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PloS One 2020Chromoblastomycosis (CBM) is a chronic subcutaneous mycosis caused by traumatic implantation of many species of black fungi. Due to the refractoriness of some cases and...
Chromoblastomycosis (CBM) is a chronic subcutaneous mycosis caused by traumatic implantation of many species of black fungi. Due to the refractoriness of some cases and common recurrence of CBM, a more effective and less time-consuming treatment is mandatory. The aim of this study was to identify compounds with in vitro antifungal activity in the Pathogen Box® compound collection against different CBM agents. Synergism of these compounds with drugs currently used to treat CBM was also assessed. An initial screening of the drugs present in this collection at 1 μM was performed with a Fonsecaea pedrosoi clinical strain according to the EUCAST protocol. The compounds with activity against this fungus were also tested against other seven etiologic agents of CBM (Cladophialophora carrionii, Phialophora verrucosa, Exophiala jeanselmei, Exophiala dermatitidis, Fonsecaea monophora, Fonsecaea nubica, and Rhinocladiella similis) at concentrations ranging from 0.039 to 10 μM. The analysis of potential synergism of these compounds with itraconazole and terbinafine was performed by the checkerboard method. Eight compounds inhibited more than 60% of the F. pedrosoi growth: difenoconazole, bitertanol, iodoquinol, azoxystrobin, MMV688179, MMV021013, trifloxystrobin, and auranofin. Iodoquinol produced the lowest MIC values (1.25-2.5 μM) and MMV688179 showed MICs that were higher than all compounds tested (5 - >10 μM). When auranofin and itraconazole were tested in combination, a synergistic interaction (FICI = 0.37) was observed against the C. carrionii isolate. Toxicity analysis revealed that MMV021013 showed high selectivity indices (SI ≥ 10) against the fungi tested. In summary, auranofin, iodoquinol, and MMV021013 were identified as promising compounds to be tested in CBM models of infection.
Topics: Acetates; Antifungal Agents; Ascomycota; Auranofin; Biphenyl Compounds; Chromoblastomycosis; Dioxolanes; Drug Synergism; Exophiala; Fungi; Humans; Imines; Iodoquinol; Pyrimidines; Strobilurins; Triazoles
PubMed: 32401759
DOI: 10.1371/journal.pone.0229630 -
Journal of Clinical Microbiology May 1995Because of their ability to display yeast-like growth forms in various environmental conditions, dematiaceous (melanized) hyphomycetes of the form-genera Exophiala,... (Comparative Study)
Comparative Study
Because of their ability to display yeast-like growth forms in various environmental conditions, dematiaceous (melanized) hyphomycetes of the form-genera Exophiala, Rhinocladiella, and Wangiella have been informally termed "black yeasts." Cladistic analysis of 1,050 bp of the genes coding for small-subunit rRNA (SSU rDNA) supported a close relationship among species of these black yeasts with other dematiaceous hyphomycetes in the form-genera Fonsecaea, Phialophora, and Ramichloridium. The conventional categories of these fungi based on asexual states are not supported by phylogenetic analysis of SSU rDNA sequences. Isolates exhibiting annellidic modes of blastic conidiogenesis (e.g., Exophiala spp.) were not monophyletic and were placed as sister taxa to isolates that produce phialides or sympodulae. The results indicated very close relationships between isolates of Wangiella dermatitidis and Exophiala mansonii and between Rhinocladiella aquaspersa and Exophiala jeanselmei. This clade of dematiaceous hyphomycetes was a sister group to a clade comprising members of two orders of cleistothecial ascomycetes, Eurotiales and Onygenales. The etiological agents of chromoblastomycosis were found to be a closely related group (clade), while the agents of phaeohyphomycosis displayed a broader distribution on the SSU rDNA tree.
Topics: Ascomycota; Base Sequence; DNA Primers; DNA, Ribosomal; Genes, Fungal; Humans; Mitosporic Fungi; Molecular Sequence Data; Mycoses; Phylogeny; RNA, Fungal; RNA, Ribosomal
PubMed: 7615749
DOI: 10.1128/jcm.33.5.1322-1326.1995 -
Frontiers in Plant Science 2023Brown Stem Rot (BSR), caused by the soil borne fungal pathogen , can reduce soybean yields by as much as 38%. Previous allelism studies identified three Resistant to...
Brown Stem Rot (BSR), caused by the soil borne fungal pathogen , can reduce soybean yields by as much as 38%. Previous allelism studies identified three Resistant to brown stem Rot genes (, and ), all mapping to large, overlapping regions on soybean chromosome 16. However, recent fine-mapping and genome wide association studies (GWAS) suggest , and are alleles of a single locus. To address this conflict, we characterized the locus using the Williams82 reference genome (Wm82.a4.v1). We identified 120 Receptor-Like Proteins (RLPs), with hallmarks of disease resistance receptor-like proteins (RLPs), which formed five distinct clusters. We developed virus induced gene silencing (VIGS) constructs to target each of the clusters, hypothesizing that silencing the correct RLP cluster would result in a loss of resistance phenotype. The VIGS constructs were tested against resistant genotypes L78-4094 (), PI 437833 (), or PI 437970 (, infected with or mock infected. No loss of resistance phenotype was observed. We then developed VIGS constructs targeting two RLP clusters with a single construct. Construct B1a/B2 silenced resistance in L78-4094, confirming at least two genes confer -mediated resistance to . Failure of B1a/B2 to silence resistance in PI 437833 and PI 437970 suggests additional genes confer BSR resistance in these lines. To identify differentially expressed genes (DEGs) responding to silencing, we conducted RNA-seq of leaf, stem and root samples from B1a/B2 and empty vector control plants infected with or mock infected. B1a/B2 silencing induced DEGs associated with cell wall biogenesis, lipid oxidation, the unfolded protein response and iron homeostasis and repressed numerous DEGs involved in defense and defense signaling. These findings will improve integration of resistance into elite germplasm and provide novel insights into fungal disease resistance.
PubMed: 38259908
DOI: 10.3389/fpls.2023.1292605 -
Journal of Pesticide Science May 2023To elucidate the cause of brown stem rot in the adzuki bean, we re-evaluated the phytotoxins produced in cultures of the causative agent, f. sp. . The ethyl...
To elucidate the cause of brown stem rot in the adzuki bean, we re-evaluated the phytotoxins produced in cultures of the causative agent, f. sp. . The ethyl acetate-soluble acidic fraction of the culture, as well as the neutral fraction, inhibited the growth of alfalfa seedlings. In the neutral fraction, known phytotoxins gregatin A, B, and C or D and penicilliol A were present. Although the phytotoxins in the acidic fraction were unstable, liquid chromatography-mass spectrometry analysis of the partially purified material suggested that one phytotoxin present was the non-methylated gregatin desmethyl-gregatin A (gregatinic acid A).
PubMed: 37361487
DOI: 10.1584/jpestics.D22-070 -
Nihon Ishinkin Gakkai Zasshi = Japanese... 2007We report a case of a 67-year-old woman with chromomycosis on the left upper arm. The plaque was a very small, erythematous and scaly lesion with a diameter of 1.5 cm.... (Review)
Review
[A case of chromomycosis caused by Fonsecaea pedrosoi presenting as a small plaque on the left upper arm: a review of reported cases of dematiaceous fungal infection in Japan].
We report a case of a 67-year-old woman with chromomycosis on the left upper arm. The plaque was a very small, erythematous and scaly lesion with a diameter of 1.5 cm. Fonsecaea pedrosoi was isolated as the causal fungus, and a number of Phialophora type conidia, the formation of which is considered rare, were observed. Treatment involved surgical excision of the lesion with a 5 mm margin. Follow up three years later revealed no recurrence. In Japan, 536 patients with chromomycosis were reported from 1955 to 2004. This consisted of 296 cases from 1955 to 1981 as reported by Fukushiro, and 240 cases from 1982 to 2004 as reviewed by us. Our examination of data showed that the most common causal fungi was F. pedrosoi with 137 cases (57.15%), followed by Exophiala jeanselmei with a total of 41 cases (17.15%), other fungal species comprised of 16 cases (6.7%), Phialophora verrucosa in 9 cases ( 3.8%) and E. dermatitidis in 4 cases (1.7%). Compared to the previous report by Fukushiro, the incidence of infection with E. jeanselmei had increased. Of the 235 cases we reported, the site of infection involved: upper extremities in 91 (38.7%), face and neck in 42 (17.9%), buttocks in 41 (17.4%), lower extremities in 33 (14%) and body in 23 (9.8%). Compared to Fukushiro's report, cases affecting the lower extremities had decreased, whilst cases involving the buttocks had increased. Overall, the treatment for chromomycosis was either oral administration of antifungal agents, excision, thermotherapy, or a combination of these methods.
Topics: Aged; Arm; Ascomycota; Chromoblastomycosis; Female; Humans
PubMed: 17502843
DOI: 10.3314/jjmm.48.85 -
Journal of Clinical Microbiology Nov 2007Numerous members of the genus Exophiala are potential agents of human and animal mycoses. The majority of these infections are cutaneous and superficial, but also fatal...
Numerous members of the genus Exophiala are potential agents of human and animal mycoses. The majority of these infections are cutaneous and superficial, but also fatal systemic infections are known. We re-identified 188 clinical isolates from the United States, which had a preliminary morphological identification of Exophiala species, by sequencing internal transcribed spacer (ITS) region of the rRNA. Molecular identifications of the strains were as follows, in order of frequency: 55 E. dermatitidis (29.3%), 37 E. xenobiotica (19.7%), 35 E. oligosperma (18.6%), 13 E. lecanii-corni (6.9%), 12 E. phaeomuriformis (6.4%), 7 E. jeanselmei (3.7%), 7 E. bergeri (3.7%), 6 E. mesophila (3.2%), 5 E. spinifera (2.7%), 3 Exophiala sp. 1 (1.6%), 3 E. attenuata (1.6%), 3 Phialophora europaea (1.3%), 1 E. heteromorpha (0.5%), and 1 Exophiala sp. 2 (0.5%) strains. Exophiala strains were repeatedly isolated from deep infections (39.9%) involving lung, pleural fluid, sputum, digestive organs (stomach, intestines, bile), heart, brain, spleen, bone marrow, blood, dialysis fluid, lymph node, joint, breast, middle ear, throat, and intraocular tissues. About 38.3% of the Exophiala spp. strains were agents of cutaneous infections including skin, mucous membranes, nail, and corneal epithelium lesions. The other strains caused superficial infections (0.5%, including hair) or subcutaneous infection (12.0%, including paranasal sinusitis, mycetoma, and subcutaneous cyst). The systemic infections were preponderantly caused by E. dermatitidis, E. oligosperma, E. phaeomuriformis, E. xenobiotica, and E. lecanii-corni. Strains of E. bergeri, E. spinifera, E. jeanselmei, E. mesophila, and E. attenuata mainly induced cutaneous and subcutaneous infections. Since relatively few unknown ITS motifs were encountered, we suppose that the list of opportunistic Exophiala species in temperate climates is nearing completion, but a number of species still have to be described.
Topics: Brain; DNA, Ribosomal Spacer; Exophiala; Humans; Microbial Sensitivity Tests; Retrospective Studies; Skin
PubMed: 17596364
DOI: 10.1128/JCM.02012-06 -
Plant Disease Jan 2000Brown stem rot is a common but poorly understood vascular wilt disease of soybean. In order to more clearly delimit the causal agent (Phialophora gregata) and...
Brown stem rot is a common but poorly understood vascular wilt disease of soybean. In order to more clearly delimit the causal agent (Phialophora gregata) and distinguish it from other morphologically similar fungi from discolored soybean stems, fungi were isolated on a semi-selective medium from discolored and non-discolored soybean stems collected at random across Iowa, Illinois, Minnesota, Missouri, and Ohio. A total of 11 fungi were commonly isolated and characterized based on colony morphology and DNA sequences of the internal transcribed spacer region of the rDNA operon. Phomopsis longicolla was the most frequently isolated fungus, but it was isolated more commonly from lightly discolored or non-discolored stems than from discolored stems. Phialophora gregata was the next most frequently isolated fungus and was isolated more commonly from discolored stems and more commonly in 1996 than in 1995, which had a warm growing season and relatively little brown stem rot. In inoculation experiments, only P. gregata was capable of causing the vascular discoloration and leaf symptoms typical of brown stem rot; none of the seven isolates could be considered non-defoliating. Two other fungi, Plectosphaerella cucumerina and Gliocladium roseum, were similar in colony morphology to Phialophora gregata but were not pathogenic to soybean, and these may be the same species as those referred to by earlier workers as Acremonium spp. or the non-defoliating form of P. gregata.
PubMed: 30841227
DOI: 10.1094/PDIS.2000.84.1.83 -
MycoKeys 2020During a survey on fungi associated with wood necroses of trees in Germany, strains belonging to the Leotiomycetes and Eurotiomycetes were detected by preliminary...
During a survey on fungi associated with wood necroses of trees in Germany, strains belonging to the Leotiomycetes and Eurotiomycetes were detected by preliminary analyses of ITS sequences. Multi-locus phylogenetic analyses (LSU, ITS, , , depending on genus) of 31 of the 45 strains from and reference strains revealed several new taxa, including , a new genus in the Helotiales (Leotiomycetes) with a collophorina-like asexual morph. Seven species (Helotiales, Leotiomycetes) were treated. The 29 strains from belonged to five species, of which and were dominating; , and were revealed as new species. The genus was reported from for the first time. was combined in and differentiated from , which was resurrected. Asexual morphs of two species (Helotiales, Leotiomycetes) were described, including one new species, . Two species (Phaeomoniellales, Eurotiomycetes) were detected, including the new species . and are reported as host plants of .
PubMed: 32189979
DOI: 10.3897/mycokeys.63.46836 -
Plant Disease Feb 1997Brown stem rot frequently is more severe in no-till cropping systems. Population density of Phialophora gregata was monitored in soybean residue positioned below and on...
Brown stem rot frequently is more severe in no-till cropping systems. Population density of Phialophora gregata was monitored in soybean residue positioned below and on the soil surface. Current season residue was confined in nylon mesh bags that were placed in the field in the fall. Population density of the pathogen was measured monthly through the winter, or seasonally for 30 months, and expressed as CFU per gram of soybean residue. Population dynamics of P. gregata differed in surface residue, compared with buried residue. Population density of P. gregata was not significantly different in buried and surface residue from November/December to April. Beginning in late April or May, population density of P. gregata was significantly greater in surface residue than in buried residue. The population density of P. gregata in surface residue remained above 10 CFU per gram of residue after 30 months in the field. In contrast, the fungus was not detected in buried residue after 11 to 17 months. From November to May, the population destiny of P. gregata in surface residue increased more than 14 times the initial density. In contrast, the density of P. gregata in buried residue increased sixfold by April, then decreased to densities not significantly different from the initial population by May and June. Mass of buried residue decreased more rapidly than that of surface residue during April, May, and June. There was a positive correlation between residue weight and the population density of P. gregata in residue. P. gregata survived longer and at higher population densities in residue positioned on the soil surface (simulated no-till) than in buried residue (simulated conventional tillage). Although inoculum density of P. gregata remained high in surface residue, total inoculum declined because of loss of residue biomass.
PubMed: 30870897
DOI: 10.1094/PDIS.1997.81.2.199 -
Phytopathology Mar 1999ABSTRACT The prevalence of brown stem rot (caused by Phialophora gregata), Heterodera glycines, and Phytophthora sojae in the north central United States was...
ABSTRACT The prevalence of brown stem rot (caused by Phialophora gregata), Heterodera glycines, and Phytophthora sojae in the north central United States was investigated during the fall of 1995 and 1996. Soybean fields were randomly selected using an area-frame sampling design in collaboration with the National Agricultural Statistics Service. Soil and soybean stem samples, along with tillage information, were collected from 1,462 fields in Illinois, Iowa, Minnesota, Missouri, and Ohio. An additional 275 soil samples collected from Indiana were assessed for H. glycines. For each field, the incidence and prevalence of brown stem rot was assessed in 20 soybean stem pieces. The prevalence and recovery (expressed as the percentage of leaf disks colonized) of P. sojae and the prevalence and population densities of H. glycines were determined from the soil samples. The prevalence of brown stem rot ranged from 28% in Missouri to 73% in Illinois; 68 and 72% of the fields in Minnesota and Iowa, respectively, showed symptomatic samples. The incidence of brown stem rot was greater in conservation-till than in conventional-till fields in all states except Minnesota, which had few no-till fields. P. sojae was detected in two-thirds of the soybean fields in Ohio and Minnesota, whereas 63, 55, and 41% of the fields in Iowa, Missouri, and Illinois, respectively, were infested with the pathogen. The recovery rates of P. sojae were significantly greater (P = 0.05) in conservation-till than in conventional-till fields in all states except Iowa. H. glycines was detected in 83% of the soybean fields in Illinois, 74% in Iowa, 71% in Missouri, 60% in Ohio, 54% in Minnesota, and 47% in Indiana. Both the prevalence and population densities of H. glycines were consistently greater in tilled than in no-till fields in all states for which tillage information was available.
PubMed: 18944760
DOI: 10.1094/PHYTO.1999.89.3.204