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Katati B, Kovács S, Njapau H, Kachapulula PW, Zwaan BJ, van Diepeningen AD, Schoustra SE. Maize Aspergillus section Flavi isolate diversity may be distinct from that of soil and subsequently the source of aflatoxin contamination. Mycotoxin Res 2024; 40:351-367. [PMID: 38647834 PMCID: PMC11258066 DOI: 10.1007/s12550-024-00532-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 03/17/2024] [Accepted: 03/20/2024] [Indexed: 04/25/2024]
Abstract
Aspergillus section Flavi (Flavi) is a diverse group of fungal species whose common members include A. flavus and A. parasiticus. These are well-known for the production of aflatoxin (AF) B and G and other toxic metabolites, like cyclopiazonic acid (CPA). They are saprophytic soil dwellers and also become crop opportunistic epiphytes. The consequence is contamination of the crop with mycotoxins, such as carcinogenic AF. We investigated the Flavi community structure of maize and that of their surrounding soil, including their mycotoxigenicity. Furthermore, we investigated the link of the maize Flavi diversity with preharvest maize AF levels. The study was carried out in four selected districts of Zambia, in a low rainfall zone. The Flavi characterisation was triphasic, involving morphological (colony colour and sclerotia formation), metabolic (AF and CPA production) and genetic (calmodulin gene polymorphism) analyses. Flavi abundance was determined by dilution plate technique on modified rose Bengal agar. Results showed that Flavi communities on maize and in soil differed. Maize had a higher Flavi species diversity than soil. A. parasiticus dominated the soil community by frequency of field appearance (85%), while maize was dominated by A. minisclerotigenes (45%). CPA-producers with or without AF production dominated the maize (65%) while producers of only AF (B/G) dominated the soil (88%). The ratio between maize A. parasiticus and A. minisclerotigenes abundance seemed to have had a bearing on the levels of AF in maize, with a ratio close to 1:1 having higher levels than a pure community of either A. parasiticus or A. minisclerotigenes.
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Affiliation(s)
- Bwalya Katati
- Laboratory of Genetics, Wageningen University and Research, Wageningen, The Netherlands.
- Mycotoxicology Laboratory, National Institute for Scientific and Industrial Research, Lusaka, Zambia.
| | - Stan Kovács
- Laboratory of Genetics, Wageningen University and Research, Wageningen, The Netherlands
| | - Henry Njapau
- Mycotoxicology Laboratory, National Institute for Scientific and Industrial Research, Lusaka, Zambia
| | | | - Bas J Zwaan
- Laboratory of Genetics, Wageningen University and Research, Wageningen, The Netherlands
| | - Anne D van Diepeningen
- Biointeractions and Plant Health, Wageningen University and Research, Wageningen, The Netherlands
| | - Sijmen E Schoustra
- Laboratory of Genetics, Wageningen University and Research, Wageningen, The Netherlands
- School of Agricultural Sciences, University of Zambia, Lusaka, Zambia
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2
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Shen X, Lei C, Zhang A, Wang L, Chen D, Qi L, Hu Y, Chen G, Ran H, Yin WB. Stimulating Novel and Bioactive Metabolite Production by Cocultivation of Two Fungi ─Aspergillus oryzae and Epicoccum dendrobii. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024. [PMID: 39020512 DOI: 10.1021/acs.jafc.4c04764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2024]
Abstract
Fungi produce various bioactive secondary metabolites (SMs) as protective and weaponized tools to enhance survival in shared ecological niches. By mimicking a competitive ecosystem, cocultivation has been proven to be particularly successful in stimulating SM discovery. Here, we reported the identification of four novel metabolites, epiclactones A and B, epioxochromane and aoergostane, from the coculture of two biotechnologically important strains, Aspergillus oryzae and Epicoccum dendrobii. Transcriptome and metabolome analyses revealed widespread silent gene activation during fungal-fungal interaction. The majority of differentially expressed gene clusters were summarized for both strains. Based on these highly activated biosynthetic pathways, we suggested that a bidirectional chemical defense occurred under cocultivation. E. dendrobii enhanced the production of the spore inhibitor, fumigermin. Moreover, A. oryzae highly accumulated the antifungal agent kojic acid with a yield of up to 1.10 g/L. This study provides an excellent example for the discovery of hidden natural products by cocultivation.
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Affiliation(s)
- Xiangrui Shen
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, PR China
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Chengzhi Lei
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
- Medical School, University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Anxin Zhang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Long Wang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Denghui Chen
- Henan Academy of Science Institute of Biology, Zhengzhou 450008, PR China
| | - Landa Qi
- Henan Academy of Science Institute of Biology, Zhengzhou 450008, PR China
| | - Yiliang Hu
- Henan Academy of Science Institute of Biology, Zhengzhou 450008, PR China
| | - Guocan Chen
- Henan Academy of Science Institute of Biology, Zhengzhou 450008, PR China
| | - Huomiao Ran
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
- Henan Academy of Science Institute of Biology, Zhengzhou 450008, PR China
| | - Wen-Bing Yin
- School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, PR China
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
- Medical School, University of Chinese Academy of Sciences, Beijing 100049, PR China
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Luciano-Rosario D, Jurick WM, Gottschalk C. The Near-Gapless Penicillium fuscoglaucum Genome Enables the Discovery of Lifestyle Features as an Emerging Post-Harvest Phytopathogen. J Fungi (Basel) 2024; 10:430. [PMID: 38921416 PMCID: PMC11204653 DOI: 10.3390/jof10060430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 05/28/2024] [Accepted: 06/03/2024] [Indexed: 06/27/2024] Open
Abstract
Penicillium spp. occupy many diverse biological niches that include plant pathogens, opportunistic human pathogens, saprophytes, indoor air contaminants, and those selected specifically for industrial applications to produce secondary metabolites and lifesaving antibiotics. Recent phylogenetic studies have established Penicillium fuscoglaucum as a synonym for Penicillium commune, which is an indoor air contaminant and toxin producer and can infect apple fruit during storage. During routine culturing on selective media in the lab, we obtained an isolate of P. fuscoglaucum Pf_T2 and sequenced its genome. The Pf_T2 genome is far superior to available genomic resources for the species. Our assembly exhibits a length of 35.1 Mb, a BUSCO score of 97.9% complete, and consists of five scaffolds/contigs representing the four expected chromosomes. It was determined that the Pf_T2 genome was colinear with a type specimen P. fuscoglaucum and contained a lineage-specific, intact cyclopiazonic acid (CPA) gene cluster. For comparison, a highly virulent postharvest apple pathogen, P. expansum strain TDL 12.1, was included and showed a similar growth pattern in culture to our Pf_T2 isolate but was far more aggressive in apple fruit than P. fuscoglaucum. The genome of Pf_T2 serves as a major improvement over existing resources, has superior annotation, and can inform forthcoming omics-based work and functional genetic studies to probe secondary metabolite production and disparities in aggressiveness during apple fruit decay.
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Affiliation(s)
- Dianiris Luciano-Rosario
- Food Quality Laboratory, USDA-ARS, Beltsville, MD 20705, USA;
- ORISE Postdoctoral Research Fellow, Oak Ridge, TN 37830, USA
| | - Wayne M. Jurick
- Food Quality Laboratory, USDA-ARS, Beltsville, MD 20705, USA;
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Chang PK. Creating large chromosomal segment deletions in Aspergillus flavus by a dual CRISPR/Cas9 system: Deletion of gene clusters for production of aflatoxin, cyclopiazonic acid, and ustiloxin B. Fungal Genet Biol 2024; 170:103863. [PMID: 38154756 DOI: 10.1016/j.fgb.2023.103863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 12/21/2023] [Accepted: 12/26/2023] [Indexed: 12/30/2023]
Abstract
Aspergillus flavus produces hepatocarcinogenic aflatoxin that adversely impacts human and animal health and international trade. A promising means to manage preharvest aflatoxin contamination of crops is biological control, which employs non-aflatoxigenic A. flavus isolates possessing defective aflatoxin gene clusters to outcompete field toxigenic populations. However, these isolates often produce other toxic metabolites. The CRISPR/Cas9 technology has greatly advanced genome editing and gene functional studies. Its use in deleting large chromosomal segments of filamentous fungi is rarely reported. A system of dual CRISPR/Cas9 combined with a 60-nucleotide donor DNA that allowed removal of A. flavus gene clusters involved in production of harmful specialized metabolites was established. It efficiently deleted a 102-kb segment containing both aflatoxin and cyclopiazonic acid gene clusters from toxigenic A. flavus morphotypes, L-type and S-type. It further deleted the 27-kb ustiloxin B gene cluster of a resulting L-type mutant. Overall efficiencies of deletion ranged from 66.6 % to 85.6 % and efficiencies of deletions repaired by a single copy of donor DNA ranged from 50.5 % to 72.7 %. To determine the capacity of this technique, a pigment-screening setup based on absence of aspergillic acid gene cluster was devised. Chromosomal segments of 201 kb and 301 kb were deleted with efficiencies of 57.7 % to 69.2 %, respectively. This system used natural A. flavus isolates as recipients, eliminated a forced-recycling step to produce recipients for next round deletion, and generated maker-free deletants with sequences predefined by donor DNA. The research provides a method for creating genuine atoxigenic biocontrol strains friendly for field trial release.
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Affiliation(s)
- Perng-Kuang Chang
- Southern Regional Research Center, Agricultural Research Service, U. S. Department of Agriculture, 1100 Allen Toussaint Boulevard, New Orleans, LA 70124, United States.
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Zhang W, Jiang X, Wang M, Zhang Z, Wang N. Origin of the 6/5/6/5 Tetracyclic Cyclopiazonic Acids. Mar Drugs 2024; 22:74. [PMID: 38393045 PMCID: PMC10890092 DOI: 10.3390/md22020074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 01/29/2024] [Accepted: 01/29/2024] [Indexed: 02/25/2024] Open
Abstract
The natural product α-cyclopiazonic acid (α-CPA) is a very potent Ca2+-ATPase inhibitor. The CPA family of compounds comprise over 80 chemical entities with at least five distinct skeletons. While α-CPA features a canonical 6/5/6/5/5 skeleton, the 6/5/6/5 skeleton is the most prevalent among the CPA family. However, the origin of the unique tetracyclic skeleton remains unknown. The 6/5/6/5-type CPAs may derive from a precursor of acetoacetyl-l-tryptophan (AATrp) generated from a hypothetic thioesterase-like pathway. Alternatively, cleavage of the tetramic acid ring would also result in the formation of the 6/5/6/5 scaffold. Aspergillus oryzae HMP-F28 is a marine sponge-associated filamentous fungus known to produce CPAs that act as primary neurotoxins. To elucidate the origin of this subfamily of CPAs, we performed homologous recombination and genetic engineering experiments on strain HMP-F28. Our results are supportive of the ring cleavage pathway through which the tetracyclic 6/5/6/5-type CPAs are generated from 6/5/6/5/5-type pentacyclic CPAs.
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Affiliation(s)
- Wenyuan Zhang
- Ocean College, Zhejiang University, Zhoushan 316021, China
| | - Xuejian Jiang
- Ocean College, Zhejiang University, Zhoushan 316021, China
| | - Minjun Wang
- Ocean College, Zhejiang University, Zhoushan 316021, China
| | - Zhizhen Zhang
- Ocean College, Zhejiang University, Zhoushan 316021, China
| | - Nan Wang
- Ocean College, Zhejiang University, Zhoushan 316021, China
- Hainan Institute of Zhejiang University, Sanya 572025, China
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Arreguin-Perez CA, Miranda-Miranda E, Folch-Mallol JL, Cossío-Bayúgar R. Identification of Virulence Factors in Entomopathogenic Aspergillus flavus Isolated from Naturally Infected Rhipicephalus microplus. Microorganisms 2023; 11:2107. [PMID: 37630667 PMCID: PMC10457961 DOI: 10.3390/microorganisms11082107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 08/10/2023] [Accepted: 08/15/2023] [Indexed: 08/27/2023] Open
Abstract
Aspergillus flavus has been found to be an effective entomopathogenic fungus for various arthropods, including ticks. In particular, natural fungal infections in cattle ticks show promise for biocontrol of the Rhipicephalus (Boophilus) microplus tick, which is a major ectoparasite affecting cattle worldwide. Our study aimed to elucidate the specific entomopathogenic virulence factors encoded in the genome of an A. flavus strain isolated from naturally infected cattle ticks. We performed morphological and biochemical phenotyping alongside complete genome sequencing, which revealed that the isolated fungus was A. flavus related to the L morphotype, capable of producing a range of gene-coded entomopathogenic virulence factors, including ribotoxin, aflatoxin, kojic acid, chitinases, killer toxin, and satratoxin. To evaluate the efficacy of this A. flavus strain against ticks, we conducted experimental bioassays using healthy engorged female ticks. A morbidity rate of 90% was observed, starting at a concentration of 105 conidia/mL. At a concentration of 107 conidia/mL, we observed a 50% mortality rate and a 21.5% inhibition of oviposition. The highest levels of hatch inhibition (30.8%) and estimated reproduction inhibition (34.64%) were achieved at a concentration of 108 conidia/mL. Furthermore, the tick larval progeny that hatched from the infected tick egg masses showed evident symptoms of Aspergillus infection after incubation.
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Affiliation(s)
- Cesar A. Arreguin-Perez
- Centro Nacional de Investigación Disciplinaria en Salud Animal e Inocuidad, Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias INIFAP, Boulevard Cuauhnahuac 8534, Jiutepec 62574, Morelos, Mexico; (C.A.A.-P.); (E.M.-M.)
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Cuernavaca 62209, Morelos, Mexico;
| | - Estefan Miranda-Miranda
- Centro Nacional de Investigación Disciplinaria en Salud Animal e Inocuidad, Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias INIFAP, Boulevard Cuauhnahuac 8534, Jiutepec 62574, Morelos, Mexico; (C.A.A.-P.); (E.M.-M.)
| | - Jorge Luis Folch-Mallol
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Cuernavaca 62209, Morelos, Mexico;
| | - Raquel Cossío-Bayúgar
- Centro Nacional de Investigación Disciplinaria en Salud Animal e Inocuidad, Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias INIFAP, Boulevard Cuauhnahuac 8534, Jiutepec 62574, Morelos, Mexico; (C.A.A.-P.); (E.M.-M.)
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7
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Malir F, Pickova D, Toman J, Grosse Y, Ostry V. Hazard characterisation for significant mycotoxins in food. Mycotoxin Res 2023; 39:81-93. [PMID: 36930431 DOI: 10.1007/s12550-023-00478-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 02/16/2023] [Accepted: 02/17/2023] [Indexed: 03/18/2023]
Abstract
This review updates the current status of activities related to hazard characterisation for mycotoxins, with special reference to regulatory work accomplished within the European Union. Because the relevant information on these topics is widely scattered in the scientific literature, this review intends to provide a condensed overview on the most pertinent aspects. Human health risk assessment is a procedure to estimate the nature and potential for harmful effects of mycotoxins on human health due to exposure to them via contaminated food. This assessment involves hazard identification, hazard characterisation, exposure assessment, and risk characterisation. Mycotoxins covered in this review are aflatoxins, ochratoxin A, cyclopiazonic acid, citrinin, trichothecenes (deoxynivalenol, nivalenol, T-2, and HT-2 toxins), fumonisins, zearalenone, patulin, and ergot alkaloids. For mycotoxins with clear genotoxic/carcinogenic properties, the focus is on the margin of exposure approach. One of its goals is to document predictive characterisation of the human hazard, based on studies in animals using conditions of low exposure. For the other, non-genotoxic toxins, individual 'no adverse effect levels' have been established, but structural analogues or modified forms may still complicate assessment. During the process of hazard characterisation, each identified effect is assessed for human relevance. The estimation of a 'safe dose' is the hazard characterisation endpoint. The final aim of all of these activities is to establish a system, which is able to minimise and control the risk for the consumer from mycotoxins in food. Ongoing research on mycotoxins constantly comes up with new findings, which may have to be implemented into this system.
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Affiliation(s)
- Frantisek Malir
- Department of Biology, Faculty of Science, University of Hradec Kralove, Rokitanskeho 62, CZ-50003, Hradec Kralove, Czech Republic.
| | - Darina Pickova
- Department of Biology, Faculty of Science, University of Hradec Kralove, Rokitanskeho 62, CZ-50003, Hradec Kralove, Czech Republic
| | - Jakub Toman
- Department of Biology, Faculty of Science, University of Hradec Kralove, Rokitanskeho 62, CZ-50003, Hradec Kralove, Czech Republic
| | - Yann Grosse
- The IARC Monographs Programme, International Agency for Research On Cancer (retired), Lyon, France
| | - Vladimir Ostry
- Center for Health, Nutrition and Food in Brno, National Institute of Public Health, Palackeho 3a, 61242, Brno, Czech Republic
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8
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Maragos CM, Probyn C, Proctor RH, Sieve KK. Cyclopiazonic acid in soft-ripened and blue cheeses marketed in the USA. FOOD ADDITIVES & CONTAMINANTS. PART B, SURVEILLANCE 2023; 16:14-23. [PMID: 35997046 DOI: 10.1080/19393210.2022.2109213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Strains of Penicillium camemberti and P. roqueforti are used in the production of soft-ripened and blue-veined cheeses. However, some strains can produce toxic secondary metabolites (mycotoxins), including α-cyclopiazonic acid (CPA), a neurotoxin. Data on the levels of CPA in cheeses marketed in the USA are extremely limited. An enzyme-linked immunosorbent assay was adapted for measuring CPA in soft-ripened and blue-veined cheeses. Recoveries from cheese curds were 103 ± 27% (n = 30). A total of 254 samples of soft-ripened, blue and miscellaneous cheeses were examined. CPA was detected in 36/79 (45.6%) of soft-ripened cheeses and in 41/168 (24.4%) of blue-veined cheeses. Median levels in positive samples were 48.5 µg/kg and 30 µg/kg, respectively. The highest levels found were 3,820 µg/kg (in a Brie), 1,250 µg/kg (in a blue) and 7,900 µg/kg (in a Monte Enebro). The implication of such exposures is unknown, as a consensus on acceptable intake remains to be established.
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Affiliation(s)
- Chris M Maragos
- Mycotoxin Prevention and Applied Microbiology Research Unit, USDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, Illinois, USA
| | - Crystal Probyn
- Mycotoxin Prevention and Applied Microbiology Research Unit, USDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, Illinois, USA
| | - Robert H Proctor
- Mycotoxin Prevention and Applied Microbiology Research Unit, USDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, Illinois, USA
| | - Kristal K Sieve
- Mycotoxin Prevention and Applied Microbiology Research Unit, USDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, Illinois, USA
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Walsh CT. Tailoring enzyme strategies and functional groups in biosynthetic pathways. Nat Prod Rep 2023; 40:326-386. [PMID: 36268810 DOI: 10.1039/d2np00048b] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Covering: 2000 to 2022Secondary metabolites are assembled by drawing off and committing some of the flux of primary metabolic building blocks to sets of enzymes that tailor the maturing scaffold to increase architectural and framework complexity, often balancing hydrophilic and hydrophobic surfaces. In this review we examine the small number of chemical strategies that tailoring enzymes employ in maturation of scaffolds. These strategies depend both on the organic functional groups present at each metabolic stage and one of two tailoring enzyme strategies. Nonoxidative tailoring enzymes typically transfer electrophilic fragments, acyl, alkyl and glycosyl groups, from a small set of thermodynamically activated but kinetically stable core metabolites. Oxidative tailoring enzymes can be oxygen-independent or oxygen-dependent. The oxygen independent oxidoreductases are often reversible nicotinamide-utilizing redox catalysts, flipping the nucleophilicity and electrophilicity of functional groups in pathway intermediates. O2-dependent oxygenases, both mono- and dioxygenases, act by orthogonal, one electron strategies, generating carbon radical species. At sp3 substrate carbons, product alcohols may then behave as nucleophiles for subsequent waves of enzymatic tailoring. At sp2 carbons in olefins, electrophilic epoxides have opposite reactivity and often function as "disappearing groups", opened by intramolecular nucleophiles during metabolite maturation. "Thwarted" oxygenases generate radical intermediates that rearrange internally and are not captured oxygenatively.
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Kubisch C, Kövilein A, Aliyu H, Ochsenreither K. RNA-Seq Based Transcriptome Analysis of Aspergillus oryzae DSM 1863 Grown on Glucose, Acetate and an Aqueous Condensate from the Fast Pyrolysis of Wheat Straw. J Fungi (Basel) 2022; 8:jof8080765. [PMID: 35893132 PMCID: PMC9394295 DOI: 10.3390/jof8080765] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 11/16/2022] Open
Abstract
Due to its acetate content, the pyrolytic aqueous condensate (PAC) formed during the fast pyrolysis of wheat straw could provide an inexpensive substrate for microbial fermentation. However, PAC also contains several inhibitors that make its detoxification inevitable. In our study, we examined the transcriptional response of Aspergillus oryzae to cultivation on 20% detoxified PAC, pure acetate and glucose using RNA-seq analysis. Functional enrichment analysis of 3463 significantly differentially expressed (log2FC >2 & FDR < 0.05) genes revealed similar metabolic tendencies for both acetate and PAC, as upregulated genes in these cultures were mainly associated with ribosomes and RNA processing, whereas transmembrane transport was downregulated. Unsurprisingly, metabolic pathway analysis revealed that glycolysis/gluconeogenesis and starch and sucrose metabolism were upregulated for glucose, whereas glyoxylate and the tricarboxylic acid (TCA) cycle were important carbon utilization pathways for acetate and PAC, respectively. Moreover, genes involved in the biosynthesis of various amino acids such as arginine, serine, cysteine and tryptophan showed higher expression in the acetate-containing cultures. Direct comparison of the transcriptome profiles of acetate and PAC revealed that pyruvate metabolism was the only significantly different metabolic pathway and was overexpressed in the PAC cultures. Upregulated genes included those for methylglyoxal degradation and alcohol dehydrogenases, which thus represent potential targets for the further improvement of fungal PAC tolerance.
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Deepika C, Hariprasanna K, Das IK, Jacob J, Ronanki S, Ratnavathi CV, Bellundagi A, Sooganna D, Tonapi VA. 'Kodo poisoning': cause, science and management. JOURNAL OF FOOD SCIENCE AND TECHNOLOGY 2022; 59:2517-2526. [PMID: 35734115 PMCID: PMC9206982 DOI: 10.1007/s13197-021-05141-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 04/03/2021] [Accepted: 05/12/2021] [Indexed: 06/15/2023]
Abstract
Many mycotoxigenic fungi infect the food crops and affect the quality of the produce due to production of mycotoxins. Kodo millet is one of the important minor millets cultivated in India, mostly confined to marginal lands and tribal regions but has high yield potential under good management. The grains are nutritious and have anti-oxidant properties besides having many medicinal properties. However, the consumption is often hindered by the condition called 'kodo poisoning' resulting from fungal contamination producing cyclopiazonic acid, a toxic fungal secondary metabolite. An attempt has been made here to review the limited information available on kodo poisoning, its causes and effects, and proposed management practices by which the contamination can be checked. Further research efforts are essential for identifying sources of natural resistance to fungal metabolite, induction of host resistance through antimicrobial compounds or microbial antagonism to the pathogens to achieve cleaner grains from this crop even under high humid and rainy conditions. By effective adoption of both pre- and post-harvest management the kodo millet grains can be made safe for human consumption and can be popularized as a nutritious grain.
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Affiliation(s)
- C. Deepika
- ICAR-Indian Institute of Millets Research, Rajendranagar, Hyderabad, 500030 India
| | - K. Hariprasanna
- ICAR-Indian Institute of Millets Research, Rajendranagar, Hyderabad, 500030 India
| | - I. K. Das
- ICAR-Indian Institute of Millets Research, Rajendranagar, Hyderabad, 500030 India
| | - Jinu Jacob
- ICAR-Indian Institute of Millets Research, Rajendranagar, Hyderabad, 500030 India
| | - Swarna Ronanki
- ICAR-Indian Institute of Millets Research, Rajendranagar, Hyderabad, 500030 India
| | - C. V. Ratnavathi
- ICAR-Indian Institute of Millets Research, Rajendranagar, Hyderabad, 500030 India
| | - Amasiddha Bellundagi
- ICAR-Indian Institute of Millets Research, Rajendranagar, Hyderabad, 500030 India
| | - D. Sooganna
- ICAR-Indian Institute of Millets Research, Rajendranagar, Hyderabad, 500030 India
| | - Vilas A. Tonapi
- ICAR-Indian Institute of Millets Research, Rajendranagar, Hyderabad, 500030 India
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Xie H, Wang X, van der Hooft JJ, Medema MH, Chen ZY, Yue X, Zhang Q, Li P. Fungi population metabolomics and molecular network study reveal novel biomarkers for early detection of aflatoxigenic Aspergillus species. JOURNAL OF HAZARDOUS MATERIALS 2022; 424:127173. [PMID: 34597924 DOI: 10.1016/j.jhazmat.2021.127173] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 09/04/2021] [Accepted: 09/06/2021] [Indexed: 06/13/2023]
Abstract
Mycotoxins threaten global food safety, public health and cause huge socioeconomic losses. Early detection is an effective preventive strategy, yet efficient biomarkers for early detection of aflatoxigenic Aspergillus species are lacking. Here, we proposed to use untargeted metabolomics and machine learning to mine biomarkers of aflatoxigenic Aspergillus species. We systematically delineated metabolic differences across 568 extensive field sampling A. flavus and performed biomarker analysis. Versicolorin B, 11-hydroxy-O-methylsterigmatocystin et.al metabolites shown a high correlation (from 0.71 to 0.95) with strains aflatoxin-producing capacity. Molecular networking analysis deciphered the connection of aflatoxins and biomarkers as well as potential emerging mycotoxins. We then developed a model using the biomarkers as variables to discern aflatoxigenic Aspergillus species with 97.8% accuracy. A validation dataset and metabolome from other 16 fungal isolates confirmed the robustness and specificity of these biomarkers. We further demonstrated the solution feasibility in agricultural products by early detection of biomarkers, which predicted aflatoxin contamination risk 35-47 days in advance. A developed operable decision rule by the XGBoost algorithm help regulators to intuitively assess the risk prioritization with 87.2% accuracy. Our research provides novel insights into global food safety risk assessment which will be crucial for early prevention and control of mycotoxins.
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Affiliation(s)
- Huali Xie
- Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan 430061, China; Key laboratory of Detection for Aflatoxins, Ministry of Agriculture, Wuhan, China; Laboratory of Risk Assessment for Oilseeds Products (Wuhan), Ministry of Agriculture, Wuhan 430061, China; Bioinformatics Group, Wageningen University, 6708PB Wageningen, The Netherlands
| | - Xiupin Wang
- Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan 430061, China; Laboratory of Risk Assessment for Oilseeds Products (Wuhan), Ministry of Agriculture, Wuhan 430061, China; Quality Inspection and Test Center for Oilseeds Products, Ministry of Agriculture, Wuhan 430061, China
| | | | - Marnix H Medema
- Bioinformatics Group, Wageningen University, 6708PB Wageningen, The Netherlands
| | - Zhi-Yuan Chen
- Department of Plant Pathology and Crop Physiology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA
| | - Xiaofeng Yue
- Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan 430061, China; Laboratory of Risk Assessment for Oilseeds Products (Wuhan), Ministry of Agriculture, Wuhan 430061, China
| | - Qi Zhang
- Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan 430061, China; Key laboratory of Detection for Aflatoxins, Ministry of Agriculture, Wuhan, China; Laboratory of Risk Assessment for Oilseeds Products (Wuhan), Ministry of Agriculture, Wuhan 430061, China; Quality Inspection and Test Center for Oilseeds Products, Ministry of Agriculture, Wuhan 430061, China; Hubei Hongshan Laboratory, Wuhan, China.
| | - Peiwu Li
- Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan 430061, China; Key laboratory of Detection for Aflatoxins, Ministry of Agriculture, Wuhan, China; Laboratory of Risk Assessment for Oilseeds Products (Wuhan), Ministry of Agriculture, Wuhan 430061, China; Quality Inspection and Test Center for Oilseeds Products, Ministry of Agriculture, Wuhan 430061, China; Hubei Hongshan Laboratory, Wuhan, China.
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13
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Costes LH, Lippi Y, Naylies C, Jamin EL, Genthon C, Bailly S, Oswald IP, Bailly JD, Puel O. The Solvent Dimethyl Sulfoxide Affects Physiology, Transcriptome and Secondary Metabolism of Aspergillus flavus. J Fungi (Basel) 2021; 7:jof7121055. [PMID: 34947037 PMCID: PMC8703953 DOI: 10.3390/jof7121055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/30/2021] [Accepted: 12/07/2021] [Indexed: 12/13/2022] Open
Abstract
Dimethyl sulfoxide (DSMO) is a simple molecule widely used because of its great solvating ability, but this solvent also has little-known biological effects, especially on fungi. Aspergillus flavus is a notorious pathogenic fungus which may contaminate a large variety of crops worldwide by producing aflatoxins, endangering at the same time food safety and international trade. The aim of this study was to characterize the effect of DMSO on A. flavus including developmental parameters such as germination and sporulation, as well as its transcriptome profile using high-throughput RNA-sequencing assay and its impact on secondary metabolism (SM). After DMSO exposure, A. flavus displayed depigmented conidia in a dose-dependent manner. The four-day exposition of cultures to two doses of DMSO, chosen on the basis of depigmentation intensity (35 mM “low” and 282 mM “high”), led to no significant impact on fungal growth, germination or sporulation. However, transcriptomic data analysis showed that 4891 genes were differentially regulated in response to DMSO (46% of studied transcripts). A total of 4650 genes were specifically regulated in response to the highest dose of DMSO, while only 19 genes were modulated upon exposure to the lowest dose. Secondary metabolites clusters genes were widely affected by the DMSO, with 91% of clusters impacted at the highest dose. Among these, aflatoxins, cyclopiazonic acid and ustiloxin B clusters were totally under-expressed. The genes belonging to the AFB1 cluster were the most negatively modulated ones, the two doses leading to 63% and 100% inhibition of the AFB1 production, respectively. The SM analysis also showed the disappearance of ustiloxin B and a 10-fold reduction of cyclopiazonic acid level when A. flavus was treated by the higher DMSO dose. In conclusion, the present study showed that DMSO impacted widely A. flavus’ transcriptome, including secondary metabolism gene clusters with the aflatoxins at the head of down-regulated ones. The solvent also inhibits conidial pigmentation, which could illustrate common regulatory mechanisms between aflatoxins and fungal pigment pathways. Because of its effect on major metabolites synthesis, DMSO should not be used as solvent especially in studies testing anti-aflatoxinogenic compounds.
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Affiliation(s)
- Laura H. Costes
- TOXALIM (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, EI-Purpan, Toulouse 31027, France; (L.H.C.); (Y.L.); (C.N.); (E.L.J.); (S.B.); (I.P.O.); (O.P.)
| | - Yannick Lippi
- TOXALIM (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, EI-Purpan, Toulouse 31027, France; (L.H.C.); (Y.L.); (C.N.); (E.L.J.); (S.B.); (I.P.O.); (O.P.)
| | - Claire Naylies
- TOXALIM (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, EI-Purpan, Toulouse 31027, France; (L.H.C.); (Y.L.); (C.N.); (E.L.J.); (S.B.); (I.P.O.); (O.P.)
| | - Emilien L. Jamin
- TOXALIM (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, EI-Purpan, Toulouse 31027, France; (L.H.C.); (Y.L.); (C.N.); (E.L.J.); (S.B.); (I.P.O.); (O.P.)
- Metatoul-AXIOM Platform, MetaboHUB, National Infrastructure for Metabolomics and Fluxomics, Toulouse 31000, France
| | - Clémence Genthon
- INRAE, US1426, GeT-PlaGe, Genotoul, 31326 Castanet-Tolosan, France;
| | - Sylviane Bailly
- TOXALIM (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, EI-Purpan, Toulouse 31027, France; (L.H.C.); (Y.L.); (C.N.); (E.L.J.); (S.B.); (I.P.O.); (O.P.)
| | - Isabelle P. Oswald
- TOXALIM (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, EI-Purpan, Toulouse 31027, France; (L.H.C.); (Y.L.); (C.N.); (E.L.J.); (S.B.); (I.P.O.); (O.P.)
| | - Jean-Denis Bailly
- TOXALIM (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, EI-Purpan, Toulouse 31027, France; (L.H.C.); (Y.L.); (C.N.); (E.L.J.); (S.B.); (I.P.O.); (O.P.)
- Correspondence:
| | - Olivier Puel
- TOXALIM (Research Center in Food Toxicology), Université de Toulouse, INRAE, ENVT, EI-Purpan, Toulouse 31027, France; (L.H.C.); (Y.L.); (C.N.); (E.L.J.); (S.B.); (I.P.O.); (O.P.)
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14
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Nguyen VT, Yu NH, Lee Y, Hwang IM, Bui HX, Kim JC. Nematicidal Activity of Cyclopiazonic Acid Derived From Penicillium commune Against Root-Knot Nematodes and Optimization of the Culture Fermentation Process. Front Microbiol 2021; 12:726504. [PMID: 34899622 PMCID: PMC8651706 DOI: 10.3389/fmicb.2021.726504] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 10/22/2021] [Indexed: 11/24/2022] Open
Abstract
Among 200 fungal strains isolated from the soil, only one culture filtrate of Aspergillus flavus JCK-4087 showed strong nematicidal activity against Meloidogyne incognita. The nematicidal metabolite isolated from the culture filtrate of JCK-4087 was identified as cyclopiazonic acid (CPA). Because JCK-4087 also produced aflatoxins, six strains of Penicillium commune, which have been reported to be CPA producers, were obtained from the bank and then tested for their CPA productivity. CPA was isolated from the culture filtrate of P. commune KACC 45973. CPA killed the second-stage juveniles of M. incognita, M. hapla, and M. arearia with EC50-3 days 4.50, 18.82, and 60.51 μg mL-1, respectively. CPA also significantly inhibited egg hatch of M. incognita and M. hapla after a total of 28 days of treatment with the concentrations > 25 μg mL-1. The enhancement of CPA production by P. commune KACC 45973 was explored using an optimized medium based on Plackett-Burman design (PBD) and central composite design (CCD). The highest CPA production (381.48 μg mL-1) was obtained from the optimized medium, exhibiting an increase of 7.88 times when compared with that from potato dextrose broth culture. Application of the wettable power-type formulation of the ethyl acetate extract of the culture filtrate of KACC 45973 reduced gall formation and nematode populations in tomato roots and soils under greenhouse conditions. These results suggest that CPA produced by P. commune KACC 45973 can be used as either a biochemical nematicide or a lead molecule for developing chemical nematicides to control root-knot nematodes.
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Affiliation(s)
- Van Thi Nguyen
- Department of Agricultural Chemistry, College of Agriculture and Life Sciences, Institute of Environmentally Friendly Agriculture, Chonnam National University, Gwangju, South Korea
| | - Nan Hee Yu
- Department of Agricultural Chemistry, College of Agriculture and Life Sciences, Institute of Environmentally Friendly Agriculture, Chonnam National University, Gwangju, South Korea
| | - Yookyung Lee
- Department of Agricultural Chemistry, College of Agriculture and Life Sciences, Institute of Environmentally Friendly Agriculture, Chonnam National University, Gwangju, South Korea
| | - In Min Hwang
- Hygienic Safety and Analysis Center, World Institute of Kimchi, Gwangju, South Korea
| | - Hung Xuan Bui
- Department of Entomology and Nematology, Gulf Coast Research and Education Center, University of Florida, Wimauma, FL, United States
| | - Jin-Cheol Kim
- Department of Agricultural Chemistry, College of Agriculture and Life Sciences, Institute of Environmentally Friendly Agriculture, Chonnam National University, Gwangju, South Korea
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15
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Mamo FT, Abate BA, Zheng Y, Nie C, He M, Liu Y. Distribution of Aspergillus Fungi and Recent Aflatoxin Reports, Health Risks, and Advances in Developments of Biological Mitigation Strategies in China. Toxins (Basel) 2021; 13:678. [PMID: 34678973 PMCID: PMC8541519 DOI: 10.3390/toxins13100678] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/15/2021] [Accepted: 09/20/2021] [Indexed: 12/24/2022] Open
Abstract
Aflatoxins (AFs) are secondary metabolites that represent serious threats to human and animal health. They are mainly produced by strains of the saprophytic fungus Aspergillus flavus, which are abundantly distributed across agricultural commodities. AF contamination is receiving increasing attention by researchers, food producers, and policy makers in China, and several interesting review papers have been published, that mainly focused on occurrences of AFs in agricultural commodities in China. The goal of this review is to provide a wider scale and up-to-date overview of AF occurrences in different agricultural products and of the distribution of A. flavus across different food and feed categories and in Chinese traditional herbal medicines in China, for the period 2000-2020. We also highlight the health impacts of chronic dietary AF exposure, the recent advances in biological AF mitigation strategies in China, and recent Chinese AF standards.
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Affiliation(s)
- Firew Tafesse Mamo
- School of Food Science and Engineering, Food Safety Research Centre, Foshan University, Foshan 528231, China; (C.N.); (M.H.)
- Ethiopian Biotechnology Institute, Addis Ababa 5954, Ethiopia;
| | | | - Yougquan Zheng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China;
| | - Chengrong Nie
- School of Food Science and Engineering, Food Safety Research Centre, Foshan University, Foshan 528231, China; (C.N.); (M.H.)
| | - Mingjun He
- School of Food Science and Engineering, Food Safety Research Centre, Foshan University, Foshan 528231, China; (C.N.); (M.H.)
| | - Yang Liu
- School of Food Science and Engineering, Food Safety Research Centre, Foshan University, Foshan 528231, China; (C.N.); (M.H.)
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16
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Wang X, Subko K, Kildgaard S, Frisvad JC, Larsen TO. Mass Spectrometry-Based Network Analysis Reveals New Insights Into the Chemodiversity of 28 Species in Aspergillus section Flavi. FRONTIERS IN FUNGAL BIOLOGY 2021; 2:719420. [PMID: 37744124 PMCID: PMC10512371 DOI: 10.3389/ffunb.2021.719420] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 07/12/2021] [Indexed: 09/26/2023]
Abstract
Aspergillus section Flavi includes some of the most famous mycotoxin producing filamentous fungi known to mankind. In recent years a number of new species have been included in section Flavi, however these species have been much less studied from a chemical point of view. In this study, we explored one representative strain of a total of 28 fungal species in section Flavi by systematically evaluating the relationship between taxonomy and secondary metabolites with LC-MS/MS analysis for the first time and dereplication through an in-house database and the Global Natural Product Social Molecular Networking (GNPS) platform. This approach allowed rapid identification of two new cyclopiazonic acid producers (A. alliaceus and A. arachidicola) and two new tenuazonic acid producers (A. arachidicola and A. leporis). Moreover, for the first time we report species from section Flavi to produce fumifungin and sphingofungins B-D. Altogether, this study emphasizes that the chemical diversity of species in genus Aspergillus section Flavi is larger than previously recognized, and especially that understudied species are prolific producers of important mycotoxins such as fumi- and sphingofungins not previously reported from this section. Furthermore, our work demonstrates Global Natural Product Social (GNPS) Molecular Networking as a powerful tool for large-scale chemotaxonomic analysis of closely related species in filamentous fungi.
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Affiliation(s)
- Xinhui Wang
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Karolina Subko
- Food Machinery and Chemical (FMC) Agricultural Solutions, Hørsholm, Denmark
| | - Sara Kildgaard
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Jens C. Frisvad
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
| | - Thomas O. Larsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Lyngby, Denmark
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17
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Wang Z, Jiang Y, Xin X, An F. Bioactive indole alkaloids from insect derived endophytic Aspergillus lentulus. Fitoterapia 2021; 153:104973. [PMID: 34157376 DOI: 10.1016/j.fitote.2021.104973] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 05/11/2021] [Accepted: 05/21/2021] [Indexed: 12/17/2022]
Abstract
As part of our program to discover new bioactive agents from endophytic fungi, three new indole alkaloids (1-2, 4) along with twelve known compounds were isolated from an inset derived endophytic strain Aspergillus lentulus. Their structures were determined by comprehensive spectroscopic analyses of 1D/2D NMR and HR-ESI-MS data. The absolute configurations were confirmed by ECD calculation using Time-dependent Density functional theory (TD-DFT) at the B3LYP/6-31 + g (d, p) level and Rh2(OCOCF3)4-induced ECD experiments. Compounds 2, 4, 5, 13 and 15 exhibited moderate cytotoxic effects on A549 cell line with IC50 in the range of 17.92-48.29 μM. Compounds 1, 2 and 13-15 displayed the anti-bacterial activity against Xanthomonas oryzae pv. oryzae and Xanthomonas oryzae pv. oryzicola with MIC values ranging from 25 to 100 μg/mL.
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Affiliation(s)
- Zhijie Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China
| | - Yu Jiang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China
| | - Xiujuan Xin
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China
| | - Faliang An
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China.
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18
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Kifer D, Sulyok M, Jakšić D, Krska R, Šegvić Klarić M. Fungi and their metabolites in grain from individual households in Croatia. FOOD ADDITIVES & CONTAMINANTS. PART B, SURVEILLANCE 2021; 14:98-109. [PMID: 33583343 DOI: 10.1080/19393210.2021.1883746] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A total of 117 fungal metabolites were detected in grains collected in Gunja-G (flooded village) and Gornji Stupnik-GS (control village), located in the Zagreb County, Croatia. Major mycotoxins and derivatives (17), ergot alkaloids (14), Fusarium (23), Aspergillus (18), Penicillium (18), Alternaria (7) and other fungal and unspecific metabolites (20) were found. A higher number of metabolites co-occurred per sample in grains from G (115) than in GS (91). Regulated mycotoxins were below maximum limits except fumonisins B1,2 in 15-20% of grains and aflatoxin B1. Fusarium metabolites contaminated more than 50% of grains at both locations. Besides FB1,2, bikaverin, aurofusarin, culmorin and 15-hidroxyculmorin were detected at relatively high concentrations. Ergot alkaloids were detected at 2-18 times higher concentrations in grains from G as compared to GS. Majority of Aspergillus mycotoxins were present at a low frequency (5-15%). Penicillium metabolites recovered with higher frequency in GS (55-70%) than in G (20-55%). Alteranaria metabolites prevailed in grains from G (60-80%).
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Affiliation(s)
- Domagoj Kifer
- Department of Biophysics, University of Zagreb, Zagreb, Croatia
| | - Michael Sulyok
- Center for Analytical Chemistry, Department of Agrobiotechnology (Ifa-tulln), University of Natural Resources and Life Sciences, Vienna, Austria
| | - Daniela Jakšić
- Department of Microbiology, Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia
| | - Rudolf Krska
- Center for Analytical Chemistry, Department of Agrobiotechnology (Ifa-tulln), University of Natural Resources and Life Sciences, Vienna, Austria.,Institute for Global Food Security, School of Biological Sciences, Queens University Belfast, Belfast, UK
| | - Maja Šegvić Klarić
- Department of Microbiology, Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia
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19
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Adrover-Castellano ML, Schmidt JJ, Sherman DH. Biosynthetic Cyclization Catalysts for the Assembly of Peptide and Polyketide Natural Products. ChemCatChem 2021; 13:2095-2116. [PMID: 34335987 PMCID: PMC8320681 DOI: 10.1002/cctc.202001886] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Indexed: 12/13/2022]
Abstract
Many biologically active natural products are synthesized by nonribosomal peptide synthetases (NRPSs), polyketide synthases (PKSs) and their hybrids. These megasynthetases contain modules possessing distinct catalytic domains that allow for substrate initiation, chain extension, processing and termination. At the end of a module, a terminal domain, usually a thioesterase (TE), is responsible for catalyzing the release of the NRPS or PKS as a linear or cyclized product. In this review, we address the general cyclization mechanism of the TE domain, including oligomerization and the fungal C-C bond forming Claisen-like cyclases (CLCs). Additionally, we include examples of cyclization catalysts acting within or at the end of a module. Furthermore, condensation-like (CT) domains, terminal reductase (R) domains, reductase-like domains that catalyze Dieckmann condensation (RD), thioesterase-like Dieckmann cyclases, trans-acting TEs from the penicillin binding protein (PBP) enzyme family, product template (PT) domains and others will also be reviewed. The studies summarized here highlight the remarkable diversity of NRPS and PKS cyclization catalysts for the production of biologically relevant, complex cyclic natural products and related compounds.
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Affiliation(s)
| | - Jennifer J Schmidt
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216 (USA)
| | - David H Sherman
- Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109-2216 (USA)
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20
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Navale V, Vamkudoth KR, Ajmera S, Dhuri V. Aspergillus derived mycotoxins in food and the environment: Prevalence, detection, and toxicity. Toxicol Rep 2021; 8:1008-1030. [PMID: 34408970 PMCID: PMC8363598 DOI: 10.1016/j.toxrep.2021.04.013] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 04/20/2021] [Accepted: 04/27/2021] [Indexed: 12/16/2022] Open
Abstract
Aspergillus species are the paramount ubiquitous fungi that contaminate various food substrates and produce biochemicals known as mycotoxins. Aflatoxins (AFTs), ochratoxin A (OTA), patulin (PAT), citrinin (CIT), aflatrem (AT), secalonic acids (SA), cyclopiazonic acid (CPA), terrein (TR), sterigmatocystin (ST) and gliotoxin (GT), and other toxins produced by species of Aspergillus plays a major role in food and human health. Mycotoxins exhibited wide range of toxicity to the humans and animal models even at nanomolar (nM) concentration. Consumption of detrimental mycotoxins adulterated foodstuffs affects human and animal health even trace amounts. Bioaerosols consisting of spores and hyphal fragments are active elicitors of bronchial irritation and allergy, and challenging to the public health. Aspergillus is the furthermost predominant environmental contaminant unswervingly defile lives with a 40-90 % mortality risk in patients with conceded immunity. Genomics, proteomics, transcriptomics, and metabolomics approaches useful for mycotoxins' detection which are expensive. Antibody based detection of toxins chemotypes may result in cross-reactivity and uncertainty. Aptamers (APT) are single stranded DNA (ssDNA/RNA), are specifically binds to the target molecules can be generated by systematic evolution of ligands through exponential enrichment (SELEX). APT are fast, sensitive, simple, in-expensive, and field-deployable rapid point of care (POC) detection of toxins, and a better alternative to antibodies.
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Affiliation(s)
- Vishwambar Navale
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, New Delhi, India
| | - Koteswara Rao Vamkudoth
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, New Delhi, India
| | | | - Vaibhavi Dhuri
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, 411008, India
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21
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Co-Occurrence of Regulated and Emerging Mycotoxins in Corn Silage: Relationships with Fermentation Quality and Bacterial Communities. Toxins (Basel) 2021; 13:toxins13030232. [PMID: 33806727 PMCID: PMC8004697 DOI: 10.3390/toxins13030232] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/17/2021] [Accepted: 03/19/2021] [Indexed: 12/28/2022] Open
Abstract
Sixty-four corn silages were characterized for chemicals, bacterial community, and concentrations of several fungal metabolites. Silages were grouped in five clusters, based on detected mycotoxins, and they were characterized for being contaminated by (1) low levels of Aspergillus- and Penicillium-mycotoxins; (2) low levels of fumonisins and other Fusarium-mycotoxins; (3) high levels of Aspergillus-mycotoxins; (4) high levels of non-regulated Fusarium-mycotoxins; (5) high levels of fumonisins and their metabolites. Altersetin was detected in clusters 1, 3, and 5. Rugulusovin or brevianamide F were detected in several samples, with the highest concentration in cluster 3. Emodin was detected in more than 50.0% of samples of clusters 1, 3 and 5, respectively. Kojic acid occurred mainly in clusters 1 and 2 at very low concentrations. Regarding Fusarium mycotoxins, high occurrences were observed for FB3, FB4, FA1, whereas the average concentrations of FB6 and FA2 were lower than 12.4 µg/kg dry matter. Emerging Fusarium-produced mycotoxins, such as siccanol, moniliformin, equisetin, epiequisetin and bikaverin were detected in the majority of analyzed corn silages. Pestalotin, oxaline, phenopirrozin and questiomycin A were detected at high incidences. Concluding, this work highlighted that corn silages could be contaminated by a high number of regulated and emerging mycotoxins.
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22
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Corkidi G, Hernández-Herrera P, Montoya F, Gadêlha H, Darszon A. Long-term segmentation-free assessment of head-flagellum movement and intracellular calcium in swimming human sperm. J Cell Sci 2021; 134:jcs.250654. [PMID: 33431515 DOI: 10.1242/jcs.250654] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 12/14/2020] [Indexed: 12/31/2022] Open
Abstract
Human spermatozoa are the archetype of long-term self-organizing transport in nature and are critical for reproductive success. They utilize coordinated head and flagellar movements to swim long distances within the female reproductive tract in order to find and fertilize the egg. However, to date, long-term analysis of the sperm head-flagellar movements, or indeed those of other flagellated microorganisms, remains elusive due to limitations in microscopy and flagellar-tracking techniques. Here, we present a novel methodology based on local orientation and isotropy of bio-images to obtain long-term kinematic and physiological parameters of individual free-swimming spermatozoa without requiring image segmentation (thresholding). This computer-assisted segmentation-free method evaluates, for the first time, characteristics of the head movement and flagellar beating for up to 9.2 min. We demonstrate its powerful use by showing how releasing Ca2+ from internal stores significantly alters long-term sperm behavior. The method allows for straightforward generalization to other bio-imaging applications, such as studies of bull sperm and Trypanosoma, or indeed of other flagellated microorganisms - appealing to communities other than those investigating sperm biology.
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Affiliation(s)
- Gabriel Corkidi
- Laboratorio de Imágenes y Visión por Computadora, Departamento de Ingenería Celular y Biocatálisis, Instituto de Biotecnología, UNAM, 62210 Cuernavaca, México
| | - Paul Hernández-Herrera
- Laboratorio de Imágenes y Visión por Computadora, Departamento de Ingenería Celular y Biocatálisis, Instituto de Biotecnología, UNAM, 62210 Cuernavaca, México
| | - Fernando Montoya
- Laboratorio de Imágenes y Visión por Computadora, Departamento de Ingenería Celular y Biocatálisis, Instituto de Biotecnología, UNAM, 62210 Cuernavaca, México
| | - Hermes Gadêlha
- Department of Engineering Mathematics & Bristol Robotics Laboratory, University of Bristol, Bristol BS8 1QU, UK
| | - Alberto Darszon
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, UNAM, 62210 Cuernavaca, México
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23
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Bhattarai K, Bhattarai K, Kabir ME, Bastola R, Baral B. Fungal natural products galaxy: Biochemistry and molecular genetics toward blockbuster drugs discovery. ADVANCES IN GENETICS 2021; 107:193-284. [PMID: 33641747 DOI: 10.1016/bs.adgen.2020.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Secondary metabolites synthesized by fungi have become a precious source of inspiration for the design of novel drugs. Indeed, fungi are prolific producers of fascinating, diverse, structurally complex, and low-molecular-mass natural products with high therapeutic leads, such as novel antimicrobial compounds, anticancer compounds, immunosuppressive agents, among others. Given that these microorganisms possess the extraordinary capacity to secrete diverse chemical scaffolds, they have been highly exploited by the giant pharma companies to generate small molecules. This has been made possible because the isolation of metabolites from fungal natural sources is feasible and surpasses the organic synthesis of compounds, which otherwise remains a significant bottleneck in the drug discovery process. Here in this comprehensive review, we have discussed recent studies on different fungi (pathogenic, non-pathogenic, commensal, and endophytic/symbiotic) from different habitats (terrestrial and marines), the specialized metabolites they biosynthesize, and the drugs derived from these specialized metabolites. Moreover, we have unveiled the logic behind the biosynthesis of vital chemical scaffolds, such as NRPS, PKS, PKS-NRPS hybrid, RiPPS, terpenoids, indole alkaloids, and their genetic mechanisms. Besides, we have provided a glimpse of the concept behind mycotoxins, virulence factor, and host immune response based on fungal infections.
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Affiliation(s)
- Keshab Bhattarai
- Pharmaceutical Institute, Department of Pharmaceutical Biology, University of Tübingen, Tübingen, Germany
| | - Keshab Bhattarai
- Central Department of Chemistry, Tribhuvan University, Kirtipur, Kathmandu, Nepal
| | - Md Ehsanul Kabir
- Animal Health Research Division, Bangladesh Livestock Research Institute, Savar, Dhaka, Bangladesh
| | - Rina Bastola
- Spinal Cord Injury Association-Nepal (SCIAN), Pokhara, Nepal
| | - Bikash Baral
- Department of Biochemistry, University of Turku, Turku, Finland.
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24
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Scharf DH, Chankhamjon P, Scherlach K, Dworschak J, Heinekamp T, Roth M, Brakhage AA, Hertweck C. N-Heterocyclization in Gliotoxin Biosynthesis is Catalyzed by a Distinct Cytochrome P450 Monooxygenase. Chembiochem 2021; 22:336-339. [PMID: 32835438 PMCID: PMC7891397 DOI: 10.1002/cbic.202000550] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/24/2020] [Indexed: 01/03/2023]
Abstract
Gliotoxin and related epidithiodiketopiperazines (ETP) from diverse fungi feature highly functionalized hydroindole scaffolds with an array of medicinally and ecologically relevant activities. Mutation analysis, heterologous reconstitution, and biotransformation experiments revealed that a cytochrome P450 monooxygenase (GliF) from the human-pathogenic fungus Aspergillus fumigatus plays a key role in the formation of the complex heterocycle. In vitro assays using a biosynthetic precursor from a blocked mutant showed that GliF is specific to ETPs and catalyzes an unprecedented heterocyclization reaction that cannot be emulated with current synthetic methods. In silico analyses indicate that this rare biotransformation takes place in related ETP biosynthetic pathways.
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Affiliation(s)
- Daniel H. Scharf
- Department of Molecular and Applied MicrobiologyLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstrasse 11a07745JenaGermany
- Department of MicrobiologyZhejiang University School of MedicineYuhangtang Road 866Hangzhou310058P. R. China
- The Children's Hospital, Zhejiang University School of MedicineNational Clinical Research Center for Child HealthBinsheng Road 3333Hangzhou310052P. R. China
| | - Pranatchareeya Chankhamjon
- Department of Biomolecular ChemistryLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstrasse 11a07745JenaGermany
| | - Kirstin Scherlach
- Department of Biomolecular ChemistryLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstrasse 11a07745JenaGermany
| | - Jan Dworschak
- Department of Biomolecular ChemistryLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstrasse 11a07745JenaGermany
| | - Thorsten Heinekamp
- Department of Molecular and Applied MicrobiologyLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstrasse 11a07745JenaGermany
| | - Martin Roth
- Bio Pilot PlantLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstrasse 11a07745JenaGermany
| | - Axel A. Brakhage
- Department of Molecular and Applied MicrobiologyLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstrasse 11a07745JenaGermany
- Faculty of Biological SciencesFriedrich Schiller University Jena07743JenaGermany
| | - Christian Hertweck
- Department of Biomolecular ChemistryLeibniz Institute for Natural Product Research and Infection Biology (HKI)Beutenbergstrasse 11a07745JenaGermany
- Faculty of Biological SciencesFriedrich Schiller University Jena07743JenaGermany
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25
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Gao Z, Wang Y, Song H, Xu Z, Jia Y. Cascade Cyclization Reaction Initiated by Benzylic Carbocation of Indole: Scope and Mechanistic Insights. CHINESE J ORG CHEM 2021. [DOI: 10.6023/cjoc202102006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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26
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Gao Y, Du X, Li H, Wang Y. Genome sequence of Aspergillus flavus A7, a marine-derived fungus with antibacterial activity. Genome 2020; 64:719-733. [PMID: 33356862 DOI: 10.1139/gen-2020-0066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Due to the specific properties of the marine environment, marine microorganisms have exclusive physicochemical characteristics that are different from those of terrestrial microorganisms, which can produce various secondary metabolites (SMs) with considerable structural diversity and biological activity. In this study, three strains of coepiphytic Aspergillus with potential antibacterial activities, A7 (Aspergillus flavus), B27 (Aspergillus flavipes), and R12 (Aspergillus sydowii), were isolated from the South China Sea. Via the Illumina MiSeq sequencing platform, the genomes of the three strains were sequenced, and genome comparison showed the highest diversity of the biosynthetic gene clusters (BGCs) in A7. In addition, a comparison of physiological and genomic characteristics between A7 and other A. flavus strains demonstrated the superior environmental adaptability of A7, which is apparently consistent with the genetic richness of BGCs. By assigning reads to known BGCs, putative BGCs were allocated in A7 that corresponded to various SMs, including naphthopyrone, pyranonigrin E, and cyclopiazonic acids. Based on gene homology analysis, we surmise that a region is involved in the biosynthesis of ustiloxin-like RiPPs, a less thoroughly studied SM in fungi. Our results provide genetic information for the investigation of marine Aspergillus spp., which may help to elucidate their chemical diversity and adaptive strategies.
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Affiliation(s)
- Yaru Gao
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 211198, PR China.,School of Life Science and Technology, China Pharmaceutical University, Nanjing 211198, PR China
| | - Xinyang Du
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 211198, PR China.,School of Life Science and Technology, China Pharmaceutical University, Nanjing 211198, PR China
| | - Huanhuan Li
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 211198, PR China.,School of Life Science and Technology, China Pharmaceutical University, Nanjing 211198, PR China
| | - Ying Wang
- School of Life Science and Technology, China Pharmaceutical University, Nanjing 211198, PR China.,School of Life Science and Technology, China Pharmaceutical University, Nanjing 211198, PR China
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27
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Fountain J, Pandey A, Nayak S, Bajaj P, Wang H, Kumar V, Chitikineni A, Abbas H, Scully B, Kemerait R, Pandey M, Guo B, Varshney R. Transcriptional responses of toxigenic and atoxigenic isolates of Aspergillus flavus to oxidative stress in aflatoxin-conducive and non-conducive media. WORLD MYCOTOXIN J 2020. [DOI: 10.3920/wmj2020.2566] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Aflatoxin production by isolates of Aspergillus flavus varies, ranging from highly toxigenic to completely atoxigenic. Several mechanisms have been identified which regulate aflatoxin production including medium carbon source and oxidative stress. In recent studies, aflatoxin production has been implicated in partially ameliorating oxidative stress in A. flavus. To better understand the role of aflatoxin production in oxidative stress responses, a selection of toxigenic and atoxigenic isolates of A. flavus with moderate to high oxidative stress tolerance were exposed to increasing concentrations of H2O2 in both aflatoxin-conducive and non-conducive media. Mycelial mats were collected for global transcriptome sequencing followed by differential expression, functional prediction, and weighted co-expression analyses. Oxidative stress and medium carbon source had a significant effect on the expression of several secondary metabolite gene clusters including those for aflatoxin, aflatrem, aflavarin, cyclopiazonic acid, and kojic acid. Atoxigenic biological control isolates showed less differential expression under stress than other atoxigenic isolates suggesting expression profiles may be useful in screening. Increasing stress also resulted in regulation of SakA/Hog1 and MpkA MAP kinase signalling pathways pointing to their potential roles in regulating oxidative stress responses. Their expression was also influenced by medium carbon source. These results suggest that aflatoxin production along with that of other mycotoxins may occur as part of a concerted coping mechanism for oxidative stress and its effects in the environment. This mechanism is also regulated by availability of simple sugars and glycolytic compounds for their biosynthesis.
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Affiliation(s)
- J.C. Fountain
- USDA-ARS, Crop Protection and Management Research Unit, Tifton, GA 31793, USA
- Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Starkville, MS 39762, USA
| | - A.K. Pandey
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
| | - S.N. Nayak
- Department of Biotechnology, University of Agricultural Sciences, Dharwad, Karnataka 580005, India
| | - P. Bajaj
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
| | - H. Wang
- Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA
| | - V. Kumar
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
| | - A. Chitikineni
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
| | - H.K. Abbas
- USDA-ARS, Biological Control of Pests Research Unit, Stoneville, MS, USA
| | - B.T. Scully
- USDA-ARS, National Horticultural Research Laboratory, Fort Pierce, FL, USA
| | - R.C. Kemerait
- Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA
| | - M.K. Pandey
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
| | - B. Guo
- USDA-ARS, Crop Protection and Management Research Unit, Tifton, GA 31793, USA
| | - R.K. Varshney
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
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28
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Fountain J, Pandey A, Nayak S, Bajaj P, Wang H, Kumar V, Chitikineni A, Abbas H, Scully B, Kemerait R, Pandey M, Guo B, Varshney R. Transcriptional responses of toxigenic and atoxigenic isolates of Aspergillus flavus to oxidative stress in aflatoxin-conducive and non-conducive media. WORLD MYCOTOXIN J 2020. [DOI: 10.3920/wmj2020.test2566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Aflatoxin production by isolates of Aspergillus flavus varies, ranging from highly toxigenic to completely atoxigenic. Several mechanisms have been identified which regulate aflatoxin production including medium carbon source and oxidative stress. In recent studies, aflatoxin production has been implicated in partially ameliorating oxidative stress in A. flavus. To better understand the role of aflatoxin production in oxidative stress responses, a selection of toxigenic and atoxigenic isolates of A. flavus with moderate to high oxidative stress tolerance were exposed to increasing concentrations of H2O2 in both aflatoxin-conducive and non-conducive media. Mycelial mats were collected for global transcriptome sequencing followed by differential expression, functional prediction, and weighted co-expression analyses. Oxidative stress and medium carbon source had a significant effect on the expression of several secondary metabolite gene clusters including those for aflatoxin, aflatrem, aflavarin, cyclopiazonic acid, and kojic acid. Atoxigenic biological control isolates showed less differential expression under stress than other atoxigenic isolates suggesting expression profiles may be useful in screening. Increasing stress also resulted in regulation of SakA/Hog1 and MpkA MAP kinase signalling pathways pointing to their potential roles in regulating oxidative stress responses. Their expression was also influenced by medium carbon source. These results suggest that aflatoxin production along with that of other mycotoxins may occur as part of a concerted coping mechanism for oxidative stress and its effects in the environment. This mechanism is also regulated by availability of simple sugars and glycolytic compounds for their biosynthesis.
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Affiliation(s)
- J.C. Fountain
- USDA-ARS, Crop Protection and Management Research Unit, Tifton, GA 31793, USA
- Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Starkville, MS 39762, USA
| | - A.K. Pandey
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
| | - S.N. Nayak
- Department of Biotechnology, University of Agricultural Sciences, Dharwad, Karnataka 580005, India
| | - P. Bajaj
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
| | - H. Wang
- Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA
| | - V. Kumar
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
| | - A. Chitikineni
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
| | - H.K. Abbas
- USDA-ARS, Biological Control of Pests Research Unit, Stoneville, MS, USA
| | - B.T. Scully
- USDA-ARS, National Horticultural Research Laboratory, Fort Pierce, FL, USA
| | - R.C. Kemerait
- Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA
| | - M.K. Pandey
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
| | - B. Guo
- USDA-ARS, Crop Protection and Management Research Unit, Tifton, GA 31793, USA
| | - R.K. Varshney
- Center of Excellence in Genomics & Systems Biology, International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, Telangana 502324, India
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29
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Uka V, Cary JW, Lebar MD, Puel O, De Saeger S, Diana Di Mavungu J. Chemical repertoire and biosynthetic machinery of the Aspergillus flavus secondary metabolome: A review. Compr Rev Food Sci Food Saf 2020; 19:2797-2842. [PMID: 33337039 DOI: 10.1111/1541-4337.12638] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 08/23/2020] [Accepted: 08/24/2020] [Indexed: 12/18/2022]
Abstract
Filamentous fungi represent a rich source of extrolites, including secondary metabolites (SMs) comprising a great variety of astonishing structures and interesting bioactivities. State-of-the-art techniques in genome mining, genetic manipulation, and secondary metabolomics have enabled the scientific community to better elucidate and more deeply appreciate the genetic and biosynthetic chemical arsenal of these microorganisms. Aspergillus flavus is best known as a contaminant of food and feed commodities and a producer of the carcinogenic family of SMs, aflatoxins. This fungus produces many SMs including polyketides, ribosomal and nonribosomal peptides, terpenoids, and other hybrid molecules. This review will discuss the chemical diversity, biosynthetic pathways, and biological/ecological role of A. flavus SMs, as well as their significance concerning food safety and security.
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Affiliation(s)
- Valdet Uka
- Center of Excellence in Mycotoxicology and Public Health, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.,Division of Pharmacy, Faculty of Medicine, University of Pristina, Pristina, Kosovo
| | - Jeffrey W Cary
- Southern Regional Research Center, USDA-ARS, New Orleans, Louisiana
| | - Matthew D Lebar
- Southern Regional Research Center, USDA-ARS, New Orleans, Louisiana
| | - Olivier Puel
- Toxalim (Research Centre in Food Toxicology), INRAE, ENVT, INP-Purpan, UPS, Université de Toulouse, Toulouse, France
| | - Sarah De Saeger
- Center of Excellence in Mycotoxicology and Public Health, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - José Diana Di Mavungu
- Center of Excellence in Mycotoxicology and Public Health, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
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30
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Minami A, Ugai T, Ozaki T, Oikawa H. Predicting the chemical space of fungal polyketides by phylogeny-based bioinformatics analysis of polyketide synthase-nonribosomal peptide synthetase and its modification enzymes. Sci Rep 2020; 10:13556. [PMID: 32782278 PMCID: PMC7421883 DOI: 10.1038/s41598-020-70177-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 07/24/2020] [Indexed: 11/10/2022] Open
Abstract
Fungal polyketide synthase (PKS)–nonribosomal peptide synthetase (NRPS) hybrids are key enzymes for synthesizing structurally diverse hybrid natural products (NPs) with characteristic biological activities. Predicting their chemical space is of particular importance in the field of natural product chemistry. However, the unexplored programming rule of the PKS module has prevented prediction of its chemical structure based on amino acid sequences. Here, we conducted a phylogenetic analysis of 884 PKS–NRPS hybrids and a modification enzyme analysis of the corresponding biosynthetic gene cluster, revealing a hidden relationship between its genealogy and core structures. This unexpected result allowed us to predict 18 biosynthetic gene cluster (BGC) groups producing known carbon skeletons (number of BGCs; 489) and 11 uncharacterized BGC groups (171). The limited number of carbon skeletons suggests that fungi tend to select PK skeletons for survival during their evolution. The possible involvement of a horizontal gene transfer event leading to the diverse distribution of PKS–NRPS genes among fungal species is also proposed. This study provides insight into the chemical space of fungal PKs and the distribution of their biosynthetic gene clusters.
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Affiliation(s)
- Atsushi Minami
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan.
| | - Takahiro Ugai
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan
| | - Taro Ozaki
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan
| | - Hideaki Oikawa
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, 060-0810, Japan.
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31
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Kjærbølling I, Vesth T, Frisvad JC, Nybo JL, Theobald S, Kildgaard S, Petersen TI, Kuo A, Sato A, Lyhne EK, Kogle ME, Wiebenga A, Kun RS, Lubbers RJM, Mäkelä MR, Barry K, Chovatia M, Clum A, Daum C, Haridas S, He G, LaButti K, Lipzen A, Mondo S, Pangilinan J, Riley R, Salamov A, Simmons BA, Magnuson JK, Henrissat B, Mortensen UH, Larsen TO, de Vries RP, Grigoriev IV, Machida M, Baker SE, Andersen MR. A comparative genomics study of 23 Aspergillus species from section Flavi. Nat Commun 2020; 11:1106. [PMID: 32107379 PMCID: PMC7046712 DOI: 10.1038/s41467-019-14051-y] [Citation(s) in RCA: 92] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 12/02/2019] [Indexed: 02/01/2023] Open
Abstract
Section Flavi encompasses both harmful and beneficial Aspergillus species, such as Aspergillus oryzae, used in food fermentation and enzyme production, and Aspergillus flavus, food spoiler and mycotoxin producer. Here, we sequence 19 genomes spanning section Flavi and compare 31 fungal genomes including 23 Flavi species. We reassess their phylogenetic relationships and show that the closest relative of A. oryzae is not A. flavus, but A. minisclerotigenes or A. aflatoxiformans and identify high genome diversity, especially in sub-telomeric regions. We predict abundant CAZymes (598 per species) and prolific secondary metabolite gene clusters (73 per species) in section Flavi. However, the observed phenotypes (growth characteristics, polysaccharide degradation) do not necessarily correlate with inferences made from the predicted CAZyme content. Our work, including genomic analyses, phenotypic assays, and identification of secondary metabolites, highlights the genetic and metabolic diversity within section Flavi.
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Affiliation(s)
- Inge Kjærbølling
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Tammi Vesth
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Jens C Frisvad
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Jane L Nybo
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Sebastian Theobald
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Sara Kildgaard
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Thomas Isbrandt Petersen
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Alan Kuo
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Atsushi Sato
- Kikkoman Corporation, 250 Noda, 278-0037, Noda, Japan
| | - Ellen K Lyhne
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Martin E Kogle
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Ad Wiebenga
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Roland S Kun
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Ronnie J M Lubbers
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Miia R Mäkelä
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Viikinkaari 9, Helsinki, Finland
| | - Kerrie Barry
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Mansi Chovatia
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Alicia Clum
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Chris Daum
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Sajeet Haridas
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Guifen He
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Kurt LaButti
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Stephen Mondo
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Jasmyn Pangilinan
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Robert Riley
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Asaf Salamov
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
| | - Blake A Simmons
- US Department of Energy Joint BioEnergy Institute, 5885 Hollis St., Emeryville, CA, 94608, USA
| | - Jon K Magnuson
- US Department of Energy Joint BioEnergy Institute, 5885 Hollis St., Emeryville, CA, 94608, USA
| | - Bernard Henrissat
- Architecture et Fonction des Macromolécules Biologiques, (CNRS UMR 7257, Aix-Marseille University, 163 Avenue de Luminy, Parc Scientifique et Technologique de Luminy, 13288, Marseille, France
| | - Uffe H Mortensen
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Thomas O Larsen
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Igor V Grigoriev
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
- Department of Plant and Microbial Biology, University of California, 111 Koshland Hall, Berkeley, CA, 94720, USA
| | - Masayuki Machida
- Kanazawa Institute of Technology, 3 Chome-1, 924-0838 Yatsukaho, Hakusan-shi, Ishikawa-ken, Japan
| | - Scott E Baker
- US Department of Energy Joint BioEnergy Institute, 5885 Hollis St., Emeryville, CA, 94608, USA
- Environmental Molecular Sciences Division, Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, 902 Battelle Blvd, Richland, WA, 99354, USA
| | - Mikael R Andersen
- Department of Biotechnology and Bioengineering, Technical University of Denmark, Søltoft Plads 223, 2800, Kongens Lyngby, Denmark.
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Pfliegler WP, Pócsi I, Győri Z, Pusztahelyi T. The Aspergilli and Their Mycotoxins: Metabolic Interactions With Plants and the Soil Biota. Front Microbiol 2020; 10:2921. [PMID: 32117074 PMCID: PMC7029702 DOI: 10.3389/fmicb.2019.02921] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 12/04/2019] [Indexed: 01/06/2023] Open
Abstract
Species of the highly diverse fungal genus Aspergillus are well-known agricultural pests, and, most importantly, producers of various mycotoxins threatening food safety worldwide. Mycotoxins are studied predominantly from the perspectives of human and livestock health. Meanwhile, their roles are far less known in nature. However, to understand the factors behind mycotoxin production, the roles of the toxins of Aspergilli must be understood from a complex ecological perspective, taking mold-plant, mold-microbe, and mold-animal interactions into account. The Aspergilli may switch between saprophytic and pathogenic lifestyles, and the production of secondary metabolites, such as mycotoxins, may vary according to these fungal ways of life. Recent studies highlighted the complex ecological network of soil microbiotas determining the niches that Aspergilli can fill in. Interactions with the soil microbiota and soil macro-organisms determine the role of secondary metabolite production to a great extent. While, upon infection of plants, metabolic communication including fungal secondary metabolites like aflatoxins, gliotoxin, patulin, cyclopiazonic acid, and ochratoxin, influences the fate of both the invader and the host. In this review, the role of mycotoxin producing Aspergillus species and their interactions in the ecosystem are discussed. We intend to highlight the complexity of the roles of the main toxic secondary metabolites as well as their fate in natural environments and agriculture, a field that still has important knowledge gaps.
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Affiliation(s)
- Walter P. Pfliegler
- Department of Molecular Biotechnology and Microbiology, Institute of Biotechnology, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary
| | - István Pócsi
- Department of Molecular Biotechnology and Microbiology, Institute of Biotechnology, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary
| | - Zoltán Győri
- Institute of Nutrition, Faculty of Agricultural and Food Sciences and Environmental Management, University of Debrecen, Debrecen, Hungary
| | - Tünde Pusztahelyi
- Central Laboratory of Agricultural and Food Products, Faculty of Agricultural and Food Sciences and Environmental Management, University of Debrecen, Debrecen, Hungary
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Panduwawala TD, Iqbal S, Thompson AL, Genov M, Pretsch A, Pretsch D, Liu S, Ebright RH, Howells A, Maxwell A, Moloney MG. Functionalised bicyclic tetramates derived from cysteine as antibacterial agents. Org Biomol Chem 2019; 17:5615-5632. [PMID: 31120090 PMCID: PMC6686852 DOI: 10.1039/c9ob01076a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Routes to bicyclic tetramates derived from cysteine permitting ready incorporation of functionality at two different points around the periphery of a heterocyclic skeleton are reported. This has enabled the identification of systems active against Gram-positive bacteria, some of which show gyrase and RNA polymerase inhibitory activity. In particular, tetramates substituted with glycosyl side chains, chosen to impart polarity and aqueous solubility, show high antibacterial activity coupled with modest gyrase/polymerase activity in two cases. An analysis of physicochemical properties indicates that the antibacterially active tetramates generally occupy physicochemical space with MW of 300-600, clog D7.4 of -2.5 to 4 and rel. PSA of 11-22%. This work demonstrates that biologically active 3D libraries are readily available by manipulation of a tetramate skeleton.
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Affiliation(s)
- Tharindi D Panduwawala
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, UK.
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Liu H, Chen L, Yuan K, Jia Y. A Ten‐Step Total Synthesis of Speradine C. Angew Chem Int Ed Engl 2019; 58:6362-6365. [DOI: 10.1002/anie.201902004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 03/10/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Haichao Liu
- State Key Laboratory of Natural and Biomimetic DrugsSchool of Pharmaceutical SciencesPeking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Lijun Chen
- State Key Laboratory of Natural and Biomimetic DrugsSchool of Pharmaceutical SciencesPeking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Kuo Yuan
- State Key Laboratory of Natural and Biomimetic DrugsSchool of Pharmaceutical SciencesPeking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Yanxing Jia
- State Key Laboratory of Natural and Biomimetic DrugsSchool of Pharmaceutical SciencesPeking University Xue Yuan Rd. 38 Beijing 100191 China
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Peromingo B, Rodríguez A, Delgado J, Córdoba JJ, Rodríguez M. Relationship between cyclopiazonic acid production and gene expression in Penicillium griseofulvum under dry-cured ham processing environmental conditions. Mycotoxin Res 2019; 35:353-361. [PMID: 30972701 DOI: 10.1007/s12550-019-00357-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 03/15/2019] [Accepted: 03/19/2019] [Indexed: 12/29/2022]
Abstract
Cyclopiazonic acid (CPA)-producing Penicillium griseofulvum is usually found on the dry-cured ham surface during its ripening. The objective of this work was to evaluate the effect of temperature and water activity (aw) of dry-cured ham processing on growth, CPA production, and temporal relative expression of genes involved in CPA biosynthesis on dry-cured meat-based media. P. griseofulvum CECT 2919 grew faster than P. griseofulvum IBT 14319 in all conditions tested, although no growth occurred at 0.85 aw. Besides, the dry-cured ham-based medium favoured CPA synthesis for both strains compared to the meat-based medium. For the strain CECT 2919, the expression of the mfs-1 and pks-nrps genes were stimulated at 0.90 and 0.95 aw, respectively, while the dmaT gene expression was inhibited during the incubation time. By contrast, the strain IBT 14319 showed that the dmaT gene expression was stimulated at 0.90 aw, while the pks-nrps and mfs-1 genes were repressed throughout incubation time. In conclusion, it is necessary to reduce aw on the surface of the hams below 0.85 during ripening before to increase temperature to reduce growth of P. griseofulvum and CPA production. This information may be useful to design preventive and corrective actions to minimise risks associated with the presence of CPA in dry-cured ham.
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Affiliation(s)
- Belén Peromingo
- Food Hygiene and Safety, Meat and Meat Products Research Institute. Faculty of Veterinary Science, University of Extremadura, Avda. de las Ciencias, s/n, 10003, Cáceres, Spain
| | - Alicia Rodríguez
- Food Hygiene and Safety, Meat and Meat Products Research Institute. Faculty of Veterinary Science, University of Extremadura, Avda. de las Ciencias, s/n, 10003, Cáceres, Spain
| | - Josué Delgado
- Heart Clinical Unit, Virgen de la Victoria University Clinic Hospital, Institute of Biomedical Research in Malaga, IBIMA, CIBERCV, University of Málaga, Málaga, Spain
| | - Juan J Córdoba
- Food Hygiene and Safety, Meat and Meat Products Research Institute. Faculty of Veterinary Science, University of Extremadura, Avda. de las Ciencias, s/n, 10003, Cáceres, Spain
| | - Mar Rodríguez
- Food Hygiene and Safety, Meat and Meat Products Research Institute. Faculty of Veterinary Science, University of Extremadura, Avda. de las Ciencias, s/n, 10003, Cáceres, Spain.
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Affiliation(s)
- Haichao Liu
- State Key Laboratory of Natural and Biomimetic DrugsSchool of Pharmaceutical SciencesPeking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Lijun Chen
- State Key Laboratory of Natural and Biomimetic DrugsSchool of Pharmaceutical SciencesPeking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Kuo Yuan
- State Key Laboratory of Natural and Biomimetic DrugsSchool of Pharmaceutical SciencesPeking University Xue Yuan Rd. 38 Beijing 100191 China
| | - Yanxing Jia
- State Key Laboratory of Natural and Biomimetic DrugsSchool of Pharmaceutical SciencesPeking University Xue Yuan Rd. 38 Beijing 100191 China
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Delgado J, Peromingo B, Rodríguez A, Rodríguez M. Biocontrol of Penicillium griseofulvum to reduce cyclopiazonic acid contamination in dry-fermented sausages. Int J Food Microbiol 2018; 293:1-6. [PMID: 30616199 DOI: 10.1016/j.ijfoodmicro.2018.12.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 12/19/2018] [Accepted: 12/24/2018] [Indexed: 11/17/2022]
Abstract
Dry-fermented sausages are very appreciated by consumers. The environmental conditions during its ripening favor colonization of their surface by toxigenic molds. These molds contribute to the development of sensory characteristics; however, some of them could produce mycotoxins such as cyclopiazonic acid (CPA). CPA is mainly produced by Penicillium commune and Penicillium griseofulvum which have been found in dry-cured meat products. Thus, strategies to prevent the CPA contamination in dry-fermented sausages are needed. The objective of this work was to evaluate the ability of P. griseofulvum to produce CPA in dry-fermented sausage during its ripening as well as to test different strategies to prevent CPA production. The ability of PgAFP antifungal protein-producing Penicillium chrysogenum, Debaryomyces hansenii and Pediococcus acidilactici for inhibiting CPA production by P. griseofulvum was tested on dry-fermented sausage-based medium. Only P. chrysogenum inhibited the CPA production, so this mold was co-inoculated with P. griseofulvum on sausages whose ripening was performed at low temperature. CPA reached around 800 ng/g in the control batch, being reduced to 20 ng/g by the presence of P. chrysogenum. This work demonstrates the risk posed by CPA on dry-fermented sausages, and provides a successful strategy to prevent this hazard.
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Affiliation(s)
- Josué Delgado
- Food Hygiene and Safety, Meat and Meat Products Research Institute, Faculty of Veterinary Science, University of Extremadura, Avda, de las Ciencias, s/n, 10003 Cáceres, Spain
| | - Belén Peromingo
- Food Hygiene and Safety, Meat and Meat Products Research Institute, Faculty of Veterinary Science, University of Extremadura, Avda, de las Ciencias, s/n, 10003 Cáceres, Spain
| | - Alicia Rodríguez
- Food Hygiene and Safety, Meat and Meat Products Research Institute, Faculty of Veterinary Science, University of Extremadura, Avda, de las Ciencias, s/n, 10003 Cáceres, Spain
| | - Mar Rodríguez
- Food Hygiene and Safety, Meat and Meat Products Research Institute, Faculty of Veterinary Science, University of Extremadura, Avda, de las Ciencias, s/n, 10003 Cáceres, Spain.
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Bonyadi F, Hasanzadeh S, Malekinejad H, Najafi G. Cyclopiazonic acid decreases sperm quality and in vitro fertilisation rate in mice. WORLD MYCOTOXIN J 2018. [DOI: 10.3920/wmj2018.2337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The presence of cyclopiazonic acid (CPA) as a mycotoxin has been reported in feed and foodstuffs. The aim of this investigation was to determine the effects of CPA on reproductive functions of male mice. In this experiment, 40 mature male mice were randomly assigned into five groups (n=8): control, control-sham, CPA (0.03 mg/kg, body weight (BW)), CPA (0.06 mg/kg, BW) and CPA (0.12 mg/kg, BW). Following 28 days exposure to CPA, sperm quality parameters, in vitro fertilisation (IVF) capacity of sperms, serum testosterone level, Leydig cells number and serum total antioxidant capacity (TAC) were analysed. The results revealed a significant (P<0.05) reduction in sperm count, sperm viability, sperm motility, chromatin quality of sperm, sperms with intact DNA, IVF rate, testosterone level, Leydig cell distribution and TAC in comparison to the control group. The most prominent detrimental effects of CPA were found at the highest given dose level. Our results suggest that CPA at higher dose levels exerts detrimental effects on the male reproductive system. Moreover, these descriptive warrant further investigations into the specific mechanisms of action and the effects of CPA on spermatogenesis.
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Affiliation(s)
- F. Bonyadi
- Department of Basic Science, Histology section, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
| | - S. Hasanzadeh
- Department of Basic Science, Histology section, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
| | - H. Malekinejad
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Urmia University of Medical Sciences, Urmia, Iran
| | - G. Najafi
- Department of Basic Science, Anatomy and Embryology section, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran
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Caceres I, Snini SP, Puel O, Mathieu F. Streptomyces roseolus, A Promising Biocontrol Agent Against Aspergillus flavus, the Main Aflatoxin B₁ Producer. Toxins (Basel) 2018; 10:toxins10110442. [PMID: 30380704 PMCID: PMC6267218 DOI: 10.3390/toxins10110442] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 10/26/2018] [Accepted: 10/27/2018] [Indexed: 12/20/2022] Open
Abstract
Crop contamination by aflatoxin B1 is a current problem in tropical and subtropical regions. In the future, this contamination risk may be expanded to European countries due to climate change. The development of alternative strategies to prevent mycotoxin contamination that further contribute to the substitution of phytopharmaceutical products are thus needed. For this, a promising method resides in the use of biocontrol agents. Several actinobacteria strains have demonstrated to effectively reduce the aflatoxin B1 concentration. Nevertheless, the molecular mechanism of action by which these biological agents reduce the mycotoxin concentration has not been determined. The aim of the present study was to test the potential use of Streptomyces roseolus as a biocontrol agent against aflatoxin B1 contamination. Co-cultures with Aspergillus flavus were conducted, and the molecular fungal response was investigated through analyzing the q-PCR expression of 65 genes encoding relevant fungal functions. Moreover, kojic and cyclopiazonic acid concentrations, as well as morphological fungal changes were also analyzed. The results demonstrated that reduced concentrations of aflatoxin B1 and kojic acid were respectively correlated with the down-regulation of the aflatoxin B1 gene cluster and kojR gene expression. Moreover, a fungal hypersporulated phenotype and a general over-expression of genes involved in fungal development were observed in the co-culture condition.
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Affiliation(s)
- Isaura Caceres
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, 31326 Toulouse, France.
| | - Selma P Snini
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, 31326 Toulouse, France.
| | - Olivier Puel
- Toxalim (Research Center in Food Toxicology), Université de Toulouse, INRA, ENVT, INP-Purpan, 31300 Toulouse, France.
| | - Florence Mathieu
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, 31326 Toulouse, France.
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Mullowney MW, McClure RA, Robey MT, Kelleher NL, Thomson RJ. Natural products from thioester reductase containing biosynthetic pathways. Nat Prod Rep 2018; 35:847-878. [PMID: 29916519 PMCID: PMC6146020 DOI: 10.1039/c8np00013a] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Covering: up to 2018 Thioester reductase domains catalyze two- and four-electron reductions to release natural products following assembly on nonribosomal peptide synthetases, polyketide synthases, and their hybrid biosynthetic complexes. This reductive off-loading of a natural product yields an aldehyde or alcohol, can initiate the formation of a macrocyclic imine, and contributes to important intermediates in a variety of biosyntheses, including those for polyketide alkaloids and pyrrolobenzodiazepines. Compounds that arise from reductase-terminated biosynthetic gene clusters are often reactive and exhibit biological activity. Biomedically important examples include the cancer therapeutic Yondelis (ecteinascidin 743), peptide aldehydes that inspired the first therapeutic proteasome inhibitor bortezomib, and numerous synthetic derivatives and antibody drug conjugates of the pyrrolobenzodiazepines. Recent advances in microbial genomics, metabolomics, bioinformatics, and reactivity-based labeling have facilitated the detection of these compounds for targeted isolation. Herein, we summarize known natural products arising from this important category, highlighting their occurrence in Nature, biosyntheses, biological activities, and the technologies used for their detection and identification. Additionally, we review publicly available genomic data to highlight the remaining potential for novel reductively tailored compounds and drug leads from microorganisms. This thorough retrospective highlights various molecular families with especially privileged bioactivity while illuminating challenges and prospects toward accelerating the discovery of new, high value natural products.
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Affiliation(s)
- Michael W Mullowney
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA.
| | - Ryan A McClure
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA.
| | - Matthew T Robey
- Department of Molecular Biosciences, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
| | - Neil L Kelleher
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA. and Department of Molecular Biosciences, Northwestern University, 2205 Tech Drive, Evanston, IL 60208, USA
| | - Regan J Thomson
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA.
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Cao T, Ling J, Liu Y, Chen X, Tian X, Meng D, Pan H, Hu J, Wang N. Characterization and abolishment of the cyclopiazonic acids produced by Aspergillus oryzae HMP-F28. Biosci Biotechnol Biochem 2018; 82:1832-1839. [PMID: 29985105 DOI: 10.1080/09168451.2018.1490170] [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] [Indexed: 12/18/2022]
Abstract
Extracellular alkalinization and H2O2 production are important early events during induced resistance establishment in plants. In a screen for metabolites as plant resistance activators from 98 fungal isolates associated with marine sponge Hymeniacidon perleve, the cyclopiazonic acids (CPAs) produced by Aspergillus oryzae HMP-F28 induced significant extracellular alkalinization coupled with augmented H2O2 production in tobacco cell suspensions. Bioassay-guided fractionation led to the isolation and structural elucidation of a new CPA congener (4, 3-hydroxysperadine A) and three known ones (1-3). To construct a mutasynthetic strain to generate unnatural CPA analogues, a hybrid pks-nrps gene (cpaS) was disrupted to abolish the production of the critical precursor of cyclo-acetoacetyl-L-tryptophan (cAATrp) and all the downstream CPA products. Elimination of cAATrp will allow cAATrp mimics being processed by the CPA biosynthetic machinery to produce CPA derivatives with designed structural features.
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Affiliation(s)
- Ting Cao
- a Institute of Applied Ecology , Chinese Academy of Sciences , Shenyang , China.,b College of Life Sciences , University of Chinese Academy of Sciences , Beijing , China
| | - Junhong Ling
- c School of Traditional Chinese Materia Medica , Shenyang Pharmaceutical University , Shenyang , China
| | - Yi Liu
- a Institute of Applied Ecology , Chinese Academy of Sciences , Shenyang , China.,c School of Traditional Chinese Materia Medica , Shenyang Pharmaceutical University , Shenyang , China
| | - Xiaoqi Chen
- a Institute of Applied Ecology , Chinese Academy of Sciences , Shenyang , China.,b College of Life Sciences , University of Chinese Academy of Sciences , Beijing , China
| | - Xiaoyue Tian
- a Institute of Applied Ecology , Chinese Academy of Sciences , Shenyang , China.,c School of Traditional Chinese Materia Medica , Shenyang Pharmaceutical University , Shenyang , China
| | - Dali Meng
- c School of Traditional Chinese Materia Medica , Shenyang Pharmaceutical University , Shenyang , China
| | - Huaqi Pan
- a Institute of Applied Ecology , Chinese Academy of Sciences , Shenyang , China
| | - Jiangchun Hu
- a Institute of Applied Ecology , Chinese Academy of Sciences , Shenyang , China
| | - Nan Wang
- a Institute of Applied Ecology , Chinese Academy of Sciences , Shenyang , China
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Yin G, Hua SST, Pennerman KK, Yu J, Bu L, Sayre RT, Bennett JW. Genome sequence and comparative analyses of atoxigenic Aspergillus flavus WRRL 1519. Mycologia 2018; 110:482-493. [PMID: 29969379 DOI: 10.1080/00275514.2018.1468201] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Aflatoxins are toxic secondary metabolites produced by Aspergillus flavus and a few other closely related species of Aspergillus. These highly toxigenic and carcinogenic mycotoxins contaminate global food and feed supplies, posing widespread health risks to humans and domestic animals. Field application of nonaflatoxigenic strains of A. flavus to compete against aflatoxigenic strains has emerged as one of the best management practices for reducing aflatoxins contamination, yielding successful commercial products for corn, cotton seed, and peanuts. In this study, we sequenced the genome and transcriptome of atoxigenic (does not produce aflatoxin or cyclopiazonic acid) A. flavus strain WRRL 1519 isolated from a tree nut orchard to define the genetic characteristics of the strain in relation to aflatoxigenic and other nonaflatoxigenic A. flavus strains. WRRL 1519 strain was similar to other strains in size (38.0 Mb), GC content (47.2%), number of predicted secondary metabolite gene clusters (46), and number of putative proteins (12 121). About 87.4% of the predicted proteome had high shared identity with protein sequences derived from other A. flavus genomes. However, the atoxigenic A. flavus strain WRRL 1519 had deletions, or low shared identity, for many genes in the clusters required for aflatoxins and cyclopiazonic acid (CPA) synthesis. Over half of the aflatoxin synthesis gene cluster was missing, and none of the components of the CPA gene cluster were identified with high sequence similarity. Importantly, the strain appeared to maintain functional sequences of several genes thought to be required for high infectivity. Since the ability to grow on target crop is an important attribute for a successful biocontrol agent, these results indicate that the nonaflatoxigenic A. flavus strain WRRL 1519 would be a good candidate as a biocontrol agent for reducing aflatoxin and CPA accumulation in high-value nut crops.
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Affiliation(s)
- Guohua Yin
- a Department of Plant Biology, Rutgers , The State University of New Jersey , New Brunswick , New Jersey 08901.,b New Mexico Consortium and Pebble Labs , Los Alamos , New Mexico 87544
| | - Sui Sheng T Hua
- c Foodborne Toxin Detection and Prevention Research, Western Regional Research Center, Agricultural Research Service , US Department of Agriculture , Albany , California 94710
| | - Kayla K Pennerman
- a Department of Plant Biology, Rutgers , The State University of New Jersey , New Brunswick , New Jersey 08901
| | - Jiujiang Yu
- d Food Quality Laboratory, Agricultural Research Service , US Department of Agriculture, Beltsville Agricultural Research Center , Beltsville , Maryland 20705
| | - Lijing Bu
- e Center for Evolutionary & Theoretical Immunology, Department of Biology , University of New Mexico , Albuquerque , New Mexico 87131
| | - Richard T Sayre
- b New Mexico Consortium and Pebble Labs , Los Alamos , New Mexico 87544
| | - Joan W Bennett
- a Department of Plant Biology, Rutgers , The State University of New Jersey , New Brunswick , New Jersey 08901
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Aspergillus flavus Secondary Metabolites: More than Just Aflatoxins. Food Saf (Tokyo) 2018; 6:7-32. [PMID: 32231944 DOI: 10.14252/foodsafetyfscj.2017024] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 03/09/2018] [Indexed: 11/21/2022] Open
Abstract
Aspergillus flavus is best known for producing the family of potent carcinogenic secondary metabolites known as aflatoxins. However, this opportunistic plant and animal pathogen also produces numerous other secondary metabolites, many of which have also been shown to be toxic. While about forty of these secondary metabolites have been identified from A. flavus cultures, analysis of the genome has predicted the existence of at least 56 secondary metabolite gene clusters. Many of these gene clusters are not expressed during growth of the fungus on standard laboratory media. This presents researchers with a major challenge of devising novel strategies to manipulate the fungus and its genome so as to activate secondary metabolite gene expression and allow identification of associated cluster metabolites. In this review, we discuss the genetic, biochemical and bioinformatic methods that are being used to identify previously uncharacterized secondary metabolite gene clusters and their associated metabolites. It is important to identify as many of these compounds as possible to determine their bioactivity with respect to fungal development, survival, virulence and especially with respect to any potential synergistic toxic effects with aflatoxin.
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Ostry V, Toman J, Grosse Y, Malir F. Cyclopiazonic acid: 50th anniversary of its discovery. WORLD MYCOTOXIN J 2018. [DOI: 10.3920/wmj2017.2243] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In 1968, the mycotoxin cyclopiazonic acid (CPA) was first discovered and characterised as a chemical substance. Within the following five decades, much has been learned from the results of CPA research. CPA is produced by several Penicillium species (P. griseofulvum, P. camemberti, P. commune, P. dipodomyicola) and Aspergillus species (A. flavus, A. oryzae and A. tamarii). It is widespread on naturally contaminated agricultural raw materials. CPA has been reported to occur in food commodities (e.g. oilseeds, nuts, cereals, dried figs, milk, cheese and meat products) and to possess toxicological significance. CPA is also frequently detected in peanuts and maize; the presence of CPA and aflatoxins in maize and peanuts contaminated with A. flavus suggests that synergism may occur. CPA is toxic to several animal species, such as rats, pigs, guinea pigs, poultry and dogs. After ingesting CPA-contaminated feeds, test animals display severe gastrointestinal upsets and neurological disorders. Organs affected include the liver, kidney, heart, and digestive tract, which show degenerative changes and necrosis. Biologically, CPA is a specific inhibitor of sarco(endo)plasmic reticulum Ca2+-ATPase. Data from toxicological evaluation of aflatoxins and CPA in broiler chickens demonstrate that both aflatoxins and CPA alone and the aflatoxin-CPA combination can adversely affect broiler health. The effects of aflatoxins and CPA combination were additive in most cases.
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Affiliation(s)
- V. Ostry
- National Institute of Public Health, Centre for Health, Nutrition and Food, National Reference Centre for Microfungi and Mycotoxins in Food Chains, Palackeho 3a, 61242 Brno, Czech Republic
| | - J. Toman
- University of Hradec Kralove, Department of Biology, Faculty of Science, Rokitanskeho 62, 50003 Hradec Kralove, Czech Republic
| | - Y. Grosse
- International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon Cedex 08, France
| | - F. Malir
- University of Hradec Kralove, Department of Biology, Faculty of Science, Rokitanskeho 62, 50003 Hradec Kralove, Czech Republic
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46
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Bhatnagar D, Rajasekaran K, Gilbert M, Cary J, Magan N. Advances in molecular and genomic research to safeguard food and feed supply from aflatoxin contamination. WORLD MYCOTOXIN J 2018. [DOI: 10.3920/wmj2017.2283] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Worldwide recognition that aflatoxin contamination of agricultural commodities by the fungus Aspergillus flavus is a global problem has significantly benefitted from global collaboration for understanding the contaminating fungus, as well as for developing and implementing solutions against the contamination. The effort to address this serious food and feed safety issue has led to a detailed understanding of the taxonomy, ecology, physiology, genomics and evolution of A. flavus, as well as strategies to reduce or control pre-harvest aflatoxin contamination, including (1) biological control, using atoxigenic aspergilli, (2) proteomic and genomic analyses for identifying resistance factors in maize as potential breeding markers to enable development of resistant maize lines, and (3) enhancing host-resistance by bioengineering of susceptible crops, such as cotton, maize, peanut and tree nuts. A post-harvest measure to prevent the occurrence of aflatoxin contamination in storage is also an important component for reducing exposure of populations worldwide to aflatoxins in food and feed supplies. The effect of environmental changes on aflatoxin contamination levels has recently become an important aspect for study to anticipate future contamination levels. The ability of A. flavus to produce dozens of secondary metabolites, in addition to aflatoxins, has created a new avenue of research for understanding the role these metabolites play in the survival and biodiversity of this fungus. The understanding of A. flavus, the aflatoxin contamination problem, and control measures to prevent the contamination has become a unique example for an integrated approach to safeguard global food and feed safety.
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Affiliation(s)
- D. Bhatnagar
- US Department of Agriculture, Agricultural Research Service, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA
| | - K. Rajasekaran
- US Department of Agriculture, Agricultural Research Service, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA
| | - M. Gilbert
- US Department of Agriculture, Agricultural Research Service, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA
| | - J.W. Cary
- US Department of Agriculture, Agricultural Research Service, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA
| | - N. Magan
- Applied Mycology Group, Cranfield University, MK45 4DT, Cranfield, United Kingdom
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47
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Fountain JC, Koh J, Yang L, Pandey MK, Nayak SN, Bajaj P, Zhuang WJ, Chen ZY, Kemerait RC, Lee RD, Chen S, Varshney RK, Guo B. Proteome analysis of Aspergillus flavus isolate-specific responses to oxidative stress in relationship to aflatoxin production capability. Sci Rep 2018; 8:3430. [PMID: 29467403 PMCID: PMC5821837 DOI: 10.1038/s41598-018-21653-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 02/03/2018] [Indexed: 12/24/2022] Open
Abstract
Aspergillus flavus is an opportunistic pathogen of plants such as maize and peanut under conducive conditions such as drought stress resulting in significant aflatoxin production. Drought-associated oxidative stress also exacerbates aflatoxin production by A. flavus. The objectives of this study were to use proteomics to provide insights into the pathogen responses to H2O2-derived oxidative stress, and to identify potential biomarkers and targets for host resistance breeding. Three isolates, AF13, NRRL3357, and K54A with high, moderate, and no aflatoxin production, were cultured in medium supplemented with varying levels of H2O2, and examined using an iTRAQ (Isobaric Tags for Relative and Absolute Quantification) approach. Overall, 1,173 proteins were identified and 220 were differentially expressed (DEPs). Observed DEPs encompassed metabolic pathways including antioxidants, carbohydrates, pathogenicity, and secondary metabolism. Increased lytic enzyme, secondary metabolite, and developmental pathway expression in AF13 was correlated with oxidative stress tolerance, likely assisting in plant infection and microbial competition. Elevated expression of energy and cellular component production in NRRL3357 and K54A implies a focus on oxidative damage remediation. These trends explain isolate-to-isolate variation in oxidative stress tolerance and provide insights into mechanisms relevant to host plant interactions under drought stress allowing for more targeted efforts in host resistance research.
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Affiliation(s)
- Jake C Fountain
- Department of Plant Pathology, University of Georgia, Tifton, GA, USA.,USDA-ARS Crop Protection and Management Research Unit, Tifton, GA, USA.,Center of Excellence in Genomics & Systems Biology, International Crop Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Telangana, India
| | - Jin Koh
- Department of Biology, Genetics Institute, Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL, USA
| | - Liming Yang
- Department of Plant Pathology, University of Georgia, Tifton, GA, USA.,USDA-ARS Crop Protection and Management Research Unit, Tifton, GA, USA.,College of Biology and Environmental Science, Nanjing Forestry University, Nanjing, China
| | - Manish K Pandey
- Center of Excellence in Genomics & Systems Biology, International Crop Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Telangana, India
| | - Spurthi N Nayak
- Center of Excellence in Genomics & Systems Biology, International Crop Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Telangana, India
| | - Prasad Bajaj
- Center of Excellence in Genomics & Systems Biology, International Crop Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Telangana, India
| | - Wei-Jian Zhuang
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Zhi-Yuan Chen
- Department of Plant Pathology and Crop Physiology, Louisiana State University, Baton Rouge, LA, USA
| | - Robert C Kemerait
- Department of Plant Pathology, University of Georgia, Tifton, GA, USA
| | - R Dewey Lee
- Department of Crop and Soil Sciences, University of Georgia, Tifton, GA, USA
| | - Sixue Chen
- Department of Biology, Genetics Institute, Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, FL, USA
| | - Rajeev K Varshney
- Center of Excellence in Genomics & Systems Biology, International Crop Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, Telangana, India
| | - Baozhu Guo
- USDA-ARS Crop Protection and Management Research Unit, Tifton, GA, USA.
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Zhurakovskyi O, Türkmen YE, Löffler LE, Moorthie VA, Chen CC, Shaw MA, Crimmin MR, Ferrara M, Ahmad M, Ostovar M, Matlock JV, Aggarwal VK. Enantioselective Synthesis of the Cyclopiazonic Acid Family Using Sulfur Ylides. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201712065] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
| | - Yunus E. Türkmen
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
| | - Lorenz E. Löffler
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
| | | | - C. Chun Chen
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
| | - Michael A. Shaw
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
| | - Mark R. Crimmin
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
| | - Marco Ferrara
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
| | - Mushtaq Ahmad
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
| | - Mehrnoosh Ostovar
- School of Chemistry; University of Bristol; Cantock's Close Bristol BS8 1TS UK
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Alassane-Kpembi I, Schatzmayr G, Taranu I, Marin D, Puel O, Oswald IP. Mycotoxins co-contamination: Methodological aspects and biological relevance of combined toxicity studies. Crit Rev Food Sci Nutr 2018; 57:3489-3507. [PMID: 26918653 DOI: 10.1080/10408398.2016.1140632] [Citation(s) in RCA: 165] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Mycotoxins are secondary fungal metabolites produced mainly by Aspergillus, Penicillium, and Fusarium. As evidenced by large-scale surveys, humans and animals are simultaneously exposed to several mycotoxins. Simultaneous exposure could result in synergistic, additive or antagonistic effects. However, most toxicity studies addressed the effects of mycotoxins separately. We present the experimental designs and we discuss the conclusions drawn from in vitro experiments exploring toxicological interactions of mycotoxins. We report more than 80 publications related to mycotoxin interactions. The studies explored combinations involving the regulated groups of mycotoxins, especially aflatoxins, ochratoxins, fumonisins, zearalenone and trichothecenes, but also the "emerging" mycotoxins beauvericin and enniatins. Over 50 publications are based on the arithmetic model of additivity. Few studies used the factorial designs or the theoretical biology-based models of additivity. The latter approaches are gaining increased attention. These analyses allow determination of the type of interaction and, optionally, its magnitude. The type of interaction reported for mycotoxin combinations depended on several factors, in particular cell models and the tested dose ranges. However, synergy among Fusarium toxins was highlighted in several studies. This review indicates that well-addressed in vitro studies remain valuable tools for the screening of interactive potential in mycotoxin mixtures.
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Affiliation(s)
- Imourana Alassane-Kpembi
- a Toxalim , Research Centre in Food Toxicology Université de Toulouse, INRA, ENVT, INP- PURPAN, UPS , Toulouse , France.,b Hôpital d'Instruction des Armées Camp Guézo , Cotonou , Bénin
| | | | - Ionelia Taranu
- d National Institute for Research and Development in Animal Biology and Nutrition (IBNA), Calea Bucuresti , Balotesti , Romania
| | - Daniela Marin
- d National Institute for Research and Development in Animal Biology and Nutrition (IBNA), Calea Bucuresti , Balotesti , Romania
| | - Olivier Puel
- a Toxalim , Research Centre in Food Toxicology Université de Toulouse, INRA, ENVT, INP- PURPAN, UPS , Toulouse , France
| | - Isabelle Paule Oswald
- a Toxalim , Research Centre in Food Toxicology Université de Toulouse, INRA, ENVT, INP- PURPAN, UPS , Toulouse , France
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50
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Zhurakovskyi O, Türkmen YE, Löffler LE, Moorthie VA, Chen CC, Shaw MA, Crimmin MR, Ferrara M, Ahmad M, Ostovar M, Matlock JV, Aggarwal VK. Enantioselective Synthesis of the Cyclopiazonic Acid Family Using Sulfur Ylides. Angew Chem Int Ed Engl 2018; 57:1346-1350. [PMID: 29265694 PMCID: PMC5817397 DOI: 10.1002/anie.201712065] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Indexed: 12/17/2022]
Abstract
A convergent, nine‐step (LLS), enantioselective synthesis of α‐cyclopiazonic acid and related natural products is reported. The route features a) an enantioselective aziridination of an imine with a chiral sulfur ylide; b) a bioinspired (3+2)‐cycloaddition of the aziridine onto an alkene; and c) installation of the acetyltetramic acid by an unprecedented tandem carbonylative lactamization/N−O cleavage of a bromoisoxazole.
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Affiliation(s)
| | - Yunus E Türkmen
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Lorenz E Löffler
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | | | - C Chun Chen
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Michael A Shaw
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Mark R Crimmin
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Marco Ferrara
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Mushtaq Ahmad
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Mehrnoosh Ostovar
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Johnathan V Matlock
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
| | - Varinder K Aggarwal
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK
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