RESUMO
Sea urchins have a wide variety of symbionts on their body surfaces and inside their bodies. Copepods of the genus Clavisodalis (Taeniacanthidae) collected from the esophagus of sea urchins of the genera Diadema and Echinothrix in southern Japan were identified based on their morphological characteristics, and molecular analysis was conducted to determine whether genetic variation occurs in copepods from different localities and hosts. Morphological observations identified individuals from southern Japan as Clavisodalis sentifer Dojiri and Humes, 1982, making this the first record of this species in the northern hemisphere and the first record of its genus in Japan. Morphological and molecular analysis suggested that the copepod specimens collected from multiple hosts across two genera would be the same species. Considering the typically observed high level of host specificity among taeniacanthid copepods, the utilization of hosts from two genera by C. sentifer is noteworthy.
Assuntos
Copépodes , Ouriços-do-Mar , Animais , Copépodes/genética , Copépodes/anatomia & histologia , Copépodes/fisiologia , Ouriços-do-Mar/genética , Ouriços-do-Mar/parasitologia , Oceano Pacífico , Filogenia , Japão , Especificidade de HospedeiroRESUMO
Marine planktonic ciliates are largely oligotrichs and choreotrichs, which are two subclasses of the class Spirotrichea. The current phylogenetic assignments of oligotrichs and choreotrichs are inconsistent with previous results based on morphological features, probably hindered by the limited information from a single gene locus. Here we provide 53 new sequences from small subunit ribosomal RNA (SSU rDNA), ITS1-5.8S rDNA-ITS2, and large subunit ribosomal RNA (LSU rDNA) gene loci in 25 oligotrich and choreotrich species. We also predict RNA secondary structures for the ITS2 regions in 55 species, 48 species of which are reported for the first time. Based on these novel data, we make a more comprehensive phylogenetic reconstruction, revealing consistency between morphological taxonomy and an updated phylogenetic system for oligotrichs and choreotrichs. With the addition of data from ciliature patterns and genes, the phylogenetic analysis of the subclass Oligotrichia suggests three evolutionary trajectories, among which: 1) Novistrombidium asserts an ancestral ciliary pattern in Oligotrichia; 2) the subgenera division of Novistrombidium and Parallelostrombidium are fully supported; 3) the three families (Tontoniidae, Pelagostrombidiidae and Cyrtostrombidiidae) all evolved from the most diverse family Strombidiidae, which explains why strombidiids consistently form polyphyletic clades. In the subclass Choreotrichia, Strombidinopsis likely possesses an ancestral position to other choreotrichs, and both phylogenetic analysis and RNA secondary structure prediction support the hypothesis that tintinnids may have evolved from Strombidinopsis. The results presented here offer an updated hypothesis for the evolutionary history of oligotrichs and choreotrichs based on new evidence obtained by expanding sampling of molecular information across multiple gene loci.
Assuntos
Cilióforos , Humanos , Filogenia , Cilióforos/genética , DNA Ribossômico , RNA , RNA RibossômicoRESUMO
Tobacco target leaf spot is a leaf disease that seriously affects both the quantity and quality of commercial tobacco crops and has caused huge economic losses in many countries and also pandemics in China since 2006. The anastomosis group-3 (AG-3) pathogen is divided into different subgroups namely AG-3 PT (potato type), AG-3TB (tobacco type), and AG-3 TM (tomato type), based on their host and the combined data from the ribosomal DNA internal transcribed spacer (rDNA-ITS), rDNA intergenic spacer 1 (rDNA-IGS1) regions, and translation elongation factor 1-α (tef-1α) gene. In this study, we collected tobacco leaves showing target spot symptom from four fields in China. We obtained 49 isolates from southwest China (Yunnan Provinces) and six isolates from northeast China (Liaoning Province). Phylogenetic tree based on rDNA-ITS region indicated that 51 isolates (49 isolates from Yunnan and two isolates from Liaoning) and 4 isolates from Liaoning belonged to AG-3 TB and AG-3 TM, respectively.
Assuntos
Nicotiana , Filogenia , China , DNA Ribossômico/genéticaRESUMO
BACKGROUND: The aim of this study was to identified cyst nematodes in the cabbage production areas in Nigde Province by molecular methods to underpin decision making for field control. The sequences of ribosomal DNA region (rDNA-ITS) and cytochrome oxidase subunit 1 (mtDNA-COI) were used for the first time for identification Heterodera cruciferae (cabbage cyst nematode) in Turkey. METHODS AND RESULTS: Heterodera cruciferae populations extracted from cabbage growing areas of Nigde Province and investigated using sequences of rDNA-ITS and mtDNA-COI. Similarities and differences between 13 geographic populations of H. cruciferae were detected in surveys during 2020-2021. DNA from single cysts was successfully amplified, and genetic variability was revealed within nematode populations. Based on these results, H. cruciferae is reported for the first time from Nigde Province, Turkey. This study showed clear discrimination among the sampled populations of H. cruciferae. CONCLUSION: This finding is important for control and managing cabbage cyst nematode in cabbage fields in Turkey as more than one Heterodera spp. can occur. Future studies should investigate the population dynamics and control of H. cruciferae in fields in the sampled districts.
Assuntos
Brassica , Cistos , Tylenchoidea , Animais , Brassica/genética , Turquia , Tylenchoidea/genética , DNA Mitocondrial/genética , DNA RibossômicoRESUMO
Oxyurid nematodes (Syphacia spp.) from bank (Myodes glareolus) and field/common (Microtus spp.) voles, from disparate geographical sites in the British Isles, were examined morphologically and genetically. The genetic signatures of 118 new isolates are provided, based primarily on the rDNA internal transcribed spacers (ITS1-5.8S-ITS2) region and for representative isolates also on the small subunit 18S rDNA region and cytochrome c oxidase subunit 1 (cox-1) gene locus. Genetic data on worms recovered from Microtus spp. from the European mainland and from other rodent genera from the Palaearctic, North America and West Africa are also included. We test historical hypotheses indicating that S. nigeriana is a generalist species, infecting a range of different rodent genera. Our results establish that S. nigeriana is a parasite of both bank and field voles in the British Isles. An identical genotype was also recorded from Hubert's multimammate mouse (Mastomys huberti) from Senegal, but Mastomys spp. from West Africa were additionally parasitized by a related, although genetically distinct Syphacia species. We found no evidence for S. petrusewiczi in voles from the British Isles but isolates from Russia and North America were genetically distinct and formed their own separate deep branch in maximum likelihood molecular phylogenetic trees.
Assuntos
Nematoides , Oxyuroidea , Doenças dos Roedores , Animais , Arvicolinae/parasitologia , Camundongos , Oxyuroidea/genética , Filogenia , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/parasitologiaRESUMO
Balantioides coli is the only known zoonotic ciliate that can infect humans and is usually acquired from swine. It has, however, been reported in other mammals, including guinea pigs, where infection prevalence and molecular characterization are relatively unknown. In the present study, 32 guinea pigs from two different pet markets in Luoyang city of the Henan province in China were evaluated for ciliate-like trophozoites or cysts by direct fecal smear microscopy. Positive samples were further characterized using 18S rDNA and ITS1-5.8S rDNA-ITS2 sequence analysis. Microscopy indicated that ciliate-like cysts were observed in the fecal samples of several guinea pigs, were spherical in shape, and exhibited sizes of 40-65 µm in diameter. The average cyst-positive prevalence in guinea pigs was 62.5%. Sequence analysis indicated that the guinea pig-derived ciliate isolates belonged to B. coli and included two genetic variants (A and B), of which genetic variant A was more dominant among the guinea pig samples. To the best of our knowledge, the present study is the first molecular identification of B. coli in guinea pigs and provides some important information for investigating the molecular epidemiology of B. coli.
Assuntos
Balantidíase/veterinária , Cobaias/parasitologia , Animais de Estimação/parasitologia , Doenças dos Roedores/parasitologia , Trichostomatina/isolamento & purificação , Animais , Balantidíase/epidemiologia , Balantidíase/parasitologia , China/epidemiologia , DNA de Protozoário/genética , DNA Ribossômico/genética , Fezes/parasitologia , Filogenia , Prevalência , Doenças dos Roedores/epidemiologia , Trichostomatina/citologia , Trichostomatina/genéticaRESUMO
The taxonomy of Hysterothylacium genus in Mediterranean waters remains incomplete and unresolved. The aim of the current study was to investigate the morphological and molecular identification of selected species of Hysterothylacium larvae in marine fish from the Tunisian Mediterranean coasts. A total of 192 marine fish samples were examined. In total, thirty-seven third-stage larvae of Hysterothylacium were morphologically identified as Hysterothylacium type V. In the present study, representatives of this type from the Mediterranean Sea were genetically characterized for the first time by sequencing the rDNA ITS (ITS1-5.8S-ITS2) regions and mtDNA cox2 gene. This study represents the first report of Hysterothylacium type V from the Mediterranean Sea. We also report Mullus barbatus, M. surmuletus, and Pagellus erythrinus as new hosts for this larval type. Based upon molecular and phylogenetic analyses considering the rDNA ITS regions, the Hysterothylacium type V described here was classified as a new genotype, named Genotype B. The valid genetic data of the described Hysterothylacium type V in the present study can be used to establish the phylogenetic relationships among Hysterothylacium species from the Mediterranean Sea and worldwide for future research.
Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/classificação , Ascaridoidea/crescimento & desenvolvimento , Doenças dos Peixes/parasitologia , Peixes/parasitologia , Animais , Infecções por Ascaridida/parasitologia , Ascaridoidea/anatomia & histologia , Ascaridoidea/genética , DNA Mitocondrial/genética , DNA Espaçador Ribossômico/genética , Peixes/classificação , Genes de Helmintos/genética , Genótipo , Larva/anatomia & histologia , Larva/classificação , Larva/genética , Larva/crescimento & desenvolvimento , Mar Mediterrâneo , FilogeniaRESUMO
Invasive Aedes mosquito species (Diptera: Culicidae) are of public health concern in Europe because they are either recognized or potential vectors of pathogens. Loop-mediated isothermal amplification (LAMP) is a rapid and simple method for amplifying DNA with high specificity and efficiency, with the technique having potential for application in the field, including in high-throughput format. Specific LAMP assays based on rDNA internal transcribed spacers 1 or 2 sequences, considering intraspecies variability at these loci, were developed for Aedes aegypti, Aedes albopictus, Aedes japonicus, Aedes koreicus and the indigenous Aedes geniculatus. No such assays could be developed for Aedes atropalpus and Aedes triseriatus because both loci were too short to serve as target. The assays rely on the clearly visible colour change from violet to sky blue after successful amplification. Sensitivity of egg detection was confirmed with ratios of up to one mosquito egg in 99 other eggs. Simple sample preparation of adults or eggs by mechanical homogenization in water required an additional heat treatment or centrifugation step to avoid non-specific colour changes. Thus, further technical improvements are needed to render these assays truly field-applicable, which would greatly facilitate surveillance of these invasive mosquito species and allow for prompt implementation of control measures.
Assuntos
Aedes/classificação , Mosquitos Vetores/classificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Aedes/genética , Animais , DNA Espaçador Ribossômico/análise , Espécies Introduzidas , Mosquitos Vetores/genéticaRESUMO
Uncaria is a multi-source herb and its species identification has become a bottleneck in quality control. To study the identification method of different Uncaria species herbs through HPLC-MS coupled with rDNA Internal Transcribed Spacer (rDNA ITS) sequence, both plant morphological traits and molecular identification were used to determine the species of every collected Uncaria herb. The genetic analysis of different Uncaria species was performed using their rDNA ITS sequence as a molecular marker. Meanwhile, the phylogenetic relationships of 22 samples from six Uncaria species were divided and classified clearly. By optimizing the chromatographic conditions, a practical HPLC method to differentiate various varieties of Uncaria herbs was set up based on a set of characteristic components across each species. A high-performance liquid chromatography-photodiode array detector tandem ion trap and time of flight mass spectrometry technique combined with reference substances was utilized to derive 21 characteristic compounds containing six groups of six Uncaria species in China. Thus, this study provides a feasible method to solve the current problem of confusion in Uncaria species, and makes a significant step forward in the appropriate clinical use, in-depth research and further utilization of different Uncaria species.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , DNA de Plantas/genética , Espectrometria de Massas por Ionização por Electrospray/métodos , Uncaria , DNA Intergênico/genética , DNA de Plantas/análise , Filogenia , Extratos Vegetais/análise , Extratos Vegetais/química , Folhas de Planta/química , Análise de Sequência de DNA , Uncaria/química , Uncaria/classificação , Uncaria/genéticaRESUMO
Fifty-four single protoplast isolates (SPIs) were regenerated from three Rhizoctonia cerealis strains. A total of 169 rDNA-ITS regions were cloned and sequenced from these 54 SPIs. Variations in the ITS1 and ITS2 regions that flank the 5.8S gene were found within clones from the same strain, as well as within clones from the same SPI. These include variations in GC content and ITS length, and single-nucleotide polymorphisms (SNPs). The different strains and SPIs GC contents range from 40.25 to 41.74% and from 42.40 to 45.02%, in the ITS1 and ITS2 regions, respectively. All SNPs occur in the ITS1 and ITS2 regions, with 3-6 and 4-6 polymorphic sites in each region, respectively, in the different strains. SNP variation is relatively stable within the same strain. For example, the 89 ITS sequences generated from isolate WK-207, regardless of SPI or clone, predominantly cluster into two separate clades on a phylogenetic tree, suggesting that nuclei genetic heterogeneity is related to ITS variation in R. cerealis. Although rDNA-ITS sequences from the three strains and different SPIs are somewhat variable, all of our ITS sequences cluster together in anastomosis subgroup AG-DI during phylogenetic analysis. The ITS variation we observed does not negatively influence R. cerealis anastomosis group or subgroup classification.
Assuntos
DNA Bacteriano/genética , DNA Espaçador Ribossômico/genética , Variação Genética , Rhizoctonia/genética , Evolução Molecular , Filogenia , Rhizoctonia/classificação , Rhizoctonia/isolamento & purificaçãoRESUMO
BACKGROUND: The study presents the phenotypic and genetic characterization of selected P. salmonis isolates from Atlantic salmon and rainbow trout suffering from SRS (salmonid rickettsial septicemia) in Chile and in Canada. The phenotypic characterization of the P. salmonis isolates were based on growth on different agar media (including a newly developed medium), different growth temperatures, antibiotics susceptibility and biochemical tests. RESULTS: This is the first study differentiating Chilean P. salmonis isolates into two separate genetic groups. Genotyping, based on 16S rRNA-ITS and concatenated housekeeping genes grouped the selected isolates into two clades, constituted by the Chilean strains, while the Canadian isolates form a branch in the phylogenetic tree. The latter consisted of two isolates that were different in both genetic and phenotypic characteristics. The phylogenies and the MLST do not reflect the origin of the isolates with respect to host species. The isolates included were heterogeneous in phenotypic tests. CONCLUSIONS: The genotyping methods developed in this study provided a tool for separation of P. salmonis isolates into distinct clades. The SRS outbreaks in Chile are caused by minimum two different genetic groups of P. salmonis. This heterogeneity should be considered in future development of vaccines against this bacterium in Chile. Two different strains of P. salmonis, in regards to genetic and phenotypic characteristics, can occur in the same contemporary outbreak of SRS.
Assuntos
Variação Genética , Filogenia , Piscirickettsia/classificação , Piscirickettsia/fisiologia , Animais , Antibacterianos/farmacologia , Canadá , Chile , Meios de Cultura , Genótipo , Testes de Sensibilidade Microbiana , Oncorhynchus mykiss/microbiologia , Piscirickettsia/efeitos dos fármacos , Piscirickettsia/genética , RNA Ribossômico 16S/genética , TemperaturaRESUMO
Given the widespread distribution and medical implication of members of the genus Hymenolepis, specific identification of the aetiological agent becomes imperative. For precise diagnosis of the species, molecular techniques such as PCR and RFLP of the nuclear ribosomal internal transcribed spacer 2 (rDNA-ITS2) gene marker were carried out. The results showed distinct restriction patterns for both Hymenolepis nana and Hymenolepis diminuta when digested with either of the enzymes RsaI, HaeIII or HhaI. The annotated rDNA-ITS2 sequences from the two species revealed differences in the length; the folded secondary structure also depicted clear demarcation between the two species with variations in length of the helices, pyrimidine-pyrimidine mismatches and sites where motifs occur. In phylogenetic analysis of the evolutionary relationship between the two species as well as with other members of the family Hymenolepididae, the species causing human hymenolepiasis were found to be distantly related as they diverged independently from the ancestral lineage.
Assuntos
DNA Espaçador Ribossômico/genética , Himenolepíase/diagnóstico , Hymenolepis diminuta/genética , Hymenolepis nana/genética , Animais , Diagnóstico Diferencial , Marcadores Genéticos/genética , Humanos , Himenolepíase/parasitologia , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , RatosRESUMO
Leishmaniasis is endemic in southern Europe, and in other European countries cases are diagnosed in travellers who have visited affected areas both within the continent and beyond. Prompt and accurate diagnosis poses a challenge in clinical practice in Europe. Different methods exist for identification of the infecting Leishmania species. Sixteen clinical laboratories in 10 European countries, plus Israel and Turkey, conducted a study to assess their genotyping performance. DNA from 21 promastigote cultures of 13 species was analysed blindly by the routinely used typing method. Five different molecular targets were used, which were analysed with PCR-based methods. Different levels of identification were achieved, and either the Leishmania subgenus, species complex, or actual species were reported. The overall error rate of strains placed in the wrong complex or species was 8.5%. Various reasons for incorrect typing were identified. The study shows there is considerable room for improvement and standardisation of Leishmania typing. The use of well validated standard operating procedures is recommended, covering testing, interpretation, and reporting guidelines. Application of the internal transcribed spacer 1 of the rDNA array should be restricted to Old World samples, while the heat-shock protein 70 gene and the mini-exon can be applied globally.
Assuntos
Proteínas de Choque Térmico HSP70/genética , Leishmania/genética , Leishmaniose/diagnóstico , Reação em Cadeia da Polimerase/métodos , DNA de Cinetoplasto , DNA de Protozoário/genética , DNA Ribossômico , Europa (Continente) , Genótipo , Humanos , Israel , Laboratórios , Leishmania/isolamento & purificação , Polimorfismo de Fragmento de Restrição , Sensibilidade e Especificidade , TurquiaRESUMO
As an insufficiently utilized energy resource, oil shale is conducive to the formation of characteristic microbial communities due to its special geological origins. However, little is known about fungal diversity in oil shale. Polymerase chain reaction cloning was used to construct the fungal ribosomal deoxyribonucleic acid internal transcribed spacer (rDNA ITS) clone libraries of Huadian Mine in Jilin Province, Maoming Mine in Guangdong Province, and Fushun Mine in Liaoning Province. Pure culture and molecular identification were applied for the isolation of cultivable fungi in fresh oil shale of each mine. Results of clone libraries indicated that each mine had over 50% Ascomycota (58.4%-98.9%) and 1.1%-13.5% unidentified fungi. Fushun Mine and Huadian Mine had 5.9% and 28.1% Basidiomycota, respectively. Huadian Mine showed the highest fungal diversity, followed by Fushun Mine and Maoming Mine. Jaccard indexes showed that the similarities between any two of three fungal communities at the genus level were very low, indicating that fungi in each mine developed independently during the long geological adaptation and formed a community composition fitting the environment. In the fresh oil-shale samples of the three mines, cultivable fungal phyla were consistent with the results of clone libraries. Fifteen genera and several unidentified fungi were identified as Ascomycota and Basidiomycota using pure culture. Penicillium was the only genus found in all three mines. These findings contributed to gaining a clear understanding of current fungal resources in major oil-shale mines in China and provided useful information for relevant studies on isolation of indigenous fungi carrying functional genes from oil shale.
Assuntos
Biodiversidade , Fungos/classificação , Campos de Petróleo e Gás/microbiologia , China , DNA Fúngico/genética , Fungos/genética , Mineração , Filogenia , Análise de Sequência de DNARESUMO
A general phylogeny of Pluteus section Celluloderma based on nuc rITS1-5.8-ITS2 (ITS) barcode sequences is presented with description of eight new species from Brazil supported by morphological and molecular data: P. brunneocrinitus, P. cebolinhae, P. crinitus, P. halonatus, P. hispidulopsis, P. karstedtiae, P. necopinatus and P. paucicystidiatus.
Assuntos
Agaricales/classificação , Agaricales/isolamento & purificação , Agaricales/genética , Agaricales/crescimento & desenvolvimento , Brasil , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Dados de Sequência Molecular , Técnicas de Tipagem Micológica , Filogenia , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificaçãoRESUMO
Cyanophora is an important glaucophyte genus of unicellular biflagellates that may have retained ancestral features of photosynthetic eukaryotes. The nuclear genome of Cyanophora was recently sequenced, but taxonomic studies of more than two strains are lacking for this genus. Furthermore, no study has used molecular methods to taxonomically delineate Cyanophora species. Here, we delimited the species of Cyanophora using light and electron microscopy, combined with molecular data from several globally distributed strains, including one newly established. Using a light microscope, we identified two distinct morphological groups: one with ovoid to ellipsoidal vegetative cells and another with dorsoventrally flattened or broad, bean-shaped vegetative cells containing duplicated plastids. Our light and scanning electron microscopy clearly distinguished three species with ovoid to ellipsoidal cells (C. paradoxa Korshikov, C. cuspidata Tos.Takah. & Nozaki sp. nov., and C. kugrensii Tos.Takah. & Nozaki sp. nov.) and two species with broad, bean-shaped cells (C. biloba Kugrens, B.L.Clay, C.J.Mey. & R.E.Lee and C. sudae Tos.Takah. & Nozaki sp. nov.) based on differences in cell shape and surface ornamentations of the vegetative cells under the field-emission scanning electron microscope. Molecular phylogenetic analyses of P700 chl a apoprotein A2 (psaB) genes and internal transcribed spacer (ITS) regions of nuclear ribosomal DNA (rDNA), as well as a comparison of secondary structures of nuclear rDNA ITS-2 and genetic distances of psaB genes, supported the delineation of five morphological species of Cyanophora.
RESUMO
As major contributors of the ripening process, yeasts and filamentous fungi play a fundamental role in cheese-making. Still, there is no rapid and affordable identification method available for both yeasts and filamentous fungi encountered in cheeses. In the present study, we developed a method based on CE-SSCP analysis of nuclear ribosomal DNA ITS amplicons, along with a species pattern database comprising 37 fungal species. By combining analyses of the ITS1 and ITS2 conformers, 25 out of 37 species were discriminated using CE-SSCP analysis. This reproducible and sensitive method was applied to determine the fungal community composition of 36 cheeses including blue-veined, pressed-cooked, pressed-uncooked, red-smear and surface-mould ripened cheeses. Overall, each cheese contained between 1 and 6 fungal species and 23 different species of fungi were detected including 8 yeast species, 9 filamentous species and 6 unidentified species. Comparison of the fungal diversity obtained after cloning and sequencing (rDNA ITS) versus CE-SSCP for 8 cheeses showed that CE-SSCP was at least as exhaustive as cloning and sequencing of thirty clones per cheese. In conclusion, this CE-SSCP method was an effective tool to identify the fungi present in various cheese varieties and may be of interest for the cheese industry to rapidly describe the composition of cheese fungal communities.
Assuntos
Queijo/microbiologia , Eletroforese Capilar/métodos , Fungos/genética , Fungos/isolamento & purificação , Técnicas de Tipagem Micológica/métodos , Polimorfismo Conformacional de Fita Simples , Fungos/classificação , Dados de Sequência Molecular , FilogeniaRESUMO
An endophytic fungus isolated from Camellia sinensis, Assam, Northeastern India was identified as Colletotrichum gloeosporioides on the basis of morphological characteristics and rDNA ITS analysis. This endophytic fungus was evaluated for growth inhibition against tea pathogens Pestalotiopsis theae and Colletotrichum camelliae. One isolate of C. gloeosporioides showed strong antagonistic activity against Pestalotiopsis theae (64 %) and moderate activity against C. camelliae (37 %). Fifty percent cell-free culture filtrate from 5-day-old cultures showed highest antagonistic activity against both the pathogens although the inhibition percent was less as compared to dual culture. In the experiment of volatile compounds none of the isolates of C. gloeosporioides strains showed visible inhibition against P. theae and C. camelliae. The activity of extracellular hydrolytic enzymes chitinase and protease was also high in this culture fluid and measured 10 and 4.3 IU/µl, respectively.
RESUMO
Comprehending the phylogeography of invasive organisms enhances our insight into their distribution dynamics, which is instrumental for the development of effective prevention and management strategies. In China, Pomacea canaliculata and Pomacea maculata are the two most widespread and damaging species of the non-native Pomacea spp.. Given this species' rapid spread throughout country, it is urgent to investigate the genetic diversity and structure of its different geographic populations, a task undertaken in the current study using the COI and ITS1 mitochondrial and ribosomal DNA genes, respectively. The result of this study, based on a nationwide systematic survey, a collection of Pomacea spp., and the identification of cryptic species, showed that there is a degree of genetic diversity and differentiation in P. canaliculata, and that all of its variations are mainly due to differences between individuals within different geographical populations. Indeed, this species contains multiple haplotypes, but none of them form a systematic geographical population structure. Furthermore, the COI gene exhibits higher genetic diversity than the ITS1 gene. Our study further clarifies the invasive pathways and dispersal patterns of P. canaliculata in China to provide a theoretical basis.
Assuntos
Complexo IV da Cadeia de Transporte de Elétrons , Variação Genética , Genética Populacional , Haplótipos , China , Animais , Complexo IV da Cadeia de Transporte de Elétrons/genética , Filogeografia , Filogenia , Espécies Introduzidas , DNA Espaçador Ribossômico/genética , Gastrópodes/genéticaRESUMO
Fascioliasis is a snail-borne zoonotic disease with impact on the development of human subjects and communities. It is caused by two liver-infecting fasciolid trematode species, the globally-distributed Fasciola hepatica and the Africa/Asia-restricted but more pathogenic, larger F. gigantica. Fasciola gigantica is the cause of endemicity in livestock throughout the warm lowlands from Pakistan to southeastern Asia since old times. Human fascioliasis is emerging in this region at present, with an increase of patient reports. Complete sequences of rDNA ITS-1 and ITS-2 spacers and mtDNA nad1 and cox1 genes were obtained from fasciolid eggs found in the endoscopic bile aspirate from a patient of Arunachal Pradesh, northeastern India. Egg measurements, pronounced ITS heterozygosity, and pure F. gigantica mtDNA haplotypes demonstrate an infection by a recent F. gigantica-like hybrid. Sequence identities and similarities with the same DNA markers found in livestock from Bangladesh prove the human-infecting fasciolid to present identical ITSs and nad1 haplotypes and only one silent transversion in cox1 when compared to a widely-spread combined haplotype in animals. In northeastern India and Bangladesh, human fascioliasis emergence appears linked to increasing livestock prevalences due to: ruminant importation from other countries because of the increasing demand of rapidly growing human populations; numerous livestock movements, including transborder corridors, due to the uncontrolled small-scale household farming practices; and man-made introduction of F. hepatica with imported livestock into an area originally endemic for F. gigantica leading to frequent hybridization. Sequences, phylogenetic trees, and networks indicate that the origins of intermediate/hybrid fasciolids and factors underlying human infection risk differ in eastern and western South Asia. The emergence scenario in southern China and Vietnam resembles the aforementioned of northeastern India and Bangladesh, whereas in Pakistan it is linked to increasing monsoon rainfall within climate change combined with an impact of an extensive irrigation system. Past human-guided movements of pack animals along the western Grand Trunk Road and the eastern Tea-Horse Road explain the F. gigantica mtDNA results obtained. Physicians should be aware about these emerging scenarios, clinical pictures, diagnostic techniques and treatment. Government authorities must appropriately warn health professionals, ensure drug availability and improve livestock control.