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Stemler J, Többen C, Lass-Flörl C, Steinmann J, Ackermann K, Rath PM, Simon M, Cornely OA, Koehler P. Diagnosis and Treatment of Invasive Aspergillosis Caused by Non- fumigatus Aspergillus spp. J Fungi (Basel) 2023; 9:jof9040500. [PMID: 37108955 PMCID: PMC10141595 DOI: 10.3390/jof9040500] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 03/27/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
With increasing frequency, clinical and laboratory-based mycologists are consulted on invasive fungal diseases caused by rare fungal species. This review aims to give an overview of the management of invasive aspergillosis (IA) caused by non-fumigatus Aspergillus spp.-namely A. flavus, A. terreus, A. niger and A. nidulans-including diagnostic and therapeutic differences and similarities to A. fumigatus. A. flavus is the second most common Aspergillus spp. isolated in patients with IA and the predominant species in subtropical regions. Treatment is complicated by its intrinsic resistance against amphotericin B (AmB) and high minimum inhibitory concentrations (MIC) for voriconazole. A. nidulans has been frequently isolated in patients with long-term immunosuppression, mostly in patients with primary immunodeficiencies such as chronic granulomatous disease. It has been reported to disseminate more often than other Aspergillus spp. Innate resistance against AmB has been suggested but not yet proven, while MICs seem to be elevated. A. niger is more frequently reported in less severe infections such as otomycosis. Triazoles exhibit varying MICs and are therefore not strictly recommended as first-line treatment for IA caused by A. niger, while patient outcome seems to be more favorable when compared to IA due to other Aspergillus species. A. terreus-related infections have been reported increasingly as the cause of acute and chronic aspergillosis. A recent prospective international multicenter surveillance study showed Spain, Austria, and Israel to be the countries with the highest density of A. terreus species complex isolates collected. This species complex seems to cause dissemination more often and is intrinsically resistant to AmB. Non-fumigatus aspergillosis is difficult to manage due to complex patient histories, varying infection sites and potential intrinsic resistances to antifungals. Future investigational efforts should aim at amplifying the knowledge on specific diagnostic measures and their on-site availability, as well as defining optimal treatment strategies and outcomes of non-fumigatus aspergillosis.
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Affiliation(s)
- Jannik Stemler
- Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD), European Diamond Excellence Center for Medical Mycology (ECMM), Faculty of Medicine, University Hospital of Cologne, University of Cologne, 50937 Cologne, Germany
- Institute of Translational Research, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50923 Cologne, Germany
- German Centre for Infection Research (DZIF), Partner Site Bonn-Cologne, 50923 Cologne, Germany
| | - Christina Többen
- Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD), European Diamond Excellence Center for Medical Mycology (ECMM), Faculty of Medicine, University Hospital of Cologne, University of Cologne, 50937 Cologne, Germany
- Institute of Translational Research, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50923 Cologne, Germany
- German Centre for Infection Research (DZIF), Partner Site Bonn-Cologne, 50923 Cologne, Germany
| | - Cornelia Lass-Flörl
- Institute of Hygiene and Medical Microbiology, European Diamond Excellence Center for Medical Mycology (ECMM), Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Jörg Steinmann
- Institute of Clinical Hygiene, Medical Microbiology and Infectiology, Paracelsus Medical University, Klinikum Nürnberg, 90419 Nuremberg, Germany
- Institute of Medical Microbiology, University Hospital Essen, European Diamond Excellence Center for Medical Mycology (ECMM), 45147 Essen, Germany
| | - Katharina Ackermann
- Institute of Clinical Hygiene, Medical Microbiology and Infectiology, Paracelsus Medical University, Klinikum Nürnberg, 90419 Nuremberg, Germany
| | - Peter-Michael Rath
- Institute of Medical Microbiology, University Hospital Essen, European Diamond Excellence Center for Medical Mycology (ECMM), 45147 Essen, Germany
| | - Michaela Simon
- Institute for Medical Microbiology, Immunology and Hygiene, Faculty of Medicine, University Hospital of Cologne, University of Cologne, 50937 Cologne, Germany
| | - Oliver Andreas Cornely
- Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD), European Diamond Excellence Center for Medical Mycology (ECMM), Faculty of Medicine, University Hospital of Cologne, University of Cologne, 50937 Cologne, Germany
- Institute of Translational Research, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50923 Cologne, Germany
- German Centre for Infection Research (DZIF), Partner Site Bonn-Cologne, 50923 Cologne, Germany
- Clinical Trials Centre Cologne (ZKS Köln), University of Cologne, 50935 Cologne, Germany
| | - Philipp Koehler
- Department I of Internal Medicine, Center for Integrated Oncology Aachen Bonn Cologne Duesseldorf (CIO ABCD), European Diamond Excellence Center for Medical Mycology (ECMM), Faculty of Medicine, University Hospital of Cologne, University of Cologne, 50937 Cologne, Germany
- Institute of Translational Research, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, 50923 Cologne, Germany
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Anti-Alzheimer's disease potential of traditional chinese medicinal herbs as inhibitors of BACE1 and AChE enzymes. Biomed Pharmacother 2022; 154:113576. [PMID: 36007279 DOI: 10.1016/j.biopha.2022.113576] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/09/2022] [Accepted: 08/16/2022] [Indexed: 12/31/2022] Open
Abstract
Alzheimer's disease (AD) is a common neurodegenerative disease that often occurs in the elderly population. At present, most drugs for AD on the market are single-target drugs, which have achieved certain success in the treatment of AD. However, the efficacy and safety of single-target drugs have not achieved the expected results because AD is a multifactorial disease. Multi-targeted drugs act on multiple factors of the disease network to improve efficacy and reduce adverse reactions. Therefore, the search for effective dual-target or even multi-target drugs has become a new research trend. Many of results found that the dual-target inhibitors of the beta-site amyloid precursor protein cleaving enzyme 1 (BACE1) and acetylcholinesterase (AChE) found from traditional Chinese medicine have a good inhibitory effect on AD with fewer side effects. This article reviews sixty-six compounds extracted from Chinese medicinal herbs, which have inhibitory activity on BACE1 and AChE. This provides a theoretical basis for the further development of these compounds as dual-target inhibitors for the treatment of AD.
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Tang S, Men P, Zhang W, Li H, Li Z, Huang X, Lu X. Identification of a polyketide biosynthesis gene cluster by transcriptional regulator activation in Aspergillus terreus. Fungal Genet Biol 2022; 160:103690. [DOI: 10.1016/j.fgb.2022.103690] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 03/10/2022] [Accepted: 03/23/2022] [Indexed: 11/27/2022]
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Genome sequencing of the neotype strain CBS 554.65 reveals the MAT1-2 locus of Aspergillus niger. BMC Genomics 2021; 22:679. [PMID: 34548025 PMCID: PMC8454179 DOI: 10.1186/s12864-021-07990-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 09/03/2021] [Indexed: 12/05/2022] Open
Abstract
Background Aspergillus niger is a ubiquitous filamentous fungus widely employed as a cell factory thanks to its abilities to produce a wide range of organic acids and enzymes. Its genome was one of the first Aspergillus genomes to be sequenced in 2007, due to its economic importance and its role as model organism to study fungal fermentation. Nowadays, the genome sequences of more than 20 A. niger strains are available. These, however, do not include the neotype strain CBS 554.65. Results The genome of CBS 554.65 was sequenced with PacBio. A high-quality nuclear genome sequence consisting of 17 contigs with a N50 value of 4.07 Mbp was obtained. The assembly covered all the 8 centromeric regions of the chromosomes. In addition, a complete circular mitochondrial DNA assembly was obtained. Bioinformatic analyses revealed the presence of a MAT1-2-1 gene in this genome, contrary to the most commonly used A. niger strains, such as ATCC 1015 and CBS 513.88, which contain a MAT1-1-1 gene. A nucleotide alignment showed a different orientation of the MAT1–1 locus of ATCC 1015 compared to the MAT1–2 locus of CBS 554.65, relative to conserved genes flanking the MAT locus. Within 24 newly sequenced isolates of A. niger half of them had a MAT1–1 locus and the other half a MAT1–2 locus. The genomic organization of the MAT1–2 locus in CBS 554.65 is similar to other Aspergillus species. In contrast, the region comprising the MAT1–1 locus is flipped in all sequenced strains of A. niger. Conclusions This study, besides providing a high-quality genome sequence of an important A. niger strain, suggests the occurrence of genetic flipping or switching events at the MAT1–1 locus of A. niger. These results provide new insights in the mating system of A. niger and could contribute to the investigation and potential discovery of sexuality in this species long thought to be asexual. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07990-8.
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Abstract
Infections due to Aspergillus species are an acute threat to human health; members of the Aspergillus section Fumigati are the most frequently occurring agents, but depending on the local epidemiology, representatives of section Terrei or section Flavi are the second or third most important. Aspergillus terreus species complex is of great interest, as it is usually amphotericin B resistant and displays notable differences in immune interactions in comparison to Aspergillus fumigatus. The latest epidemiological surveys show an increased incidence of A. terreus as well as an expanding clinical spectrum (chronic infections) and new groups of at-risk patients being affected. Hallmarks of these non-Aspergillus fumigatus invasive mold infections are high potential for tissue invasion, dissemination, and possible morbidity due to mycotoxin production. We seek to review the microbiology, epidemiology, and pathogenesis of A. terreus species complex, address clinical characteristics, and highlight the underlying mechanisms of amphotericin B resistance. Selected topics will contrast key elements of A. terreus with A. fumigatus. We provide a comprehensive resource for clinicians dealing with fungal infections and researchers working on A. terreus pathogenesis, aiming to bridge the emerging translational knowledge and future therapeutic challenges on this opportunistic pathogen.
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Moore GG. Practical considerations will ensure the continued success of pre-harvest biocontrol using non-aflatoxigenic Aspergillus flavus strains. Crit Rev Food Sci Nutr 2021; 62:4208-4225. [PMID: 33506687 DOI: 10.1080/10408398.2021.1873731] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
There is an important reason for the accelerated use of non-aflatoxigenic Aspergillus flavus to mitigate pre-harvest aflatoxin contamination… it effectively addresses the imperative need for safer food and feed. Now that we have decades of proof of the effectiveness of A. flavus as biocontrol, it is time to improve several aspects of this strategy. If we are to continue relying heavily on this form of aflatoxin mitigation, there are considerations we must acknowledge, and actions we must take, to ensure that we are best wielding this strategy to our advantage. These include its: (1) potential to produce other mycotoxins, (2) persistence in the field in light of several ecological factors, (3) its reproductive and genetic stability, (4) the mechanism(s) employed that allow it to elicit control over aflatoxigenic strains and species of agricultural importance and (5) supplemental alternatives that increase its effectiveness. There is a need to be consistent, practical and thoughtful when it comes to implementing this method of mycotoxin mitigation since these fungi are living organisms that have been adapting, evolving and surviving on this planet for tens-of-millions of years. This document will serve as a critical review of the literature regarding pre-harvest A. flavus biocontrol and will discuss opportunities for improvements.
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Affiliation(s)
- Geromy G Moore
- United States Department of Agriculture, Agricultural Research Service, New Orleans, USA
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Ellena V, Sauer M, Steiger MG. The fungal sexual revolution continues: discovery of sexual development in members of the genus Aspergillus and its consequences. Fungal Biol Biotechnol 2020; 7:17. [PMID: 33357234 PMCID: PMC7761153 DOI: 10.1186/s40694-020-00107-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 12/15/2020] [Indexed: 12/24/2022] Open
Abstract
Asexuality was considered to be a common feature of a large part of fungi, including those of the genus Aspergillus. However, recent advances and the available genomic and genetic engineering technologies allowed to gather more and more indications of a hidden sexuality in fungi previously considered asexual. In parallel, the acquired knowledge of the most suitable conditions for crossings was shown to be crucial to effectively promote sexual reproduction in the laboratory. These discoveries not only have consequences on our knowledge of the biological processes ongoing in nature, questioning if truly asexual fungal species exist, but they also have important implications on other research areas. For instance, the presence of sexuality in certain fungi can have effects on their pathogenicity or on shaping the ecosystem that they normally colonize. For these reasons, further investigations of the sexual potential of Aspergillus species, such as the industrially important A. niger, will be carried on.
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Affiliation(s)
- Valeria Ellena
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), Muthgasse 18, Vienna, Austria. .,Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Vienna, Austria.
| | - Michael Sauer
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), Muthgasse 18, Vienna, Austria.,Institute of Microbiology and Microbial Biotechnology, BOKU-VIBT, University of Natural Resources and Life Sciences, Muthgasse 18, Vienna, Austria.,CD Laboratory for Biotechnology of Glycerol, Muthgasse 18, Vienna, Austria
| | - Matthias G Steiger
- Austrian Centre of Industrial Biotechnology (ACIB GmbH), Muthgasse 18, Vienna, Austria.,Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Vienna, Austria
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Korfanty G, Stanley K, Lammers K, Fan Y, Xu J. Variations in sexual fitness among natural strains of the opportunistic human fungal pathogen Aspergillus fumigatus. INFECTION GENETICS AND EVOLUTION 2020; 87:104640. [PMID: 33246083 DOI: 10.1016/j.meegid.2020.104640] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 10/05/2020] [Accepted: 11/21/2020] [Indexed: 10/22/2022]
Abstract
Aspergillus fumigatus is a ubiquitous ascomycete fungus, naturally inhabiting the soil and compost piles. Its conidia readily disperse into the atmosphere and cause opportunistic infections known as aspergillosis. With the emerging resistance to many antifungal drugs, our understanding of A. fumigatus epidemiology has become increasingly important for developing effective control and treatment strategies. As a pathogen capable of both sexual and asexual reproduction, mutations causing drug resistance and increased virulence could be spread rapidly in A. fumigatus populations. However, relatively little is known about the distributions of sexual reproductive fitness among natural strains of A. fumigatus. Here we investigated the formation of sexual reproductive structure (i.e. cleistothecia) and sexual spore viability among 60 natural strains of A. fumigatus. These strains were from six geographically distant countries (India, China, Canada, Cameroon, Saudi Arabia, and New Zealand), with 10 strains (including five MAT1-1 strains and five MAT1-2 strains) from each country. These strains were crossed in all combinations with strains of the opposite mating type. In addition, all 60 strains were crossed with either AFB62-1 (MAT1-1) or AFIR928 (MAT1-2), two reference supermater strains. Of the 900 crosses among the 60 natural strains, 136 crosses (15.1%) produced cleistothecia. Our analyses revealed that strains from China had the highest average ability to form cleistothecia, followed by those from New Zealand, Saudi Arabia, India, Canada, and Cameroon. Among the crosses that produced cleistothecia, about 40% produced viable ascospores, with the rate of ascospore germination varied significantly among crosses. Interestingly, neither the ability to form cleistothecia nor ascospore germination rate showed any distinct relationships with either geographic or genetic distance between parental strains. Our results suggest that genetic exchange among geographically and genetically divergent strains of A. fumigatus are possible. However, the rates of genetic exchange likely vary among strains and populations in nature.
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Affiliation(s)
- Greg Korfanty
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Kaitlin Stanley
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Kaitlyn Lammers
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - YuYing Fan
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Jianping Xu
- Department of Biology, McMaster University, Hamilton, Ontario, Canada.
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Mohammad TH, Risan MH, El-Hiti GA, Ahmed DS, Yousif E. Successful in-vivo treatment of mice infected with Candida glabrata using silver nanoparticles. BIONATURA 2020. [DOI: 10.21931/rb/2020.05.04.10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The current study describes the production of silver nanoparticles (AgNPs) to treat Candida glabrata infections. The method involved incubation of silver nitrate (AgNO3) with Aspergillus terreus using a green and straightforward route. The production of AgNPs was confirmed through a color change from transparent yellow to brown as well as by ultraviolet-visible (UV-VIS) spectroscopy. The surface morphology of AgNPs was assessed using a scanning electron microscope. The antifungal activity of AgNPs against C. glabrata was investigated in the serum of 20 infected mice. The mice were divided into four groups, and the level of cytokines: IL-4 and IFN-γ were examined after 21 days. The atomic force microscopy confirmed that the average diameter of AgNPs was 25.1 nm, which is appropriate for delivering silver nanoparticles to treat animals' infection. The concentration of cytokines IL-4 and IFN-γ were significantly (P < 0.05) higher in the C. glabrata-infected group than in the control group. While the cytokines level remained close to average concentration in mice administrated with AgNPs, such a result was comparable with the fourth group of mice (Candida-treated Aspergillus) after treatment with AgNPs.
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Affiliation(s)
- Teeba H. Mohammad
- Department of Molecular and Medical Biotechnology, College of Biotechnology, Al-Nahrain University, Baghdad, Iraq
| | - Mohsen H. Risan
- Department of Molecular and Medical Biotechnology, College of Biotechnology, Al-Nahrain University, Baghdad, Iraq
| | - Gamal A. El-Hiti
- Cornea Research Chair, Department of Optometry, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Dina S. Ahmed
- Department of Medical Instrumentation Engineering, Al-Mansour University College, Baghdad, Iraq
| | - Emad Yousif
- Department of Chemistry, College of Science, Al-Nahrain University, Baghdad, Iraq
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Jørgensen TR, Burggraaf AM, Arentshorst M, Schutze T, Lamers G, Niu J, Kwon MJ, Park J, Frisvad JC, Nielsen KF, Meyer V, van den Hondel CA, Dyer PS, Ram AF. Identification of SclB, a Zn(II)2Cys6 transcription factor involved in sclerotium formation in Aspergillus niger. Fungal Genet Biol 2020; 139:103377. [DOI: 10.1016/j.fgb.2020.103377] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 02/07/2020] [Accepted: 02/14/2020] [Indexed: 10/24/2022]
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Houbraken J, Kocsubé S, Visagie C, Yilmaz N, Wang XC, Meijer M, Kraak B, Hubka V, Bensch K, Samson R, Frisvad J. Classification of Aspergillus, Penicillium, Talaromyces and related genera ( Eurotiales): An overview of families, genera, subgenera, sections, series and species. Stud Mycol 2020; 95:5-169. [PMID: 32855739 PMCID: PMC7426331 DOI: 10.1016/j.simyco.2020.05.002] [Citation(s) in RCA: 240] [Impact Index Per Article: 60.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The Eurotiales is a relatively large order of Ascomycetes with members frequently having positive and negative impact on human activities. Species within this order gain attention from various research fields such as food, indoor and medical mycology and biotechnology. In this article we give an overview of families and genera present in the Eurotiales and introduce an updated subgeneric, sectional and series classification for Aspergillus and Penicillium. Finally, a comprehensive list of accepted species in the Eurotiales is given. The classification of the Eurotiales at family and genus level is traditionally based on phenotypic characters, and this classification has since been challenged using sequence-based approaches. Here, we re-evaluated the relationships between families and genera of the Eurotiales using a nine-gene sequence dataset. Based on this analysis, the new family Penicillaginaceae is introduced and four known families are accepted: Aspergillaceae, Elaphomycetaceae, Thermoascaceae and Trichocomaceae. The Eurotiales includes 28 genera: 15 genera are accommodated in the Aspergillaceae (Aspergillago, Aspergillus, Evansstolkia, Hamigera, Leiothecium, Monascus, Penicilliopsis, Penicillium, Phialomyces, Pseudohamigera, Pseudopenicillium, Sclerocleista, Warcupiella, Xerochrysium and Xeromyces), eight in the Trichocomaceae (Acidotalaromyces, Ascospirella, Dendrosphaera, Rasamsonia, Sagenomella, Talaromyces, Thermomyces, Trichocoma), two in the Thermoascaceae (Paecilomyces, Thermoascus) and one in the Penicillaginaceae (Penicillago). The classification of the Elaphomycetaceae was not part of this study, but according to literature two genera are present in this family (Elaphomyces and Pseudotulostoma). The use of an infrageneric classification system has a long tradition in Aspergillus and Penicillium. Most recent taxonomic studies focused on the sectional level, resulting in a well-established sectional classification in these genera. In contrast, a series classification in Aspergillus and Penicillium is often outdated or lacking, but is still relevant, e.g., the allocation of a species to a series can be highly predictive in what functional characters the species might have and might be useful when using a phenotype-based identification. The majority of the series in Aspergillus and Penicillium are invalidly described and here we introduce a new series classification. Using a phylogenetic approach, often supported by phenotypic, physiologic and/or extrolite data, Aspergillus is subdivided in six subgenera, 27 sections (five new) and 75 series (73 new, one new combination), and Penicillium in two subgenera, 32 sections (seven new) and 89 series (57 new, six new combinations). Correct identification of species belonging to the Eurotiales is difficult, but crucial, as the species name is the linking pin to information. Lists of accepted species are a helpful aid for researchers to obtain a correct identification using the current taxonomic schemes. In the most recent list from 2014, 339 Aspergillus, 354 Penicillium and 88 Talaromyces species were accepted. These numbers increased significantly, and the current list includes 446 Aspergillus (32 % increase), 483 Penicillium (36 % increase) and 171 Talaromyces (94 % increase) species, showing the large diversity and high interest in these genera. We expanded this list with all genera and species belonging to the Eurotiales (except those belonging to Elaphomycetaceae). The list includes 1 187 species, distributed over 27 genera, and contains MycoBank numbers, collection numbers of type and ex-type cultures, subgenus, section and series classification data, information on the mode of reproduction, and GenBank accession numbers of ITS, beta-tubulin (BenA), calmodulin (CaM) and RNA polymerase II second largest subunit (RPB2) gene sequences.
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Key Words
- Acidotalaromyces Houbraken, Frisvad & Samson
- Acidotalaromyces lignorum (Stolk) Houbraken, Frisvad & Samson
- Ascospirella Houbraken, Frisvad & Samson
- Ascospirella lutea (Zukal) Houbraken, Frisvad & Samson
- Aspergillus chaetosartoryae Hubka, Kocsubé & Houbraken
- Classification
- Evansstolkia Houbraken, Frisvad & Samson
- Evansstolkia leycettana (H.C. Evans & Stolk) Houbraken, Frisvad & Samson
- Hamigera brevicompacta (H.Z. Kong) Houbraken, Frisvad & Samson
- Infrageneric classification
- New combinations, series
- New combinations, species
- New genera
- New names
- New sections
- New series
- New taxa
- Nomenclature
- Paecilomyces lagunculariae (C. Ram) Houbraken, Frisvad & Samson
- Penicillaginaceae Houbraken, Frisvad & Samson
- Penicillago kabunica (Baghd.) Houbraken, Frisvad & Samson
- Penicillago mirabilis (Beliakova & Milko) Houbraken, Frisvad & Samson
- Penicillago moldavica (Milko & Beliakova) Houbraken, Frisvad & Samson
- Phialomyces arenicola (Chalab.) Houbraken, Frisvad & Samson
- Phialomyces humicoloides (Bills & Heredia) Houbraken, Frisvad & Samson
- Phylogeny
- Polythetic classes
- Pseudohamigera Houbraken, Frisvad & Samson
- Pseudohamigera striata (Raper & Fennell) Houbraken, Frisvad & Samson
- Talaromyces resinae (Z.T. Qi & H.Z. Kong) Houbraken & X.C. Wang
- Talaromyces striatoconidius Houbraken, Frisvad & Samson
- Taxonomic novelties: New family
- Thermoascus verrucosus (Samson & Tansey) Houbraken, Frisvad & Samson
- Thermoascus yaguchii Houbraken, Frisvad & Samson
- in Aspergillus: sect. Bispori S.W. Peterson, Varga, Frisvad, Samson ex Houbraken
- in Aspergillus: ser. Acidohumorum Houbraken & Frisvad
- in Aspergillus: ser. Inflati (Stolk & Samson) Houbraken & Frisvad
- in Penicillium: sect. Alfrediorum Houbraken & Frisvad
- in Penicillium: ser. Adametziorum Houbraken & Frisvad
- in Penicillium: ser. Alutacea (Pitt) Houbraken & Frisvad
- sect. Crypta Houbraken & Frisvad
- sect. Eremophila Houbraken & Frisvad
- sect. Formosana Houbraken & Frisvad
- sect. Griseola Houbraken & Frisvad
- sect. Inusitata Houbraken & Frisvad
- sect. Lasseniorum Houbraken & Frisvad
- sect. Polypaecilum Houbraken & Frisvad
- sect. Raperorum S.W. Peterson, Varga, Frisvad, Samson ex Houbraken
- sect. Silvatici S.W. Peterson, Varga, Frisvad, Samson ex Houbraken
- sect. Vargarum Houbraken & Frisvad
- ser. Alliacei Houbraken & Frisvad
- ser. Ambigui Houbraken & Frisvad
- ser. Angustiporcata Houbraken & Frisvad
- ser. Arxiorum Houbraken & Frisvad
- ser. Atramentosa Houbraken & Frisvad
- ser. Aurantiobrunnei Houbraken & Frisvad
- ser. Avenacei Houbraken & Frisvad
- ser. Bertholletiarum Houbraken & Frisvad
- ser. Biplani Houbraken & Frisvad
- ser. Brevicompacta Houbraken & Frisvad
- ser. Brevipedes Houbraken & Frisvad
- ser. Brunneouniseriati Houbraken & Frisvad
- ser. Buchwaldiorum Houbraken & Frisvad
- ser. Calidousti Houbraken & Frisvad
- ser. Canini Houbraken & Frisvad
- ser. Carbonarii Houbraken & Frisvad
- ser. Cavernicolarum Houbraken & Frisvad
- ser. Cervini Houbraken & Frisvad
- ser. Chevalierorum Houbraken & Frisvad
- ser. Cinnamopurpurea Houbraken & Frisvad
- ser. Circumdati Houbraken & Frisvad
- ser. Clavigera Houbraken & Frisvad
- ser. Conjuncti Houbraken & Frisvad
- ser. Copticolarum Houbraken & Frisvad
- ser. Coremiiformes Houbraken & Frisvad
- ser. Corylophila Houbraken & Frisvad
- ser. Costaricensia Houbraken & Frisvad
- ser. Cremei Houbraken & Frisvad
- ser. Crustacea (Pitt) Houbraken & Frisvad
- ser. Dalearum Houbraken & Frisvad
- ser. Deflecti Houbraken & Frisvad
- ser. Egyptiaci Houbraken & Frisvad
- ser. Erubescentia (Pitt) Houbraken & Frisvad
- ser. Estinogena Houbraken & Frisvad
- ser. Euglauca Houbraken & Frisvad
- ser. Fennelliarum Houbraken & Frisvad
- ser. Flavi Houbraken & Frisvad
- ser. Flavipedes Houbraken & Frisvad
- ser. Fortuita Houbraken & Frisvad
- ser. Fumigati Houbraken & Frisvad
- ser. Funiculosi Houbraken & Frisvad
- ser. Gallaica Houbraken & Frisvad
- ser. Georgiensia Houbraken & Frisvad
- ser. Goetziorum Houbraken & Frisvad
- ser. Gracilenta Houbraken & Frisvad
- ser. Halophilici Houbraken & Frisvad
- ser. Herqueorum Houbraken & Frisvad
- ser. Heteromorphi Houbraken & Frisvad
- ser. Hoeksiorum Houbraken & Frisvad
- ser. Homomorphi Houbraken & Frisvad
- ser. Idahoensia Houbraken & Frisvad
- ser. Implicati Houbraken & Frisvad
- ser. Improvisa Houbraken & Frisvad
- ser. Indica Houbraken & Frisvad
- ser. Japonici Houbraken & Frisvad
- ser. Jiangxiensia Houbraken & Frisvad
- ser. Kalimarum Houbraken & Frisvad
- ser. Kiamaensia Houbraken & Frisvad
- ser. Kitamyces Houbraken & Frisvad
- ser. Lapidosa (Pitt) Houbraken & Frisvad
- ser. Leporum Houbraken & Frisvad
- ser. Leucocarpi Houbraken & Frisvad
- ser. Livida Houbraken & Frisvad
- ser. Longicatenata Houbraken & Frisvad
- ser. Macrosclerotiorum Houbraken & Frisvad
- ser. Monodiorum Houbraken & Frisvad
- ser. Multicolores Houbraken & Frisvad
- ser. Neoglabri Houbraken & Frisvad
- ser. Neonivei Houbraken & Frisvad
- ser. Nidulantes Houbraken & Frisvad
- ser. Nigri Houbraken & Frisvad
- ser. Nivei Houbraken & Frisvad
- ser. Nodula Houbraken & Frisvad
- ser. Nomiarum Houbraken & Frisvad
- ser. Noonimiarum Houbraken & Frisvad
- ser. Ochraceorosei Houbraken & Frisvad
- ser. Olivimuriarum Houbraken & Frisvad
- ser. Osmophila Houbraken & Frisvad
- ser. Paradoxa Houbraken & Frisvad
- ser. Paxillorum Houbraken & Frisvad
- ser. Penicillioides Houbraken & Frisvad
- ser. Phoenicea Houbraken & Frisvad
- ser. Pinetorum (Pitt) Houbraken & Frisvad
- ser. Polypaecilum Houbraken & Frisvad
- ser. Pulvini Houbraken & Frisvad
- ser. Quercetorum Houbraken & Frisvad
- ser. Raistrickiorum Houbraken & Frisvad
- ser. Ramigena Houbraken & Frisvad
- ser. Restricti Houbraken & Frisvad
- ser. Robsamsonia Houbraken & Frisvad
- ser. Rolfsiorum Houbraken & Frisvad
- ser. Roseopurpurea Houbraken & Frisvad
- ser. Rubri Houbraken & Frisvad
- ser. Salinarum Houbraken & Frisvad
- ser. Samsoniorum Houbraken & Frisvad
- ser. Saturniformia Houbraken & Frisvad
- ser. Scabrosa Houbraken & Frisvad
- ser. Sclerotigena Houbraken & Frisvad
- ser. Sclerotiorum Houbraken & Frisvad
- ser. Sheariorum Houbraken & Frisvad
- ser. Simplicissima Houbraken & Frisvad
- ser. Soppiorum Houbraken & Frisvad
- ser. Sparsi Houbraken & Frisvad
- ser. Spathulati Houbraken & Frisvad
- ser. Spelaei Houbraken & Frisvad
- ser. Speluncei Houbraken & Frisvad
- ser. Spinulosa Houbraken & Frisvad
- ser. Stellati Houbraken & Frisvad
- ser. Steyniorum Houbraken & Frisvad
- ser. Sublectatica Houbraken & Frisvad
- ser. Sumatraensia Houbraken & Frisvad
- ser. Tamarindosolorum Houbraken & Frisvad
- ser. Teporium Houbraken & Frisvad
- ser. Terrei Houbraken & Frisvad
- ser. Thermomutati Houbraken & Frisvad
- ser. Thiersiorum Houbraken & Frisvad
- ser. Thomiorum Houbraken & Frisvad
- ser. Unguium Houbraken & Frisvad
- ser. Unilaterales Houbraken & Frisvad
- ser. Usti Houbraken & Frisvad
- ser. Verhageniorum Houbraken & Frisvad
- ser. Versicolores Houbraken & Frisvad
- ser. Virgata Houbraken & Frisvad
- ser. Viridinutantes Houbraken & Frisvad
- ser. Vitricolarum Houbraken & Frisvad
- ser. Wentiorum Houbraken & Frisvad
- ser. Westlingiorum Houbraken & Frisvad
- ser. Whitfieldiorum Houbraken & Frisvad
- ser. Xerophili Houbraken & Frisvad
- series Tularensia (Pitt) Houbraken & Frisvad
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Affiliation(s)
- J. Houbraken
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
| | - S. Kocsubé
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - C.M. Visagie
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, P. Bag X20, Hatfield, Pretoria, 0028, South Africa
| | - N. Yilmaz
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, P. Bag X20, Hatfield, Pretoria, 0028, South Africa
| | - X.-C. Wang
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, No. 3, 1st Beichen West Road, Chaoyang District, Beijing, 100101, China
| | - M. Meijer
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
| | - B. Kraak
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
| | - V. Hubka
- Department of Botany, Charles University in Prague, Prague, Czech Republic
| | - K. Bensch
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
| | - R.A. Samson
- Westerdijk Fungal Biodiversity Institute, Utrecht, The Netherlands
| | - J.C. Frisvad
- Department of Biotechnology and Biomedicine Technical University of Denmark, Søltofts Plads, B. 221, Kongens Lyngby, DK 2800, Denmark
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12
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Metin B, Döğen A, Yıldırım E, de Hoog GS, Heitman J, Ilkit M. Mating type (MAT) locus and possible sexuality of the opportunistic pathogen Exophiala dermatitidis. Fungal Genet Biol 2019; 124:29-38. [PMID: 30611834 DOI: 10.1016/j.fgb.2018.12.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 12/27/2018] [Accepted: 12/30/2018] [Indexed: 11/27/2022]
Abstract
Sexual reproduction among the black yeasts is generally limited to environmental saprobic species and is rarely observed among opportunists in humans. To date, a complete sexual cycle has not been observed in Exophiala dermatitidis. In this study, we aimed to gain insight into the reproductive mode of E. dermatitidis by characterizing its mating type (MAT) locus, conducting MAT screening of environmental and clinical isolates, examining the expression of the MAT genes and analyzing the virulence of the isolates of different mating types. Similar to other members of the Pezizomycotina, the E. dermatitidis genome harbors a high mobility group (HMG) domain gene (MAT1-2-1) in the vicinity of the SLA2 and APN2 genes. The MAT loci of 74 E. dermatitidis isolates (11 clinical and 63 environmental) were screened by PCR, and the surrounding region was amplified using long-range PCR. Sequencing of the ∼ 12-kb PCR product of a MAT1-1 isolate revealed an α-box gene (MAT1-1-1). The MAT1-1 idiomorph was 3544-bp long and harbored the MAT1-1-1 and MAT1-1-4 genes. The MAT1-2 idiomorph was longer, 3771-bp, and harbored only the MAT1-2-1 gene. This structure suggests a heterothallic reproduction mode. The distribution of MAT among 74 isolates was ∼ 1:1 with a MAT1-1:MAT1-2 ratio of 35:39. RT-PCR analysis indicated that the MAT genes are transcribed. No significant difference was detected in the virulence of isolates representing different mating types using a Galleria mellonella model (P > 0.05). Collectively, E. dermatitidis is the first opportunistic black yeast in which both MAT idiomorphs have been characterized. The occurrence of isolates bearing both idiomorphs, their approximately equal distribution, and the expression of the MAT genes suggest that E. dermatitidis might reproduce sexually.
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Affiliation(s)
- Banu Metin
- Department of Food Engineering, Faculty of Engineering and Natural Sciences, Istanbul Sabahattin Zaim University, Istanbul, Turkey.
| | - Aylin Döğen
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Mersin University, Mersin, Turkey.
| | - Esra Yıldırım
- Department of Food Engineering, Faculty of Engineering and Natural Sciences, Istanbul Sabahattin Zaim University, Istanbul, Turkey.
| | - G Sybren de Hoog
- Westerdijk Fungal Biodiversity Institute, Utrecht, the Netherlands; Center of Expertise in Mycology of Radboudumc/CWZ, Nijmegen, the Netherlands.
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA.
| | - Macit Ilkit
- Division of Mycology, Department of Microbiology, Faculty of Medicine, Çukurova University, Adana, Turkey.
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13
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Hubka V, Barrs V, Dudová Z, Sklenář F, Kubátová A, Matsuzawa T, Yaguchi T, Horie Y, Nováková A, Frisvad J, Talbot J, Kolařík M. Unravelling species boundaries in the Aspergillus viridinutans complex (section Fumigati): opportunistic human and animal pathogens capable of interspecific hybridization. PERSOONIA 2018; 41:142-174. [PMID: 30728603 PMCID: PMC6344812 DOI: 10.3767/persoonia.2018.41.08] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 03/14/2018] [Indexed: 12/13/2022]
Abstract
Although Aspergillus fumigatus is the major agent of invasive aspergillosis, an increasing number of infections are caused by its cryptic species, especially A. lentulus and the A. viridinutans species complex (AVSC). Their identification is clinically relevant because of antifungal drug resistance and refractory infections. Species boundaries in the AVSC are unresolved since most species have uniform morphology and produce interspecific hybrids in vitro. Clinical and environmental strains from six continents (n = 110) were characterized by DNA sequencing of four to six loci. Biological compatibilities were tested within and between major phylogenetic clades, and ascospore morphology was characterised. Species delimitation methods based on the multispecies coalescent model (MSC) supported recognition of ten species including one new species. Four species are confirmed opportunistic pathogens; A. udagawae followed by A. felis and A. pseudoviridinutans are known from opportunistic human infections, while A. felis followed by A. udagawae and A. wyomingensis are agents of feline sino-orbital aspergillosis. Recently described human-pathogenic species A. parafelis and A. pseudofelis are synonymized with A. felis and an epitype is designated for A. udagawae. Intraspecific mating assay showed that only a few of the heterothallic species can readily generate sexual morphs in vitro. Interspecific mating assays revealed that five different species combinations were biologically compatible. Hybrid ascospores had atypical surface ornamentation and significantly different dimensions compared to parental species. This suggests that species limits in the AVSC are maintained by both pre- and post-zygotic barriers and these species display a great potential for rapid adaptation and modulation of virulence. This study highlights that a sufficient number of strains representing genetic diversity within a species is essential for meaningful species boundaries delimitation in cryptic species complexes. MSC-based delimitation methods are robust and suitable tools for evaluation of boundaries between these species.
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Affiliation(s)
- V. Hubka
- Department of Botany, Faculty of Science, Charles University, Benátská 2, 128 01 Prague 2, Czech Republic
- Laboratory of Fungal Genetics and Metabolism, Institute of Microbiology of the CAS, v.v.i, Vídeňská 1083, 142 20 Prague 4, Czech Republic
- First Faculty of Medicine, Charles University, Kateřinská 32, 121 08 Prague 2, Czech Republic
| | - V. Barrs
- Sydney School of Veterinary Science, Faculty of Science, and Marie Bashir Institute of Infectious Diseases & Biosecurity, University of Sydney, Camperdown, NSW, Australia
| | - Z. Dudová
- Department of Botany, Faculty of Science, Charles University, Benátská 2, 128 01 Prague 2, Czech Republic
- First Faculty of Medicine, Charles University, Kateřinská 32, 121 08 Prague 2, Czech Republic
| | - F. Sklenář
- Department of Botany, Faculty of Science, Charles University, Benátská 2, 128 01 Prague 2, Czech Republic
- Laboratory of Fungal Genetics and Metabolism, Institute of Microbiology of the CAS, v.v.i, Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - A. Kubátová
- Department of Botany, Faculty of Science, Charles University, Benátská 2, 128 01 Prague 2, Czech Republic
| | - T. Matsuzawa
- University of Nagasaki, 1-1-1 Manabino, Nagayo-cho, Nishi-Sonogi-gun, Nagasaki 851-2195, Japan
| | - T. Yaguchi
- Medical Mycology Research Center, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba 260-8673, Japan
| | - Y. Horie
- Medical Mycology Research Center, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba 260-8673, Japan
| | - A. Nováková
- Laboratory of Fungal Genetics and Metabolism, Institute of Microbiology of the CAS, v.v.i, Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - J.C. Frisvad
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - J.J. Talbot
- Sydney School of Veterinary Science, Faculty of Science, and Marie Bashir Institute of Infectious Diseases & Biosecurity, University of Sydney, Camperdown, NSW, Australia
| | - M. Kolařík
- Laboratory of Fungal Genetics and Metabolism, Institute of Microbiology of the CAS, v.v.i, Vídeňská 1083, 142 20 Prague 4, Czech Republic
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14
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Hennig S, Wenzel M, Haas C, Hoffmann A, Weber J, Rödel G, Ostermann K. New approaches in bioprocess-control: Consortium guidance by synthetic cell-cell communication based on fungal pheromones. Eng Life Sci 2018; 18:387-400. [PMID: 32624919 DOI: 10.1002/elsc.201700181] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 02/08/2018] [Accepted: 03/13/2018] [Indexed: 01/02/2023] Open
Abstract
Bioconversions in industrial processes are currently dominated by single-strain approaches. With the growing complexity of tasks to be carried out, microbial consortia become increasingly advantageous and eventually may outperform single-strain fermentations. Consortium approaches benefit from the combined metabolic capabilities of highly specialized strains and species, and the inherent division of labor reduces the metabolic burden for each strain while increasing product yields and reaction specificities. However, consortium-based designs still suffer from a lack of available tools to control the behavior and performance of the individual subpopulations and of the entire consortium. Here, we propose to implement novel control elements for microbial consortia based on artificial cell-cell communication via fungal mating pheromones. Coupling to the desired output is mediated by pheromone-responsive gene expression, thereby creating pheromone-dependent communication channels between different subpopulations of the consortia. We highlight the benefits of artificial communication to specifically target individual subpopulations of microbial consortia and to control e.g. their metabolic profile or proliferation rate in a predefined and customized manner. Due to the steadily increasing knowledge of sexual cycles of industrially relevant fungi, a growing number of strains and species can be integrated into pheromone-controlled sensor-actor systems, exploiting their unique metabolic properties for microbial consortia approaches.
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Affiliation(s)
- Stefan Hennig
- Institute of Genetics Technische Universität Dresden Dresden Germany
| | - Mandy Wenzel
- Institute of Genetics Technische Universität Dresden Dresden Germany
| | - Christiane Haas
- Institute of Natural Materials Technology Technische Universität Dresden Dresden Germany
| | - Andreas Hoffmann
- Institute of Natural Materials Technology Technische Universität Dresden Dresden Germany
| | - Jost Weber
- Institute of Natural Materials Technology Technische Universität Dresden Dresden Germany.,Evolva Biotec A/S Lersø Parkallé 42 Copenhagen Denmark
| | - Gerhard Rödel
- Institute of Genetics Technische Universität Dresden Dresden Germany
| | - Kai Ostermann
- Institute of Genetics Technische Universität Dresden Dresden Germany
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15
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Halo BA, Al-Yahyai RA, Al-Sadi AM. Aspergillus terreus Inhibits Growth and Induces Morphological Abnormalities in Pythium aphanidermatum and Suppresses Pythium-Induced Damping-Off of Cucumber. Front Microbiol 2018; 9:95. [PMID: 29449831 PMCID: PMC5799290 DOI: 10.3389/fmicb.2018.00095] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 01/16/2018] [Indexed: 01/27/2023] Open
Abstract
The study investigated the efficacy of two isolates of Aspergillus terreus (65P and 9F) on the growth, morphology and pathogenicity of Pythium aphanidermatum on cucumber. In vitro tests showed that the two isolates inhibited the growth of P. aphanidermatum in culture. Investigating P. aphanidermatum hyphae close to the inhibition zone showed that the hyphae showed abnormal growth and loss of internal content. Treating P. aphanidermatum with the culture filtrate (CF) of A. terreus resulted in significant rise in cellular leakage of P. aphanidermatum mycelium. Testing glucanase enzyme activity by both A. terreus isolates showed a significant increase in glucanase activity. This suggests that the cell walls of Pythium, which consist of glucan, are affected by the glucanase enzyme produced by A. terreus. In addition, Aspergillus isolates produced siderephore, which is suggested to be involved in inhibition of Pythium growth. Also, the CFs of 65P and 9F isolates significantly reduced spore production by P. aphanidermatum compared to the control (P < 0.05). In bioassay tests, the two isolates of A. terreus increased the survival rate of cucumber seedlings from 10 to 20% in the control seedlings treated with P. aphanidermatum to 38-39% when the biocontrol agents were used. No disease symptoms were observed on cucumber seedlings only treated with the isolates 65P and 9F of A. terreus. In addition, the A. terreus isolates did not have any negative effects on the growth of cucumber seedlings. This study shows that isolates of A. terreus can help suppress Pythium-induced damping-off of cucumber, which is suggested to be through the effect of A. terreus and its glucanase enzyme on P. aphanidermatum mycelium.
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Affiliation(s)
| | | | - Abdullah M. Al-Sadi
- Department of Crop Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, Muscat, Oman
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16
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Abstract
Approximately 20% of species in the fungal kingdom are only known to reproduce by asexual means despite the many supposed advantages of sexual reproduction. However, in recent years, sexual cycles have been induced in a series of emblematic "asexual" species. We describe how these discoveries were made, building on observations of evidence for sexual potential or "cryptic sexuality" from population genetic analyses; the presence, distribution, and functionality of mating-type genes; genome analyses revealing the presence of genes linked to sexuality; the functionality of sex-related genes; and formation of sex-related developmental structures. We then describe specific studies that led to the discovery of mating and sex in certain Candida, Aspergillus, Penicillium, and Trichoderma species and discuss the implications of sex including the beneficial exploitation of the sexual cycle. We next consider whether there might be any truly asexual fungal species. We suggest that, although rare, imperfect fungi may genuinely be present in nature and that certain human activities, combined with the genetic flexibility that is a hallmark of the fungal kingdom, might favor the evolution of asexuality under certain conditions. Finally, we argue that fungal species should not be thought of as simply asexual or sexual, but rather as being composed of isolates on a continuum of sexual fertility.
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17
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Mi F, Zhang Y, Yang D, Tang X, Wang P, He X, Zhang Y, Dong J, Cao Y, Liu C, Zhang KQ, Xu J. Evidence for Inbreeding and Genetic Differentiation among Geographic Populations of the Saprophytic Mushroom Trogia venenata from Southwestern China. PLoS One 2016; 11:e0149507. [PMID: 26890380 PMCID: PMC4758605 DOI: 10.1371/journal.pone.0149507] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 02/02/2016] [Indexed: 02/05/2023] Open
Abstract
During the past 40 years, more than 400 Sudden Unexplained Deaths (SUDs) have occurred in Yunnan, southwestern China. Epidemiological and toxicological analyses suggested that a newly discovered mushroom called Trogia venenata was the leading culprit for SUDs. At present, relatively little is known about the genetics and natural history of this mushroom. In this study, we analyzed the sequence variation at four DNA fragments among 232 fruiting bodies of T. venenata collected from seven locations. Our ITS sequence analyses confirmed that all the isolates belonged to the same species. The widespread presence of sequence heterozygosity within many strains at each of three protein-coding genes suggested that the fruiting bodies were diploid, dikaryotic or heterokaryotic. Within individual geographic populations, we found significant deviations of genotype frequencies from Hardy-Weinberg expectations, with the overall observed heterozygosity lower than that expected under random mating, consistent with prevalent inbreeding within local populations. The geographic populations were overall genetically differentiated. Interestingly, while a positive correlation was found between population genetic distance and geographic distance, there was little correlation between genetic distance and barium concentration difference for the geographic populations. Our results suggest frequent inbreeding, geographic structuring, and limited gene flow among geographic populations of T. venenata from southwestern China.
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Affiliation(s)
- Fei Mi
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China
- Institute of Communicable Disease Control and Prevention, Guizhou Provincial Centre for Disease Control and Prevention, Guiyang, Guizhou, PR China
| | - Ying Zhang
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China
| | - Dan Yang
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China
| | - Xiaozhao Tang
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China
| | - Pengfei Wang
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China
| | - Xiaoxia He
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China
| | - Yunrun Zhang
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China
| | - Jianyong Dong
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China
| | - Yang Cao
- Yunnan Institute for Tropical Crop Research, Jinghong, Yunnan, PR China
| | - Chunli Liu
- Kunming Edible Fungi Institute of All China Federation of Supply and Marketing Cooperatives, Kunming, Yunnan, PR China
| | - Ke-Qin Zhang
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China
| | - Jianping Xu
- Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
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18
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Frisvad JC, Larsen TO. Extrolites of Aspergillus fumigatus and Other Pathogenic Species in Aspergillus Section Fumigati. Front Microbiol 2016; 6:1485. [PMID: 26779142 PMCID: PMC4703822 DOI: 10.3389/fmicb.2015.01485] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/09/2015] [Indexed: 11/13/2022] Open
Abstract
Aspergillus fumigatus is an important opportunistic human pathogen known for its production of a large array of extrolites. Up to 63 species have been described in Aspergillus section Fumigati, some of which have also been reliably reported to be pathogenic, including A. felis, A. fischeri, A. fumigatiaffinis, A. fumisynnematus, A. hiratsukae, A. laciniosus, A. lentulus, A. novofumigatus, A. parafelis, A. pseudofelis, A. pseudoviridinutans, A. spinosus, A. thermomutatus, and A. udagawae. These species share the production of hydrophobins, melanins, and siderophores and ability to grow well at 37°C, but they only share some small molecule extrolites, that could be important factors in pathogenicity. According to the literature gliotoxin and other exometabolites can be contributing factors to pathogenicity, but these exometabolites are apparently not produced by all pathogenic species. It is our hypothesis that species unable to produce some of these metabolites can produce proxy-exometabolites that may serve the same function. We tabulate all exometabolites reported from species in Aspergillus section Fumigati and by comparing the profile of those extrolites, suggest that those producing many different kinds of exometabolites are potential opportunistic pathogens. The exometabolite data also suggest that the profile of exometabolites are highly specific and can be used for identification of these closely related species.
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Affiliation(s)
- Jens C. Frisvad
- Section of Eukaryotic Biotechnology, Department of Systems Biology, Technical University of DenmarkKongens Lyngby, Denmark
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19
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Lackner M, Coassin S, Haun M, Binder U, Kronenberg F, Haas H, Jank M, Maurer E, Meis JF, Hagen F, Lass-Flörl C. Geographically predominant genotypes of Aspergillus terreus species complex in Austria: s microsatellite typing study. Clin Microbiol Infect 2015; 22:270-6. [PMID: 26577144 DOI: 10.1016/j.cmi.2015.10.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 10/27/2015] [Accepted: 10/28/2015] [Indexed: 11/19/2022]
Abstract
Aspergillus terreus species complex is recognized as a frequent agent of invasive aspergillosis in Tyrol. The reason for this specific epidemiological situation is unclear. Aspergillus terreus strains isolated from environmental and clinical sources were genotyped using a novel panel of short tandem repeats and were evaluated for virulence. Three major endemic genotypes collected from the Inn region and its side valleys were found to cause the majority of invasive A. terreus infections. All of these genotypes were of the same mating type, which suggests that a mating barrier is present between these geographically well-adapted strains which is found to persist for at least 11 years. The three major genotypes were prevalent in both human infections and the environment. No major differences in virulence were observed using Galleria mellonella as model. Our data suggest a specific environmental exposure being responsible for the high incidence of A. terreus infections in Innsbruck, the Inn valley and side valleys (Tyrol, Austria).
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Affiliation(s)
- M Lackner
- Division of Hygiene and Medical Microbiology, Austria.
| | - S Coassin
- Division of Genetic Epidemiology, Austria
| | - M Haun
- Division of Genetic Epidemiology, Austria
| | - U Binder
- Division of Hygiene and Medical Microbiology, Austria
| | | | - H Haas
- Division of Molecular Biology, Medical University of Innsbruck, Austria
| | - M Jank
- Division of Hygiene and Medical Microbiology, Austria
| | - E Maurer
- Division of Hygiene and Medical Microbiology, Austria
| | - J F Meis
- Department of Medical Microbiology and Infectious Diseases, Canisius Wilhelmina Ziekenhuis, Nijmegen, The Netherlands; Department of Medical Microbiology, Radboudumc, Nijmegen, The Netherlands
| | - F Hagen
- Department of Medical Microbiology and Infectious Diseases, Canisius Wilhelmina Ziekenhuis, Nijmegen, The Netherlands
| | - C Lass-Flörl
- Division of Hygiene and Medical Microbiology, Austria
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Frisvad JC, Larsen TO. Chemodiversity in the genus Aspergillus. Appl Microbiol Biotechnol 2015; 99:7859-77. [DOI: 10.1007/s00253-015-6839-z] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 07/08/2015] [Accepted: 07/11/2015] [Indexed: 10/23/2022]
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21
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Dunne K, Prior AR, Murphy K, Wall N, Leen G, Rogers TR, Elnazir B, Greally P, Renwick J, Murphy P. Emergence of persistent Aspergillus terreus colonisation in a child with cystic fibrosis. Med Mycol Case Rep 2015; 9:26-30. [PMID: 26288746 PMCID: PMC4534713 DOI: 10.1016/j.mmcr.2015.07.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 07/07/2015] [Accepted: 07/23/2015] [Indexed: 11/28/2022] Open
Affiliation(s)
- Katie Dunne
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland ; Department of Clinical Microbiology, Trinity Centre for Health Science, Tallaght hospital, Trinity College Dublin, Dublin 24, Ireland
| | - Anna-Rose Prior
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland
| | - Kate Murphy
- Department of Clinical Microbiology, Trinity Centre for Health Science, Tallaght hospital, Trinity College Dublin, Dublin 24, Ireland
| | - Niall Wall
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland
| | - Geraldine Leen
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland
| | - Thomas R Rogers
- Department of Clinical Microbiology, Trinity College Dublin, St James's Hospital, Dublin 8, Ireland
| | - Basil Elnazir
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland
| | - Peter Greally
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland
| | - Julie Renwick
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland ; Department of Clinical Microbiology, Trinity Centre for Health Science, Tallaght hospital, Trinity College Dublin, Dublin 24, Ireland
| | - Philip Murphy
- The National Children's Hospital, Tallaght Hospital, Tallaght, Dublin 24, Ireland ; Department of Clinical Microbiology, Trinity Centre for Health Science, Tallaght hospital, Trinity College Dublin, Dublin 24, Ireland
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Dahlmann TA, Böhm J, Becker K, Kück U. Sexual recombination as a tool for engineering industrial Penicillium chrysogenum strains. Curr Genet 2015; 61:679-83. [PMID: 25993917 DOI: 10.1007/s00294-015-0497-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 05/14/2015] [Indexed: 12/13/2022]
Abstract
The recent discovery and functional characterization of opposite mating-type loci in the industrial penicillin producer Penicillium chrysogenum demonstrated their regulatory role in sexual as well as asexual development. Subsequent experiments further showed that a sexual life cycle can be induced in P. chrysogenum that was for long believed to reproduce exclusively by asexual propagation. Finally, crossing of wild type and production strains resulted in the generation of recombinant ascospore isolates. We predict from these recent findings that recombinant progeny for industrial applications can be obtained by sexual crossings and discuss experimental difficulties that occur when parental strains with karyotype heterogeneity are used for mating.
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Affiliation(s)
- Tim A Dahlmann
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-University Bochum, 44780, Bochum, Germany
| | - Julia Böhm
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-University Bochum, 44780, Bochum, Germany
| | - Kordula Becker
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-University Bochum, 44780, Bochum, Germany
| | - Ulrich Kück
- Lehrstuhl für Allgemeine und Molekulare Botanik, Ruhr-University Bochum, 44780, Bochum, Germany.
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23
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Kathuria S, Sharma C, Singh PK, Agarwal P, Agarwal K, Hagen F, Meis JF, Chowdhary A. Molecular epidemiology and in-vitro antifungal susceptibility of Aspergillus terreus species complex isolates in Delhi, India: evidence of genetic diversity by amplified fragment length polymorphism and microsatellite typing. PLoS One 2015; 10:e0118997. [PMID: 25781896 PMCID: PMC4363790 DOI: 10.1371/journal.pone.0118997] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 01/08/2015] [Indexed: 11/19/2022] Open
Abstract
Aspergillus terreus is emerging as an etiologic agent of invasive aspergillosis in immunocompromised individuals in several medical centers in the world. Infections due to A. terreus are of concern due to its resistance to amphotericin B, in vivo and in vitro, resulting in poor response to antifungal therapy and high mortality. Herein we examined a large collection of molecularly characterized, geographically diverse A. terreus isolates (n = 140) from clinical and environmental sources in India for the occurrence of cryptic A. terreus species. The population structure of the Indian A. terreus isolates and their association with those outside India was determined using microsatellite based typing (STR) technique and Amplified Fragment Length Polymorphism analysis (AFLP). Additionally, in vitro antifungal susceptibility of A. terreus isolates was determined against 7 antifungals. Sequence analyses of the calmodulin locus identified the recently described cryptic species A. hortai, comprising 1.4% of Aspergillus section Terrei isolates cultured from cases of aspergilloma and probable invasive aspergillosis not reported previously. All the nine markers used for STR typing of A. terreus species complex proved to be highly polymorphic. The presence of high genetic diversity revealing 75 distinct genotypes among 101 Indian A. terreus isolates was similar to the marked heterogeneity noticed in the 47 global A. terreus population exhibiting 38 unique genotypes mainly among isolates from North America and Europe. Also, AFLP analysis showed distinct banding patterns for genotypically diverse A. terreus isolates. Furthermore, no correlation between a particular genotype and amphotericin B susceptibility was observed. Overall, 8% of the A. terreus isolates exhibited low MICs of amphotericin B. All the echinocandins and azoles (voriconazole, posaconazole and isavuconazole) demonstrated high potency against all the isolates. The study emphasizes the need of molecular characterization of A. terreus species complex isolates to better understand the ecology, acquisition and transmission of this species.
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Affiliation(s)
- Shallu Kathuria
- Department of Medical Mycology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Cheshta Sharma
- Department of Medical Mycology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Pradeep Kumar Singh
- Department of Medical Mycology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Puneet Agarwal
- Department of Pulmonary Medicine, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
| | - Kshitij Agarwal
- Department of Pulmonary Medicine, Rajan Babu Institute of Pulmonary Medicine and Tuberculosis, Delhi, India
| | - Ferry Hagen
- Department of Medical Microbiology and Infectious Diseases, Canisius-Wilhelmina Hospital, Nijmegen, The Netherlands
| | - Jacques F. Meis
- Department of Medical Microbiology and Infectious Diseases, Canisius-Wilhelmina Hospital, Nijmegen, The Netherlands
- Department of Medical Microbiology, Radboudumc, Nijmegen, The Netherlands
| | - Anuradha Chowdhary
- Department of Medical Mycology, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India
- * E-mail:
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Hull CM, Purdy NJ, Moody SC. Mitigation of human-pathogenic fungi that exhibit resistance to medical agents: can clinical antifungal stewardship help? Future Microbiol 2015; 9:307-25. [PMID: 24762306 DOI: 10.2217/fmb.13.160] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Reducing indiscriminate antimicrobial usage to combat the expansion of multidrug-resistant human-pathogenic bacteria is fundamental to clinical antibiotic stewardship. In contrast to bacteria, fungal resistance traits are not understood to be propagated via mobile genetic elements, and it has been proposed that a global explosion of resistance to medical antifungals is therefore unlikely. Clinical antifungal stewardship has focused instead on reducing the drug toxicity and high costs associated with medical agents. Mitigating the problem of human-pathogenic fungi that exhibit resistance to antimicrobials is an emergent issue. This article addresses the extent to which clinical antifungal stewardship could influence the scale and epidemiology of resistance to medical antifungals both now and in the future. The importance of uncharted selection pressure exerted by agents outside the clinical setting (agricultural pesticides, industrial xenobiotics, biocides, pharmaceutical waste and others) on environmentally ubiquitous spore-forming molds that are lesserstudied but increasingly responsible for drug-refractory infections is considered.
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Affiliation(s)
- Claire M Hull
- Swansea University, College of Medicine, Institute of Life Science: Microbes & Immunity, SA2 8PP, Wales, UK
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25
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Olarte RA, Horn BW, Singh R, Carbone I. Sexual recombination in Aspergillus tubingensis. Mycologia 2015; 107:307-12. [PMID: 25572097 DOI: 10.3852/14-233] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Aspergillus tubingensis from section Nigri (black Aspergilli) is closely related to A. niger and is used extensively in the industrial production of enzymes and organic acids. We recently discovered sexual reproduction in A. tubingensis, and in this study we demonstrate that the progeny are products of meiosis. Progeny were obtained from six crosses involving five MAT1-1 strains and two MAT1-2 strains. We examined three loci, including mating type (MAT), RNA polymerase II (RPB2) and β-tubulin (BT2), and found that 84% (58/69) of progeny were recombinants. Recombination associated with sexual reproduction in A. tubingensis provides a new option for the genetic improvement of industrial strains for enzyme and organic acid production.
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Affiliation(s)
- Rodrigo A Olarte
- Center for Integrated Fungal Research, Department of Plant Pathology, North Carolina State University, Raleigh, North Carolina 27695
| | - Bruce W Horn
- National Peanut Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Dawson, Georgia 39842
| | - Rakhi Singh
- Center for Integrated Fungal Research, Department of Plant Pathology, North Carolina State University, Raleigh, North Carolina 27695
| | - Ignazio Carbone
- Center for Integrated Fungal Research, Department of Plant Pathology, North Carolina State University, Raleigh, North Carolina 27695
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26
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Frisvad JC. Taxonomy, chemodiversity, and chemoconsistency of Aspergillus, Penicillium, and Talaromyces species. Front Microbiol 2015; 5:773. [PMID: 25628613 PMCID: PMC4290622 DOI: 10.3389/fmicb.2014.00773] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Accepted: 12/17/2014] [Indexed: 11/17/2022] Open
Abstract
Aspergillus, Penicillium, and Talaromyces are among the most chemically inventive of all fungi, producing a wide array of secondary metabolites (exometabolites). The three genera are holophyletic in a cladistic sense and polythetic classes in an anagenetic or functional sense, and contain 344, 354, and 88 species, respectively. New developments in classification, cladification, and nomenclature have meant that the species, series, and sections suggested are natural groups that share many extrolites, including exometabolites, exoproteins, exocarbohydrates, and exolipids in addition to morphological features. The number of exometabolites reported from these species is very large, and genome sequencing projects have shown that a large number of additional exometabolites may be expressed, given the right conditions (“cryptic” gene clusters for exometabolites). The exometabolites are biosynthesized via shikimic acid, tricarboxylic acid cycle members, nucleotides, carbohydrates or as polyketides, non-ribosomal peptides, terpenes, or mixtures of those. The gene clusters coding for these compounds contain genes for the biosynthetic building blocks, the linking of these building blocks, tailoring enzymes, resistance for own products, and exporters. Species within a series or section in Aspergillus, Penicillium, and Talaromyces have many exometabolites in common, seemingly acquired by cladogenesis, but some the gene clusters for autapomorphic exometabolites may have been acquired by horizontal gene transfer. Despite genome sequencing efforts, and the many breakthroughs these will give, it is obvious that epigenetic factors play a large role in evolution and function of chemodiversity, and better methods for characterizing the epigenome are needed. Most of the individual species of the three genera produce a consistent and characteristic profile of exometabolites, but growth medium variations, stimulation by exometabolites from other species, and variations in abiotic intrinsic and extrinsic environmental factors such as pH, temperature, redox potential, and water activity will add significantly to the number of biosynthetic families expressed in anyone species. An example of the shared exometabolites in a natural group such as Aspergillus section Circumdati series Circumdati is that most, but not all species produce penicillic acids, aspyrones, neoaspergillic acids, xanthomegnins, melleins, aspergamides, circumdatins, and ochratoxins, in different combinations.
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Affiliation(s)
- Jens C Frisvad
- Section of Eukaryotic Biotechnology, Department of Systems Biology, Technical University of Denmark Kongens Lyngby, Denmark
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28
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Aspergillus citrinoterreus, a new species of section Terrei isolated from samples of patients with nonhematological predisposing conditions. J Clin Microbiol 2014; 53:611-7. [PMID: 25502530 DOI: 10.1128/jcm.03088-14] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The use of molecular identification techniques has revealed an increasing number of new species within Aspergillus section Terrei. We phenotyped a set of 26 clinical isolates that showed genetic differences from Aspergillus terreus sensu stricto by analyzing sequences from PCR-amplified β-tubulin and calmodulin genes and the internal transcribed spacer region. Since the isolates were phylogenetically and morphologically different from all of the members of Aspergillus section Terrei, they are described here as a new species, Aspergillus citrinoterreus, so named because it produces a diffusible yellowish pigment in agar. A. citrinoterreus isolates were significantly more susceptible to itraconazole, voriconazole, and posaconazole than A. terreus sensu stricto isolates were; in contrast, the amphotericin B MICs for both species were high. A. citrinoterreus was found in clinical samples from patients with proven or probable invasive aspergillosis and colonized patients, none of whom had hematological malignancies as predisposing conditions. However, they did have other underlying conditions such as chronic obstructive pulmonary disease, cirrhosis, and cancer or had received a solid organ transplants and presented not only with invasive pulmonary aspergillosis but also with mediastinitis. A. citrinoterreus isolates were detected for the first time in 2002. In all cases of invasive aspergillosis, A. citrinoterreus was found to be a copathogen, mostly with A. fumigatus.
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Abstract
The genus Aspergillus is one of the most widespread groups of fungi on Earth, comprised of about 300-350 species with very diverse lifestyles. Most species produce asexual propagula (conidia) on conidial heads. Despite their ubiquity, a sexual cycle has not yet been identified for most of the aspergilli. Where sexual reproduction is present, species exhibit either homothallic (self fertile) or heterothallic (obligate outcrossing) breeding systems. A parasexual cycle has also been described in some Aspergillus species. As in other fungi, sexual reproduction is governed by mating-type (MAT) genes, which determine sexual identity and are involved in regulating later stages of sexual development. Previous population genetic studies have indicated that some supposedly asexual aspergilli exhibit evidence of a recombining population structure, suggesting the presence of a cryptic sexual cycle. In addition, genome analyses have revealed networks of genes necessary for sexual reproduction in several Aspergillus species, again consistent with latent sexuality in these fungi. Knowledge of MAT gene presence has then successfully been applied to induce sexual reproduction between MAT1-1 and MAT1-2 isolates of certain supposedly asexual aspergilli. Recent progress in understanding the extent and significance of sexual reproduction is described here, with special emphasis on findings that are relevant to clinically important aspergilli.
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Heitman J, Carter DA, Dyer PS, Soll DR. Sexual reproduction of human fungal pathogens. Cold Spring Harb Perspect Med 2014; 4:4/8/a019281. [PMID: 25085958 DOI: 10.1101/cshperspect.a019281] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
We review here recent advances in our understanding of sexual reproduction in fungal pathogens that commonly infect humans, including Candida albicans, Cryptococcus neoformans/gattii, and Aspergillus fumigatus. Where appropriate or relevant, we introduce findings on other species associated with human infections. In particular, we focus on rapid advances involving genetic, genomic, and population genetic approaches that have reshaped our view of how fungal pathogens evolve. Rather than being asexual, mitotic, and largely clonal, as was thought to be prevalent as recently as a decade ago, we now appreciate that the vast majority of pathogenic fungi have retained extant sexual, or parasexual, cycles. In some examples, sexual and parasexual unions of pathogenic fungi involve closely related individuals, generating diversity in the population but with more restricted recombination than expected from fertile, sexual, outcrossing and recombining populations. In other cases, species and isolates participate in global outcrossing populations with the capacity for considerable levels of gene flow. These findings illustrate general principles of eukaryotic pathogen emergence with relevance for other fungi, parasitic eukaryotic pathogens, and both unicellular and multicellular eukaryotic organisms.
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Affiliation(s)
- Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710
| | - Dee A Carter
- School of Molecular Bioscience, University of Sydney, Sydney NSW 2006, Australia
| | - Paul S Dyer
- School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
| | - David R Soll
- Department of Biology, University of Iowa, Iowa City, Iowa 52242
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Houbraken J, de Vries RP, Samson RA. Modern taxonomy of biotechnologically important Aspergillus and Penicillium species. ADVANCES IN APPLIED MICROBIOLOGY 2014; 86:199-249. [PMID: 24377856 DOI: 10.1016/b978-0-12-800262-9.00004-4] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Taxonomy is a dynamic discipline and name changes of fungi with biotechnological, industrial, or medical importance are often difficult to understand for researchers in the applied field. Species belonging to the genera Aspergillus and Penicillium are commonly used or isolated, and inadequate taxonomy or uncertain nomenclature of these genera can therefore lead to tremendous confusion. Misidentification of strains used in biotechnology can be traced back to (1) recent changes in nomenclature, (2) new taxonomic insights, including description of new species, and/or (3) incorrect identifications. Changes in the recent published International Code of Nomenclature for Algae, Fungi and Plants will lead to numerous name changes of existing Aspergillus and Penicillium species and an overview of the current names of biotechnological important species is given. Furthermore, in (biotechnological) literature old and invalid names are still used, such as Aspergillus awamori, A. foetidus, A. kawachii, Talaromyces emersonii, Acremonium cellulolyticus, and Penicillium funiculosum. An overview of these and other species with their correct names is presented. Furthermore, the biotechnologically important species Talaromyces thermophilus is here combined in Thermomyces as Th. dupontii. The importance of Aspergillus, Penicillium, and related genera is also illustrated by the high number of undertaken genome sequencing projects. A number of these strains are incorrectly identified or atypical strains are selected for these projects. Recommendations for correct strain selection are given here. Phylogenetic analysis shows a close relationship between the genome-sequenced strains of Aspergillus, Penicillium, and Monascus. Talaromyces stipitatus and T. marneffei (syn. Penicillium marneffei) are closely related to Thermomyces lanuginosus and Th. dupontii (syn. Talaromyces thermophilus), and these species appear to be distantly related to Aspergillus and Penicillium. In the last part of this review, an overview of heterothallic reproduction in Aspergillus and Penicillium is given. The new insights in the taxonomy of Aspergillus, Penicillium, and related genera will help to interpret the results generated with comparative genomics studies or other studies dealing with evolution of, for example, enzymes, mating-type loci, virulence genes, and secondary metabolite biosynthetic gene clusters.
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Affiliation(s)
- Jos Houbraken
- CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands.
| | | | - Robert A Samson
- CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands
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Mating type genes and cryptic sexuality as tools for genetically manipulating industrial molds. Appl Microbiol Biotechnol 2013; 97:9609-20. [DOI: 10.1007/s00253-013-5268-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 09/12/2013] [Accepted: 09/14/2013] [Indexed: 01/11/2023]
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Horn BW, Olarte RA, Peterson SW, Carbone I. Sexual reproduction in Aspergillus tubingensis from section Nigri. Mycologia 2013; 105:1153-63. [PMID: 23709489 DOI: 10.3852/13-101] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A sclerotium-forming member of Aspergillus section Nigri was sampled from a population in a single field in North Carolina, USA, and identified as A. tubingensis based on genealogical concordance analysis. Aspergillus tubingensis was shown to be heterothallic, with individual strains containing either a MAT1-1 or MAT1-2 mating-type gene. Strains of opposite mating type were crossed on mixed cereal agar and incubated for 5-6 months. Stromata typically formed 1-2 indehiscent ascocarps containing asci and ascospores within the pseudo-parenchymatous matrix in a manner similar to the Petromyces sexual stage from section Flavi, which is closely related to section Nigri. Ascospores of A. tubingensis differed from those of section Flavi species in the reticulate ornamentation of ascospores and the presence of two crests that form an equatorial furrow. Sexual reproduction in A. tubingensis may be useful for enhancing enzyme and organic acid production through recombination-mediated genetic engineering of industrial strains.
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Affiliation(s)
- Bruce W Horn
- National Peanut Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Dawson, Georgia 39842
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Discovery of a sexual cycle in Aspergillus lentulus, a close relative of A. fumigatus. EUKARYOTIC CELL 2013; 12:962-9. [PMID: 23650087 PMCID: PMC3697472 DOI: 10.1128/ec.00040-13] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Aspergillus lentulus was described in 2005 as a new species within the A. fumigatus sensu lato complex. It is an opportunistic human pathogen causing invasive aspergillosis with high mortality rates, and it has been isolated from clinical and environmental sources. The species is morphologically nearly identical to A. fumigatus sensu stricto, and this similarity has resulted in their frequent misidentification. Comparative studies show that A. lentulus has some distinguishing growth features and decreased in vitro susceptibility to several antifungal agents, including amphotericin B and caspofungin. Similar to the once-presumed-asexual A. fumigatus, it has only been known to reproduce mitotically. However, we now show that A. lentulus has a heterothallic sexual breeding system. A PCR-based mating-type diagnostic detected isolates of either the MAT1-1 or MAT1-2 genotype, and examination of 26 worldwide clinical and environmental isolates revealed similar ratios of the two mating types (38% versus 62%, respectively). MAT1-1 and MAT1-2 idiomorph regions were analyzed, revealing the presence of characteristic alpha and high-mobility-group (HMG) domain genes, together with other more unusual features such as a MAT1-2-4 gene. We then demonstrated that A. lentulus possesses a functional sexual cycle with mature cleistothecia, containing heat-resistant ascospores, being produced after 3 weeks of incubation. Recombination was confirmed using molecular markers. However, isolates of A. lentulus failed to cross with highly fertile strains of A. fumigatus, demonstrating reproductive isolation between these sibling species. The discovery of the A. lentulus sexual stage has significant implications for the management of drug resistance and control of invasive aspergillosis associated with this emerging fungal pathogen.
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Sexual reproduction and mating-type-mediated strain development in the penicillin-producing fungus Penicillium chrysogenum. Proc Natl Acad Sci U S A 2013; 110:1476-81. [PMID: 23307807 DOI: 10.1073/pnas.1217943110] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Penicillium chrysogenum is a filamentous fungus of major medical and historical importance, being the original and present-day industrial source of the antibiotic penicillin. The species has been considered asexual for more than 100 y, and despite concerted efforts, it has not been possible to induce sexual reproduction, which has prevented sexual crosses being used for strain improvement. However, using knowledge of mating-type (MAT) gene organization, we now describe conditions under which a sexual cycle can be induced leading to production of meiotic ascospores. Evidence of recombination was obtained using both molecular and phenotypic markers. The identified heterothallic sexual cycle was used for strain development purposes, generating offspring with novel combinations of traits relevant to penicillin production. Furthermore, the MAT1-1-1 mating-type gene, known primarily for a role in governing sexual identity, was also found to control transcription of a wide range of genes with biotechnological relevance including those regulating penicillin production, hyphal morphology, and conidial formation. These discoveries of a sexual cycle and MAT gene function are likely to be of broad relevance for manipulation of other asexual fungi of economic importance.
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