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81 result(s) for "ITS2 region"
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Into the Plastisphere, Where Only the Generalists Thrive: Early Insights in Plastisphere Microbial Community Succession
The ubiquity of plastic debris in marine environments raises the question, what impacts do plastics have on our marine microbiota? To investigate this, we applied bacterial 16S rRNA gene and fungal ITS2 region sequencing to identify changes in microbial biofilm community compositions on marine plastic, over time. We sampled biofilm on virgin linear low-density polyethylene (LLDPE), nylon-6 (PA) and glass after 2, 6 and 12 weeks of constant immersion in Te Whakaraupō-Lyttelton Harbour, Aotearoa-New Zealand. Of the prokaryotes, Proteobacteria and Bacteroidetes were predominant in all samples and Verrucomicrobiota were most abundant in mature biofilms. Microbial communities on the three substrate types were significantly distinct from those in the surrounding seawater, regardless of age, but not between attachment substrates. Bacterial communities occurring two weeks after immersion and fungal communities at six weeks were found to vary more among substrate types than at other times; however, no significant substrate-specific communities were identified overall. Taxa closely related to previously reported plastic-biodegrading species were found in very low abundance across all substrates, including on the glass slides. Our findings suggest that microorganisms do not selectively persist on the LLDPE or PA surfaces to gain significant direct metabolic benefit, instead using these plastics primarily as an attachment surface on which they form generalist biofilm communities.
Evidence of the presence of Borrelia burgdorferi in dogs and associated ticks in Egypt
Background Borrelia burgdorferi is the spirochete that causes Lyme Borreliosis (LB), which is a zoonotic tick-borne disease of humans and domestic animals. Hard ticks are obligate haematophagous ectoparasites that serve as vectors of Borrelia burgdorferi . Studies on the presence of Lyme borreliosis in Egyptian animals and associated ticks are scarce. Methods This study was conducted to detect B. burgdorferi in different tick vectors and animal hosts. Three hundred animals (dogs=100, cattle=100, and camels=100) were inspected for tick infestation. Blood samples from 160 tick-infested animals and their associated ticks ( n =1025) were collected and examined for the infection with B. burgdorferi by polymerase chain reaction (PCR) and sequencing of the 16S rRNA gene. The identified tick species were characterized molecularly by PCR and sequencing of the ITS2 region. Results The overall tick infestation rate among examined animals was 78.33% (235/300). The rate of infestation was significantly higher in camels (90%), followed by cattle (76%) and dogs (69%); ( P = 0.001). Rhipicephalus sanguineus , Rhipicephalus (Boophilus) annulatus , and both Hyalomma dromedarii and Amblyomma variegatum, were morphologically identified from infested dogs, cattle, and camels; respectively. Molecular characterization of ticks using the ITS2 region confirmed the morphological identification, as well as displayed high similarities of R. sanguineus, H. dromedarii, and A. Variegatu with ticks identified in Egypt and various continents worldwide. Just one dog (1.67%) and its associated tick pool of R. sanguineus were positive for B. burgdorferi infection. The 16S rRNA gene sequence for B. burgdorferi in dog and R. sanguineus tick pool showed a 100% homology. Conclusion Analyzed data revealed a relatively low rate of B. burgdorferi infection, but a significantly high prevalence of tick infestation among domesticated animals in Egypt, which possesses a potential animal and public health risk. Additionally, molecular characterization of ticks using the ITS2 region was a reliable tool to discriminate species of ticks and confirmed the morphological identification.
Comparative Analysis of Grapevine Epiphytic Microbiomes among Different Varieties, Tissues, and Developmental Stages in the Same Terroir
There is limited knowledge about the relationships of epiphytic microbiomes associated with the phyllosphere of different Vitis vinifera cultivars in the same vineyard and terroir. To address this research gap, we investigated the microbiome compositionof 36 grapevine genotypes grown in the same vineyard in different plant sections during the growing season. Using high-throughput NGS-based metagenomic analysis targeting the ITS2 and the V4 regions of the 16S ribosomal gene of fungal and bacterial communities, respectively, weassessed the impact of grapevine genotypes on microbial assemblages in various parts of the phyllosphere. The results indicated that different phyllosphere tissues display high microbial diversity regardless of the cultivars’ identity and use. The selected three phyllosphere parts representing three distinct phenological stages, namely bark and bud, berry set, and fruit harvest, had almost a similar number of fungal OTUs, while a difference was recorded for the bacterial species. The fruit harvest stage hosted the highest number of bacterial OTUs, whereas the bark and bud stage contained the lower. Bacterial dominant phyla were Proteobacteria, Bacteroidetes, Actinobacteria, and Firmicutes, and the genera were Gluconacetobacter, Erwinia, Gluconobacter, Zymobacter, Buchnera, Pseudomonas, Pantoea, Hymenobacter, Pedobacter, Frigoribacterium, Sphingomonas, and Massilia. For fungi, the dominant phyla were Ascomycota and Basidiomycota, and the genera were Aureobasidium, Cladosporium, Alternaria, Aspergillus, Davidiella, Phoma, Epicoccum, Rhodosporidium, Glomerella, Botryosphaeria, Metschnikowia, Issatchenkia, and Lewia. Both the genotype of the cultivar and the phenological stage appeared to considerably impact the shape of microbial diversity and structure within the same terroir. Taken together, these results indicate that microbiome analysis could be proved to be an important molecular fingerprint of cultivars and provide an efficient management tool for the traceability of wine and grape end products. Moreover, the unique identity of cultivars’ microbial signatures highlights the need for further development of precision management to support viticulture sustainability in the face of climate change.
q-PCR-based assay for the toxic dinoflagellate Karenia selliformis monitoring along the Tunisian coasts
Karenia selliformis is a marine dinoflagellate responsible for fish-kill events. Its presence has been reported along the Tunisian coasts (south-eastern Mediterranean Sea) since the 1990s. In the present study, a quantitative-PCR assay, based on the internal transcribed spacer (ITS) molecular marker, was developed to detect and quantify K. selliformis in environmental bivalve mollusk samples and in seawater samples. The assay was optimized, and its specificity was confirmed using cross-reactivity experiments against microalgal species commonly found on the Tunisian coasts and/or closely related to K. selliformis . Calibration curves were performed by tenfold dilutions of plasmid DNA harboring target sequence and genomic DNA, attaining a limit of detection of around 5 copies of target DNA per reaction, far below one K. selliformis cell per reaction. The field application of the developed assay showed a powerful detection capability. Thus, the designed assay could contribute to the deployment of in-field diagnostic tools for K. selliformis blooms monitoring.
Quantitative PCR assay for the simultaneous identification and enumeration of multiple Karenia species
Quantitative PCR (qPCR) is the method of choice for specific detection and quantification of harmful algal bloom (HAB) species. Development of qPCR assay for simultaneous enumeration of species that frequently co-exist in HABs is required. A high sensitivity TaqMan qPCR assay, using probe and primers, located at ITS1–5.8S–ITS2 rDNA region, detecting, specifically, Karenia selliformis , K. bidigitata , and K. mikimotoi , was designed. ITS1–5.8S–ITS2 rDNA region copy numbers per Karenia cell genome were estimated to 217.697 ± 67.904, allowing cell quantification. An application of the designed methodology in field samples has been conducted, and it showed high sensitivity (detection of around 10 −1 cell/100 mg of bivalve mollusk tissue, equivalent to about 20 copies of the target sequence). We suggest that the optimized method could contribute to early detection of three closely related Karenia species in seafood cultivating areas to promote control quality, guarantee a fast and effective intervention, and improve public health prevention.
Diagnostic comparison of Baermann funnel, Koga agar plate culture and polymerase chain reaction for detection of human Strongyloides stercoralis infection in Maluku, Indonesia
Human infection with the nematode Strongyloides stercoralis, which may have a life-threatening course, primarily occurs in tropical settings. Epidemiological data on the occurrence of strongyloidiasis are scarce, and microscopic stool-based detection methods are insensitive. Polymerase chain reaction (PCR) assays have been developed, yet conflicting results have been reported. Our goal was to determine whether there was diagnostic agreement between an in-house PCR and two microscopic techniques, the Baermann funnel (BM) and the Koga agar plate culture (KAP) for the detection of S. stercoralis in stool samples. Eighty ethanol-fixed stool samples stemming from a cross-sectional survey in Maluku, Indonesia, were purposefully selected for PCR analysis. The final sample size comprised four groups, each with 20 samples: group 1, positive for S. stercoralis on both BM and KAP; group 2, positive only by BM; group 3, positive only by KAP; and group 4, negative on both BM and KAP. A Strongyloides-specific PCR targeting the internal transcribed spacer 2 (ITS2) region was carried out in an Indonesian reference laboratory. The overall agreement between PCR and microscopy was 61% (49/80 samples), being highest in group 1 (15/20, 75%) and lowest in group 3 (9/20, 45%). PCR revealed eight additional S. stercoralis infections in group 4. Future studies should elucidate the ‘true’ infection status of samples that are negative by PCR, but positive upon microscopy. Taken together, there is a lack of agreement between microscopy and PCR results for the diagnosis of human S. stercoralis infection in Indonesia. ClinicalTrials.gov (identifier: NCT02105714)
Development of a novel TaqMan qPCR assay for rapid detection and quantification of Gymnodinium catenatum for application to harmful algal bloom monitoring in coastal areas of Tunisia
Gymnodinium catenatum is a dinoflagellate known to cause paralytic shellfish poisoning (PSP), commonly associated with human muscular paralysis, neurological symptoms, and, in extreme cases, death. In the present work, we developed a real-time PCR-based assay for the rapid detection of the toxic microalgal species, G. catenatum , in environmental bivalve mollusc samples as well as seawater samples. G. catenatum -specific primers and probe were designed on the ITS1-5.8S-ITS2 rDNA region. Hydrolysis probe qPCR assay was optimized. ITS1-5.8S-ITS2 rDNA region copy numbers per G. catenatum cell genome were estimated to be 122.73 ± 5.54 copies/cell, allowing cell quantification. The application of the optimized qPCR assay for G. catenatum detection and quantification in field samples has been conducted, revealing high sensitivity (detection of around 1.310 5 cells/L of seawater samples. Thus, the designed hydrolysis probe qPCR assay could be considered an efficient tool for phytoplankton monitoring whilst ensuring accuracy and sensitivity and providing cost and time savings.
Developmental stages of Notocotylus magniovatus Yamaguti, 1934, Catatropis vietnamensis n. sp., Pseudocatatropis dvoryadkini n. sp., and phylogenetic relationships of Notocotylidae Lühe, 1909
Data on the life cycles and morphology of the developmental stages of Notocotylus magniovatus, Catatropis vietnamensis n. sp., and Pseudocatatropis dvoryadkini n. sp. were obtained. The Pseudocatatropis genus was restored based on our results. For the studied trematodes, the snails Parajuga spp., Helicorbis sujfunensis (Russia), and Melanoides tuberculata (Vietnam) serve as first intermediate hosts. It has been established that C. vietnamensis n. sp. differs from Catatropis harwoodi and Catatropis pakistanensis in the length of the ridge and metraterm and the location of the anterior papillae. In the life cycle of P. dvoryadkini n. sp., as in Pseudocatatropis joyeuxi, cercariae do not leave the first intermediate host. Both species are very similar in morphometric features, despite the fact that they share no common first intermediate hosts in their life cycles, and the areas of the European and Asian populations of flukes do not overlap. In phylogenetic trees and genetic distances based on the nucleotide sequences of the 28S gene and the ITS2 region of ribosomal DNA, Notocotylus attenuatus, Notocotylus intestinalis, and Notocotylus magniovatus are combined into one systematic group, while C. vietnamensis n. sp. and Catatropis indicus form another group. A third group includes members of different genera: P. dvoryadkini n. sp., and Notocotylus malhamensis, as well as three unclassified Notocotylus spp. The presence in the last group of flukes with three rows of papillae and a median ridge and lateral papillae indicates that these systematic criteria are not determinant in establishing membership of the parasitic worms to one or another genus of Notocotylidae.
Biosystematic Study on Some Egyptian Species of Astragalus L. (Fabaceae)
Astragalus L. is one of the largest angiosperm complex genera that belongs to the family Fabaceae, subfamily Papilionoideae or Faboideae under the subtribe Astragalinae of the tribe Galegeae. The current study includes the whole plant morphology, DNA barcode (ITS2), and molecular marker (SCoT). Ten taxa representing four species of Astragalus were collected from different localities in Egypt during the period from February 2018 to May 2019. Morphologically, identification and classification of collected Astragalus plants occurred by utilizing the light microscope, regarding the taxonomic revisions of the reference collected Astragalus specimens in other Egyptian Herbaria. For molecular validation, ten SCoT primers were used in this study, producing a unique banding pattern to differentiate between ten samples of Astragalus taxa which generated 212 DNA fragments with an average of 12.2 bands per 10 Astragalus samples, with 8 to 37 fragments per primer. The 212 fragments amplified were distributed as 2 monomorphic bands, 27 polymorphic without unique bands, 183 unique bands (210 Polymorphic with unique bands), and ITS2 gene sequence was showed as the optimal barcode for identifying Astragalus L. using BLAST searched on NCBI database, and afterward, analyzing the chromatogram for ITS region, 10 samples have been identified as two samples representing A. hauarensis, four samples representing A. sieberi, three samples representing A. spinosus and one sample representing A. vogelii. Based on the ITS barcode, A. hauarensis RMG1, A. hauarensis RMG2, A. sieberi RMG1, A. sieberi RMG2, A. sieberi RMG3, A. sieberi RMG4, A. spinosus RMG1, A. spinosus RMG2, A. spinosus RMG3, A. vogelii RMG were deposited into GenBank with accession # MT367587.1, MT367591.1, MT367593.1, MT367585.1, MT367586.1, MT367588.1, MT160347.1, MT367590.1, MT367589.1, MT367592.1, respectively. These results indicated the efficiency of SCoT markers and ITS2 region in identifying and determining genetic relationships between Astragalus species.
Monogeneans on exotic Indian freshwater fish. 7. Results of a national study on ornamental fishes from 2019–2022
This study reports the results of a nationwide parasitological survey that was conducted from 2019 to 2022 to investigate the potential introduction of monogenean parasites into India via the ornamental fish trade. A total of 619 individual exotic ornamental fish representing 27 teleost species from nine families were collected from the country’s major aquaria markets and examined for monogeneans. To identify monogeneans at the species level, we employed a morphometric analysis of sclerotised structures (haptoral and reproductive hard parts), as well as a molecular analysis of nuclear 28S rRNA and ITS2 regions. Indian conditions for importing exotic ornamental fish species require a pre-quarantine certificate, quarantine treatment, and post-quarantine follow-up. Despite these restrictions, 26 monogenean species from 12 known genera were detected and identified in 17 of the 27 fishes examined. Dactylogyrus was represented by a maximum of nine species, followed by Gyrodactylus with five. Cyprinidae was the most parasitised fish family (13 species), followed by Cichlidae (three species) and Helostomatidae, Poeciliidae, and Serrasalmidae (two species each). The majority of co-transported parasite species originated from Asia (65.38%, n  = 17), followed by South America (23.07%, n  = 6), North and Central America (7.69%, n  = 2), and Africa (3.5%, n  = 1). Three fish species were identified as the first host records for monogenean parasites: Chindongo socolofi for Cichlidogyrus tilapiae Paperna, 1960, Metynnis hypsauchen for Mymarothecium sp., and Betta splendens for Heteronchocleidus sp. In general, exotic populations had fewer parasite species than in their native distribution ranges. Cette étude présente les résultats d’une enquête parasitologique nationale menée de 2019 à 2022 afin d’étudier l’introduction potentielle de monogènes parasites en Inde via le commerce de poissons d’ornement. Au total, 619 poissons d’ornement exotiques, représentant 27 espèces de téléostéens appartenant à neuf familles, ont été collectés sur les principaux marchés aquariophiles du pays et examinés à la recherche de Monogènes. Pour identifier les Monogènes à l’échelle de l’espèce, nous avons utilisé une analyse morphométrique des structures sclérifiées (parties dures du hapteur et de l’appareil reproducteur), ainsi qu’une analyse moléculaire des régions nucléaires de l’ARNr 28S et de l’ITS2. En Inde, les conditions d’importation des espèces de poissons d’ornement exotiques exigent un certificat de pré-quarantaine, un traitement de quarantaine et un suivi post-quarantaine. Malgré ces restrictions, 26 espèces de 12 genres connus de Monogènes ont été détectées et identifiées chez 17 des 27 poissons examinés. Dactylogyrus était représenté par un maximum de neuf espèces, suivi de Gyrodactylus avec cinq. Les Cyprinidae était la famille de poissons la plus parasitée (13 espèces), suivie des Cichlidae (trois espèces) et des Helostomatidae, Poeciliidae et Serrasalmidae (deux espèces chacune). La majorité des espèces de parasites co-transportés provenaient d’Asie (65,38 %, n  = 17), suivie par l’Amérique du Sud (23,07 %, n  = 6), l’Amérique du Nord et l’Amérique centrale (7,69 %, n  = 2) et l’Afrique (3,5 %, n  = 1). Trois espèces de poissons ont été identifiées comme premiers hôtes signalés pour des Monogènes : Chindongo socolofi pour Cichlidogyrus tilapiae Paperna, 1960, Metynnis hypsauchen pour Mymarothecium sp. et Betta splendens pour Heteronchocleidus sp. En général, les populations exotiques comptaient moins d’espèces de parasites que dans leurs aires de répartition d’origine.