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Journal of Fungi (Basel, Switzerland) Feb 2019Onychomycosis is mainly caused by two dermatophyte species, and . A study of nail invasion mechanisms revealed that the secreted subtilisin Sub6, which has never been... (Review)
Review
Onychomycosis is mainly caused by two dermatophyte species, and . A study of nail invasion mechanisms revealed that the secreted subtilisin Sub6, which has never been detected under in vitro growth conditions, was the main protease secreted by and during infection. In contrast, most of the proteases secreted during the digestion of keratin in vitro were not detected in infected nails. The hypothesis that proteases isolated from dermatophytes grown in a keratin medium are virulence factors is no longer supported. Non-dermatophyte fungi can also be infectious agents in nails. It is necessary to identify the infectious fungus in onychomycosis to prescribe adequate treatment, as moulds such as spp. and spp. are insensitive to standard treatments with terbinafine or itraconazole, which are usually applied for dermatophytes. In these refractory cases, topical amphotericin B treatment has shown to be effective. Terbinafine treatment failure against dermatophytes is also possible, and is usually due to resistance caused by a missense mutation in the squalene epoxidase enzyme targeted by the drug. resistance to terbinafine treatment is an emerging problem, and a switch to azole-based treatment may be necessary to cure such cases of onychomycosis.
PubMed: 30813287
DOI: 10.3390/jof5010020 -
Indian Journal of Microbiology Mar 2022Fungi are one of the most widely distributed microorganisms in the environment, including food such as fruits, vegetables and other crops, posing a potential threat to...
Fungi are one of the most widely distributed microorganisms in the environment, including food such as fruits, vegetables and other crops, posing a potential threat to food safety and human health. The aim of this study was to determine the diversity, intensity and drug resistance of potentially pathogenic filamentous fungi isolated from the fresh raspberries ( L.). A total of 50 strains belonging to genera , , , , , , and were tested for drug resistance against 11 antifungals by disc diffusion and gradient strips methods. The average mycological contamination in the examined samples of raspberries amounted to 4.34 log CFU/g. The was isolated from all tested samples, followed by and with a frequency of 61% and 34%, respectively. The highest level of drug resistance was observed for genera and strains recorded a wide variation in drug resistance as revealed by susceptibility with amphotericin B and voriconzole with MICs ranged from 0.5-4 µg/ml and posaconazole with MICs ranging from 3-8 µg/ml. All fungal strains showed 100% resistance to caspofungin, fluconazole and flucytosine with both the methods, and 100% resistance to micafungin and anidulafungin in the gradient strip method.
PubMed: 35068614
DOI: 10.1007/s12088-021-00966-y -
Biological Reviews of the Cambridge... Oct 2022Verticillium dahliae is a notorious soil-borne pathogen that enters hosts through the roots and proliferates in the plant water-conducting elements to cause Verticillium... (Review)
Review
Verticillium dahliae is a notorious soil-borne pathogen that enters hosts through the roots and proliferates in the plant water-conducting elements to cause Verticillium wilt. Historically, Verticillium wilt symptoms have been explained by vascular occlusion, due to the accumulation of mycelia and plant biomacromolecule aggregation, and also by phytotoxicity caused by pathogen-secreted toxins. Beyond the direct cytotoxicity of some members of the secretome, this review systematically discusses the roles of the V. dahliae secretome in vascular occlusion, including the deposition of polysaccharides as an outcome of plant cell wall destruction, the accumulation of fungal mycelia, and modulation of plant defence responses. By modulating plant defences and hormone levels, the secretome manipulates the vascular environment to induce Verticillium wilt. Thus, the secretome of V. dahliae colludes with plant defence responses to modulate Verticillium wilt symptoms, and thereby bridges the historical concepts of both toxin production by the pathogen and vascular occlusion as the cause of wilting symptoms.
Topics: Acremonium; Ascomycota; Plant Diseases; Secretome; Verticillium
PubMed: 35478378
DOI: 10.1111/brv.12863 -
Biomolecular Concepts Apr 2013Peroxisomes are ubiquitous organelles that enclose catalases, fatty acid-oxidizing enzymes, and a variety of proteins involved in different cellular processes.... (Review)
Review
Peroxisomes are ubiquitous organelles that enclose catalases, fatty acid-oxidizing enzymes, and a variety of proteins involved in different cellular processes. Interestingly, the late enzymes involved in penicillin biosynthesis, and the isopenicillin N epimerization enzymes involved in cephalosporin biosynthesis are located inside peroxisomes in the producer fungi Penicillium chrysogenum and Acremonium chrysogenum. Peroxisome proteins are targeted to those organelles by peroxisomal targeting signals located at the C-terminus (PTS1) or near the N-terminal end (PTS2) of those proteins. Peroxisomal membrane proteins (PMPs) are largely recruited by the interaction with specific sequences in the Pex19 protein. The compartmentalization into peroxisomes of several steps of the biosynthesis of penicillin, cephalosporin, and other secondary metabolites raises the question of how the precursors and/or intermediates of the biosynthesis of β-lactam antibiotics are transported into peroxisomes and the mechanisms of secretion of the final products (penicillin or cephalosporin) from peroxisomes to the extracellular medium. Recent advances in peroxisome proteomics, immunoelectron microscopy, and fluorescence labeling have shown that the transport of these intermediates is mediated by membrane proteins of the major facilitator superfamily class (drug/H+ antiporters) containing 12 transmembrane-spanning domains (TMS). In some cases, the transport of the substrates (e.g., fatty acids) or intermediates may be mediated by ATP-binding cassette (ABC) transporters. Knowledge on the transport and secretion mechanisms is of paramount importance to understand the complex mechanisms of cell differentiation and their crosstalk with the biosynthesis of different secondary metabolites that act as biochemical signals between the producer cells and also as communication signals with competing microorganisms (e.g., antimicrobial agents or plant elicitors).
Topics: Acremonium; Animals; Anti-Bacterial Agents; Biological Transport; Cephalosporins; Humans; Intracellular Membranes; Lactams; Molecular Sequence Data; Penicillins; Penicillium chrysogenum; Peroxisomes; Sequence Analysis, Protein
PubMed: 25436576
DOI: 10.1515/bmc-2012-0048 -
Neural Regeneration Research Sep 2019Fungi are important infectious disease-causing agents, but are often overlooked as environmental factors in disease. We review several lines of evidence that point to a... (Review)
Review
Fungi are important infectious disease-causing agents, but are often overlooked as environmental factors in disease. We review several lines of evidence that point to a potential fungal origin of sporadic amyotrophic lateral sclerosis (ALS), the most common form of motor neurone disease. Approximately 90% cases of ALS are sporadic, and the aetiology of sporadic ALS is still unknown. We have previously postulated that grass or soil-associated fungal infections may be a leading cause of sporadic ALS. Herein we extend this proposal to water-associated fungi. A wide variety of fungi have been reported in drinking water including Acremonium, Alternaria, Aspergillus, Cladosporium, Fusarium, Penicillium and Trichoderma. Some of these are known to produce neurotoxic mycotoxins. Despite this, drinking water is not routinely monitored for fungal contamination. Fungal contamination could explain the close correlation between distribution of well water and cases of sporadic ALS in the United States. We propose several mechanisms by which an opportunistic fungal infection from environmental exposure (to water, soil or plants) can lead to long term neuronal degradation resulting in the hallmarks of ALS. If confirmed, the association between fungal infection and sporadic ALS could lead to novel treatment strategies for this progressive and fatal disease.
PubMed: 31089037
DOI: 10.4103/1673-5374.255959 -
Indian Journal of Ophthalmology Oct 2022To study the risk factors, clinical presentation, management options, and outcomes in cases of culture-proven Acremonium keratitis.
PURPOSE
To study the risk factors, clinical presentation, management options, and outcomes in cases of culture-proven Acremonium keratitis.
METHODS
Medical and microbiology records of culture-proven Acremonium keratitis from Jan 2007 to Dec 2019 at a tertiary eye care center were reviewed. Details of clinical findings on each visit and operating notes were reviewed from the medical records. All cases were subjected to corneal scraping at the first visit for microbiological investigation consisting of direct smear examination and culture. Topical natamycin 5% was the mainstay of medical treatment. Surgical treatment was considered for nonresponding patients.
RESULTS
During the 13-year study period, 65 cases of culture-proven Acremonium keratitis were identified out of 1605 cases of fungal keratitis. Trauma was the most common predisposing factor in 32 cases (49.2%). The average area of the corneal stromal infiltrate was 24.8 mm at the initial presentation. Hypopyon at the time of presentation was evident in 28 (43.1%) cases. Staphylococcus spp. was the most common (n = 22, 33.8%) organism coexistent with Acremonium. Direct microscopy of corneal scraping was positive for fungal filaments in 57/65 (87.6%) cases. Medical management alone was given in 44 patients (67.6%). Age (>50 years) and treatment delay (>15 days) were found to be independent risk factors for the poor final visual outcome (VA <20/60).
CONCLUSION
When treated early, Acremonium keratitis responds well to medical therapy with currently available topical antifungals. However, advanced and nonresponding cases require surgical intervention for resolution of the infection.
Topics: Acremonium; Antifungal Agents; Corneal Diseases; Eye Infections, Fungal; Humans; Keratitis; Middle Aged; Natamycin; Retrospective Studies; Risk Factors
PubMed: 36190039
DOI: 10.4103/ijo.IJO_659_22 -
Life (Basel, Switzerland) Jan 2024There has been a substantial increase in the number of cases of invasive fungal infections worldwide, which is associated with a growing number of immunosuppressed... (Review)
Review
There has been a substantial increase in the number of cases of invasive fungal infections worldwide, which is associated with a growing number of immunosuppressed patients and a rise in antifungal resistance. Some fungi that were previously considered harmless to humans have become emerging pathogens. One of them is , a ubiquitous filamentous fungus commonly found in the environment, especially in the air and soil. belongs to a bigger group of hyaline fungi that cause hyalohyphomycosis, a fungal infection caused by fungi with colorless hyphae. Although this is a heterogeneous group of fungi, there are similarities regarding their ubiquity, ways of transmission, affected patients, and difficulties in diagnostics and treatment. In hyalohyphomycosis, the skin is one of the most affected organs, which is why the involvement of dermatologists is crucial for the initial assessment, since the timely recognition and early diagnosis of this condition can prevent life-threatening infections and death. In this review, we covered cutaneous hyalohyphomycosis caused by and other fungi in the same group, including , , , , , and genera.
PubMed: 38276283
DOI: 10.3390/life14010154 -
Synthetic and Systems Biotechnology Sep 2016is an important filamentous fungus which produces cephalosporin C in industry. This review summarized the study on genetic engineering of , including biosynthesis and... (Review)
Review
is an important filamentous fungus which produces cephalosporin C in industry. This review summarized the study on genetic engineering of , including biosynthesis and regulation for fermentation of cephalosporin C, molecular techniques, molecular breeding and transcriptomics of . We believe with all the techniques available and full genomic sequence, the industrial strain of can be genetically modified to better serve the pharmaceutical industry.
PubMed: 29062938
DOI: 10.1016/j.synbio.2016.09.002 -
Microorganisms Aug 2018is known to be regularly isolated from food and also to be a cause of human disease. Herein, we resolve some sources of confusion that have strongly hampered the...
is known to be regularly isolated from food and also to be a cause of human disease. Herein, we resolve some sources of confusion that have strongly hampered the accurate interpretation of these and other isolations. The recently designated type species of the genus , , is known only from a single isolate, but it is the closest known relative of what may be one of the planet's most successful organisms, , shown herein to be best called by its earliest valid name, . The sequencing of ribosomal internal transcribed spacer (ITS) regions, actin genes, or both for 72 study isolates within this group allowed the full range of morphotypes and ITS barcode types to be elucidated, along with information on temperature tolerance and habitat. The results showed that nomenclatural confusion and frequent misidentifications facilitated by morphotaxonomy, along with misidentified early sequence deposits, have obscured the reality that this species is, in many ways, the definitive match of the historical concept of : a pale orange or dull greenish-coloured monophialidic hyphomycete, forming cylindrical, ellipsoidal, or obovoid conidia in sticky heads or obovoid conidia in dry chains, and acting ecologically as a soil organism, marine organism, plant pathogen, plant endophyte, probable insect pathogen, human opportunistic pathogen, food contaminant, probable dermatological communicable disease agent, and heat-tolerant spoilage organism. Industrially, it is already in exploratory use as a producer of the antibiotic ascofuranone, active against trypanosomes, cryptosporidia, and microsporidia, and additional applications are in development. The genus-level clarification of the phylogeny of shows other historic acremonia belong to separate genera, and two are here described, for the complex and for the complex.
PubMed: 30115839
DOI: 10.3390/microorganisms6030088 -
Frontiers in Microbiology 2022Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has emerged as a powerful microorganism identification tool. Research on...
Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has emerged as a powerful microorganism identification tool. Research on MALDI-TOF MS identification of rare filamentous fungi is still lacking. This study aimed to evaluate the performance of MALDI-TOF MS in the identification of , -like, , and species. Sabouraud broth cultivation and formic acid/acetonitrile protein extraction were used for MALDI-TOF MS identification by a Bruker Biotyper system. An in-house database containing 29 isolates of , -like, , and spp. was constructed. A total of 52 clinical isolates were identified using the Bruker Filamentous Fungi Library v1.0 (FFL v1.0) alone, and Filamentous Fungi Library v1.0 plus the in-house library, respectively. The mass spectrum profile (MSP) dendrograms of the 28 isolates, 26 -like isolates, and 27 and isolates were constructed by MALDI Biotyper OC 4.0 software, respectively. The correct species identification rate significantly improved when using the combined databases compared with that when using FFL v1.0 alone ( spp., 75% versus 0%; -like spp., 100% versus 0%; and spp., 100% versus 62.5%). The MSP dendrograms differentiated -like species, and species clearly, but cannot distinguish species in the complex. In conclusion, with an expanded database, MALDI-TOF MS is an effective tool for the identification of , -like, , and species.
PubMed: 35308359
DOI: 10.3389/fmicb.2022.841286