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1.
BMC Bioinformatics ; 25(1): 228, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956506

ABSTRACT

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 .


Subject(s)
Fungi , Machine Learning , Fungi/genetics , Fungi/classification , DNA, Ribosomal Spacer/genetics , Software
2.
Yeast ; 41(1-2): 52-63, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38146767

ABSTRACT

In this study, we describe Nakazawaea atacamensis f. a., sp. nov., a novel species obtained from Neltuma chilensis plant samples in Chile's hyperarid Atacama Desert. In total, three strains of N. atacamensis were obtained from independent N. chilensis samples (synonym Prosopis chilensis, Algarrobo). Two strains were obtained from bark samples, while the third strain was obtained from bark-exuded gum from another tree. The novel species was defined using molecular characteristics and subsequently characterized with respect to morphological, physiological, and biochemical properties. A neighbor-joining analysis using the sequences of the D1/D2 domains of the large subunit ribosomal RNA gene revealed that N. atacamensis clustered with Nakazawaea pomicola. The sequence of N. atacamensis differed from closely related species by 1.3%-5.2% in the D1/D2 domains. A phylogenomic analysis based on single-nucleotide polymorphism's data confirms that the novel species belongs to the genus Nakazawaea, where N. atacamensis clustered with N. peltata. Phenotypic comparisons demonstrated that N. atacamensis exhibited distinct carbon assimilation patterns compared to its related species. Genome sequencing of the strain ATA-11A-BT revealed a genome size of approximately 12.4 Mbp, similar to other Nakazawaea species, with 5116 protein-coding genes annotated using InterProScan. In addition, N. atacamensis exhibited the capacity to ferment synthetic wine must, representing a potential new yeast for mono or co-culture wine fermentations. This comprehensive study expands our understanding of the genus Nakazawaea and highlights the ecological and industrial potential of N. atacamensis in fermentation processes. The holotype of N. atacamensis sp. nov. is CBS 18375T . The Mycobank number is MB 849680.


Subject(s)
Saccharomycetales , Wine , Fermentation , Phylogeny , Saccharomycetales/genetics , Pichia/genetics , Base Sequence , Sequence Analysis, DNA , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics
3.
Mol Phylogenet Evol ; 196: 108084, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38688440

ABSTRACT

The tribe Collabieae (Epidendroideae, Orchidaceae) comprises approximately 500 species. Generic delimitation within Collabieae are confusing and phylogenetic interrelationships within the Collabieae have not been well resolved. Plastid genomes and nuclear internal transcribed spacer (ITS) sequences were used to estimate the phylogenetic relationships, ancestral ranges, and diversification rates of Collabieae. The results showed that Collabieae was subdivided into nine clades with high support. We proposed to combine Ancistrochilus and Pachystoma into Spathoglottis, merge Collabium and Chrysoglossum into Diglyphosa, and separate Pilophyllum and Hancockia as distinctive genera. The diversification of the nine clades of Collabieae might be associated with the uplift of the Himalayas during the Late Oligocene/Early Miocene. The enhanced East Asian summer monsoon in the Late Miocene may have promoted the rapid diversification of Collabieae at a sustained high diversification rate. The increased size of terrestrial pseudobulbs may be one of the drivers of Collabieae diversification. Our results suggest that the establishment and development of evergreen broadleaved forests facilitated the diversification of Collabieae.


Subject(s)
Orchidaceae , Phylogeny , Orchidaceae/genetics , Orchidaceae/classification , Forests , Genome, Plastid/genetics , Phylogeography , DNA, Ribosomal Spacer/genetics , Sequence Analysis, DNA , Asia , DNA, Plant/genetics
4.
Article in English | MEDLINE | ID: mdl-38591772

ABSTRACT

Two yeast strains, designated as 19-39-3 and 19-40-2, obtained from the fruiting bodies of Trametes versicolor and Marasmius siccus collected in Yunwu Mountain Forest Park, PR China, have been identified as representing a novel asexual ascomycetous yeast species. From the results of phylogenetic analyses of the sequences of the D1/D2 domains of the large subunit (LSU) rRNA, small subunit (SSU) rRNA and translation elongation factor 1-α (TEF1) genes, it was determined that these strains represent a member of the genus Wickerhamomyces, with Wickerhamomyces alni and Candida ulmi as the closest relatives. The novel species exhibited 6.6 and 6.7% differences in the D1/D2 domains compared with W. alni and C. ulmi, respectively. Additionally, distinct biochemical and physiological differences were observed between the novel species and its related counterparts. No sexual reproduction was observed in these strains, leading to the proposal of the name Wickerhamomyces corioli f.a., sp. nov. for this newly discovered species.


Subject(s)
Agaricales , Saccharomycetales , Phylogeny , DNA, Ribosomal Spacer/genetics , Agaricales/genetics , Trametes/genetics , Sequence Analysis, DNA , Base Composition , RNA, Ribosomal, 16S/genetics , DNA, Bacterial/genetics , Bacterial Typing Techniques , Fatty Acids/chemistry , Saccharomycetales/genetics , DNA, Fungal/genetics , Mycological Typing Techniques
5.
Article in English | MEDLINE | ID: mdl-38591773

ABSTRACT

Four yeast strains, representing a novel anamorphic species, were isolated in Thailand. The two strains (ST-3660T and ST-3647) were obtained from two different estuarine water samples in a mangrove forest. Strain DMKU-FW1-37 was derived from a grease sample, and another strain (TSU57) was isolated from a fruiting body of Phallus sp. Pairwise sequence analysis showed that the four strains had identical or differed by only one nucleotide substitution in the D1/D2 domains of the large subunit (LSU) rRNA gene, and differed by one to three nucleotide substitutions in the internal transcribed spacer (ITS) regions. Savitreea pentosicarens is the most closely related species to the four strains, but with 9-10 (1.57-1.72 %) nucleotide substitutions in the D1/D2 domains of the LSU rRNA gene and 29-31 (4.22-4.45 %) nucleotide substitutions in the ITS regions. Phylogenetic analyses based on the concatenated sequences of the ITS regions and the D1/D2 domains of the LSU rRNA gene showed that the four strains form a well-separated lineage from S. pentosicarens with high bootstrap support, confirming that they represent a distinct species. Therefore, the four strains are assigned as representives of a novel species of the genus Savitreea, for which the name Savitreea siamensis sp. nov. is proposed. The holotype is TBRC 4481T and the ex-type is PYCC 9794T (=ST-3660T). The MycoBank number of the novel species is MB 851951.


Subject(s)
Fatty Acids , Saccharomycetales , Phylogeny , DNA, Ribosomal Spacer/genetics , Thailand , Sequence Analysis, DNA , DNA, Fungal/genetics , Mycological Typing Techniques , RNA, Ribosomal, 16S/genetics , DNA, Bacterial/genetics , Bacterial Typing Techniques , Base Composition , Fatty Acids/chemistry , Nucleotides
6.
Article in English | MEDLINE | ID: mdl-38713196

ABSTRACT

The genus Exophiala is polymorphic, able to transition between yeast, hyphal and pseudohyphal forms. Species of the genus Exophiala are ubiquitous fungi that are distributed in various environments around the world. During a survey of fungal diversity in the gut of amphipods (Floresorchestia amphawaensis and undescribed Dogielinotid amphipods) from the Amphawa estuary, Samut Songkhram province, Thailand, five black yeast strains (DMKU-MG01, DMKU-MG07, DMKU-MG08, DMKU-HG10 and DMKU-FG04) were identified as representing a novel taxon on the basis of a combination of morphological and molecular phylogenetic features. The five strains did not produce filamentous hyphae or pseudohyphae. Only budding yeast cells were observed. On the basis of the phenotypic characteristics and the results of molecular analyses of the D1/D2 region of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region, the five strains were identified as representing a novel species via applied nucleotide pairwise analysis. They differed from the most closely related species Exophiala alcalophiala by 3.54 % nucleotide substitutions (20 nucleotide substitutions in 572 bp) in the D1/D2 domains of the LSU rRNA gene. Moreover, the sequences of the ITS region of the five strains differed from those of the most closely related species E. alcalophiala, by 7.44-9.62 % nucleotide substitutions, and Exophiala halophiala, by 7.2-7.53 % nucleotide substitutions. The results of phylogenetic analyses based on the concatenated sequences of the ITS regions and the D1/D2 domains of the LSU rRNA gene confirmed that the five black yeast strains represented a single novel species of the genus Exophiala. In this study, Exophiala amphawaensis sp. nov. is proposed to accommodate these strains. The holotype is TBRC 15626T and the isotype is PYCC9020. The MycoBank accession number of the novel species is MB 851477.


Subject(s)
Amphipoda , DNA, Fungal , DNA, Ribosomal Spacer , Exophiala , Phylogeny , Sequence Analysis, DNA , Animals , Thailand , Amphipoda/microbiology , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Exophiala/genetics , Exophiala/isolation & purification , Exophiala/classification , Mycological Typing Techniques , Gastrointestinal Tract/microbiology
7.
Article in English | MEDLINE | ID: mdl-38713197

ABSTRACT

Two isolates representing a novel species of the genus Wickerhamiella were obtained in India from nectar of flowers of Lantana camara, an ornamental exotic species native to Central and South America. Phylogenetic analyses of the D1/D2 domain of the 26S large subunit (LSU) rRNA gene, internal transcribed spacer (ITS) region, and physiological characteristics, supported the recognition of the novel species, that we designate Wickerhamiella lachancei sp. nov (MycoBank no. MB851709), with MCC 9929T as the holotype and PYCC 10003T as the isotype. Considering pairwise sequence similarity, the type strain of the novel species differs from the type strain of the most closely related species, Wickerhamiella drosophilae CBS 8459T, by 16 nucleotide substitutions and two gaps (3.9 % sequence variation) in the D1/D2 region (560 bp compared) and 28 nucleotide substitutions and five gaps (7.22 % sequence variation) in the ITS region (444 bp compared).


Subject(s)
DNA, Fungal , DNA, Ribosomal Spacer , Flowers , Lantana , Phylogeny , Sequence Analysis, DNA , India , Flowers/microbiology , DNA, Fungal/genetics , Lantana/microbiology , DNA, Ribosomal Spacer/genetics , Molecular Sequence Data , Mycological Typing Techniques , RNA, Ribosomal/genetics , Saccharomycetales/genetics , Saccharomycetales/isolation & purification , Saccharomycetales/classification
8.
Article in English | MEDLINE | ID: mdl-38284408

ABSTRACT

Three yeast isolates, NBRC 115909T, NBRC 115910 and NBRC 116270, were isolated from Trifolium pratense (red clover) flowers collected from Kisarazu, Chiba, Japan. Analysis of the sequences of the D1/D2 domains of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) regions revealed that these isolates represent a single novel species within the genus Starmerella. Also, no ascospore formation was observed. The yeast isolates were closely related to Starmerella vitae UWOPS 00-107.2T and Starmerella bombi NRRL Y-17081T. They differed from S. vitae, the most closely related species with a validly published name, by ten nucleotide substitutions with two gaps in the D1/D2 domains and 20 nucleotide substitutions in the ITS region. Moreover, the three isolates exhibited distinct phenotypic characteristics from the closely related species. Therefore, we suggest that these three isolates represent a novel species, designated as Starmerella kisarazuensis f.a., sp. nov. The holotype is NBRC 115909T (isotype: CBS 18485T).


Subject(s)
Saccharomycetales , Trifolium , Trifolium/genetics , Phylogeny , DNA, Fungal/genetics , Mycological Typing Techniques , Sequence Analysis, DNA , Base Composition , RNA, Ribosomal, 16S/genetics , DNA, Bacterial/genetics , Bacterial Typing Techniques , Fatty Acids/chemistry , Saccharomycetales/genetics , Flowers , Nucleotides , DNA, Ribosomal Spacer/genetics , Thailand
9.
Article in English | MEDLINE | ID: mdl-38359077

ABSTRACT

Three yeast isolate candidates for a novel species were obtained from rotting wood samples collected in Brazil and Colombia. The Brazilian isolate differs from the Colombian isolates by one nucleotide substitution in each of the D1/D2 and small subunit (SSU) sequences. The internal transcribed spacer (ITS) and translation elongation factor 1-α gene sequences of the three isolates were identical. A phylogenetic analysis showed that this novel species belongs to the genus Ogataea. This novel species is phylogenetically related to Candida nanaspora and Candida nitratophila. The novel species differs from C. nanaspora by seven nucleotides and two indels, and by 17 nucleotides and four indels from C. nitratophila in the D1/D2 sequences. The ITS sequences of these three species differ by more than 30 nucleotides. Analyses of the sequences of the SSU and translation elongation factor 1-α gene also showed that these isolates represent a novel species of the genus Ogataea. Different from most Ogataea species, these isolates did not assimilate methanol as the sole carbon source. The name Ogataea nonmethanolica sp. nov. is proposed to accommodate these isolates. The holotype of Ogataea nonmethanolica is CBS 13485T. The MycoBank number is MB 851195.


Subject(s)
Peptide Elongation Factor 1 , Saccharomycetales , Peptide Elongation Factor 1/genetics , Brazil , Phylogeny , Colombia , DNA, Ribosomal Spacer/genetics , Wood , RNA, Ribosomal, 16S/genetics , DNA, Fungal/genetics , Mycological Typing Techniques , Sequence Analysis, DNA , DNA, Bacterial/genetics , Bacterial Typing Techniques , Base Composition , Fatty Acids/chemistry , Saccharomycetales/genetics , Nucleotides
10.
J Eukaryot Microbiol ; 71(4): e13039, 2024.
Article in English | MEDLINE | ID: mdl-38956983

ABSTRACT

The planktonic dinoflagellate Prorocentrum compressum is widespread in warm and temperate seas. A strain identified as P. cf. compressum BEA 0681B isolated from the island of Gran Canaria, NE Atlantic Ocean, showed a divergence in rDNA/ITS phylogenies with respect to P. compressum. The Canarian strain was oval, with an average length-to-width ratio of 1.35, smooth thecal surface with less than 150 thecal pores, including oblique pores, sometimes with a bifurcated opening. In contrast, P. compressum was rounder, with a length-to-width ratio < 1.2, with reticulate-foveate ornamentation and 200-300 pores per valve. We propose Prorocentrum canariense sp. nov. These species clustered as the most early-branching lineage in the clade Prorocentrum sensu stricto. Although this clade mainly contains planktonic species, the closer relatives were the benthic species P. tsawwassenense and P. elegans. Interestingly, P. compressum and P. canariense sp. nov. are widely distributed in temperate and warm seas without an apparent morphological adaptation to planktonic life. The formation of two concentric hyaline mucilaginous walls could contribute to this success. We discuss the use of Prorocentrum bidens to solve the nomenclature issue of P. compressum that was described citing a diatom as basionym.


Subject(s)
DNA, Protozoan , DNA, Ribosomal , Dinoflagellida , Phylogeny , Dinoflagellida/classification , Dinoflagellida/genetics , DNA, Ribosomal/genetics , DNA, Protozoan/genetics , Atlantic Ocean , Sequence Analysis, DNA , DNA, Ribosomal Spacer/genetics , DNA, Ribosomal Spacer/analysis , Molecular Sequence Data
11.
Med Mycol ; 62(3)2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38414255

ABSTRACT

Enterocytozoon bieneusi is a microsporidia commonly found in the gastrointestinal tract of humans and a wide range of other animals, constituting a major cause of microsporidiosis in humans. Although E. bieneusi has been detected in humans, domestic, and wild animals in Portugal, and its presence in bats has been linked to zoonotic characteristics, its occurrence in bats within the country has not been reported. In this study, we investigated the presence of E. bieneusi in 380 bat fecal samples collected in mainland Portugal through a nested PCR assay targeting the internal transcribed spacer region and the flanking small and large subunits of the ribosomal RNA. Enterocytozoon bieneusi was detected in one bat sample (i.e., 0.26%; Pipistrellus pipistrellus). Additionally, another sample tested positive for Enterocytozoon sp. Phylogenetic analysis of the obtained ITS sequence of E. bieneusi revealed clustering within the potentially zoonotic Group 1. This study represents the first report of E. bieneusi in a bat from Europe. Findings presented here contribute to an enhanced understanding of E. bieneusi epidemiology.


Enterocytozoon bieneusi is the most frequent cause of microsporidiosis in humans. In this study, E. bieneusi, belonging to a potentially zoonotic Group, was detected in 0.26% bat samples from Portugal, highlighting bats' potential role in transmitting this microsporidia to humans and other animals.


Subject(s)
Chiroptera , Enterocytozoon , Microsporidiosis , Animals , Humans , Enterocytozoon/genetics , Genotype , Portugal/epidemiology , Phylogeny , DNA, Ribosomal Spacer/genetics , Prevalence , Microsporidiosis/epidemiology , Microsporidiosis/veterinary , Feces , China/epidemiology
12.
Med Mycol ; 62(7)2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38816207

ABSTRACT

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.


Subject(s)
Candida , Candidiasis , DNA, Ribosomal Spacer , Disease Reservoirs , Animals , Candida/genetics , Candida/classification , Candida/isolation & purification , Candida/drug effects , Disease Reservoirs/microbiology , Candidiasis/microbiology , Candidiasis/veterinary , DNA, Ribosomal Spacer/genetics , DNA, Ribosomal Spacer/chemistry , Cloaca/microbiology , Sequence Analysis, DNA , DNA, Fungal/genetics , Blood/microbiology , Snakes/microbiology , Elapidae , Egypt , Phylogeny
13.
Med Mycol ; 62(7)2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38857886

ABSTRACT

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.


Subject(s)
Antifungal Agents , Microbial Sensitivity Tests , Mycoses , Phylogeny , India , Humans , Antifungal Agents/pharmacology , Adult , Male , Mycoses/microbiology , Female , Middle Aged , Ascomycota/drug effects , Ascomycota/genetics , Ascomycota/isolation & purification , Ascomycota/classification , DNA, Fungal/genetics , Sequence Analysis, DNA , DNA, Ribosomal Spacer/genetics , Microscopy, Electron, Scanning , Phenotype , Tubulin/genetics , Aged , Young Adult , Child
14.
Microb Ecol ; 87(1): 78, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38806848

ABSTRACT

Fungi contribute to different important ecological processes, including decomposition of organic matter and nutrient cycling, but in the marine environment the main factors influencing their diversity and dynamics at the spatial and temporal levels are still largely unclear. In this study, we performed DNA metabarcoding on seawater sampled monthly over a year and a half in the Gulf of Trieste (northern Adriatic Sea), targeting the internal transcribed spacer (ITS) and the 18S rRNA gene regions. The fungal communities were diverse, very dynamic, and belonged predominantly to marine taxa. Samples could be clustered in two groups, mainly based on the high (> 30%) or low relative proportion of the ascomycetes Parengyodontium album, which emerged as a key taxon in this area. Dissolved and particulate organic C:N ratio played important roles in shaping the mycoplankton assemblages, suggesting that differently bioavailable organic matter pools may be utilized by different consortia. The proportion of fungal over total reads was 31% for ITS and 0.7% for 18S. ITS had the highest taxonomic resolution but low power to detect early divergent fungal lineages. Our results on composition, distribution, and environmental drivers extended our knowledge of the structure and function of the mycobiome of coastal waters.


Subject(s)
Biodiversity , Fungi , RNA, Ribosomal, 18S , Seawater , Seawater/microbiology , Fungi/genetics , Fungi/classification , Fungi/isolation & purification , RNA, Ribosomal, 18S/genetics , RNA, Ribosomal, 18S/analysis , Mycobiome , DNA, Fungal/genetics , DNA Barcoding, Taxonomic , Phylogeny , DNA, Ribosomal Spacer/genetics , DNA, Ribosomal Spacer/analysis , Ascomycota/genetics , Ascomycota/classification , Ascomycota/isolation & purification
15.
Mol Biol Rep ; 51(1): 639, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38727924

ABSTRACT

BACKGROUND: Peucedani Radix, also known as "Qian-hu" is a traditional Chinese medicine derived from Peucedanum praeruptorum Dunn. It is widely utilized for treating wind-heat colds and coughs accompanied by excessive phlegm. However, due to morphological similarities, limited resources, and heightened market demand, numerous substitutes and adulterants of Peucedani Radix have emerged within the herbal medicine market. Moreover, Peucedani Radix is typically dried and sliced for sale, rendering traditional identification methods challenging. MATERIALS AND METHODS: We initially examined and compared 104 commercial "Qian-hu" samples from various Chinese medicinal markets and 44 species representing genuine, adulterants or substitutes, utilizing the mini barcode ITS2 region to elucidate the botanical origins of the commercial "Qian-hu". The nucleotide signature specific to Peucedani Radix was subsequently developed by analyzing the polymorphic sites within the aligned ITS2 sequences. RESULTS: The results demonstrated a success rate of 100% and 93.3% for DNA extraction and PCR amplification, respectively. Forty-five samples were authentic "Qian-hu", while the remaining samples were all adulterants, originating from nine distinct species. Peucedani Radix, its substitutes, and adulterants were successfully identified based on the neighbor-joining tree. The 24-bp nucleotide signature (5'-ATTGTCGTACGAATCCTCGTCGTC-3') revealed distinct differences between Peucedani Radix and its common substitutes and adulterants. The newly designed specific primers (PR-F/PR-R) can amplify the nucleotide signature region from commercial samples and processed materials with severe DNA degradation. CONCLUSIONS: We advocate for the utilization of ITS2 and nucleotide signature for the rapid and precise identification of herbal medicines and their adulterants to regulate the Chinese herbal medicine industry.


Subject(s)
DNA Barcoding, Taxonomic , DNA, Plant , DNA, Plant/genetics , DNA Barcoding, Taxonomic/methods , Drugs, Chinese Herbal/standards , Apiaceae/genetics , Apiaceae/classification , Medicine, Chinese Traditional/standards , DNA, Ribosomal Spacer/genetics , Drug Contamination , Plants, Medicinal/genetics , Phylogeny , Sequence Analysis, DNA/methods , Polymerase Chain Reaction/methods , Nucleotides/genetics , Nucleotides/analysis
16.
Appl Microbiol Biotechnol ; 108(1): 376, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38884656

ABSTRACT

Mushroom poisoning contributes significantly to global foodborne diseases and related fatalities. Amanita mushrooms frequently cause such poisonings; however, identifying these toxic species is challenging due to the unavailability of fresh and intact samples. It is often necessary to analyze residues, vomitus, or stomach extracts to obtain DNA sequences for the identification of species responsible for causing food poisoning. This usually proves challenging to obtain usable DNA sequences that can be analyzed using conventional molecular biology techniques. Therefore, this study aimed to develop a DNA mini-barcoding method for the identification of Amanita species. Following the evaluation and optimization of universal primers for DNA mini-barcoding in Amanita mushrooms, we found that the internal transcribed spacer (ITS) gene sequence primer ITS-a was the most suitable DNA barcode primer for identifying Amanita species. Forty-three Amanita samples were subsequently amplified and sequenced. The sequences obtained were analyzed for intra- and inter-species genetic distances, and a phylogenetic tree was constructed. The findings indicated that the designed primers had strong universality among the Amanita samples and could accurately identify the target gene fragment with a length of 290 bp. Notably, the DNA mini-barcode accurately identified the 43 Amanita samples, demonstrating high consistency with the conventional DNA barcode. Furthermore, it effectively identified DNA from digested samples. In summary, this DNA mini-barcode is a promising tool for detecting accidental ingestion of toxic Amanita mushrooms. It may be used as an optimal barcode for species identification and traceability in events of Amanita-induced mushroom poisoning. KEY POINTS: • Development of a DNA mini-barcoding method for Amanita species identification without fresh samples. • The ITS-a primer set was optimized for robust universality in Amanita samples. • The mini-barcode is suitable for screening toxic mushroom species in mushroom poisoning cases.


Subject(s)
Amanita , DNA Barcoding, Taxonomic , DNA, Fungal , Mushroom Poisoning , Phylogeny , Mushroom Poisoning/diagnosis , Amanita/genetics , DNA, Fungal/genetics , DNA Primers/genetics , DNA, Ribosomal Spacer/genetics , Sequence Analysis, DNA , Humans
17.
Antonie Van Leeuwenhoek ; 117(1): 43, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38413427

ABSTRACT

As part of a long-term study aiming to isolate and identify yeast species that inhabit the surface of leaves and fruits of native fine-aroma cacao in the department of Amazonas, Peru, we obtained multiple isolates of Hannaella species. Yeasts of the genus Hannaella are common inhabitants of the phyllosphere of natural and crop plants. On the basis of morphological, and physiological characteristics, and sequence analysis of the D1/D2 domains of the large subunit rRNA gene (LSU) and the internal transcribed spacer region (ITS), we identified five species of Hannaella from the phyllosphere of Peruvian cacao. Four have been previously described: H. phyllophila (isolates KLG-073, KLG-091), H. pagnoccae (KLG-076), H. sinensis (KLG-121), and H. taiwanensis (KLG-021). A fifth, represented by eight isolates (KLG-034, KLG-063, KLG-074, KLG-078, KLG-79, KLG-082, KLG-084, KLG-085), is not conspecific with any previously described Hannaella species, and forms the sister clade to H. surugaensis in the phylogenetic analysis. It has 2.6-3.9% (18-27 substitutions, 2-4 deletions, and 1-3 insertions in 610-938 bp-long alignments), and 9.8-10.0% nucleotide differences (37 substitutions and 14 insertions in 511-520 bp-long alignments) in the LSU and ITS regions, respectively, to H. surugaensis type strain, CBS 9426. Herein, the new species Hannaella theobromatis sp. nov. is described and characterised. The species epithet refers to its epiphytic ecology on its host Theobroma cacao.


Subject(s)
Basidiomycota , Cacao , Cacao/genetics , Phylogeny , Peru , DNA, Ribosomal Spacer/genetics , Fruit , Plant Leaves , Basidiomycota/genetics , DNA, Fungal/genetics , Sequence Analysis, DNA , Mycological Typing Techniques , Thailand
18.
Antonie Van Leeuwenhoek ; 117(1): 77, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38717550

ABSTRACT

The "Shadegan International Wetland" (SIW) is one of the wetlands internationally recognized in the Ramsar convention. The vegetation of this wetland ecosystem consists of mostly grasses and shrubs that host a large number of fungi including endophytes. In this study, Nigrospora isolates were obtained from healthy plants of this wetland and its surrounding salt marshes and identified based on morphological features and multilocus phylogenetic analyses based on three DNA loci, namely the internal transcribed spacer regions 1 and 2 including the intervening 5.8S nuclear ribosomal DNA (ITS), ß-tubulin (tub2), and elongation factor 1-α (tef1-α). Accordingly, the following Nigrospora species were identified: N. lacticolonia, N. oryzae, N. osmanthi, N. pernambucoensis and a novel taxon N. shadeganensis sp. nov., which is described and illustrated. To the best of our knowledge, 10 new hosts for Nigrospora species are here reported, namely Aeluropus lagopoides, Allenrolfea occidentalis, Anthoxanthum monticola, Arthrocnemum macrostachyum, Cressa cretica, Halocnemum strobilaceum, Seidlitzia rosmarinus, Suaeda vermiculata, Tamarix passerinoides, and Typha latifolia. Moreover, the species N. lacticolonia and N. pernambucoensis are new records for the mycobiota of Iran.


Subject(s)
Ascomycota , Endophytes , Phylogeny , Poaceae , Wetlands , Iran , Endophytes/classification , Endophytes/genetics , Endophytes/isolation & purification , Poaceae/microbiology , Ascomycota/genetics , Ascomycota/classification , Ascomycota/isolation & purification , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Tubulin/genetics
19.
Phytopathology ; 114(5): 955-960, 2024 May.
Article in English | MEDLINE | ID: mdl-38349782

ABSTRACT

Red leaf blotch of soybean, caused by the fungus Coniothyrium glycines, is a foliar disease characterized by blotching, necrosis, and defoliation that has only been reported from Africa. The species is listed as a Select Agent by the Federal Select Agent Program due to its potentially devastating impacts to soybean production should it spread to the United States. Despite its potential import, very few isolates are available for study. Herein, we obtained 96 new C. glycines isolates from six soybean-producing countries throughout sub-Saharan Africa. Along with 12 previously collected ones, we sequenced each at the internal transcribed spacer (ITS) region. Between all isolates, we identified a total of 28 single-nucleotide polymorphisms and 23 haplotypes. One hypothesis to explain the tremendous diversity uncovered at the ITS-which is generally conserved within a species-is that our current species concept of C. glycines is too broad and that there may be multiple species that cause red leaf blotch. Zambia contained the highest haplotype diversity, a significant fraction of which remains unsampled. Most haplotypes were specific to a single country, except for two, which were found in Zambia and either neighboring Mozambique or Zimbabwe. This geographic specificity indicates that the ITS region may be useful for identifying source populations or routes of transmission should this pathogen spread beyond Africa. The observed geographic partitioning of this pathogen is likely the result of millions of years of replication on little-studied native hosts, given that soybean has only been cultivated in Africa since the early 1900s.


Subject(s)
Ascomycota , Glycine max , Haplotypes , Plant Diseases , Plant Diseases/microbiology , Ascomycota/genetics , Africa South of the Sahara , Glycine max/microbiology , Genetic Variation , Phylogeny , Polymorphism, Single Nucleotide/genetics , DNA, Ribosomal Spacer/genetics , DNA, Fungal/genetics , Sequence Analysis, DNA , Plant Leaves/microbiology
20.
Med Vet Entomol ; 38(2): 216-226, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38563591

ABSTRACT

Vector control remains one of the best strategies to prevent the transmission of trypanosome infections in humans and livestock and, thus, a good way to achieve the elimination of human African trypanosomiasis and animal African trypanosomiasis. A key prerequisite for the success of any vector control strategy is the accurate identification and correct mapping of tsetse species. In this work, we updated the tsetse fly species identification and distribution in many geographical areas in Cameroon. Tsetse flies were captured from six localities in Cameroon, and their species were morphologically identified. Thereafter, DNA was extracted from legs of each tsetse fly and the length polymorphism of internal transcribed spacer-1 (ITS1) region of each fly was investigated using PCR. ITS1 DNA fragments of each tsetse species were sequenced. The sequences obtained were analysed and compared to those available in GenBank. This enabled to confirm/infirm results of the morphologic identification and then, to establish the phylogenetic relationships between tsetse species. Morphologic features allowed to clearly distinguish all the tsetse species captured in the South Region of Cameroon, that is, Glossina palpalis palpalis, G. pallicera, G. caliginea and G. nigrofusca. In the northern area, G. morsitans submorsitans could also be distinguished from G. palpalis palpalis, G. tachinoides and G. fuscipes, but these three later could not be distinguished with routine morphological characters. The ITS1 length polymorphism was high among most of the studied species and allowed to identify the following similar species with a single PCR, that is, G. palpalis palpalis with 241 or 242 bp and G. tachinoides with 221 or 222 bp, G. fuscipes with 236 or 237 bp. We also updated the old distribution of tsetse species in the areas assessed, highlighting the presence of G. palpalis palpalis instead of G. fuscipes in Mbakaou, or in sympatry with G. morsitans submorsitans in Dodeo (northern Cameroon). This study confirms the presence of G. palpalis palpalis in the Adamawa Region of Cameroon. It highlights the limits of using morphological criteria to differentiate some tsetse species. Molecular tools based on the polymorphism of ITS1 of tsetse flies can differentiate tsetse species through a simple PCR before downstream analyses or vector control planning.


Subject(s)
Insect Vectors , Polymorphism, Genetic , Tsetse Flies , Animals , Cameroon , Tsetse Flies/genetics , Insect Vectors/genetics , Insect Vectors/classification , Animal Distribution , Phylogeny , DNA, Intergenic/genetics , Female , Insect Control , Male , DNA, Ribosomal Spacer/analysis , DNA, Ribosomal Spacer/genetics , Sequence Analysis, DNA
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