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1.
Artículo en Inglés | MEDLINE | ID: mdl-38359091

RESUMEN

A novel filamentous actinobacterium designated strain 4-36T showing broad-spectrum antifungal activity was isolated from a coal mining site in Mongolia, and its taxonomic position was determined using polyphasic approach. Optimum growth occurred at 30 °C, pH 7.5 and in the absence of NaCl. Aerial and substrate mycelia were abundantly formed on agar media. The colour of aerial mycelium was white and diffusible pigments were not formed. Phylogenetic analyses based on 16S rRNA gene sequence showed that strain 4-36T formed a distinct clade within the genus Amycolatopsis. The 16S rRNA gene sequence similarity showed that the strain was mostly related to Amycolatopsis lexingtonensis DSM 44544T and Amycolatopsis rifamycinica DSM 46095T with 99.3 % sequence similarity. However, the highest digital DNA-DNA hybridization value to closest species was 44.1 %, and the highest average nucleotide identity value was 90.2 %, both of which were well below the species delineation thresholds. Chemotaxonomic properties were typical of the genus Amycolatopsis, as the major fatty acids were C15 : 0, iso-C16 : 0 and C16 : 0, the cell-wall diamino acid was meso-diaminopimelic acid, the quinone was MK-9(H4), and the main polar lipids were diphosphatidylglycerol, phosphatidylmethanolamine and phosphatidylethanolamine. The in silico prediction of chemotaxonomic markers was also carried out by phylogenetic analysis. The genome mining for biosynthetic gene clusters of secondary metabolites in strain 4-36T revealed the presence of 34 gene clusters involved in the production of polyketide synthase, nonribosomal peptide synthetase, ribosomally synthesized and post-translationally modified peptide, lanthipeptide, terpenes, siderophore and many other unknown clusters. Strain 4-36T showed broad antifungal activity against several filamentous fungi. The phenotypic, biochemical and chemotaxonomic properties indicated that the strain could be clearly distinguished from other species of Amycolatopsis, and thus the name Amycolatopsis mongoliensis sp. nov. is proposed accordingly (type strain, 4-36T=KCTC 39526T=JCM 30565T).


Asunto(s)
Actinomycetales , Minas de Carbón , Ácidos Grasos/química , Amycolatopsis , Antifúngicos/farmacología , Filogenia , ARN Ribosómico 16S/genética , Mongolia , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Composición de Base , Análisis de Secuencia de ADN , Fosfolípidos/química
2.
Artículo en Inglés | MEDLINE | ID: mdl-37000168

RESUMEN

A novel Gram-stain-negative, aerobic, rod-shaped, non-motile, cream-coloured strain (G124T) was isolated from ginseng soil collected in Yeongju, Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain G124T belongs to a distinct lineage within the genus Sphingomonas (family Sphingomonadaceae, order Sphingomonadales and class Alphaproteobacteria). Strain G124T was closely related to Sphingomonas rhizophila THG-T61T (98.5 % 16S rRNA gene sequence similarity), Sphingomonas mesophila SYSUP0001T (98.3 %), Sphingomonas edaphi DAC4T (97.6 %) and Sphingomonas jaspsi TDMA-16T (97.6 %). The strain contained ubiquinone 10 as the major respiratory quinone. The major polar lipid profile of strain G124T comprised phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine and sphingoglycolipids. The predominant cellular fatty acids of strain G124T were summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c; 33.4 %), summed feature 3 (C16 : 1 ω6c/C16 : 1 ω7c; 27.2 %) and C16 : 0 (18.3 %). The genome size of strain G124T was 2 549 305 bp. The genomic DNA G+C content is 62.0 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain G124T and other Sphingomonas species were in the range of 71.2-75.9 % and 18.7-19.9 %, respectively. Based on the polyphasic analysis such as biochemical, phylogenetic and chemotaxonomic characteristics, strain G124T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas cremea sp. nov. is proposed. The type strain is G124T (=KACC 21691T=LMG 31729T).


Asunto(s)
Panax , Sphingomonas , Ácidos Grasos/química , Fosfolípidos/química , Filogenia , ARN Ribosómico 16S/genética , Espermidina/química , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN
3.
FASEB J ; 35(4): e21479, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33710680

RESUMEN

Triggering receptor expressed on myeloid cells 2 (TREM2) is a cell surface receptor expressed on macrophages, microglial cells, and pre-osteoclasts, and that participates in diverse cellular function, including inflammation, bone homeostasis, neurological development, and coagulation. In spite of the indispensable role of the TREM2 protein in the maintenance of immune homeostasis and osteoclast differentiation, the exact ligand for TREM2 has not yet been identified. Here, we report a putative TREM2 ligand which is secreted from MC38 cells and identified as a cyclophilin A (CypA). A specific interaction between CypA and TREM2 was shown at both protein and cellular levels. Exogenous CypA specifically interacted and co-localized with TREM2 in RAW264.7 cells, and the physical interactions were shown to regulate TREM2 signaling transduction. The Pro144 residue in the extracellular domain of TREM2 was found to be the specific binding site of CypA. When considered together, this provides evidence that CypA interacts specifically with TREM2 as a potent ligand.


Asunto(s)
Ciclofilina A/metabolismo , Ligandos , Microglía/metabolismo , Células Mieloides/metabolismo , Animales , Proteínas Portadoras/metabolismo , Células Cultivadas , Humanos , Macrófagos/metabolismo , Osteoclastos/metabolismo
4.
Arch Microbiol ; 204(12): 697, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36352163

RESUMEN

Two novel bacterial strains BT178T and BT635T were isolated from soil collected in Gyeonggi province, Republic of Korea. Both strains were Gram-negative, rod-shaped circular, and had convex, glistening, pink-colored colonies. Phylogenetic analysis based on 16S rRNA gene sequences showed that each of the strains BT178T and BT635T formed an individual lineage within the genus Hymenobacter (family Hymenobacteraceae, order Cytophagales, class Cytophagia, phylum Bacteroidetes). The 16S rRNA gene sequence similarity between the two strains BT178T and BT635T were 97.7%. Both strains had Q-7 as the major respiratory quinone and phosphatidylethanolamine (PE) as the major polar lipids. The main cellular fatty acids of strain BT178T were iso-C15:0, anteiso-C15:0, and those of strain BT635T were iso-C15:0 and Summed Feature 4 (iso-C17:1 I / anteiso-C17:1 B). Based on the result of polyphasic taxonomic analysis, two novel species, Hymenobacter lucidus BT178T (= KCTC 72333T = NBRC 115442T) and Hymenobacter nitidus BT635T (= KACC 21904T = NBRC 115443T) were proposed.


Asunto(s)
Cytophagaceae , Suelo , ARN Ribosómico 16S/genética , Filogenia , Composición de Base , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Bacteroidetes , Microbiología del Suelo , Ácidos Grasos/análisis
5.
Fungal Divers ; 109(1): 59-98, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34608378

RESUMEN

The increasing number of new fungal species described from all over the world along with the use of genetics to define taxa, has dramatically changed the classification system of early-diverging fungi over the past several decades. The number of phyla established for non-Dikarya fungi has increased from 2 to 17. However, to date, both the classification and phylogeny of the basal fungi are still unresolved. In this article, we review the recent taxonomy of the basal fungi and re-evaluate the relationships among early-diverging lineages of fungal phyla. We also provide information on the ecology and distribution in Mucoromycota and highlight the impact of chytrids on amphibian populations. Species concepts in Chytridiomycota, Aphelidiomycota, Rozellomycota, Neocallimastigomycota are discussed in this paper. To preserve the current application of the genus Nephridiophaga (Chytridiomycota: Nephridiophagales), a new type species, Nephridiophaga blattellae, is proposed.

6.
Fungal Divers ; 111(1): 1-335, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34899100

RESUMEN

This article is the 13th contribution in the Fungal Diversity Notes series, wherein 125 taxa from four phyla, ten classes, 31 orders, 69 families, 92 genera and three genera incertae sedis are treated, demonstrating worldwide and geographic distribution. Fungal taxa described and illustrated in the present study include three new genera, 69 new species, one new combination, one reference specimen and 51 new records on new hosts and new geographical distributions. Three new genera, Cylindrotorula (Torulaceae), Scolecoleotia (Leotiales genus incertae sedis) and Xenovaginatispora (Lindomycetaceae) are introduced based on distinct phylogenetic lineages and unique morphologies. Newly described species are Aspergillus lannaensis, Cercophora dulciaquae, Cladophialophora aquatica, Coprinellus punjabensis, Cortinarius alutarius, C. mammillatus, C. quercoflocculosus, Coryneum fagi, Cruentomycena uttarakhandina, Cryptocoryneum rosae, Cyathus uniperidiolus, Cylindrotorula indica, Diaporthe chamaeropicola, Didymella azollae, Diplodia alanphillipsii, Dothiora coronicola, Efibula rodriguezarmasiae, Erysiphe salicicola, Fusarium queenslandicum, Geastrum gorgonicum, G. hansagiense, Helicosporium sexualis, Helminthosporium chiangraiensis, Hongkongmyces kokensis, Hydrophilomyces hydraenae, Hygrocybe boertmannii, Hyphoderma australosetigerum, Hyphodontia yunnanensis, Khaleijomyces umikazeana, Laboulbenia divisa, Laboulbenia triarthronis, Laccaria populina, Lactarius pallidozonarius, Lepidosphaeria strobelii, Longipedicellata megafusiformis, Lophiotrema lincangensis, Marasmius benghalensis, M. jinfoshanensis, M. subtropicus, Mariannaea camelliae, Melanographium smilaxii, Microbotryum polycnemoides, Mimeomyces digitatus, Minutisphaera thailandensis, Mortierella solitaria, Mucor harpali, Nigrograna jinghongensis, Odontia huanrenensis, O. parvispina, Paraconiothyrium ajrekarii, Parafuscosporella niloticus, Phaeocytostroma yomensis, Phaeoisaria synnematicus, Phanerochaete hainanensis, Pleopunctum thailandicum, Pleurotheciella dimorphospora, Pseudochaetosphaeronema chiangraiense, Pseudodactylaria albicolonia, Rhexoacrodictys nigrospora, Russula paravioleipes, Scolecoleotia eriocamporesi, Seriascoma honghense, Synandromyces makranczyi, Thyridaria aureobrunnea, Torula lancangjiangensis, Tubeufia longihelicospora, Wicklowia fusiformispora, Xenovaginatispora phichaiensis and Xylaria apiospora. One new combination, Pseudobactrodesmium stilboideus is proposed. A reference specimen of Comoclathris permunda is designated. New host or distribution records are provided for Acrocalymma fici, Aliquandostipite khaoyaiensis, Camarosporidiella laburni, Canalisporium caribense, Chaetoscutula juniperi, Chlorophyllum demangei, C. globosum, C. hortense, Cladophialophora abundans, Dendryphion hydei, Diaporthe foeniculina, D. pseudophoenicicola, D. pyracanthae, Dictyosporium pandanicola, Dyfrolomyces distoseptatus, Ernakulamia tanakae, Eutypa flavovirens, E. lata, Favolus septatus, Fusarium atrovinosum, F. clavum, Helicosporium luteosporum, Hermatomyces nabanheensis, Hermatomyces sphaericoides, Longipedicellata aquatica, Lophiostoma caudata, L. clematidis-vitalbae, Lophiotrema hydei, L. neoarundinaria, Marasmiellus palmivorus, Megacapitula villosa, Micropsalliota globocystis, M. gracilis, Montagnula thailandica, Neohelicosporium irregulare, N. parisporum, Paradictyoarthrinium diffractum, Phaeoisaria aquatica, Poaceascoma taiwanense, Saproamanita manicata, Spegazzinia camelliae, Submersispora variabilis, Thyronectria caudata, T. mackenziei, Tubeufia chiangmaiensis, T. roseohelicospora, Vaginatispora nypae, Wicklowia submersa, Xanthagaricus necopinatus and Xylaria haemorrhoidalis. The data presented herein are based on morphological examination of fresh specimens, coupled with analysis of phylogenetic sequence data to better integrate taxa into appropriate taxonomic ranks and infer their evolutionary relationships.

7.
Nucleic Acids Res ; 46(15): e92, 2018 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-29873758

RESUMEN

Calling variants from next-generation sequencing (NGS) data or discovering discordant sequences between two NGS data sets is challenging. We developed a computer algorithm, ADIScan1, to call variants by comparing the fractions of allelic reads in a tester to the universal reference genome. We then created ADIScan2 by modifying the algorithm to directly compare two sets of NGS data and predict discordant sequences between two testers. ADIScan1 detected >99.7% of variants called by GATK with an additional 724 393 SNVs. ADIScan2 identified ∼500 candidates of discordant sequences in each of two pairs of the monozygotic twins. About 200 of these candidates were included in the ∼2800 predicted by VarScan2. We verified 66 true discordant sequences among the candidates that ADIScan2 and VarScan2 exclusively predicted. ADIScan2 detected many discordant sequences overlooked by VarScan2 and Mutect, which specialize in detecting low frequency mutations in genetically heterogeneous cancerous tissues. Numbers of verified sequences alone were >5 times more than expected based on recently estimated mutation rates from whole genome sequences. Estimated post-zygotic mutation rates were 1.68 × 10-7 in this study. ADIScan1 and 2 would complement existing tools in screening causative mutations of diverse genetic diseases and comparing two sets of genome sequences, respectively.


Asunto(s)
Algoritmos , Biología Computacional/métodos , Variaciones en el Número de Copia de ADN , Polimorfismo de Nucleótido Simple , Gemelos Monocigóticos/genética , Genoma Humano/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Mutación , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN/métodos , Secuenciación Completa del Genoma/métodos
8.
Plant Dis ; 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32931386

RESUMEN

Vicia sativa subsp. nigra, also known as narrow-leaved vetch, belongs to the family Fabaceae and is distributed in different countries.Vetch is one of the most important annual forage legumes in the world; it is used as hay, grain, silage, green manure, and livestock fodder. In Korea, this plant is often used as cattle feed. In early May of 2019 and 2020, a powdery mildew was observed on leaves of V. sativa subsp. nigra plants in a garden of Chonnam National University, Gwangju, Korea. The first symptom appeared on the upper surface of the leaves as a small white spot. Within two weeks, the white spots of powdery mildew spread and covered the entire leaf. Voucher specimens were deposited at the Environmental Microbiology Laboratory Herbarium, Chonnam National University, Gwangju, Korea, under the accession numbers CNUFC PWV1 and CNUFC PWV2. The hyphal appressoria of the fungus were nipple-shaped, moderately lobed or multilobed, single or in opposite pairs. Measurements were made of 35 conidiophores and 55 conidia. Conidiophores arising from the upper part of mother cells, were cylindrical, 60.5 to 117.5 × 7.5 to 9.5 µm. The foot cells of the conidiophores were cylindrical, straight to slightly curved at the base, 23.5 to 38.7 × 7.3 to 9.2 µm, followed by 2-3 shorter cells. Conidia were formed singly, subcylindrical to oval, 32.5 to 48.7 × 13.5 to 19.7 µm. Conidia produced short to long germ tubes, terminating in lobed or unlobed appressoria. No chasmothecia were observed. The morphological characteristics of conidiophores and conidia were consistent with the description of Erysiphe viciae-unijugae in Shin (2000). However, it was not possible to identify the fungus only based on the asexual morph. In addition, the conidiophore and conidium shapes of E. baeumleri on the known host V. sativa were similar to those of E. viciae-unijugae (Braun and Cook 2012). Therefore, genomic DNA was extracted directly from the mycelia and conidia using a DNA prep kit (Solgent, Daejeon, Korea). The internal transcribed spacer (ITS) regions ofribosomal DNA (rDNA) and 28S rDNA from the two specimens were amplified using the primers ITS5 and PM6 (Takamatsu and Kano 2001), and LROR and LR3 (Vilgalys and Hester 1990), respectively. A BLASTn search with the ITS sequences indicated that CNUFC PWV1 (GenBank accession no. MT509395) and CNUFC PWV2 (MT509396) were 100% (503/503 bp) and 99.8% (502/503 bp) identical to those of E. viciae-unijugae (LC010086 and LC009962), respectively. The 28S sequences of CNUFC PWV1 (MT705629) and CNUFC PWV2 (MT705630) showed 99.8% (507/508 bp) and 99.4% (505/508 bp) identity values with E. viciae-unijugae (LC009976 and LC010029), respectively. Phylogenetic analyses based on the combined ITS and 28S rDNA sequences indicated that the two specimens, CNUFC PWV1 and CNUFC PWV2, formed a monophyletic clade together with sequences retrieved from E. viciae-unijugae. Therefore, the causal pathogen was identified as E. viciae-unijugae based on the results of morphological and molecular analyses. Pathogenicity tests were performed by gently pressing the infected leaves onto 10 young leaves of three healthy plants. A non-inoculated plant was used as a control. The plants were maintained in a greenhouse at 22 to 25°C, with relative humidity around 75%, and natural light. Powdery mildew symptoms were observed on the inoculated leaves after 10-14 days, whereas no symptoms were observed on the leaves of the control. The fungi on the inoculated leaves were morphologically identical to the fungi on the original infected leaves. Erysiphe viciae-unijugae has been reported to occur on Lathyrus spp. and Vicia spp. (Farr and Rossman 2020). To our knowledge, this is the first report of powdery mildew caused by E. viciae-unijugae on V. sativa subsp. nigra in Korea. The weather conditions, especially during May, are favorable for disease outbreaks. This disease may be a potential threat to feed production in Korea.

9.
Int J Syst Evol Microbiol ; 67(9): 3387-3392, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28857027

RESUMEN

Little is known on members of the genus Amycolatopsis inhabiting acidic habitats. In this study, a moderately acidophilic Amycolatopsis strain, designated 2-5T, was isolated from coal mine soil, and subjected to a polyphasic taxonomic characterization. Analysis based on 16S rRNA gene sequences indicated that the strain was most closely related to the type strain of Amycolatopsis bartoniae, sharing 99.30 % similarity, while similarity to all other Amycolatopsis species was less than 97 %. The DNA-DNA relatedness between the new isolate and the type strain of A. bartoniae was 56.5±0.7 %. The optimal pH range of the isolate for growth was 5.5-6.0, but growth also occurred at pH 4.5 and 7.5. The isolate tolerated up to 6 % (w/v) NaCl (optimum, 0 %), and the temperature range for growth was 15-40 °C (optimum, 30 °C). The isolate was able to utilize most substrates tested for sole carbon sources, showing its metabolic versatility. The isolate exhibited antimicrobial activity against Serratia marcescens and weak antifungal activity against Fusarium proliferatum. The chemotaxonomic profiles of strain 2-5T included polar lipids containing phosphatidylethanolamine, phsphatidylmethylethanolamine, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol dimannosides, fatty acids containing C17 : 1ω6c and iso-C16 : 0 as the major components, MK-9(H4) as the predominant menaquinone, and meso-diaminopimelic acid and arabinose, galactose, glucose and ribose as the diagnostic diamino acid and sugars in the cell wall. The combined phenotypic, chemotaxonomic and genotypic analyses clearly indicated that the isolate merits recognition as represnting a novel species of Amycolatopsis, for which the name Amycolatopsis acidiphila sp. nov. is proposed. The type strain is 2-5T (=KCTC 39523T=JCM 30562T).


Asunto(s)
Actinomycetales/clasificación , Minas de Carbón , Filogenia , Microbiología del Suelo , Actinomycetales/genética , Actinomycetales/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , Pared Celular/química , ADN Bacteriano/genética , ADN Ribosómico/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Mongolia , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
10.
Int J Mol Sci ; 15(9): 15272-86, 2014 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-25170812

RESUMEN

Chinese boxthorn or matrimony vine (Lycium chinense Mill) is found primarily in southeastern Europe and Asia, including Korea. The dried ripe fruits are commonly used as oriental medicinal purposes. Endophytic fungi were isolated from surface sterilized tissues and fruits of the medicinal plant in 2013 to identify the new or unreported species in Korea. Among 14 isolates, 10 morphospecies were selected for molecular identification with the internal transcribed spacer (ITS) gene. Phylogenetic analysis revealed that all isolates belonged to Ascomycota including the genera Acremonium, Colletotrichum, Cochliobolus, Fusarium, Hypocrea and Nemania. Two Colletotrichum species were identified at the species level, using three genes including internal transcribed spacer (ITS), glycerol-3-phosphate dehydrogenase (GAPDH) and Actin (ACT) for PCR and molecular data analysis along with morphological observations. The fungal isolates, CNU122031 and CNU122032 were identified as Colletotrichum fructicola and C. brevisporum, respectively. Morphological observations also well supported the molecular identification. C. brevisporum is represented unrecorded species in Korea and C. fructicola is the first record from the host plant.


Asunto(s)
Colletotrichum/genética , Lycium/microbiología , Filogenia , Actinas/genética , Colletotrichum/clasificación , Colletotrichum/aislamiento & purificación , ADN Intergénico/genética , Proteínas Fúngicas/genética , Gliceraldehído-3-Fosfato Deshidrogenasa (Fosforilante)/genética
11.
Molecules ; 19(8): 10717-32, 2014 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-25061722

RESUMEN

Brassica species produce the antifungal indolyl compounds brassinin and its derivatives, during microbial infection. The fungal pathogen Alternaria brassicicola detoxifies brassinin and possibly its derivatives. This ability is an important property for the successful infection of brassicaceous plants. Previously, we identified a transcription factor, Bdtf1, essential for the detoxification of brassinin and full virulence. To discover genes that encode putative brassinin-digesting enzymes, we compared gene expression profiles between a mutant strain of the transcription factor and wild-type A. brassicicola under two different experimental conditions. A total of 170 and 388 genes were expressed at higher levels in the mutants than the wild type during the infection of host plants and saprophytic growth in the presence of brassinin, respectively. In contrast, 93 and 560 genes were expressed, respectively, at lower levels in the mutant than the wild type under the two conditions. Fifteen of these genes were expressed at lower levels in the mutant than in the wild type under both conditions. These genes were assumed to be important for the detoxification of brassinin and included Bdtf1 and 10 putative enzymes. This list of genes provides a resource for the discovery of enzyme-coding genes important in the chemical modification of brassinin.


Asunto(s)
Alternaria/efectos de los fármacos , Alternaria/genética , Eliminación de Gen , Regulación Fúngica de la Expresión Génica , Indoles/farmacología , Sesquiterpenos/farmacología , Tiocarbamatos/farmacología , Transcripción Genética/efectos de los fármacos , Brassica/metabolismo , Brassica/microbiología , Análisis por Conglomerados , Perfilación de la Expresión Génica , Interacciones Huésped-Patógeno , Fitoalexinas
12.
mBio ; : e0014424, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38953355

RESUMEN

Dimorphism is known among the etiologic agents of endemic mycoses as well as in filamentous Mucorales. Under appropriate thermal conditions, mononuclear yeast forms alternate with multi-nucleate hyphae. Here, we describe a dimorphic mucoralean fungus obtained from the sputum of a patient with Burkitt lymphoma and ongoing graft-versus-host reactions. The fungus is described as Mucor germinans sp. nov. Laboratory studies were performed to simulate temperature-dependent dimorphism, with two environmental strains Mucor circinelloides and Mucor kunryangriensis as controls. Both strains could be induced to form multinucleate arthrospores and subsequent yeast-like cells in vitro. Multilateral yeast cells emerge in all three Mucor species at elevated temperatures. This morphological transformation appears to occur at body temperature since the yeast-like cells were observed in the lungs of our immunocompromised patient. The microscopic appearance of the yeast-like cells in the clinical samples is easily confused with that of Paracoccidioides. The ecological role of yeast forms in Mucorales is discussed.IMPORTANCEMucormycosis is a devastating disease with high morbidity and mortality in susceptible patients. Accurate diagnosis is required for timely clinical management since antifungal susceptibility differs between species. Irregular hyphal elements are usually taken as the hallmark of mucormycosis, but here, we show that some species may also produce yeast-like cells, potentially being mistaken for Candida or Paracoccidioides. We demonstrate that the dimorphic transition is common in Mucor species and can be driven by many factors. The multi-nucleate yeast-like cells provide an effective parameter to distinguish mucoralean infections from similar yeast-like species in clinical samples.

13.
Microb Pathog ; 56: 8-15, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23333407

RESUMEN

The antifungal activities of methanolic extracts from Terminalia nigrovenulosa bark (TNB) was investigated for effects on the initial growth of mycelia against Fusarium solani. The ethyl acetate fraction separated from TNB demonstrated the highest antifungal activity against F. solani. The antifungal compound was isolated from TNB using silica gel column and Sephadex LH-20 chromatography combined with thin-layer chromatography and high performance liquid chromatography. Structural identification of the antifungal compound was conducted using (1)H NMR, (13)C NMR, and liquid chromatography-tandem mass spectrometry. The purified antifungal compound was gallic acid (GA) or 3,4,5-trihydroxy benzoic acid. Purified-GA possesses the high antifungal activity against F. solani, and that antifungal activity was dosage-dependent. The hyphae became collapsed and shrunken after 24 h incubation with GA (500 ppm). In pot experiments, the application of TNB crude extract was found to be effective in controlling the cucumber Fusarium root rot disease by enhancing activities of chitinase, peroxidase thereby promoting the growth of plants. The applied TNB extract significantly suppressed root rot disease compared to control. It resulted in 33, 75 and 81% disease suppression with 100, 500 and 1000 ppm of TNB crude extract, respectively. The study effectively demonstrated biological activities of the TNB extract, therefore suggesting the application of TNB for the control of soil-borne diseases of cucumber plants.


Asunto(s)
Antifúngicos/farmacología , Fusarium/efectos de los fármacos , Ácido Gálico/farmacología , Terminalia/química , Antifúngicos/aislamiento & purificación , Cromatografía , Cucumis sativus/microbiología , Relación Dosis-Respuesta a Droga , Fusarium/crecimiento & desarrollo , Ácido Gálico/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Micelio/efectos de los fármacos , Micelio/crecimiento & desarrollo , Corteza de la Planta/química , Enfermedades de las Plantas/microbiología , Raíces de Plantas/microbiología , Espectrometría de Masas en Tándem
14.
Biol Pharm Bull ; 36(11): 1747-53, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24189419

RESUMEN

The oral consumption of capsicum has been reported to increase interleukin (IL)-2 and interferon (IFN)-γ production in Peyer's patches (PP); however, the active components responsible for these effects have not been completely identified. The beneficial biological effects of green peppers cultivated under environmentally friendly farming conditions (ECP), without the use of chemical pesticides, have rarely been compared with those of green peppers cultivated under conventional farming conditions (CCP). Oral administration of ECP extract significantly induced the production of IL-2 and IFN-γ in concanavalin A-treated cells from PP ex vivo; their levels were much higher than those in the CCP extract-treated group. A comparative analysis of the HPLC profiles indicated a 1.7-fold increase of a peak, named EF-1, at 415 nm in the ECP extract. The major component of EF-1 was identified as pheophytin a, which is a chlorophyll a molecule lacking a central Mg(2+) ion, as determined from NMR data. Intake of pheophytin a and chlorophyll a significantly increased IL-2 and IFN-γ production, and the percentage of IL-2- and IFN-γ-producing CD4+ T-cells in PP. Taken together, our data suggest that ECPs produce a higher content of pheophytin a than CCPs, and pheophytin a and chlorophyll a are immune-modulating components in green vegetables.


Asunto(s)
Capsicum , Clorofila/farmacología , Interferón gamma/metabolismo , Interleucina-2/metabolismo , Ganglios Linfáticos Agregados/efectos de los fármacos , Feofitinas/farmacología , Agricultura/métodos , Animales , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/metabolismo , Células Cultivadas , Clorofila/aislamiento & purificación , Clorofila A , Masculino , Ratones , Ratones Endogámicos C57BL , Ganglios Linfáticos Agregados/metabolismo , Feofitinas/aislamiento & purificación , Extractos Vegetales/química
15.
Int J Mol Sci ; 14(2): 4349-60, 2013 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-23429275

RESUMEN

In an earlier study, we isolated potamin-1 (PT-1), a 5.6-kDa trypsin-chymotrypsin protease inhibitor, from the tubers of a potato strain (Solanum tuberosum L cv. Gogu Valley). We established that PT-1 strongly inhibits pathogenic microbial strains, but not human bacterial strains, and that its sequence shows 62% homology with a serine protease inhibitor. In the present study, we isolated an antifungal and antibacterial peptide with no cytotoxicity from tubers of the same potato strain. The peptide (peptide-G2, PG-2) was isolated using salt-extraction, ultrafiltration and reverse-phase high performance liquid chromatography (RP-HPLC). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) showed the protein to have a molecular mass of 3228.5 Da, while automated Edman degradation showed the N-terminal sequence of PG-2 to be LVKDNPLDISPKQVQALCTDLVIRCMCCC-. PG-2 exhibited antimicrobial activity against Candida albicans, a human pathogenic yeast strain, and Clavibacter michiganensis subsp. michiganensis, a plant late blight strain. PG-2 also showed antibacterial activity against Staphylococcus aureus, but did not lyse human red blood cells and was thermostable. Overall, these results suggest PG-2 may be a good candidate to serve as a natural antimicrobial agent, agricultural pesticide and/or food additive.

16.
Mycobiology ; 51(5): 320-332, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37929009

RESUMEN

Talaromyces is a genus within the phylum Ascomycota (class Eurotiomycetes, order Eurotiales, family Trichocomaceae). Many species in this genus are known to produce diverse secondary metabolites with great potential for agricultural, medical, and pharmaceutical applications. During a survey on fungal diversity in the genus Talaromyces in Korea, six strains were isolated from soil, indoor air, and freshwater environments. Based on morphological, physiological, and multi-locus (ITS, BenA, CaM, and RPB2) phylogenetic analyses, we identified five previously unrecorded species in Korea (T. brevis, T. fusiformis, T. muroii, T. ruber, and T. soli) and a new species (T. echinulatus sp. nov.) belonging to section Talaromyces. Herein, detailed descriptions, illustrations, and phylogenetic tree are provided.

17.
J Fungi (Basel) ; 9(3)2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36983485

RESUMEN

Species of Lichtheimia are important opportunistic fungal pathogens in the order Mucorales that are isolated from various sources such as soil, indoor air, food products, feces, and decaying vegetables. In recent years, species of Lichtheimia have become an emerging causative agent of invasive mucormycosis. In Europe and USA, Lichtheimia are the second and third most common causal fungus of mucormycosis, respectively. Thus, the aim of this study was to survey the diversity of species of Lichtheimia hidden in poorly studied hosts, such as invertebrates, in Korea. Eight Lichtheimia strains were isolated from invertebrate samples. Based on morphology, physiology, and phylogenetic analyses of ITS and LSU rDNA sequence data, the strains were identified as L. hyalospora, L. ornata, L. ramosa, and a novel species, L. koreana sp. nov. Lichtheimia koreana is characterized by a variable columellae, sporangiophores arising solitarily or up to three at one place from stolons, and slow growth on MEA and PDA at all temperatures tested. The new species grows best at 30 and 35 °C and has a maximum growth temperature of 40 °C. Detailed descriptions, illustrations, and a phylogenetic tree are provided.

18.
Mycobiology ; 51(6): 417-435, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38179116

RESUMEN

Eurotiales is a relatively large order of Ascomycetes, well-known for their ability to produce secondary metabolites with potential beneficial applications. To understand their diversity and distribution, different environmental sources including soil, freshwater, insect, and indoor air were investigated. Eight strains of Eurotiales were isolated and identified based on their morphological characters and a multi-gene phylogenetic analysis of the ITS, BenA, CaM, and RPB2 regions. We identified eight taxa that were previously not reported from Korea: Aspergillus baeticus, A. griseoaurantiacus, A. spinulosporus, Penicillium anthracinoglaciei, P. labradorum, P. nalgiovense, Talaromyces atroroseus, and T. georgiensis. Detailed descriptions, illustrations, and phylogenetic tree for the eight new records species are presented, and information regarding the records is also discussed.

19.
Sci Rep ; 13(1): 5371, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-37005456

RESUMEN

Axl is a tyrosine kinase receptor, a negative regulator for innate immune responses and inflammatory bowel disease (IBD). The gut microbiota regulates intestinal immune homeostasis, but the role of Axl in the pathogenesis of IBD through the regulation of gut microbiota composition remains unresolved. In this study, mice with DSS-induced colitis showed increased Axl expression, which was almost entirely suppressed by depleting the gut microbiota with antibiotics. Axl-/- mice without DSS administration exhibited increased bacterial loads, especially the Proteobacteria abundant in patients with IBD, significantly consistent with DSS-induced colitis mice. Axl-/- mice also had an inflammatory intestinal microenvironment with reduced antimicrobial peptides and overexpression of inflammatory cytokines. The onset of DSS-induced colitis occurred faster with an abnormal expansion of Proteobacteria in Axl-/- mice than in WT mice. These findings suggest that a lack of Axl signaling exacerbates colitis by inducing aberrant compositions of the gut microbiota in conjunction with an inflammatory gut microenvironment. In conclusion, the data demonstrated that Axl signaling could ameliorate the pathogenesis of colitis by preventing dysbiosis of gut microbiota. Therefore, Axl may act as a potential novel biomarker for IBD and can be a potential candidate for the prophylactic or therapeutic target of diverse microbiota dysbiosis-related diseases.


Asunto(s)
Colitis , Microbioma Gastrointestinal , Enfermedades Inflamatorias del Intestino , Microbiota , Ratones , Animales , Disbiosis/inducido químicamente , Enfermedades Inflamatorias del Intestino/microbiología , Proteobacteria , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Colon/microbiología
20.
J Fungi (Basel) ; 8(6)2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35736084

RESUMEN

Species in the genus Mucor have a worldwide distribution and are isolated from various substrata and hosts, including soil, dung, freshwater, and fruits. However, their diversity from insects is still much too little explored. The aim of this study was to characterize three new species of Mucor: Mucor grylli sp. nov., M. hyangburmii sp. nov., and M. kunryangriensis sp. nov., discovered in Kunryang-ri, Cheongyang in the Chungnam Province of Korea, during an investigation of Mucorales from cricket insects. The new species are described using morphological characters and molecular data including ITS and LSU rDNA regions. Mucor grylli is characterized by the highly variable shape of its columellae, which are subglobose to oblong, obovoid, strawberry-shaped, and sometimes slightly or strongly constricted in the center. Mucor hyangburmii is characterized by the production of azygospores and growth at 40 °C. Mucor kunryangriensis is characterized by the variable shape of its columellae, which are elongated-conical, obovoid, cylindrical ellipsoid, cylindrical, and production of abundant yeast-like cells on PDA, MEA, and SMA media. Based on the sequence analysis of two genetic markers, our phylogenic assessment strongly supported M. grylli, M. hyangburmii, and M. kunryangriensis as new species. Detailed descriptions, illustrations, and phylogenetic trees are provided.

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