Fusarium oxysporum has been described as a pathogen causing onychomycosis, its incidence has been increasing in immunocompetent and disseminated infection can occur in immunosuppressed individuals. ...We describe the first case of congenital onychomycosis in a child caused by Fusarium oxysporum. The infection being acquired in utero was proven by molecular methods with the identification of the fungus both in the nail and placenta, most probably as an ascending contamination/infection in a HIV-positive, immunosuppressed mother.
The presence of endophytes promotes the biosynthesis of secondary plant metabolites. In this study, endophytic fungi were isolated from
Schinus terebinthifolius
to investigate their diversity and ...antimicrobial activity. A total of 272 endophytic fungi was obtained. These belonged to nine different genera:
Alternaria
,
Colletotrichum, Diaporthe, Epicoccum, Fusarium, Pestalotiopsis, Phyllosticta, Xylaria
, and
Cryptococcus
. Notably,
Diaporthe foliorum
was introduced as a new species, with accompanying morphological descriptions, illustrations, and a multigene phylogenetic analysis (using ITS, TEF1, TUB, HIS, and CAL). Among the 26 fungal morphotypes evaluated for antimicrobial activity, five strains had inhibitory effects against pathogenic microorganisms.
Xylaria allantoidea
CMRP1424 extracts showed antimicrobial activity against
Escherichia coli
,
Pseudomonas aeruginosa,
and
Staphylococcus aureus
.
Diaporthe terebinthifolii
CMRP1430 and CMRP1436 showed antimicrobial activity against
E. coli
,
P. aeruginosa
,
S
.
aureus
, and
C. albicans
. Meanwhile,
D. foliorum
CMRP1321 and
D. malorum
CMRP1438 extracts inhibited
C. albicans
alone. Three classes of chemical compounds were identified in
D. foliorum
CMRP1438 extracts: ferric chloride, potassium hydroxide, and vanillin–sulfuric acid. In conclusion, the endophytic isolates were able to produce bioactive agents with pharmaceutical potential as antibacterial and antifungal agents. As such, they may provide fresh leads in the search for new, biological sources of drug therapies.
The human mutilating disease chromoblastomycosis is caused by melanized members of the order Chaetothyriales. To assess population diversity among 123 clinical strains of agents of the disease in ...Brazil we applied sequencing of the rDNA internal transcribed spacer region, and partial cell division cycle and β-tubulin genes. Strains studied were limited to three clusters divided over the single family Herpotrichiellaceae known to comprise agents of the disease. A Fonsecaea cluster contained the most important agents, among which F. pedrosoi was prevalent with 80% of the total set of strains, followed by 13% for F. monophora, 3% for F. nubica, and a single isolate of F. pugnacius. Additional agents, among which two novel species, were located among members of the genus Rhinocladiella and Cyphellophora, with frequencies of 3% and 1%, respectively.
Chromoblastomycosis is a neglected disease characterized by cutaneous, subcutaneous or disseminated lesions. It is considered an occupational infectious disease that affects mostly rural workers ...exposed to contaminated soil and vegetal matter. Lesions mostly arise after a traumatic inoculation of herpotrichiellaceous fungi from the Chaetothyriales order. However, the environmental niche of the agents of the disease remains obscure. Its association with insects has been predicted in a few studies. Therefore, the present work aimed to analyze if social insects, specifically ants, bees, and termites, provide a suitable habitat for the fungi concerned. The mineral oil flotation method was used to isolate the microorganisms. Nine isolates were recovered and phylogenetic analysis identified two strains as potential agents of chromoblastomycosis, i.e., Fonsecaea pedrosoi CMRP 3076, obtained from a termite nest (n = 1) and Rhinocladiella similis CMRP 3079 from an ant exoskeleton (n = 1). In addition, we also identified Fonsecaea brasiliensis CMRP 3445 from termites (n = 1), Exophiala xenobiotica CMRP 3077 from ant exoskeleton (n = 1), Cyphellophoraceae CMRP 3103 from bees (n = 1), Cladosporium sp. CMRP 3119 from bees (n = 1), Hawksworthiomyces sp. CMRP 3102 from termites (n = 1), and Cryptendoxyla sp. from termites (n = 2). The environmental isolate of F. pedrosoi CMRP 3076 was tested in two animal models, Tenebrio molitor and Wistar rat, for its pathogenic potential with fungal retention in T. molitor tissue. In the Wistar rat, the cells resembling muriform cells were observed 30 d after inoculation.
•Isolation of two species known as agents of chromoblastomycosis.•Virulence potential of environmental Fonsecaea pedrosoi in Tenebrio molitor.•Structures resembling muriform cells present in Wistar rat tissue.
Vulvovaginal candidiasis affects women of reproductive age, which represents approximately 15–25% of vaginitis cases. The present study aimed to isolate and characterize yeast from the patients ...irrespective of the presentation of clinical symptoms. The isolates were subjected to in vitro susceptibility profile and characterization by molecular markers, which intended to assess the distribution of species. A total of 40 isolates were obtained and identified through the CHROMagar, API20aux and by ITS and D1/D2 regions sequencing of DNAr gene. Candida albicans strains were genotyped by the ABC system and the isolates were divided into two genotypic groups. The identity of the C. albicans, C. glabrata, C. guilliermondii, C. kefyr and Saccharomyces cerevisiae isolates was confirmed by the multilocus analysis. The strains of Candida, isolated from patients with complications, were found to be resistant to nystatin but sensitive to fluconazole, amphotericin B and ketoconazole, as observed by in vitro sensitivity profile. The isolates from asymptomatic patients, i.e., the colonized group, showed a dose-dependent sensitivity to the anti-fungal agents, fluconazole and amphotericin B. However, the isolates of C. albicans that belong to distinct genotypic groups showed the same in vitro susceptibility profile.
The present study assessed the diversity of black yeast-like fungi present on babassu coconut shells, a substrate rich in lipids and several volatile organic compounds (VOCs) including aromatic ...hydrocarbons. Using different isolation methods, one-hundred-six isolates were obtained and were identified by ITS sequencing as members of the genera Exophiala, Cladophialophora, Veronaea, and Rhinocladiella. Two novel species were discovered. Eight strains were selected for assessing their ability to grow on toluene and phenyl acetate as the sole carbon and energy source. All strains tested were able to assimilate phenyl acetate, while two out of eight were able to use toluene. VOCs profiling in babassu samples was also investigated by GC-ToF MS, revealing that a complex mixture of VOCs was emitted, which included alkylbenzenes such as toluene. Assimilation of alkylbenzenes by the black yeasts might therefore be the result of evolutionary adaptation to symbiotic interactions with higher plants. The potential relationship between lipid/aromatic hydrocarbon metabolism and pathogenicity is also discussed.
The fungal genus
comprises etiological agents of human chromoblastomycosis, a chronic implantation skin disease. The current hypothesis is that patients acquire the infection through an injury from ...plant material. The present study aimed to evaluate a model of infection in plant and animal hosts to understand the parameters of trans-kingdom pathogenicity. Clinical strains of causative agents of chromoblastomycosis (
and
) were compared with a strain of
isolated from a living plant. The clinical strains of
and
remained concentrated near the epidermis, whereas
colonized deeper plant tissues, resembling an endophytic behavior. In an invertebrate infection model with larvae of a beetle,
exhibited the lowest survival rates. However,
produced dark, spherical to ovoidal cells that resembled muriform cells, the invasive form of human chromoblastomycosis confirming the role of muriform cells as a pathogenic adaptation in animal tissues. An immunologic assay in BALB/c mice demonstrated the high virulence of saprobic species in animal models was subsequently controlled via host higher immune response.
and
are genera of black yeast-like fungi harboring agents of a mutilating implantation disease in humans, along with strictly environmental species. The current hypothesis suggests that those species ...reside in somewhat adverse microhabitats, and pathogenic siblings share virulence factors enabling survival in mammal tissue after coincidental inoculation driven by pathogenic adaptation. A comparative genomic analysis of environmental and pathogenic siblings of
and
was undertaken, including
assembly of
from plant material. The genome size of
species varied between 33.39 and 35.23 Mb, and the core genomes of those species comprises almost 70% of the genes. Expansions of protein domains such as glyoxalases and peptidases suggested ability for pathogenicity in clinical agents, while the use of nitrogen and degradation of phenolic compounds was enriched in environmental species. The similarity of carbohydrate-active vs. protein-degrading enzymes associated with the occurrence of virulence factors suggested a general tolerance to extreme conditions, which might explain the opportunistic tendency of
sibling species. Virulence was tested in the
model and immunological assays were performed in order to support this hypothesis. Larvae infected by environmental
had a lower survival. Fungal macrophage murine co-culture showed that
induced high levels of TNF-α contributing to macrophage activation that could increase the ability to control intracellular fungal growth although hyphal death were not observed, suggesting a higher level of extremotolerance of environmental species.
Candida species are the main cause of hospital acquired fungal bloodstream infections. The main risk factors for candidemia include parenteral nutrition, long-term intensive care, neutropenia, ...diabetes, abdominal surgery and the use of central venous catheters. The antifungal drugs used to treat candidemia are mainly the echinocandins, however some isolates may be resistant to these drugs.
This work aims to evaluate the in vitro susceptibility patterns of various Candida species isolated from blood samples and provide their identification by molecular characterization.
Antifungal susceptibility testing was performed using the broth microdilution method. The sequencing of the ITS and D1/D2 regions of rDNA was used for molecular characterization.
Seventy-four of the 80 isolates were susceptible to anidulafungin, 5 were intermediate, and 1 was resistant. For micafungin 67 were susceptible, 8 were intermediate and 5 were resistant. All isolates were susceptible to amphotericin B. Lastly, 65 isolates were susceptible to fluconazole, 8 were dose-dependent and 4 were resistant. The molecular identification corroborated the phenotypic data in 91.3% of the isolates.
Antifungal susceptibility data has an important role in the treatment of candidemia episodes. It was also concluded that the molecular analysis of isolates provides an accurate identification and identifies genetic variability within Candida species isolated from patients with candidemia.
Chromoblastomycosis is a chronic, cutaneous or subcutaneous mycosis characterized by the presence of muriform cells in host tissue. Implantation disease is caused by melanized fungi related to black ...yeasts, which, in humid tropical climates, are mainly members of the genus
. In endemic areas of Brazil,
and
are the prevalent species. The current hypothesis of infection is traumatic introduction via plant materials, especially by plant thorns. However, isolation studies have demonstrated a low frequency of the agents in environmental substrates. The present study aimed to detect
and
in shells of babassu coconuts, soil, plant debris, and thorns from endemic areas of chromoblastomycosis in Maranhão state, northern Brazil, using Rolling Circle Amplification (RCA) with padlock probes as a new environmental screening tool for agents of chromoblastomycosis. In addition to molecular screening, the environmental samples were analyzed by fungal isolation using mineral oil flotation. The limit of detection of the RCA method was 2.88 × 10
copies of DNA per sample for the used padlock probes, indicating that this represents an efficient and sensitive molecular tool for the environmental screening of
agents. In contrast, with isolation from the same samples using several selective methods, no agents of chromoblastomycosis were recovered.
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