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McHenry DJ, Aćimović SG. New Species-Specific Real-Time PCR Assays for Colletotrichum Species Causing Bitter Rot of Apple. Microorganisms 2024; 12:878. [PMID: 38792708 PMCID: PMC11123832 DOI: 10.3390/microorganisms12050878] [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: 02/28/2024] [Revised: 04/17/2024] [Accepted: 04/23/2024] [Indexed: 05/26/2024] Open
Abstract
Bitter rot of apple is an economically important worldwide disease caused by different Colletotrichum species, depending on many factors such as climate, geography, other hosts, and crop management practices. Culture, morphology, and single-locus sequencing-based methods for identifying the Colletotrichum species are severely limited in effectiveness, while the multilocus sequence typing methods available for delineating species are costly, time-intensive, and require high expertise. We developed species-specific hydrolysis probe real-time PCR assays for the following nine Colletotrichum species causing bitter rot in the Mid-Atlantic U.S.A.: C. fructicola, C. chrysophilum, C. noveboracense, C. gloeosporioides s.s., C. henanense, C. siamense and C. theobromicola from the C. gloeosporioides species complex, and C. fioriniae and C. nymphaeae from the C. acutatum species complex. After searching 14 gene regions, we designed primers and probes in 5 of them for the nine target species. Four primer-probe set pairs were able to be duplexed. Sensitivity tests showed as little as 0.5 pg DNA were detectable. These real-time PCR assays will provide rapid and reliable identification of these key Colletotrichum species and will be critically important for studies aiming to elucidate their biology, epidemiology, and management on apples as the number one produced and consumed tree fruit in the U.S.A.
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Affiliation(s)
| | - Srđan G. Aćimović
- Plant Pathology Laboratory, Alson H. Smith Jr. Agricultural Research and Extension Center, School of Plant and Environmental Sciences, Virginia Polytechnic Institute and State University, Winchester, VA 22602, USA
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2
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Ahmad N, Ritz M, Calchera A, Otte J, Schmitt I, Brueck T, Mehlmer N. Biosynthetic gene cluster synteny: Orthologous polyketide synthases in Hypogymnia physodes, Hypogymnia tubulosa, and Parmelia sulcata. Microbiologyopen 2023; 12:e1386. [PMID: 37877655 PMCID: PMC10582450 DOI: 10.1002/mbo3.1386] [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: 08/03/2023] [Revised: 09/15/2023] [Accepted: 09/26/2023] [Indexed: 10/26/2023] Open
Abstract
Lichens are symbiotic associations consisting of a photobiont (algae or cyanobacteria) and a mycobiont (fungus), which together generate a variety of unique secondary metabolites. To access this biosynthetic potential for biotechnological applications, deeper insights into the biosynthetic pathways and corresponding gene clusters are necessary. Here, we provide a comparative view of the biosynthetic gene clusters of three lichen mycobionts derived from Hypogymnia physodes, Hypogymnia tubulosa, and Parmelia sulcata. In addition, we present a high-quality PacBio metagenome of Parmelia sulcata, from which we extracted the mycobiont bin containing 214 biosynthetic gene clusters. Most biosynthetic gene clusters in these genomes were associated with T1PKSs, followed by NRPSs and terpenes. This study focused on biosynthetic gene clusters related to polyketide synthesis. Based on ketosynthase homology, we identified nine highly syntenic clusters present in all three species. Among the four clusters belonging to nonreducing PKSs, two are putatively linked to lichen substances derived from orsellinic acid (orcinol depsides and depsidones, e.g., lecanoric acid, physodic acid, lobaric acid), one to compounds derived from methylated forms of orsellinic acid (beta orcinol depsides, e.g., atranorin), and one to melanins. Five clusters with orthologs in all three species are linked to reducing PKSs. Our study contributes to sorting and dereplicating the vast PKS diversity found in lichenized fungi. High-quality sequences of biosynthetic gene clusters of these three common species provide a foundation for further exploration into biotechnological applications and the molecular evolution of lichen substances.
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Affiliation(s)
- Nadim Ahmad
- Department of Chemistry, Werner Siemens Chair of Synthetic Biotechnology, TUM School of Natural SciencesTechnical University of Munich (TUM)GarchingGermany
| | - Manfred Ritz
- Department of Chemistry, Werner Siemens Chair of Synthetic Biotechnology, TUM School of Natural SciencesTechnical University of Munich (TUM)GarchingGermany
| | - Anjuli Calchera
- Senckenberg Biodiversity and Climate Research Centre (SBiK‐F)Frankfurt am MainGermany
| | - Jürgen Otte
- Senckenberg Biodiversity and Climate Research Centre (SBiK‐F)Frankfurt am MainGermany
| | - Imke Schmitt
- Senckenberg Biodiversity and Climate Research Centre (SBiK‐F)Frankfurt am MainGermany
- Institute of Ecology, Evolution and DiversityGoethe University FrankfurtFrankfurt am MainGermany
| | - Thomas Brueck
- Department of Chemistry, Werner Siemens Chair of Synthetic Biotechnology, TUM School of Natural SciencesTechnical University of Munich (TUM)GarchingGermany
| | - Norbert Mehlmer
- Department of Chemistry, Werner Siemens Chair of Synthetic Biotechnology, TUM School of Natural SciencesTechnical University of Munich (TUM)GarchingGermany
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3
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Wang P, Park HS, Wang W, Yin WB. Editorial: Gene regulation of fungal secondary metabolism. Front Microbiol 2023; 14:1260849. [PMID: 37655343 PMCID: PMC10466026 DOI: 10.3389/fmicb.2023.1260849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 08/07/2023] [Indexed: 09/02/2023] Open
Affiliation(s)
- Pinmei Wang
- Ocean College, Zhejiang University, Zhoushan, China
| | - Hee-Soo Park
- School of Food Science and Biotechnology, Kyungpook National University, Daegu, Republic of Korea
| | - Wenjie Wang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, China
| | - Wen-Bing Yin
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
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4
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Nickles GR, Oestereicher B, Keller NP, Drott M. Mining for a new class of fungal natural products: the evolution, diversity, and distribution of isocyanide synthase biosynthetic gene clusters. Nucleic Acids Res 2023; 51:7220-7235. [PMID: 37427794 PMCID: PMC10415135 DOI: 10.1093/nar/gkad573] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/16/2023] [Accepted: 07/06/2023] [Indexed: 07/11/2023] Open
Abstract
The products of non-canonical isocyanide synthase (ICS) biosynthetic gene clusters (BGCs) mediate pathogenesis, microbial competition, and metal-homeostasis through metal-associated chemistry. We sought to enable research into this class of compounds by characterizing the biosynthetic potential and evolutionary history of these BGCs across the Fungal Kingdom. We amalgamated a pipeline of tools to predict BGCs based on shared promoter motifs and located 3800 ICS BGCs in 3300 genomes, making ICS BGCs the fifth largest class of specialized metabolites compared to canonical classes found by antiSMASH. ICS BGCs are not evenly distributed across fungi, with evidence of gene-family expansions in several Ascomycete families. We show that the ICS dit1/2 gene cluster family (GCF), which was prior only studied in yeast, is present in ∼30% of all Ascomycetes. The dit variety ICS exhibits greater similarity to bacterial ICS than other fungal ICS, suggesting a potential convergence of the ICS backbone domain. The evolutionary origins of the dit GCF in Ascomycota are ancient and these genes are diversifying in some lineages. Our results create a roadmap for future research into ICS BGCs. We developed a website (https://isocyanides.fungi.wisc.edu/) that facilitates the exploration and downloading of all identified fungal ICS BGCs and GCFs.
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Affiliation(s)
- Grant R Nickles
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, WI 53706, USA
| | | | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, WI 53706, USA
- Department of Plant Pathology, University of Wisconsin—Madison, Madison, WI 53706, USA
| | - Milton T Drott
- USDA-ARS Cereal Disease Lab (CDL), St. Paul, MN 55108, USA
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5
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Zhgun AA. Fungal BGCs for Production of Secondary Metabolites: Main Types, Central Roles in Strain Improvement, and Regulation According to the Piano Principle. Int J Mol Sci 2023; 24:11184. [PMID: 37446362 PMCID: PMC10342363 DOI: 10.3390/ijms241311184] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 06/28/2023] [Accepted: 07/03/2023] [Indexed: 07/15/2023] Open
Abstract
Filamentous fungi are one of the most important producers of secondary metabolites. Some of them can have a toxic effect on the human body, leading to diseases. On the other hand, they are widely used as pharmaceutically significant drugs, such as antibiotics, statins, and immunosuppressants. A single fungus species in response to various signals can produce 100 or more secondary metabolites. Such signaling is possible due to the coordinated regulation of several dozen biosynthetic gene clusters (BGCs), which are mosaically localized in different regions of fungal chromosomes. Their regulation includes several levels, from pathway-specific regulators, whose genes are localized inside BGCs, to global regulators of the cell (taking into account changes in pH, carbon consumption, etc.) and global regulators of secondary metabolism (affecting epigenetic changes driven by velvet family proteins, LaeA, etc.). In addition, various low-molecular-weight substances can have a mediating effect on such regulatory processes. This review is devoted to a critical analysis of the available data on the "turning on" and "off" of the biosynthesis of secondary metabolites in response to signals in filamentous fungi. To describe the ongoing processes, the model of "piano regulation" is proposed, whereby pressing a certain key (signal) leads to the extraction of a certain sound from the "musical instrument of the fungus cell", which is expressed in the production of a specific secondary metabolite.
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Affiliation(s)
- Alexander A Zhgun
- Group of Fungal Genetic Engineering, Federal Research Center "Fundamentals of Biotechnology", Russian Academy of Sciences, Leninsky Prosp. 33-2, 119071 Moscow, Russia
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6
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Nickles GR, Oestereicher B, Keller NP, Drott MT. Mining for a New Class of Fungal Natural Products: The Evolution, Diversity, and Distribution of Isocyanide Synthase Biosynthetic Gene Clusters. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.17.537281. [PMID: 37131656 PMCID: PMC10153163 DOI: 10.1101/2023.04.17.537281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The products of non-canonical isocyanide synthase (ICS) biosynthetic gene clusters (BGCs) have notable bioactivities that mediate pathogenesis, microbial competition, and metal-homeostasis through metal-associated chemistry. We sought to enable research into this class of compounds by characterizing the biosynthetic potential and evolutionary history of these BGCs across the Fungal Kingdom. We developed the first genome-mining pipeline to identify ICS BGCs, locating 3,800 ICS BGCs in 3,300 genomes. Genes in these clusters share promoter motifs and are maintained in contiguous groupings by natural selection. ICS BGCs are not evenly distributed across fungi, with evidence of gene-family expansions in several Ascomycete families. We show that the ICS dit1 / 2 gene cluster family (GCF), which was thought to only exist in yeast, is present in ∼30% of all Ascomycetes, including many filamentous fungi. The evolutionary history of the dit GCF is marked by deep divergences and phylogenetic incompatibilities that raise questions about convergent evolution and suggest selection or horizontal gene transfers have shaped the evolution of this cluster in some yeast and dimorphic fungi. Our results create a roadmap for future research into ICS BGCs. We developed a website ( www.isocyanides.fungi.wisc.edu ) that facilitates the exploration, filtering, and downloading of all identified fungal ICS BGCs and GCFs.
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Affiliation(s)
- Grant R. Nickles
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, WI 53706, USA
| | | | - Nancy P. Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, WI 53706, USA
- Department of Plant Pathology, University of Wisconsin—Madison, Madison, WI 53706, USA
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7
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Yang Z, Liu H, Su Z, Xu H, Yuan Z, Rao Y. Enhanced production of aspochalasin D through genetic engineering of Aspergillus flavipes. Appl Microbiol Biotechnol 2023; 107:2911-2920. [PMID: 37004567 DOI: 10.1007/s00253-023-12501-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/09/2023] [Accepted: 03/23/2023] [Indexed: 04/04/2023]
Abstract
Aspochalasin D (AD) belongs to the polyketide-amino acid hybrid natural products with anti-cancer, anti-bacterial, and anti-fouling bioactivities. However, the low production limits its further application. In this study, AD was separated and identified from Aspergillus flavipes 3.17641. Next, besides the optimization of culture conditions using a single-factor experiment and response surface methodology, metabolic engineering was employed to increase the AD production. It shows that the deletion of the shunt gene aspoA and overexpression of the pathway-specific regulator aspoG significantly improve the AD production. Its production reached to 812.1 mg/L under the optimized conditions, with 18.5-fold increase. Therefore, this study not only provides a general method for improving the production of similar natural products in other fungi, but also enables the further biological function development of AD in agriculture and pharmaceutical. KEY POINTS: • The Aspochalasin D (AD) production was improved by optimizing culture conditions. • The deletion of the shunt gene aspoA increased the AD production. • Overexpression of the pathway regulator aspoG further improved the AD production.
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Affiliation(s)
- Zhaopeng Yang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Huiling Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Zengping Su
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Huibin Xu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Zhenbo Yuan
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China
| | - Yijian Rao
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.
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8
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Wang W, Liang X, Li Y, Wang P, Keller NP. Genetic Regulation of Mycotoxin Biosynthesis. J Fungi (Basel) 2022; 9:jof9010021. [PMID: 36675842 PMCID: PMC9861139 DOI: 10.3390/jof9010021] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 12/20/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022] Open
Abstract
Mycotoxin contamination in food poses health hazards to humans. Current methods of controlling mycotoxins still have limitations and more effective approaches are needed. During the past decades of years, variable environmental factors have been tested for their influence on mycotoxin production leading to elucidation of a complex regulatory network involved in mycotoxin biosynthesis. These regulators are putative targets for screening molecules that could inhibit mycotoxin synthesis. Here, we summarize the regulatory mechanisms of hierarchical regulators, including pathway-specific regulators, global regulators and epigenetic regulators, on the production of the most critical mycotoxins (aflatoxins, patulin, citrinin, trichothecenes and fumonisins). Future studies on regulation of mycotoxins will provide valuable knowledge for exploring novel methods to inhibit mycotoxin biosynthesis in a more efficient way.
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Affiliation(s)
- Wenjie Wang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
- Institute of Food Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
- Correspondence: (W.W.); (N.P.K.)
| | - Xinle Liang
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
- Institute of Food Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Yudong Li
- School of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
- Institute of Food Biotechnology, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Pinmei Wang
- Ocean College, Zhejiang University, Zhoushan 316021, China
| | - Nancy P. Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
- Correspondence: (W.W.); (N.P.K.)
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9
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The Hydrophobin Gene Family Confers a Fitness Trade-off between Spore Dispersal and Host Colonization in Penicillium expansum. mBio 2022; 13:e0275422. [PMID: 36374077 PMCID: PMC9765440 DOI: 10.1128/mbio.02754-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Hydrophobins are small amphipathic surface proteins found exclusively in fungi. In filamentous ascomycetes, one conserved role of a subset of hydrophobins is their requirement for spore dispersal. Other contributions of these proteins to fungal biology are less clear and vary across genera. To determine the functions of hydrophobins in the biology and virulence of this fungus, we created seven single mutants and a septuple-deletion mutant (Δsep) of the entire putative P. expansum hydrophobin gene family. One spore hydrophobin, HfbA, shared 72.56% sequence identity to the Aspergillus fumigatus spore hydrophobin RodA and was required for efficient spore dispersion in P. expansum. The Δsep mutant was likewise reduced in spore dispersal, hypothesized to be due to the aberrant shape and clumping of the Δsep conidia and conidiophores. Additionally, the Δsep mutant presented several differences in physiological traits, including decreased survival in extreme cold temperatures and increased production of several toxic secondary metabolites. Most striking was the unexpected fitness advantage that the Δsep strain displayed in competitive passaging with the wild-type strain on host apple where the mutant significantly increased in percentage of the colonizing population. This work uncovers potential ecological trade-offs of hydrophobin presence in filamentous fungi. IMPORTANCE Hydrophobins are amphipathic secreted proteins uniquely found in filamentous fungi. These proteins self-assemble and constitute the outer most layer of fungal surfaces thus mediating multiple aspects of fungal interactions with their environments. Hydrophobins facilitate spore dispersal, yet a full understanding of the function and need for multiple hydrophobins in fungal species remains elusive. To address the role of this protein family in Penicillium expansum, the causative agent of blue mold disease in pome fruit, all seven putative hydrophobin genes were deleted and the mutant assessed for numerous physiological traits and virulence on fruit. Despite showing a decrease in spore dispersal, the septuple-deletion mutant was more fit than the wild type in competitive pathogenicity tests on apple. Our findings suggest this gene family illustrates a functional trade-off between dispersal and host colonization in P. expansum.
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Ferrara M, Perrone G, Gallo A. Recent advances in biosynthesis and regulatory mechanisms of principal mycotoxins. Curr Opin Food Sci 2022. [DOI: 10.1016/j.cofs.2022.100923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Expression of citrinin biosynthesis gene in Liupao tea and effect of Penicillium citrinum on tea quality. Fungal Genet Biol 2022; 163:103742. [PMID: 36108886 DOI: 10.1016/j.fgb.2022.103742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 08/19/2022] [Accepted: 09/08/2022] [Indexed: 01/06/2023]
Abstract
Similar to Pu-erh tea, Liupao tea is a post-fermented tea that is produced through natural fermentation by microorganisms. Penicillium citrinum is involved in multiple production processes of Liupao tea that can produce citrinin, a secondary metabolite with renal toxicity; however, the effect of P. citrinum on the quality of Liupao tea has not been investigated yet. Citrinin production is regulated by approximately 16 biosynthesis genes. However, little is known about the genetic background of citrinin in the complex Liupao tea system. In the present study, we cultured P. citrinum on potato dextrose agar and Liupao tea powder media and analyzed the changes of its nutritional components in Liupao tea. We selected six citrinin biosynthesis genes identified in Monascus exhibiting homology and high sequence similarity to those in P. citrinum and further analyzed the expression of citrinin biosynthesis genes in Liupao tea and the changes in citrinin yield. The results showed that the changes in nutritional components of Liupao tea were closely related to the growth and metabolism of P. citrinum and the quality of the tea. Decreases in the contents of soluble sugars (from 10.29% to 9.58%), soluble pectins (from 3.71% to 3.13%), free amino acids (from 3.84% to 3.14%), and tea polyphenols (from 22.84% to 18.78%) were noted. The Spearman's correlation analysis indicated that P. citrinum growth can improve the tea quality to some extent. Quantitative real-time PCR demonstrated that ctnA gene was a positive regulator of citrinin production regardless of the culture medium used. ctnA and orf5 expressions greatly influenced the metabolism of citrinin by P. citrinum in Liupao tea. In conclusion, the citrinin biosynthesis genes, ctnA and orf5, may be the promising targets for developing strategies to control P. citrinum infection and citrinin biosynthesis in Liupao tea.
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12
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Quantitative characterization of filamentous fungal promoters on a single-cell resolution to discover cryptic natural products. SCIENCE CHINA LIFE SCIENCES 2022; 66:848-860. [PMID: 36287342 DOI: 10.1007/s11427-022-2175-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 08/15/2022] [Indexed: 11/05/2022]
Abstract
Characterization of filamentous fungal regulatory elements remains challenging because of time-consuming transformation technologies and limited quantitative methods. Here we established a method for quantitative assessment of filamentous fungal promoters based on flow cytometry detection of the superfolder green fluorescent protein at single-cell resolution. Using this quantitative method, we acquired a library of 93 native promoter elements from Aspergillus nidulans in a high-throughput format. The strengths of identified promoters covered a 37-fold range by flow cytometry. PzipA and PsltA were identified as the strongest promoters, which were 2.9- and 1.5-fold higher than that of the commonly used constitutive promoter PgpdA. Thus, we applied PzipA and PsltA to activate the silent nonribosomal peptide synthetase gene Afpes1 from Aspergillus fumigatus in its native host and the heterologous host A. nidulans. The metabolic products of Afpes1 were identified as new cyclic tetrapeptide derivatives, namely, fumiganins A and B. Our method provides an innovative strategy for natural product discovery in fungi.
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13
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Chen L, Wang XN, Bi HY, Wang GY. Antimicrobial Biosynthetic Potential and Phylogenetic Analysis of Culturable Bacteria Associated with the Sponge Ophlitaspongia sp. from the Yellow Sea, China. Mar Drugs 2022; 20:md20100588. [PMID: 36286412 PMCID: PMC9605435 DOI: 10.3390/md20100588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 09/13/2022] [Accepted: 09/16/2022] [Indexed: 11/25/2022] Open
Abstract
Sponge-derived bacteria are considered to be a promising source of novel drugs, owing to their abundant secondary metabolites that have diverse biological activities. In this study, we explored the antimicrobial biosynthetic potential and phylogenetics of culturable bacteria associated with the sponge Ophlitaspongia sp. from the Yellow Sea, China. Using culture-dependent methods, we obtained 151 bacterial strains, which were then analysed for their antimicrobial activities against seven indicator strains. The results indicate that 94 (62.3%) of the 151 isolated strains exhibited antimicrobial activities and inhibited at least one of the indicator strains. Fifty-two strains were selected for further phylogenetic analysis using 16S rRNA gene sequencing, as well as for the presence of polyketide synthase (PKS) and non-ribosomal peptide synthetase (NRPS) genes. These 52 strains belonged to 20 genera from 18 families in 4 phyla, including Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. Five strains with PKS genes and ten strains with NRPS genes were detected. Among them, two strains contained both PKS and NRPS genes. Notoacmeibacter sp. strain HMA008 (class Alphaproteobacteria) exhibited potent antimicrobial activity; thus, whole genome sequencing methods were used to analyse its secondary metabolite biosynthetic gene clusters. The genome of HMA008 contained 12 biosynthetic gene clusters that potentially encode secondary metabolites belonging to compound classes such as non-ribosomal peptides, prodigiosin, terpene, β-lactones, and siderophore, among others. This study indicates that the sponge Ophlitaspongia sp. harbours diverse bacterial strains with antimicrobial properties and may serve as a potential source of bioactive compounds.
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Affiliation(s)
- Lei Chen
- Department of Bioengineering, School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai 264209, China
- Correspondence: (L.C.); (G.-Y.W.)
| | - Xue-Ning Wang
- Shanghai Center for Systems Biomedicine, Key Laboratory of Systems Biomedicine (Ministry of Education), Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hong-Yu Bi
- Department of Bioengineering, School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai 264209, China
| | - Guang-Yu Wang
- Department of Bioengineering, School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai 264209, China
- Correspondence: (L.C.); (G.-Y.W.)
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14
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Schüller A, Studt-Reinhold L, Strauss J. How to Completely Squeeze a Fungus-Advanced Genome Mining Tools for Novel Bioactive Substances. Pharmaceutics 2022; 14:1837. [PMID: 36145585 PMCID: PMC9505985 DOI: 10.3390/pharmaceutics14091837] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/23/2022] [Accepted: 08/29/2022] [Indexed: 11/17/2022] Open
Abstract
Fungal species have the capability of producing an overwhelming diversity of bioactive substances that can have beneficial but also detrimental effects on human health. These so-called secondary metabolites naturally serve as antimicrobial "weapon systems", signaling molecules or developmental effectors for fungi and hence are produced only under very specific environmental conditions or stages in their life cycle. However, as these complex conditions are difficult or even impossible to mimic in laboratory settings, only a small fraction of the true chemical diversity of fungi is known so far. This also implies that a large space for potentially new pharmaceuticals remains unexplored. We here present an overview on current developments in advanced methods that can be used to explore this chemical space. We focus on genetic and genomic methods, how to detect genes that harbor the blueprints for the production of these compounds (i.e., biosynthetic gene clusters, BGCs), and ways to activate these silent chromosomal regions. We provide an in-depth view of the chromatin-level regulation of BGCs and of the potential to use the CRISPR/Cas technology as an activation tool.
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Affiliation(s)
| | | | - Joseph Strauss
- Institute of Microbial Genetics, Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences Vienna, A-3430 Tulln/Donau, Austria
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15
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Nickles G, Ludwikoski I, Bok JW, Keller NP. Comprehensive Guide to Extracting and Expressing Fungal Secondary Metabolites with Aspergillus fumigatus as a Case Study. Curr Protoc 2021; 1:e321. [PMID: 34958718 DOI: 10.1002/cpz1.321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Fungal secondary metabolites (SMs) have captured the interest of natural products researchers in academia and industry for decades. In recent years, the high rediscovery rate of previously characterized metabolites is making it increasingly difficult to uncover novel compounds. Additionally, the vast majority of fungal SMs reside in genetically intractable fungi or are silent under normal laboratory conditions in genetically tractable fungi. The fungal natural products community has broadly overcome these barriers by altering the physical growth conditions of the fungus and heterologous/homologous expression of biosynthetic gene cluster regulators or proteins. The protocols described here summarize vital methodologies needed when researching SM production in fungi. We also summarize the growth conditions, genetic backgrounds, and extraction protocols for every published SM in Aspergillus fumigatus, enabling readers to easily replicate the production of previously characterized SMs. Readers will also be equipped with the tools for developing their own strategy for expressing and extracting SMs from their given fungus or a suitable heterologous model system. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Making glycerol stocks from spore suspensions Alternate Protocol 1: Creating glycerol stocks from non-sporulating filamentous fungi Basic Protocol 2: Activating spore-suspension glycerol stocks Basic Protocol 3: Extracting secondary metabolites from Aspergillus spp grown on solid medium Alternate Protocol 2: Extracting secondary metabolites from Aspergillus spp using ethyl acetate Alternate Protocol 3: High-volume metabolite extraction using ethyl acetate Alternate Protocol 4: Extracting secondary metabolites from Aspergillus spp in liquid medium Support Protocol: Creating an overlay culture Basic Protocol 4: Extracting DNA from filamentous fungi Basic Protocol 5: Creating a DNA construct with double-joint PCR Alternate Protocol 5: Creating a DNA construct with yeast recombineering Basic Protocol 6: Transformation of Aspergillus spp Basic Protocol 7: Co-culturing fungi and bacteria for extraction of secondary metabolites.
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Affiliation(s)
- Grant Nickles
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Isabelle Ludwikoski
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Jin Woo Bok
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin.,Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin
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Wang W, Yu Y, Keller NP, Wang P. Presence, Mode of Action, and Application of Pathway Specific Transcription Factors in Aspergillus Biosynthetic Gene Clusters. Int J Mol Sci 2021; 22:ijms22168709. [PMID: 34445420 PMCID: PMC8395729 DOI: 10.3390/ijms22168709] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 08/10/2021] [Accepted: 08/10/2021] [Indexed: 01/21/2023] Open
Abstract
Fungal secondary metabolites are renowned toxins as well as valuable sources of antibiotics, cholesterol-lowering drugs, and immunosuppressants; hence, great efforts were levied to understand how these compounds are genetically regulated. The genes encoding for the enzymes required for synthesizing secondary metabolites are arranged in biosynthetic gene clusters (BGCs). Often, BGCs contain a pathway specific transcription factor (PSTF), a valuable tool in shutting down or turning up production of the BGC product. In this review, we present an in-depth view of PSTFs by examining over 40 characterized BGCs in the well-studied fungal species Aspergillus nidulans and Aspergillus fumigatus. Herein, we find BGC size is a predictor for presence of PSTFs, consider the number and the relative location of PSTF in regard to the cluster(s) regulated, discuss the function and the evolution of PSTFs, and present application strategies for pathway specific activation of cryptic BGCs.
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Affiliation(s)
- Wenjie Wang
- Ocean College, Zhejiang University, Zhoushan 316021, China; (W.W.); (Y.Y.)
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Yuchao Yu
- Ocean College, Zhejiang University, Zhoushan 316021, China; (W.W.); (Y.Y.)
| | - Nancy P. Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI 53706, USA
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
- Correspondence: (N.P.K.); (P.W.)
| | - Pinmei Wang
- Ocean College, Zhejiang University, Zhoushan 316021, China; (W.W.); (Y.Y.)
- Correspondence: (N.P.K.); (P.W.)
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