endophytes were obtained from the leaves of A. alcatrazense, A. loefgrenii, A. penthaphyllum, A. urvellianum and A. intermedium and subjected to massive bacterial 16S rRNA and fungal ITS sequencing. The results indicated that A. alcatrazense, endemic to Alcatrazes Island, hosted a specific bacterial community structure, while its fungal community was similar to that of Anthurium species from other locations. Betaproteobacteria showed a high differential occurrence in A. alcatrazense. Some groups of fungi were found mainly inhabiting A. loefgrenii plants. While Alphaproteobacteria, Gammaproteobacteria, Actinobacteria and Sordariomycetes, Dothiodeomycetes and Tremellomycetes composed the core microbial community among Anthurium plants. The results suggest crucial role for the bacterial communities to endemic plants, while endophytic fungal diversity is less specifically distributed among endemic and nonendemic plant species.


Assuntos
Araceae/microbiologia , Bactérias/isolamento & purificação , Fungos/isolamento & purificação , Microbiota , Micobioma , Bactérias/classificação , Bactérias/genética , Biodiversidade , Brasil , Fungos/classificação , Fungos/genética , Folhas de Planta/microbiologia
18.
J Adv Vet Anim Res ; 7(3): 482-500, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33005675

RESUMO

Captive birds in zoological settings often harbor parasites, but little information is available about the potential for free-ranging avifauna to act as a source of infection. This review summarizes the gastrointestinal parasites found in zoo birds globally and in seven common free-ranging avian species [mallard (Anas platyrhynchos), Eurasian blackbird (Turdus merula), common starling (Sturnus vulgaris), Eurasian jackdaw (Corvus monedula), house sparrow (Passer domesticus), European robin (Erithacus rubecula), and rock dove (Columba livia)] to identify the overlap and discuss the potential for cross-species transmission. Over 70 references were assessed, and papers spanned over 90 years from 1925 to 2019. A total of 60 studies from 1987 to 2019 met the eligibility criteria. All examined free-ranging avifauna harbored parasite species that were also reported in zoo birds, except for the European jackdaw. Parasites reported in captive and free-ranging birds include nematodes (Capillaria caudinflata, Dispharynx nasuta, Ornithostrongylus quadriradiatus, Strongyloides avium, Syngamus trachea, and Tetrameres fissispina), cestodes (Dicranotaenia coronula, Diorchis stefanskii, Fimbriaria fasciolaris, and Raillietina cesticillus, Sobolevicanthus gracilis), trematode (Echinostoma revolutum), and protozoa (Cryptosporidium baileyi). Although no study effectively proved cross-transmission either experimentally or by genetic analysis, these parasites demonstrate low host specificity and a high potential for parasite sharing. There is potential for parasite sharing whenever determinants such as host specificity, life cycle, and husbandry are favorable. More research should be carried out to describe parasites in both captive and free-ranging birds in zoological settings and the likelihood of cross-infection. Such information would contribute to evidence-based control measures, enhancing effective husbandry and preventive medicine protocols.

19.
Int J Parasitol ; 50(10-11): 899-919, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32750362

RESUMO

Fish parasites from the isopod family Cymothoidae have, in recent years, received increased global attention due to both their ecological and economic importance. This is particularly true for the buccal inhabiting genus Ceratothoa Dana, 1852, whose members have been implicated in negatively impacting the health of both farmed and wild-caught fishes. As research on this group increases, so does our understanding of their host specificity and distribution. The aims of this paper were thus to review the current distribution and host records of Ceratothoa and describe a new species, Ceratothoa springbok n. sp. from South Africa. Including the new species described here, there are currently 25 accepted Ceratothoa spp. known from eight of the 12 marine biogeographical realms of the world. The majority of Cymothoidae species are known to occur in the tropical realms, whereas our analyses show that the greatest diversity of Ceratothoa spp. can be found in temperate realms. These results indicate the possibility that Ceratothoa is more diverse in temperate regions. This review also highlights the low diversity of Ceratothoa from the oceans around both North and South America. Current records indicate that species of Ceratothoa parasitise 108 fish species in 76 genera and 41 families. Eleven Ceratothoa spp. demonstrate host specificity up to host genus or family level. Amongst the hosts, members of the Sparidae are parasitised by 13 species of Ceratothoa, making it the host family with the highest diversity of parasites from this genus. The new species, C. springbok n. sp., also parasitises a sparid and was found in the buccal cavity of the carpenter seabream, Argyrozona argyrozona. This new species, the largest of all recorded Ceratothoa (up to 65 mm) and amongst the largest of all Cymothoidae, is characterised by its truncate and ventrally folded frontal margin, pereonite 1 with medial indentations, the wide anterolateral margins of pereonite 1 with an inwardly produced point, and a well-developed carina on the basis of pereopod 7. A key to the southern African Ceratothoa is provided.


Assuntos
Doenças dos Peixes , Peixes/parasitologia , Isópodes , Animais , Doenças dos Peixes/parasitologia , Especificidade de Hospedeiro , Isópodes/patogenicidade , África do Sul , América do Sul
20.
Biodivers Data J ; 8: e47157, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32390755

RESUMO

BACKGROUND: We describe 25 new species in the genus Telothyria van der Wulp, 1890 from Area de Conservación Guanacaste (ACG) in northwestern Costa Rica. All species herein described were reared from an ongoing inventory of wild-caught caterpillars spanning two families (Lepidoptera: Crambidae, and Tortricidae). Our study provides a concise description of each new species using morphology, life history, molecular data, and photographic documentation; a redescription of the genus, and its type species as well as a revised key to species of Telothyria occurring in the Mesoamerican region. We also suggest seven new synonymies resulting in 11 new combinations. NEW INFORMATION: The following 25 new species of Telothyria are described: T. aidani sp. n., T. alexanderi sp. n., T. auranticrus sp. n., T. auriolus sp. n., T. bicuspidata sp. n., T. carolinacanoae sp. n., T. clavata sp. n., T. cristata sp. n., T. diniamartinezae sp. n., T. duniagarciae sp. n., T. duvalierbricenoi sp. n., T. eldaarayae sp. n., T. erythropyga sp. n., T. fimbriata sp. n., T. fulgida sp. n., T. gloriashihezarae sp. n., T. grisea sp. n., T. harryramirezi sp. n., T. incisa sp. n., T. manuelpereirai sp. n., T. obscura sp. n., T. omissa sp. n., T. osvaldoespinozai sp. n., T. peltata sp. n., and T. ricardocaleroi sp. n.The following are proposed by Fleming & Wood as new generic synonyms of Telothyria: Comatacta Coquillett Syn. n., Floradalia Thompson Syn. n., Ptilomyia Curran Syn. n., Ptilomyiopsis Townsend Syn. n., Ptilomyoides Curran Syn. n., Euptilomyia Syn. n., Eutelothyria Townsend Syn. n.The following new combinations are proposed as a result of the new synonymies: Telothyria bequaerti (Curran, 1925) Comb. n., Telothyria cruenta (Giglio-Tos, 1893) Comb. n., Telothyria frontalis (Townsend, 1939) Comb. n., Telothyria insularis (Curran, 1927) Comb. n., Telothyria itaquaquecetubae (Townsend, 1931) Comb. n., Telothyria major (Thompson, 1963) Comb. n., Telothyria micropalpus (Curran, 1925) Comb. n., Telothyria minor (Thompson, 1963) Comb. n., Telothyria nautlana (Townsend, 1908) Comb. n., Telothyria plumata (Curran, 1925) Comb. n., Telothyria trinitatis (Thompson, 1963) Comb. n., Telothyria variegata (Fabricius, 1805) Comb. n. Musca tricincta Fabricius is synonymized under Telothyria variegata Fabricius, Syn. n. Telothyria schineri Fleming & Wood nom. n. is proposed as a replacement name for Miltogramma brevipennis Schiner.Additionally we provide redescriptions of two previously named species: the type species Telothyria cupreiventris (van der Wulp) due to its being the type species, and Telothyria relicta (van der Wulp) due to its having been reared as an outcome of the inventory.

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