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1.
EMBO Rep ; 24(12): e57984, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37921038

RESUMO

The rixosome defined in Schizosaccharomyces pombe and humans performs diverse roles in pre-ribosomal RNA processing and gene silencing. Here, we isolate and describe the conserved rixosome from Chaetomium thermophilum, which consists of two sub-modules, the sphere-like Rix1-Ipi3-Ipi1 and the butterfly-like Las1-Grc3 complex, connected by a flexible linker. The Rix1 complex of the rixosome utilizes Sda1 as landing platform on nucleoplasmic pre-60S particles to wedge between the 5S rRNA tip and L1-stalk, thereby facilitating the 180° rotation of the immature 5S RNP towards its mature conformation. Upon rixosome positioning, the other sub-module with Las1 endonuclease and Grc3 polynucleotide-kinase can reach a strategic position at the pre-60S foot to cleave and 5' phosphorylate the nearby ITS2 pre-rRNA. Finally, inward movement of the L1 stalk permits the flexible Nop53 N-terminus with its AIM motif to become positioned at the base of the L1-stalk to facilitate Mtr4 helicase-exosome participation for completing ITS2 removal. Thus, the rixosome structure elucidates the coordination of two central ribosome biogenesis events, but its role in gene silencing may adapt similar strategies.


Assuntos
Proteínas de Saccharomyces cerevisiae , Schizosaccharomyces , Humanos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas Nucleares/metabolismo , Rotação , RNA Ribossômico/metabolismo , Ribossomos/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Processamento Pós-Transcricional do RNA , Proteínas Ribossômicas/genética
2.
BMC Bioinformatics ; 25(1): 228, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956506

RESUMO

BACKGROUND: Fungi play a key role in several important ecological functions, ranging from organic matter decomposition to symbiotic associations with plants. Moreover, fungi naturally inhabit the human body and can be beneficial when administered as probiotics. In mycology, the internal transcribed spacer (ITS) region was adopted as the universal marker for classifying fungi. Hence, an accurate and robust method for ITS classification is not only desired for the purpose of better diversity estimation, but it can also help us gain a deeper insight into the dynamics of environmental communities and ultimately comprehend whether the abundance of certain species correlate with health and disease. Although many methods have been proposed for taxonomic classification, to the best of our knowledge, none of them fully explore the taxonomic tree hierarchy when building their models. This in turn, leads to lower generalization power and higher risk of committing classification errors. RESULTS: Here we introduce HiTaC, a robust hierarchical machine learning model for accurate ITS classification, which requires a small amount of data for training and can handle imbalanced datasets. HiTaC was thoroughly evaluated with the established TAXXI benchmark and could correctly classify fungal ITS sequences of varying lengths and a range of identity differences between the training and test data. HiTaC outperforms state-of-the-art methods when trained over noisy data, consistently achieving higher F1-score and sensitivity across different taxonomic ranks, improving sensitivity by 6.9 percentage points over top methods in the most noisy dataset available on TAXXI. CONCLUSIONS: HiTaC is publicly available at the Python package index, BIOCONDA and Docker Hub. It is released under the new BSD license, allowing free use in academia and industry. Source code and documentation, which includes installation and usage instructions, are available at https://gitlab.com/dacs-hpi/hitac .


Assuntos
Fungos , Aprendizado de Máquina , Fungos/genética , Fungos/classificação , DNA Espaçador Ribossômico/genética , Software
3.
BMC Genomics ; 25(1): 130, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302916

RESUMO

BACKGROUND: Circadian rhythm is crucial to the function of the immune system. Disorders of the circadian rhythm can contribute to inflammatory diseases such as Ulcerative colitis (UC). This Mendelian Randomization (MR) analysis applies genetic tools to represent the aggregated statistical results of exposure to circadian rhythm disorders and UC and its comorbidities, allowing for causal inferences. METHODS: Summary statistics of protein, DNA methylation and gene expression quantitative trait loci in individuals of European ancestry (pQTL, mQTL, and eQTL, respectively) were used. Genetic variants located within or near 152 circadian clock-related genes and closely related to circadian rhythm disorders were selected as instrumental variables. Causal relationships with UC and its comorbidities were then estimated through employed Summary data-based Mendelian Randomization (SMR) and Inverse-Variance-Weighted MR (IVW-MR). RESULTS: Through preliminary SMR analysis, we identified a potential causal relationship between circadian clock-related genes and UC along with its comorbidities, which was further confirmed by IVW-MR analysis. Our study identified strong evidence of positive correlation involving seven overlapping genes (CSNK1E, OPRL1, PIWIL2, RORC, MAX, PPP5C, and AANAT) through MWAS and TWAS in UC, four overlapping genes (OPRL1, CHRNB2, FBXL17, and SIRT1) in UC with PSC, and three overlapping genes (ARNTL, USP7, and KRAS) in UC with arthropathy. CONCLUSIONS: This SMR study demonstrates the causal effect of circadian rhythm disorders in UC and its comorbidities. Furthermore, our investigation pinpointed candidate genes that could potentially serve as drug targets.


Assuntos
Transtornos Cronobiológicos , Relógios Circadianos , Colite Ulcerativa , Humanos , Colite Ulcerativa/genética , Relógios Circadianos/genética , Análise da Randomização Mendeliana , Comorbidade , Estudo de Associação Genômica Ampla , Peptidase 7 Específica de Ubiquitina , Proteínas Argonautas
4.
Funct Integr Genomics ; 24(2): 64, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517551

RESUMO

Pittosporum (Pittosporaceae) is famous as the ornamental and medical values, which is distributed tropical and subtropical regions of Eastern Hemisphere. The few phylogenetic studies have included samples from the Pacific Island, but the phylogenetic relationships of Asian species has not been studied. Here, the complete chloroplast (cp) genomes of ten Pittosporum species from East Asia were first sequenced and compared with those of the published species of this genus. Our results indicated that cp genomes of these species had a typical and conserved quadripartite structure. 131 genes were identical in order and orientation and no changes of inverted repeat (IR) occurred. However, the comparative analysis of cp genomes suggested that sequence divergence mainly appeared in non-coding or intergenic regions, in which several divergence hotspots were identified. By contrast, protein-coding genes showed the lowest variance under strong purifying selection. Phylogenetic analysis based on the cp genome sequences showed that the tested Pittosporum species were clustered into two major clades, in which the Asian species formed Clade I and the remaining species from Australia and New Zealand formed Clade II with high support values, which was consistent with the results of ITS data with low support values. These results suggested that cp genome is a robust phylogenetic indicator for deep nodes in the phylogeny of Pittosporum. Meanwhile, these results will provide the valuable information to better understand the phylogeny and biogeography of Pittosporum.


Assuntos
Genoma de Cloroplastos , Filogenia , Ásia Oriental
5.
BMC Plant Biol ; 24(1): 103, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38331718

RESUMO

BACKGROUND: The establishment of mycorrhizal relationships between a fungus and a plant typically enhances nutrient and water uptake for the latter while securing a carbon source for the fungus. However, under a particular set of environmental conditions, such as low availability of light and abundant nutrients in the soil, the resources invested in the maintenance of the fungi surpass the benefits obtained by the host. In those cases, facultative mycorrhizal plants are capable of surviving without symbiosis. Facultative mycorrhization in ferns has been overlooked until now. The present study measured the response of Struthiopteris spicant L. Weiss, and its root-associated fungi to different levels of light and nutrient availability in terms of growth, mycorrhizal presence, and leaf nutrient content. This fern species exhibits a great tolerance to variable light, nutrient, and pH conditions, and it has been found with and without mycorrhizae. We conducted a greenhouse experiment with 80 specimens of S. spicant and three factors (Light, Phosphorus, and Nitrogen) resulting in eight treatments. RESULTS: We found a significant influence of the factor light on fungal community composition, plant biomass, and nutrient accumulation. Departing from a lack of colonization at the initial stage, plants showed a remarkable increment of more than 80% in the arbuscular mycorrhizal fungi (AMF) richness and abundance in their roots when grown under high light conditions, compared with the ones in low light. We also observed an upward trend of C:P and C:N ratios and the above- and belowground biomass production when AMF abundance increased. Furthermore, the compositional analysis of the whole fungal communities associated with S. spicant roots revealed clear differences among low-light and high-light treatments. CONCLUSIONS: This study is the first to investigate the importance of light and nutrient availability in determining fern-AMF relationships. We confirmed that Struthiopteris spicant is a facultative mycorrhizal plant. The composition and diversity of AMF found in the roots of this fern are strongly influenced by light and less by nutrient conditions. Our study shows that ferns respond very sensitively to changes in environmental factors, leading to shifts in the associated mycorrhizal communities.


Assuntos
Gleiquênias , Micorrizas , Raízes de Plantas , Micorrizas/fisiologia , Simbiose , Solo/química , Microbiologia do Solo
6.
Appl Environ Microbiol ; 90(8): e0085724, 2024 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-39082859

RESUMO

Fungi compose a minority but a common component of normal oral microbiota and contribute to oral and systemic health by interacting with bacterial inhabitants. This study investigated the relationship of oral fungal profiles to health status and bacterial profiles of 159 elderly adults receiving community support and home care services. Fungal and bacterial densities and compositions were determined based on the fungal ribosomal internal transcribed spacer region and bacterial 16S rRNA gene amplicon analyses, respectively. The total fungal density of 87 individuals exceeded 5,000 copies, and their microbiota was characterized by significantly less dense bacterial populations and lower relative abundances of oral health-associated taxa, such as Neisseria perflava and Porphyromonas pasteri, compared with those with less than 5,000 copies of fungi. These individuals were significantly older, had fewer teeth, had lower physical function, and comprised more denture users and individuals with cognitive decline. Fungal compositions were classified into three profiles (Candida albicans-dominant, non-albicans Candida-dominant, and non-Candida-dominant), and individuals with a non-albicans Candida-dominant profile exhibited significantly lower physical and cognitive function than those with the Candida albicans-dominant profile. These results demonstrate that a high-density fungal population co-occurs with poor oral and systemic health status of the host and dysbiosis of the bacterial community, and particularly, the overgrowth of non-albicans Candida species may be implicated in worsening systemic conditions. IMPORTANCE: The interaction between fungal and bacterial components involved in the virulence of oral microbiota has received attention. This study demonstrates that an increase in fungal components is associated with a dysbiotic bacterial community and poor health status in elderly adults. Among individuals with a high-density fungal population, particularly, those with a non-albicans Candida-dominant profile had lower physical and cognitive functions than those with a C. albicans-dominant profile. These findings indicate that the evaluation of fungal components, in addition to the bacterial components, is important to understand the involvement of oral microbiota in oral and systemic diseases in elderly adults.


Assuntos
Bactérias , Fungos , Nível de Saúde , Serviços de Assistência Domiciliar , Microbiota , Boca , Humanos , Idoso , Feminino , Masculino , Idoso de 80 Anos ou mais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fungos/genética , Fungos/classificação , Fungos/isolamento & purificação , Boca/microbiologia , RNA Ribossômico 16S/genética , Saúde Bucal
7.
BMC Microbiol ; 24(1): 291, 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39097685

RESUMO

BACKGROUND: Taxol, derived from Taxus trees, is a valuable natural resource for the development of anticancer drugs. Endophytic fungi from Taxus trees are a promising alternative source of Taxol. However, the impact of plant-endophytic microbial interaction on the host's Taxol biosynthesis is largely unknown. RESULTS: In the current study, the diversity of endophytic fungi in three different Taxus species was analyzed using Internal Transcribed Spacer sequencing. A total of 271 Operational Taxonomic Units (OTUs) were identified, grouping into 2 phyla, 8 classes, 16 orders, 19 families, and 19 genera. Alpha and beta diversity analysis indicated significant differences in endophytic fungal communities among the various Taxus trees. At the genus level, Alternaria and Davidiella were predominantly found in T. mairei and T. media, respectively. By utilizing a previously published dataset, a Pearson correlation analysis was conducted to predict the taxol biosynthesis-related fungal genera. Following screening, two isolates of Alternaria (L7 and M14) were obtained. Effect of inoculation with Alternaria isolates on the gene expression and metabolite accumulation of T. mairei was determined by transcriptomic and untargeted metabolomic studies. The co-inoculation assay suggests that the two Alternaria isolates may have a negative regulatory effect on taxol biosynthesis by influencing hormone signaling pathways. CONCLUSION: Our findings will serve as a foundation for advancing the production and utilization of Taxus and will also aid in screening endophytic fungi related to taxol production.


Assuntos
Alternaria , Endófitos , Paclitaxel , Taxus , Taxus/microbiologia , Paclitaxel/biossíntese , Endófitos/genética , Endófitos/metabolismo , Endófitos/isolamento & purificação , Endófitos/classificação , Alternaria/genética , Alternaria/metabolismo , Alternaria/classificação , Alternaria/isolamento & purificação , Filogenia , Fungos/genética , Fungos/metabolismo , Fungos/classificação , Fungos/isolamento & purificação , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética
8.
Mol Ecol ; 33(9): e17342, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38584356

RESUMO

Endosymbiotic dinoflagellates (Symbiodiniaceae) influence coral thermal tolerance at both local and regional scales. In isolation, the effects of host genetics, environment, and thermal disturbances on symbiont communities are well understood, yet their combined effects remain poorly resolved. Here, we investigate Symbiodiniaceae across 1300 km in Australia's Coral Sea Marine Park to disentangle these interactive effects. We identified Symbiodiniaceae to species-level resolution for three coral species (Acropora cf humilis, Pocillopora verrucosa, and Pocillopora meandrina) by sequencing two genetic markers of the symbiont (ITS2 and psbAncr), paired with genotype-by-sequencing of the coral host (DArT-seq). Our samples predominantly returned sequences from the genus Cladocopium, where Acropora cf humilis affiliated with C3k, Pocillopora verrucosa with C. pacificum, and Pocillopora meandrina with C. latusorum. Multivariate analyses revealed that Acropora symbionts were driven strongly by local environment and thermal disturbances. In contrast, Pocillopora symbiont communities were both partitioned 2.5-fold more by host genetic structure than by environmental structure. Among the two Pocillopora species, the effects of environment and host genetics explained four times more variation in symbionts for P. meandrina than P. verrucosa. The concurrent bleaching event in 2020 had variable impacts on symbiont communities, consistent with patterns in P. verrucosa and A. cf humilis, but not P. meandrina. Our findings demonstrate how symbiont macroscale community structure responses to environmental gradients depend on host species and their respective population structure. Integrating host, symbiont, and environmental data will help forecast the adaptive potential of corals and their symbionts amidst a rapidly changing environment.


Assuntos
Antozoários , Recifes de Corais , Dinoflagellida , Simbiose , Dinoflagellida/genética , Simbiose/genética , Animais , Antozoários/microbiologia , Antozoários/genética , Austrália , Temperatura , Filogenia
9.
Mol Phylogenet Evol ; 197: 108092, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38723790

RESUMO

An acid-neutralizing, filamentous, non-heterocytous, marine cyanobacterium named 'LK' has been isolated from the seashore of Bangaram Island, an atoll of Lakshadweep, India, and is described here as a novel species. LK has been characterized using morphological, ecological, and genomic features. Based on 16S rRNA, whole-genome sequencing, and marker gene-based analysis, LK has been identified as a new species. LK clustered with Leptolyngbya-like strains belonging to the LPP group but diverged from Leptolyngbya sensu stricto, indicating the polyphyletic nature of the Leptolyngbya genus. Leptolyngbya sp. SIOISBB and Halomicronema sp. CCY15110 were identified as LK's two closest phylogenetic neighbors in various phylogenetic studies. The analysis of 16S rRNA, ITS secondary structures, and genome relatedness indices such as AAI, ANI, and gANI strongly support LK as a novel species of the Leptolyngbya genus. The mechanism behind acid neutralization in LK has been delineated, attributing it to a surface phenomenon most likely due to the presence of salts of calcium, magnesium, sodium, and potassium. We name LK as Leptolyngbya iicbica strain LK which is a novel species with prominent acidic pH-neutralizing properties.


Assuntos
Cianobactérias , Filogenia , RNA Ribossômico 16S , Cianobactérias/genética , Cianobactérias/classificação , RNA Ribossômico 16S/genética , Índia , Ilhas , DNA Bacteriano/genética , Água do Mar/microbiologia , Genoma Bacteriano/genética , Análise de Sequência de DNA
10.
Histopathology ; 84(4): 702-706, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38192085

RESUMO

AIMS: Mucormycosis is a fast-progressing disease with a high mortality rate. The most important factor determining survival of patients is early and accurate diagnosis. Although histopathology often recognises invasive mould infections at first, histomorphology alone is insufficient in providing an accurate diagnosis. Unbiased molecular methods to detect and identify fungi are promising, yet their role in complementing routine histopathological workflows has not been studied sufficiently. METHODS AND RESULTS: We performed a retrospective single-centre study examining the clinical value of complementing histopathology with internal transcribed spacer (ITS) sequencing of fungal DNA in the routine diagnosis of mucormycosis. At our academic centre, we identified 14 consecutive mucormycosis cases diagnosed by histopathology and subsequent ITS sequencing. Using histomorphological examination, fungal hyphae could be detected in all cases; however, morphological features were unreliable regarding specifying the taxa. Subsequent ITS sequencing identified a remarkable phylogenetic diversity among Mucorales: the most common species was Rhizopus microsporus (six of 14; 42.9%), followed by Lichtheimia corymbifera (three of 14, 21.4%) and single detections of Rhizopus oryzae, Actinomucor elegans, Mucor circinelloides, Rhizomucor pusillus and Rhizomucor miehei (one of 14; 7.1%, respectively). In one case, we additionally detected Pneumocystis jirovecii in the same lung tissue specimen, suggesting a clinically relevant co-infection. Fungal culture was performed in 10 cases but yielded positive results in only two of 10 (20%), revealing its limited value in the diagnosis of mucormycosis. CONCLUSIONS: Our study demonstrates that a combination of histopathology and ITS sequencing is a practically feasible approach that outperforms fungal culture in detecting Mucorales in tissue-associated infections. Therefore, pathologists might adapt diagnostic workflows accordingly when mucormycosis is suspected.


Assuntos
Mucormicose , Humanos , Mucormicose/diagnóstico , Mucormicose/microbiologia , Mucormicose/patologia , Estudos Retrospectivos , Filogenia
11.
Genetica ; 152(1): 51-61, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38381186

RESUMO

Chamaecrista is a Pantropical legume genus of the tribe Cassieae, which includes six other genera. In contrast to most of the other Cassieae genera, Chamaecrista shows significant variability in chromosome number (from 2n = 14 to 2n = 56), with small and morphologically similar chromosomes. Here, we performed a new cytomolecular analysis on chromosome number, genome size, and rDNA site distribution in a molecular phylogenetic perspective to interpret the karyotype trends of Chamaecrista and other two genera of Cassieae, seeking to understand their systematics and evolution. Our phylogenetic analysis revealed that Chamaecrista is monophyletic and can be divided into four major clades corresponding to the four sections of the genus. Chromosome numbers ranged from 2n = 14, 16 (section Chamaecrista) to 2n = 28 (sections Absus, Apoucouita, and Baseophyllum). The number of 5S and 35S rDNA sites varied between one and three pairs per karyotype, distributed on different chromosomes or in synteny, with no obvious phylogenetic significance. Our data allowed us to propose x = 7 as the basic chromosome number of Cassieae, which was changed by polyploidy generating x = 14 (sections Absus, Apoucouita, and Baseophyllum) and by ascending dysploidy to x = 8 (section Chamaecrista). The DNA content values supported this hypothesis, with the genomes of the putative tetraploids being larger than those of the putative diploids. We hypothesized that ascending dysploidy, polyploidy, and rDNA amplification/deamplification are the major events in the karyotypic diversification of Chamaecrista. The chromosomal marks characterized here may have cytotaxonomic potential in future studies.


Assuntos
Chamaecrista , Fabaceae , Filogenia , Chamaecrista/genética , Fabaceae/genética , Cromossomos de Plantas/genética , Genoma de Planta , Cariótipo , Poliploidia , DNA Ribossômico/genética
12.
Arch Microbiol ; 206(2): 66, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227204

RESUMO

Brown rot Polypores are ecologically significant as they play a crucial role in maintaining the carbon cycle and contribute to humus formation in forest ecosystems through their lignocellulose degradation ability. It is important to note that some species can significantly impact timber, potentially causing decay in economically valuable wood. Many Asian countries including Pakistan are still under the exploratory phase and have undocumented species diversity in Polypore fungi. In the current study, collections representing five different species belonging to two families, Postiaceae and Adustoporiaceae, were subjected to detailed morphoanatomical and molecular analyses. A combined matrix of two gene datasets (ITS and nrLSU) was analyzed using three different phylogenetic methods viz. Maximum Parsimony (MP), Maximum Likelihood (ML), and Bayesian inference (BI). Our study presents descriptions of five previously undocumented brown rot Polypore species from the country including Fuscopostia fragilis (Fr.) B.K. Cui, L.L. Shen & Y.C. Dai, Amaropostia stiptica (Pers.) B.K. Cui, L.L. Shen & Y.C. Dai, Cyanosporus piceicola B.K. Cui, L.L. Shen & Y.C. Dai, Spongiporus balsameus (Peck) A. David, Rhodonia placenta (Fr.) Niemelä, K.H. Larss. & Schigel. Regarding the molecular data, nodes of our subject sequences were substantially supported and fell under their respective species clades with high ML bootstrap values (≥ 95), MP bootstrap ≥ 74 and BI probabilities ≥ 0.98. Findings of the study will not only contribute to our understanding of local Polypores species diversity but also enhance knowledge of geographical distribution in global context.


Assuntos
Ciclo do Carbono , Ecossistema , Humanos , Paquistão , Teorema de Bayes , Filogenia
13.
Arch Microbiol ; 206(4): 157, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480543

RESUMO

Potassium-solubilizing microorganisms are capable of secreting acidic chemicals that dissolve and release potassium from soil minerals, thus facilitating potassium uptake by plants. In this study, three potassium-dissolving filamentous fungi were isolated from the rhizosphere soil of a poplar plantation in Jiangsu Province, China. Phylogenetic analyses based on ITS, 18 S, and 28 S showed that these three isolates were most similar to Mortierella. These strains also possessed spherical or ellipsoidal spores, produced sporangia at the hyphal tip, and formed petal-like colonies on PDA media resembling those of Mortierella species. These findings, along with further phenotypic observations, suggest that these isolates were Mortierella species. In addition, the potassium-dissolution experiment showed that strain 2K4 had a relatively high potassium-solubilizing capacity among these isolated fungi. By investigating the influences of different nutrient conditions (carbon source, nitrogen source, and inorganic salt) and initial pH values on the potassium-dissolving ability, the optimal potassium-solubilization conditions of the isolate were determined. When potassium feldspar powder was used as an insoluble potassium source, isolate 2K4 exhibited a significantly better polysaccharide aggregation ability on the formed mycelium-potassium feldspar complex. The composition and content of organic acids secreted by strain 2K4 were further detected, and the potassium-dissolution mechanism of the Mortierella species and its growth promotion effect were discussed, using maize as an example.


Assuntos
Silicatos de Alumínio , Mortierella , Compostos de Potássio , Solo , Solo/química , Fosfatos , Mortierella/genética , Potássio , Rizosfera , Filogenia , Microbiologia do Solo , Fungos
14.
Ann Bot ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39113434

RESUMO

BACKGROUND AND AIMS: The Labrador Teas (genus Rhododendron, subsection Ledum) are a complex of species widely distributed in the Northern Hemisphere. They occupy cold-resistant plant communities from highlands to forest understory and wetland habitats almost circumboreally and they are especially abundant in Northeast Asia (NE Asia) and northern North America (NN Am), still there are no clear species boundaries in this group. The genetic structure of species of the subsect. Ledum from Eurasia and North America as well as the dispersal history of the group require clarification. METHODS: Phylogeny and biogeography of the subsect. Ledum of the genus Rhododendron were assessed using phylogenetic trees constructed based on the analysis of variation in chloroplast petB-petD, trnV-ndhC, trnH-psbA, K2R-K707, atpB oligo2 - rbcL oligo5 and nuclear (ITS1) markers of four Eurasian and one American species (65 populations, 408 individuals). The data were evaluated with Maximum Parsimony and Bayesian analysis. Molecular dating and ancestral areas reconstruction were obtained. KEY RESULTS: Dense sampling revealed widespread presence of shared haplotypes and ribotypes among Ledum populations and species. Two American, three Eurasian and one mixed lineage diversified during the Neogene climate cooling and then rapidly dispersed during the Pleistocene. The ability to accumulate high genetic diversity and to preserve it across distribution ranges and generations prevented Ledum from lineage sorting. As a result, a species complex with a reserve of genetic variability appeared. CONCLUSIONS: Although no clear phylogenetic inference can be obtained at present, the plastid genealogy is consisted with the nuclear genealogy and demonstrates the processes involved in speciation in the Ledum species complex.

15.
J Eukaryot Microbiol ; : e13058, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39252569

RESUMO

Glugea sp. found infecting the liver of the teleost fish Carangoides bajad from the Red Sea, Egypt, is described based on light microscopy and ultrastructural characteristics combined with phylogenetic analyses. This microsporidium forms whitish xenomas up to ~4 mm in size. Xenomas display numerous parasitophorous vacuoles totally filled by mature spores, no other life cycle stages were observed. Mature spores ellipsoidal and measuring 6.3 × 4.0 µm in size. The polaroplast appears composed of two distinct regions: an electron-dense vesicular region and a densely packed lamellar region. The polar tubule forms approximately 24-27 coils arranged in three layers encircling the posterior vacuole. The small subunit (SSU) rRNA gene and its ITS region were sequenced and showed the highest similarity of 99.4% to other Glugea spp. Bayesian inference and maximum likelihood analyses place the novel isolate within the Glugea clade, more specifically within a subclade that predominantly grouped species described from fish inhabiting the Arabian Gulf or Red Sea. The results validate the parasite's classification in the Glugea genus. Nevertheless, until more detailed ultrastructural and molecular data are obtained, the identification of the current Glugea species is hampered by the absence of some developmental stages and the high degree of genetic similarity.

16.
Med Mycol ; 62(7)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38857886

RESUMO

Acrophialophora is implicated in superficial and invasive infections, especially in immunosuppressed individuals. The present study was undertaken to provide clinical, microbiological, phylogenetic, and antifungal susceptibility testing (AFST) profile of Acrophialophora isolated from India. All the isolates identified as Acrophialophora species at the National Culture Collection for Pathogenic Fungi, Chandigarh, India were revived. Phenotypic and molecular characterization was performed, followed by temperature studies, scanning electron microscopy (SEM), and AFST. We also performed systematic review of all the cases of Acrophialophora species reported till date. A total of nine isolates identified as Acrophialophora species were identified by molecular method as A. fusispora (n = 8) and A. levis (n = 1), from brain abscess (n = 4), respiratory tract (n = 3), and corneal scraping (n = 2). All patients but two had predisposing factors/co-morbidities. Acrophialophora was identified as mere colonizer in one. Temperature studies and SEM divulged variation between both species. Sequencing of the internal transcribed spacer ribosomal DNA and beta-tubulin loci could distinguish species, while the LSU ribosomal DNA locus could not. AFST showed the lowest minimum inhibitory concentrations (MICs) for triazoles and the highest for echinocandins. Systematic literature review revealed 16 cases (11 studies), with ocular infections, pulmonary and central nervous system infections, and A. fusispora was common species. All the patients except three responded well. High MICs were noted for fluconazole, micafungin, and caspofungin. This is the first study delineating clinical, phenotypic, and genotypic characteristics of Acrophialophora species from India. The study highlights microscopic differences between both species and emphasizes the role of molecular methods in precise identification. Triazoles appear to be the most effective antifungals for managing patients.


We describe clinical, phenotypic, and genotypic characteristics of Acrophialophora species. This species causes mild infection to fatal infection in immunosuppressed individuals. Triazoles are effective in treating such infections.


Assuntos
Antifúngicos , Testes de Sensibilidade Microbiana , Micoses , Filogenia , Índia , Humanos , Antifúngicos/farmacologia , Adulto , Masculino , Micoses/microbiologia , Feminino , Pessoa de Meia-Idade , Ascomicetos/efeitos dos fármacos , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Ascomicetos/classificação , DNA Fúngico/genética , Análise de Sequência de DNA , DNA Espaçador Ribossômico/genética , Microscopia Eletrônica de Varredura , Fenótipo , Tubulina (Proteína)/genética , Idoso , Adulto Jovem , Criança
17.
Med Mycol ; 62(8)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39104225

RESUMO

Epizootic lymphangitis (EL) is a highly prevalent and contagious infectious disease affecting horses in many parts of Ethiopia caused by Histoplasma capsulatum sensu lato ('var. farciminosum'). In this study, 12 suspected isolates of H. capsulatum sensu lato or yeasts unidentified by conventional biochemical tests isolated from Ethiopian horses with EL were characterised by internal transcribed spacer sequencing. Six of the 12 isolates were identified to be members of H. capsulatum sensu lato and the other six were Pichia kudriavzevii (synonym: Candida krusei) (n = 3), Trichosporon asahii (n = 1), Geotrichum silvicola (n = 1) and Moesziomyces aphidis (n = 1), respectively. The six H. capsulatum sensu lato isolates were further characterised by multilocus sequence analysis. Four distinct gene loci (arf [462 bases], H-anti [410 bases], ole1 [338 bases] and tub1 [272 bases]) of these six isolates as well as those of two H. capsulatum sensu lato ('var. farciminosum') reference strains (ATCC 58332 and ATCC 28798) were polymerase chain reaction (PCR)-amplified and sequenced. Phylogenetic analyses of their concatenated nucleotide sequences showed that three of the isolates and the reference strain ATCC 58332 were identical and belonged to the Eurasia clade within Latin American (LAm) A (H. suramericanum), and those of the other three isolates and the reference strain ATCC 28798 were identical and belonged to the Africa clade. At least two distinct phylogenetic clades of H. capsulatum sensu lato were circulating in Ethiopian horses with EL. Advanced molecular technologies and bioinformatics tools are crucial for the accurate identification and typing of pathogens as well as the discovery of novel microorganisms in veterinary microbiology.


Using multilocus sequence analysis with four concatenated housekeeping gene loci, at least two distinct phylogenetic clades, namely Eurasia clade and Africa clade, of Histoplasma capsulatum sensu lato were confirmed to be circulating in Ethiopian horses with epizootic lymphangitis.


Assuntos
DNA Fúngico , Histoplasma , Histoplasmose , Doenças dos Cavalos , Tipagem de Sequências Multilocus , Filogenia , Animais , Histoplasma/genética , Histoplasma/classificação , Histoplasma/isolamento & purificação , Etiópia , Histoplasmose/microbiologia , Histoplasmose/veterinária , Cavalos/microbiologia , Doenças dos Cavalos/microbiologia , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Análise de Sequência de DNA , Técnicas de Tipagem Micológica
18.
Med Mycol ; 62(7)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38816207

RESUMO

Candida auris represents one of the most urgent threats to public health, although its ecology remains largely unknown. Because amphibians and reptiles may present favorable conditions for C. auris colonization, cloacal and blood samples (n = 68), from several snake species, were cultured and molecularly screened for C. auris using molecular amplification of glycosylphosphatidylinositol protein-encoding genes and ribosomal internal transcribed spacer sequencing. Candida auris was isolated from the cloacal swab of one Egyptian cobra (Naja haje legionis) and molecularly identified in its cloaca and blood. The isolation of C. auris from wild animals is herein reported for the first time, thus suggesting the role that these animals could play as reservoirs of this emerging pathogen. The occurrence of C. auris in blood requires further investigation, although the presence of cationic antimicrobial peptides in the plasma of reptiles could play a role in reducing the vitality of the fungus.


Candida auris represents one of the most urgent threats to public health. In this study, we reported for the first time the isolation of C. auris from snake thus suggesting the role of these animals as reservoirs of this emerging pathogen.


Assuntos
Candida , Candidíase , DNA Espaçador Ribossômico , Reservatórios de Doenças , Animais , Candida/genética , Candida/classificação , Candida/isolamento & purificação , Candida/efeitos dos fármacos , Reservatórios de Doenças/microbiologia , Candidíase/microbiologia , Candidíase/veterinária , DNA Espaçador Ribossômico/genética , DNA Espaçador Ribossômico/química , Cloaca/microbiologia , Análise de Sequência de DNA , DNA Fúngico/genética , Sangue/microbiologia , Serpentes/microbiologia , Elapidae , Egito , Filogenia
19.
BMC Infect Dis ; 24(1): 724, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044181

RESUMO

BACKGROUND: The Anopheles hyrcanus group is distributed throughout the Oriental and Palaearctic regions and can transmit diseases such as malaria, Japanese encephalitis virus, and filariasis. This investigation marks the inaugural comprehensive study to undertake a phylogenetic analysis of the constituents of this malaria vector group in the northeastern region of Iran, juxtaposed with documented occurrences from different areas within Iran and worldwide. METHODS: Mosquitoes were collected using various methods from nine different locations in Golestan province from April to December 2023. The collected mosquitoes were identified morphologically using valid taxonomic keys. DNA was isolated using the Sambio™ Kit. COI and ITS2 primers were designed using Oligo7 and GeneRunner. PCR and purification were performed with the Qiagen kit. Subsequently, sequencing was carried out at the Mehr Mam GENE Center using an Applied Biosystems 3730XL sequencer. The nucleotide sequences were then analyzed and aligned with GenBank data using BioEdit. Kimura 2-parameter was Utilized for base substitutions. DNA models were selected based on AIC and BIC criteria. Bayesian and Maximum Likelihood trees were constructed, along with a haplotype network. Molecular diversity statistics computed using DnaSP software. RESULTS: In this study, a total of 819 adult mosquitoes were collected. An. hyrcanus was the second most abundant species, predominantly found in Kalaleh and Turkman counties. The sequenced and edited COI and ITS2 sequences were deposited in GenBank under specific accession numbers. Phylogenetic analyses using ML, BI, and NJ methods confirmed a monophyletic lineage for An. hyrcanus with strong support. Molecular analysis of Iranian An. hyrcanus found 11 diverse haplotypes, with the COI gene displaying low diversity. The ITS2 gene revealed two clades - one associating with Iran, Europe, and Asia; the other originating from southwestern Iran. The haplotype network showed two main groups - one from southwest Iran and the other from north Iran. Iran exhibited six distinct haplotypes, while Turkey showcased the highest diversity. CONCLUSIONS: An. hyrcanus in southwestern Iran exhibits a distinct haplogroup, suggesting possible subspecies differentiation. Additional studies are required to validate this phenomenon.


Assuntos
Anopheles , Complexo IV da Cadeia de Transporte de Elétrons , Mosquitos Vetores , Filogenia , Animais , Irã (Geográfico) , Anopheles/genética , Anopheles/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Mosquitos Vetores/genética , Mosquitos Vetores/classificação , Haplótipos , Variação Genética , Genética Populacional , Análise de Sequência de DNA , DNA Espaçador Ribossômico/genética
20.
Mol Biol Rep ; 51(1): 668, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38787488

RESUMO

BACKGROUND: The species of genus Ageratum (family Asteraceae) are distributed in various parts of the world. Ageratum conyzoides and A. houstonianum are the most commonly occurring species in India. These species are quite similar in their morphology thus creating a challenge in identification during the field survey and taxonomic validation. The accurate identification of the species is highly significant especially when those are of medicinal interest. To overcome the barriers in morphological based identification, DNA barcoding has been employed during the present investigation. METHODS AND RESULTS: Morphological and DNA barcodes matK and ITS genes, were employed to differentiate between Ageratum conyzoides and A. houstonianum. The obtained matK and ITS gene sequences were submitted to GenBank and BOLD system to obtain accession numbers. The DNA sequences were aligned with database sequences using BLAST and phylogenetic trees were constructed through neighbor-joining algorithm in MEGA 11 software. The distinguish features of A. conyzoides include ovate to elliptic-oblong leaves with a cuneate base and inflorescence heads forming domed to flat-topped clusters. However, A. houstonianum has triangular to ovate leaves with a cordate to truncate base, cymose clusters in the inflorescence and stipulate glandular involucre bracts. The matK gene has shown the highest identity percentages (100%) for A. houstonianum and 99.87% for A. conyzoides. The phylogenetic tree analysis has demonstrated a close association of A. conyzoides and A. houstonianum with their respective species, supported by bootstrap values in the matK and ITS trees. CONCLUSION: This study revealed that morphological and molecular data can be successfully utilized in the identification of A. conyzoides and A. houstonianum. The matK and ITS barcodes provide promising results in the identification of Ageratum species, with their phylogeny supporting classification within the family asteraceae.


Assuntos
Ageratum , Código de Barras de DNA Taxonômico , Filogenia , Código de Barras de DNA Taxonômico/métodos , Ageratum/genética , DNA de Plantas/genética , Folhas de Planta/genética , Análise de Sequência de DNA/métodos , Índia
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