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Liu Z, Ma K, Zhang X, Song X, Qin Y. Different Putative Methyltransferases Have Different Effects on the Expression Patterns of Cellulolytic Genes. J Fungi (Basel) 2023; 9:1118. [PMID: 37998923 PMCID: PMC10671955 DOI: 10.3390/jof9111118] [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: 10/10/2023] [Revised: 11/07/2023] [Accepted: 11/16/2023] [Indexed: 11/25/2023] Open
Abstract
Putative methyltranferase LaeA and LaeA-like proteins, conserved in many filamentous fungi, regulate fungal growth, development, virulence, the biosynthesis of secondary metabolites, and the production of cellulolytic enzymes. Penicillium oxaliucm is a typical fungus that produces cellulolytic enzymes. In this study, we reported the biological function of eight putative methyltransferases (PoMtr23C/D/E/F/G/H and PoMtr25A/B) containing a methyltransf_23 or methyltransf_25 domain, with a focus on their roles in the production of cellulolytic enzymes. In P. oxalicum, various methyltransferase genes displayed different transcriptional levels. The genes Pomtr23C and Pomtr25A exhibited high transcriptional levels, while Pomtr23D/E/F/G/H and Pomtr25B were transcribed constantly at low levels. The gene deletion mutants (Δmtr23C/D/E/F/G/H and Δmtr25A/B) were constructed. Various mutants have different patterns in cellulolytic enzyme production. Compared to the WT, the largest increase in filter paper activity (FPA, indicating total cellulase activity) was observed in the Δmtr23G mutant, the only mutant with a cellulolytic halo surrounding the colony. Three mutants (Δmtr23C/D and Δmtr25A) also showed increased cellulolytic enzyme production. The Δmtr23E and Δmtr25B mutants displayed decreased FPA activity, while the Δmtr23F and Δmtr23H mutants displayed similar patterns of cellulolytic enzyme production compared with the WT. The assay of transcriptional levels of cellobiohydrolase gene Pocbh1 and β-1,4-endoglucanase Poeg1 supported that higher cellulolytic gene transcription resulted in higher production of cellulolytic enzymes, and vice versa. The transcriptional levels of two transcription factors, activator XlnR and repressor CreA, were measured. The high transcription level of the PoxlnR gene in the Δmtr23D mutant should be one reason for the increased transcription of its cellulolytic enzyme gene. Both XlnR and CreA transcriptional levels increased in the Δmtr23G mutant, but the former showed a more significant increase than the latter, indicating that the activation effect predominated. The PoMtr25A is localized in the nucleus. The catalytic subunit SNF2 of the SWI/SNF chromatin-remodeling complex was found as one of the interacting proteins of PoMtr25A via tandem affinity purification coupled with mass spectrometry. PoMtr25A may affect not only the transcription of repressor CreA but also by recruiting SWI/SNF complexes that affect chromatin structure, thereby regulating the transcription of target genes.
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Affiliation(s)
- Zhongjiao Liu
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China; (Z.L.); (K.M.); (X.Z.); (X.S.)
| | - Kexuan Ma
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China; (Z.L.); (K.M.); (X.Z.); (X.S.)
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Xiujun Zhang
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China; (Z.L.); (K.M.); (X.Z.); (X.S.)
- School of Biological Science and Technology, University of Jinan, Jinan 250024, China
| | - Xin Song
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China; (Z.L.); (K.M.); (X.Z.); (X.S.)
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Yuqi Qin
- National Glycoengineering Research Center, Shandong University, Qingdao 266237, China; (Z.L.); (K.M.); (X.Z.); (X.S.)
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
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Lin SY, Oakley CE, Jenkinson CB, Chiang YM, Lee CK, Jones CG, Seidler PM, Nelson HM, Todd RB, Wang CCC, Oakley BR. A heterologous expression platform in Aspergillus nidulans for the elucidation of cryptic secondary metabolism biosynthetic gene clusters: discovery of the Aspergillus fumigatus sartorypyrone biosynthetic pathway. Chem Sci 2023; 14:11022-11032. [PMID: 37860661 PMCID: PMC10583710 DOI: 10.1039/d3sc02226a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 06/26/2023] [Indexed: 10/21/2023] Open
Abstract
Aspergillus fumigatus is a serious human pathogen causing life-threatening Aspergillosis in immunocompromised patients. Secondary metabolites (SMs) play an important role in pathogenesis, but the products of many SM biosynthetic gene clusters (BGCs) remain unknown. In this study, we have developed a heterologous expression platform in Aspergillus nidulans, using a newly created genetic dereplication strain, to express a previously unknown BGC from A. fumigatus and determine its products. The BGC produces sartorypyrones, and we have named it the spy BGC. Analysis of targeted gene deletions by HRESIMS, NMR, and microcrystal electron diffraction (MicroED) enabled us to identify 12 products from the spy BGC. Seven of the compounds have not been isolated previously. We also individually expressed the polyketide synthase (PKS) gene spyA and demonstrated that it produces the polyketide triacetic acid lactone (TAL), a potentially important biorenewable platform chemical. Our data have allowed us to propose a biosynthetic pathway for sartorypyrones and related natural products. This work highlights the potential of using the A. nidulans heterologous expression platform to uncover cryptic BGCs from A. fumigatus and other species, despite the complexity of their secondary metabolomes.
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Affiliation(s)
- Shu-Yi Lin
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California Los Angeles CA 90089 USA
| | - C Elizabeth Oakley
- Department of Molecular Biosciences, University of Kansas 1200 Sunnyside Avenue Lawrence KS 66045 USA
| | - Cory B Jenkinson
- Department of Molecular Biosciences, University of Kansas 1200 Sunnyside Avenue Lawrence KS 66045 USA
| | - Yi-Ming Chiang
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California Los Angeles CA 90089 USA
| | - Ching-Kuo Lee
- School of Pharmacy, College of Pharmacy, Taipei Medical University Taipei 11031 Taiwan
| | - Christopher G Jones
- The Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology Pasadena California 91125 USA
| | - Paul M Seidler
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California Los Angeles CA 90089 USA
| | - Hosea M Nelson
- The Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology Pasadena California 91125 USA
| | - Richard B Todd
- Department of Plant Pathology, Kansas State University Manhattan KS 66506 USA
| | - Clay C C Wang
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California Los Angeles CA 90089 USA
- Department of Chemistry, University of Southern California Los Angeles CA 90089 USA
| | - Berl R Oakley
- Department of Molecular Biosciences, University of Kansas 1200 Sunnyside Avenue Lawrence KS 66045 USA
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Anjum K, Huang X, Zhou L, Zhu T, Che Q, Zhang G, Li D. New cyclic dipeptide discovered from deep-sea derived Aspergillus sp. HDN20-1401. Nat Prod Res 2023:1-6. [PMID: 37384587 DOI: 10.1080/14786419.2023.2227754] [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: 02/03/2023] [Revised: 06/07/2023] [Accepted: 06/15/2023] [Indexed: 07/01/2023]
Abstract
A new alkaloid named aspergilalkaloid A (1) with pyridoindole hydroxymethyl piperazine dione structure along with six known compounds 2-7 were isolated from deep-sea derived fungus Aspergillus sp. HDN20-1401. The structure including absolute configuration was elucidated by extensive NMR analyses, HRESIMS, ECD calculation, and theoretical NMR calculation with DP4+ analysis. All isolated compounds were tested for antimicrobial and anticancer activity. Aspergilalkaloid A (1) showed inhibitive activity against Bacillus cereus with MIC value of 12.5 μM and weak activity against MRCNS.
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Affiliation(s)
- Komal Anjum
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Xiaofei Huang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Luning Zhou
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Tianjiao Zhu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Qian Che
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
| | - Guojian Zhang
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- Marine Biomedical Research Institute of Qingdao, Qingdao, China
| | - Dehai Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
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4
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Ghazawi KF, Fatani SA, Mohamed SGA, Mohamed GA, Ibrahim SRM. Aspergillus nidulans—Natural Metabolites Powerhouse: Structures, Biosynthesis, Bioactivities, and Biotechnological Potential. FERMENTATION-BASEL 2023. [DOI: 10.3390/fermentation9040325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Nowadays, finding out new natural scaffolds of microbial origin increases at a higher rate than in the past decades and represents an auspicious route for reinvigorating the pool of compounds entering pharmaceutical industries. Fungi serve as a depository of fascinating, structurally unique metabolites with considerable therapeutic significance. Aspergillus genus represents one of the most prolific genera of filamentous fungi. Aspergillus nidulans Winter G. is a well-known and plentiful source of bioactive metabolites with abundant structural diversity, including terpenoids, benzophenones, sterols, alkaloids, xanthones, and polyketides, many of which display various bioactivities, such as cytotoxicity, antioxidant, anti-inflammatory, antiviral, and antimicrobial activities. The current work is targeted to survey the reported literature on A. nidulans, particularly its metabolites, biosynthesis, and bioactivities, in addition to recent reports on its biotechnological potential. From 1953 till November 2022, relying on the stated data, 206 metabolites were listed, with more than 100 references.
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5
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Jenkinson CB, Podgorny AR, Zhong C, Oakley BR. Computer-aided, resistance gene-guided genome mining for proteasome and HMG-CoA reductase inhibitors. J Ind Microbiol Biotechnol 2023; 50:kuad045. [PMID: 38061800 PMCID: PMC10734572 DOI: 10.1093/jimb/kuad045] [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: 06/09/2023] [Accepted: 12/06/2023] [Indexed: 12/22/2023]
Abstract
Secondary metabolites (SMs) are biologically active small molecules, many of which are medically valuable. Fungal genomes contain vast numbers of SM biosynthetic gene clusters (BGCs) with unknown products, suggesting that huge numbers of valuable SMs remain to be discovered. It is challenging, however, to identify SM BGCs, among the millions present in fungi, that produce useful compounds. One solution is resistance gene-guided genome mining, which takes advantage of the fact that some BGCs contain a gene encoding a resistant version of the protein targeted by the compound produced by the BGC. The bioinformatic signature of such BGCs is that they contain an allele of an essential gene with no SM biosynthetic function, and there is a second allele elsewhere in the genome. We have developed a computer-assisted approach to resistance gene-guided genome mining that allows users to query large databases for BGCs that putatively make compounds that have targets of therapeutic interest. Working with the MycoCosm genome database, we have applied this approach to look for SM BGCs that target the proteasome β6 subunit, the target of the proteasome inhibitor fellutamide B, or HMG-CoA reductase, the target of cholesterol reducing therapeutics such as lovastatin. Our approach proved effective, finding known fellutamide and lovastatin BGCs as well as fellutamide- and lovastatin-related BGCs with variations in the SM genes that suggest they may produce structural variants of fellutamides and lovastatin. Gratifyingly, we also found BGCs that are not closely related to lovastatin BGCs but putatively produce novel HMG-CoA reductase inhibitors. ONE-SENTENCE SUMMARY A new computer-assisted approach to resistance gene-directed genome mining is reported along with its use to identify fungal biosynthetic gene clusters that putatively produce proteasome and HMG-CoA reductase inhibitors.
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Affiliation(s)
- Cory B Jenkinson
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045,USA
| | - Adam R Podgorny
- Department of Electrical Engineering and Computer Science, University of Kansas, Lawrence, KS 66045,USA
| | - Cuncong Zhong
- Department of Electrical Engineering and Computer Science, University of Kansas, Lawrence, KS 66045,USA
| | - Berl R Oakley
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66045,USA
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6
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Chiang CY, Ohashi M, Tang Y. Deciphering chemical logic of fungal natural product biosynthesis through heterologous expression and genome mining. Nat Prod Rep 2023; 40:89-127. [PMID: 36125308 PMCID: PMC9906657 DOI: 10.1039/d2np00050d] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Covering: 2010 to 2022Heterologous expression of natural product biosynthetic gene clusters (BGCs) has become a widely used tool for genome mining of cryptic pathways, bottom-up investigation of biosynthetic enzymes, and engineered biosynthesis of new natural product variants. In the field of fungal natural products, heterologous expression of a complete pathway was first demonstrated in the biosynthesis of tenellin in Aspergillus oryzae in 2010. Since then, advances in genome sequencing, DNA synthesis, synthetic biology, etc. have led to mining, assignment, and characterization of many fungal BGCs using various heterologous hosts. In this review, we will highlight key examples in the last decade in integrating heterologous expression into genome mining and biosynthetic investigations. The review will cover the choice of heterologous hosts, prioritization of BGCs for structural novelty, and how shunt products from heterologous expression can reveal important insights into the chemical logic of biosynthesis. The review is not meant to be exhaustive but is rather a collection of examples from researchers in the field, including ours, that demonstrates the usefulness and pitfalls of heterologous biosynthesis in fungal natural product discovery.
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Affiliation(s)
- Chen-Yu Chiang
- Dept. of Chemical and Biomolecular Engineering, 5531 Boelter Hall, 420 Westwood Plaza, Los Angeles, CA 90095, USA.
| | - Masao Ohashi
- Dept. of Chemical and Biomolecular Engineering, 5531 Boelter Hall, 420 Westwood Plaza, Los Angeles, CA 90095, USA.
| | - Yi Tang
- Dept. of Chemical and Biomolecular Engineering, 5531 Boelter Hall, 420 Westwood Plaza, Los Angeles, CA 90095, USA.
- Dept. of Chemistry and Biochemistry, 5531 Boelter Hall, 420 Westwood Plaza, Los Angeles, CA 90095, USA
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7
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Complementary Strategies to Unlock Biosynthesis Gene Clusters Encoding Secondary Metabolites in the Filamentous Fungus Podospora anserina. J Fungi (Basel) 2022; 9:jof9010009. [PMID: 36675830 PMCID: PMC9864250 DOI: 10.3390/jof9010009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/09/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022] Open
Abstract
The coprophilous ascomycete Podospora anserina is known to have a high potential to synthesize a wide array of secondary metabolites (SMs). However, to date, the characterization of SMs in this species, as in other filamentous fungal species, is far less than expected by the functional prediction through genome mining, likely due to the inactivity of most SMs biosynthesis gene clusters (BGCs) under standard conditions. In this work, our main objective was to compare the global strategies usually used to deregulate SM gene clusters in P. anserina, including the variation of culture conditions and the modification of the chromatin state either by genetic manipulation or by chemical treatment, and to show the complementarity of the approaches between them. In this way, we showed that the metabolomics-driven comparative analysis unveils the unexpected diversity of metabolic changes in P. anserina and that the integrated strategies have a mutual complementary effect on the expression of the fungal metabolome. Then, our results demonstrate that metabolite production is significantly influenced by varied cultivation states and epigenetic modifications. We believe that the strategy described in this study will facilitate the discovery of fungal metabolites of interest and will improve the ability to prioritize the production of specific fungal SMs with an optimized treatment.
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8
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Itaconic acid production is regulated by LaeA in Aspergillus pseudoterreus. Metab Eng Commun 2022; 15:e00203. [PMID: 36065328 PMCID: PMC9440423 DOI: 10.1016/j.mec.2022.e00203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 07/08/2022] [Accepted: 08/15/2022] [Indexed: 11/22/2022] Open
Abstract
The global regulator LaeA controls secondary metabolism in diverse Aspergillus species. Here we explored its role in regulation of itaconic acid production in Aspergillus pseudoterreus. To understand its role in regulating metabolism, we deleted and overexpressed laeA, and assessed the transcriptome, proteome, and secreted metabolome prior to and during initiation of phosphate limitation induced itaconic acid production. We found that secondary metabolite clusters, including the itaconic acid biosynthetic gene cluster, are regulated by laeA and that laeA is required for high yield production of itaconic acid. Overexpression of LaeA improves itaconic acid yield at the expense of biomass by increasing the expression of key biosynthetic pathway enzymes and attenuating the expression of genes involved in phosphate acquisition and scavenging. Increased yield was observed in optimized conditions as well as conditions containing excess nutrients that may be present in inexpensive sugar containing feedstocks such as excess phosphate or complex nutrient sources. This suggests that global regulators of metabolism may be useful targets for engineering metabolic flux that is robust to environmental heterogeneity. The Itaconic acid biosynthetic gene cluster is regulated by laeA. LaeA is required for production of itaconic acid. Overexpression of laeA attenuates genes involved in phosphate acquisition. Global regulator engineering increases robustness of itaconic acid production.
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9
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Wang Y, Chen Y, Zhang J, Zhang C. Overexpression of llm1 Affects the Synthesis of Secondary Metabolites of Aspergillus cristatus. Microorganisms 2022; 10:microorganisms10091707. [PMID: 36144309 PMCID: PMC9502445 DOI: 10.3390/microorganisms10091707] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 08/19/2022] [Accepted: 08/21/2022] [Indexed: 12/04/2022] Open
Abstract
Putative methyltransferases are thought to be involved in the regulation of secondary metabolites in filamentous fungi. Here, we report the effects of overexpression of a predicted LaeA-like methyltransferase gene llm1 on the synthesis of secondary metabolites in Aspergillus cristatus. Our results revealed that overexpression of the gene llm1 in A. cristatus significantly hindered the production of conidia and enhanced sexual development, and reduced oxidative tolerance to hydrogen peroxide. Compared with the wild-type, the metabolic profile of the overexpression transformant was distinct, and the contents of multiple secondary metabolites were markedly increased, mainly including terpenoids and flavonoids, such as (S)-olEuropeic acid, gibberellin A62, gibberellin A95, ovalitenone, PD 98059, and 1-isomangostin. A total of 600 significantly differentially expressed genes (DEGs) were identified utilizing transcriptome sequencing, and the DEGs were predominantly enriched in transmembrane transport and secondary metabolism-related biological processes. In summary, the strategy of overexpressing global secondary metabolite regulators successfully activated the expression of secondary metabolite gene clusters, and the numerous secondary metabolites were greatly strengthened in A. cristatus. This study provides new insights into the in-depth exploitation and utilization of novel secondary metabolites of A. cristatus.
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10
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RimO (SrrB) is required for carbon starvation signaling and production of secondary metabolites in Aspergillus nidulans. Fungal Genet Biol 2022; 162:103726. [PMID: 35843417 DOI: 10.1016/j.fgb.2022.103726] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 06/17/2022] [Accepted: 07/09/2022] [Indexed: 11/20/2022]
Abstract
Depending on the prevailing environmental, developmental and nutritional conditions, fungi activate biosynthetic gene clusters (BGCs) to produce condition-specific secondary metabolites (SMs). For activation, global chromatin-based de-repression must be integrated with pathway-specific induction signals. Here we describe a new global regulator needed to activate starvation-induced SMs. In our transcriptome dataset, we found locus AN7572 strongly transcribed solely under conditions of starvation-induced SM production. The predicted AN7572 protein is most similar to the stress and nutritional regulator Rim15 of Saccharomyces cerevisiae, and to STK-12 of Neurospora crassa. Based on this similarity and on stress and nutritional response phenotypes of A. nidulans knock-out and overexpression strains, AN7572 is designated rimO. In relation to SM production, we found that RimO is required for the activation of starvation-induced BGCs, including the sterigmatocystin (ST) gene cluster. Here, RimO regulates the pathway-specific transcription factor AflR both at the transcriptional and post-translational level. At the transcriptional level, RimO mediates aflR induction following carbon starvation and at the post-translational level, RimO is required for nuclear accumulation of the AflR protein. Genome-wide transcriptional profiling showed that cells lacking rimO fail to adapt to carbon starvation that, in the wild type, leads to down-regulation of genes involved in basic metabolism, membrane biogenesis and growth. Consistently, strains overexpressing rimO are more resistant to oxidative and osmotic stress, largely insensitive to glucose repression and strongly overproduce several SMs. Our data indicate that RimO is a positive regulator within the SM and stress response network, but this requires nutrient depletion that triggers both, rimO gene transcription and activation of the RimO protein.
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11
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Gubiani JR, Bernardi DI, De Paula CCP, Seleghim MHR, Ferreira AG, Batista ANL, Batista JM, Oliveira LFP, Lira SP, Burdette JE, Berlinck RGS. Absolute configuration of cytotoxic anthraquinones from a Brazilian cave soil-derived fungus, Aspergillus sp. SDC28. Arch Pharm (Weinheim) 2022; 355:e2100441. [PMID: 35099085 PMCID: PMC8983557 DOI: 10.1002/ardp.202100441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 01/03/2022] [Accepted: 01/07/2022] [Indexed: 01/26/2023]
Abstract
Microbial strains isolated from extreme and understudied environments, such as caves, are still poorly investigated for the production of bioactive secondary metabolites. Investigation of the ethyl acetate extract from the growth medium produced by the soil-derived fungus Aspergillus sp. SDC28, isolated from a Brazilian cave, yielded two anthraquinones: versicolorin C (1) and versiconol (2). The complete assignment of nuclear magnetic resonance and mass spectroscopic data of 1 and 2 was performed for the first time. Moreover, the yet unreported absolute configuration of both compounds was unambiguously established by analysis of experimental and theoretical electronic circular dichroism data. Vibrational circular dichroism was also applied to confirm the absolute stereochemistry of 2. Compounds 1 and 2 showed cytotoxic activity against human ovarian cancer cells (OVCAR3).
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Affiliation(s)
- Juliana R Gubiani
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, Brazil
| | - Darlon I Bernardi
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, Brazil
| | - Caio C P De Paula
- Departamento de Ecologia e Biologia Evolutiva, Universidade Federal de São Carlos, São Carlos, Brazil.,Biology Centre CAS, Institute of Hydrobiology, České Budějovice, Czech Republic
| | - Mirna H R Seleghim
- Departamento de Ecologia e Biologia Evolutiva, Universidade Federal de São Carlos, São Carlos, Brazil
| | - Antonio G Ferreira
- Departamento de Química, Universidade Federal de São Carlos, São Carlos, Brazil
| | | | - João M Batista
- Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo, São José dos Campos, Brazil
| | - Lucianne F P Oliveira
- Departamento de Ciências Exatas, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, Brazil
| | - Simone P Lira
- Departamento de Ciências Exatas, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, Brazil
| | - Joanna E Burdette
- Pharmaceutical Sciences, College of Pharmacy, University of Illinois, Ashland, Oregon, USA
| | - Roberto G S Berlinck
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, Brazil
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12
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Functional characterization of the GATA-type transcription factor PaNsdD in the filamentous fungus Podospora anserina and its interplay with the sterigmatocystin pathway. Appl Environ Microbiol 2022; 88:e0237821. [PMID: 35080910 PMCID: PMC8939327 DOI: 10.1128/aem.02378-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The model ascomycete Podospora anserina, distinguished by its strict sexual development, is a prolific but yet unexploited reservoir of natural products. The GATA-type transcription factor NsdD has been characterized by the role in balancing asexual and sexual reproduction and governing secondary metabolism in filamentous fungi. In the present study, we functionally investigated the NsdD ortholog PaNsdD in P. anserina. Compared to the wild-type strain, vegetative growth, ageing processes, sexual reproduction, stress tolerance, and interspecific confrontations in the mutant were drastically impaired, owing to the loss of function of PaNsdD. In addition, the production of 3-acetyl-4-methylpyrrole, a new metabolite identified in P. anserina in this study, was significantly inhibited in the ΔPaNsdD mutant. We also demonstrated the interplay of PaNsdD with the sterigmatocystin biosynthetic gene pathway, especially as the deletion of PaNsdD triggered the enhanced red-pink pigment biosynthesis that occurs only in the presence of the core polyketide synthase-encoding gene PaStcA of the sterigmatocystin pathway. Taken together, these results contribute to a better understanding of the global regulation mediated by PaNsdD in P. anserina, especially with regard to its unexpected involvement in the fungal ageing process and its interplay with the sterigmatocystin pathway. IMPORTANCE Fungal transcription factors play an essential role in coordinating multiple physiological processes. However, little is known about the functional characterization of transcription factors in the filamentous fungus Podospora anserina. In this study, a GATA-type regulator PaNsdD was investigated in P. anserina. The results showed that PaNsdD was a key factor that can control the fungal ageing process, vegetative growth, pigmentation, stress response, and interspecific confrontations and positively regulate the production of 3-acetyl-4-methylpyrrole. Meanwhile, a molecular interaction was implied between PaNsdD and the sterigmatocystin pathway. Overall, loss of function of PaNsdD seems to be highly disadvantageous for P. anserina, which relies on pure sexual reproduction in a limited life span. Therefore, PaNsdD is clearly indispensable for the survival and propagation of P. anserina in its complex ecological niches.
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13
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Yao Y, Wang W, Shi W, Yan R, Zhang J, Wei G, Liu L, Che Y, An C, Gao SS. Overproduction of medicinal ergot alkaloids based on a fungal platform. Metab Eng 2021; 69:198-208. [PMID: 34902590 DOI: 10.1016/j.ymben.2021.12.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 11/17/2021] [Accepted: 12/08/2021] [Indexed: 12/21/2022]
Abstract
Privileged ergot alkaloids (EAs) produced by the fungal genus Claviceps are used to treat a wide range of diseases. However, their use and research have been hampered by the challenging genetic engineering of Claviceps. Here we systematically refactored and rationally engineered the EA biosynthetic pathway in heterologous host Aspergillus nidulans by using a Fungal-Yeast-Shuttle-Vector protocol. The obtained strains allowed the production of diverse EAs and related intermediates, including prechanoclavine (PCC, 333.8 mg/L), chanoclavine (CC, 241.0 mg/L), agroclavine (AC, 78.7 mg/L), and festuclavine (FC, 99.2 mg/L), etc. This fungal platform also enabled the access to the methyl-oxidized EAs (MOEAs), including elymoclavine (EC), lysergic acid (LA), dihydroelysergol (DHLG), and dihydrolysergic acid (DHLA), by overexpressing a P450 enzyme CloA. Furthermore, by optimizing the P450 electron transfer (ET) pathway and using multi-copy of cloA, the titers of EC and DHLG have been improved by 17.3- and 9.4-fold, respectively. Beyond our demonstration of A. nidulans as a robust platform for EA overproduction, our study offers a proof of concept for engineering the eukaryotic P450s-contained biosynthetic pathways in a filamentous fungal host.
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Affiliation(s)
- Yongpeng Yao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China
| | - Wei Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Wenyu Shi
- Microbial Resource and Big Data Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China
| | - Rui Yan
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China
| | - Jun Zhang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China
| | - Guangzheng Wei
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Ling Liu
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China
| | - Yongsheng Che
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, PR China
| | - Chunyan An
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China.
| | - Shu-Shan Gao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, PR China.
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Meng X, Fang Y, Ding M, Zhang Y, Jia K, Li Z, Collemare J, Liu W. Developing fungal heterologous expression platforms to explore and improve the production of natural products from fungal biodiversity. Biotechnol Adv 2021; 54:107866. [PMID: 34780934 DOI: 10.1016/j.biotechadv.2021.107866] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 10/04/2021] [Accepted: 11/05/2021] [Indexed: 12/14/2022]
Abstract
Natural products from fungi represent an important source of biologically active metabolites notably for therapeutic agent development. Genome sequencing revealed that the number of biosynthetic gene clusters (BGCs) in fungi is much larger than expected. Unfortunately, most of them are silent or barely expressed under laboratory culture conditions. Moreover, many fungi in nature are uncultivable or cannot be genetically manipulated, restricting the extraction and identification of bioactive metabolites from these species. Rapid exploration of the tremendous number of cryptic fungal BGCs necessitates the development of heterologous expression platforms, which will facilitate the efficient production of natural products in fungal cell factories. Host selection, BGC assembly methods, promoters used for heterologous gene expression, metabolic engineering strategies and compartmentalization of biosynthetic pathways are key aspects for consideration to develop such a microbial platform. In the present review, we summarize current progress on the above challenges to promote research effort in the relevant fields.
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Affiliation(s)
- Xiangfeng Meng
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, PR China
| | - Yu Fang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, PR China
| | - Mingyang Ding
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, PR China
| | - Yanyu Zhang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, PR China
| | - Kaili Jia
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, PR China
| | - Zhongye Li
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, PR China
| | - Jérôme Collemare
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands.
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, PR China.
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15
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Cheng JT, Yu JH, Sun CF, Cao F, Ying YM, Zhan ZJ, Li WJ, Chen XA, Zhao QW, Li YQ, Gan LS, Mao XM. A Cell Factory of a Fungicolous Fungus Calcarisporium arbuscula for Efficient Production of Natural Products. ACS Synth Biol 2021; 10:698-706. [PMID: 33720696 DOI: 10.1021/acssynbio.0c00371] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Fungal natural products are rich sources of clinical drugs. Particularly, the fungicolous fungi have a large number of biosynthetic gene clusters (BGCs) to produce numerous bioactive natural products, but most BGCs are silent in the laboratory. We have shown that a fungicolous fungus Calcarisporium arbuscula NRRL 3705 predominantly produces the highly reduced polyketide-type mycotoxins aurovertins. Here after evaluation of the aurovertin-null mutant ΔaurA as an efficient host, we further screened two strong promoters aurBp and A07068p based on RNA-Seq, and successfully activated an endogenous gene cluster from C. arbuscula as well as three additional exogenous BGCs from other fungi to produce polyketide-type natural products. Thus, we showed an efficient expression system from the fungicolous fungus C. arbuscula, which will be highly beneficial and complementary to the conventional Aspergillus and Penicillium fungal cell factories, and provides a useful toolkit for genome-wide mining of bioactive natural products from fungicolous fungi.
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Affiliation(s)
- Jin-Tao Cheng
- Institute of Pharmaceutical Biotechnology & Research Center for Clinical Pharmacy, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310058, P. R. China
- Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering, Hangzhou, 310058, P. R. China
| | - Jia-Hui Yu
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, P. R. China
| | - Chen-Fan Sun
- Institute of Pharmaceutical Biotechnology & Research Center for Clinical Pharmacy, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310058, P. R. China
- Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering, Hangzhou, 310058, P. R. China
| | - Fei Cao
- Institute of Pharmaceutical Biotechnology & Research Center for Clinical Pharmacy, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310058, P. R. China
- Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering, Hangzhou, 310058, P. R. China
| | - You-Min Ying
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, 310014, P. R. China
| | - Zha-Jun Zhan
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, 310014, P. R. China
| | - Wen-Ju Li
- Jinan Samuel Pharmaceutical Co., Ltd of Shandong Province, Jinan, 250100, P. R. China
| | - Xin-Ai Chen
- Institute of Pharmaceutical Biotechnology & Research Center for Clinical Pharmacy, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310058, P. R. China
- Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering, Hangzhou, 310058, P. R. China
| | - Qing-Wei Zhao
- Institute of Pharmaceutical Biotechnology & Research Center for Clinical Pharmacy, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Yong-Quan Li
- Institute of Pharmaceutical Biotechnology & Research Center for Clinical Pharmacy, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310058, P. R. China
- Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering, Hangzhou, 310058, P. R. China
| | - Li-She Gan
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, P. R. China
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, 310058, P. R. China
| | - Xu-Ming Mao
- Institute of Pharmaceutical Biotechnology & Research Center for Clinical Pharmacy, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310058, P. R. China
- Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering, Hangzhou, 310058, P. R. China
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16
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Pardo-Medina J, Gutiérrez G, Limón MC, Avalos J. Impact of the White Collar Photoreceptor WcoA on the Fusarium fujikuroi Transcriptome. Front Microbiol 2021; 11:619474. [PMID: 33574802 PMCID: PMC7871910 DOI: 10.3389/fmicb.2020.619474] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 12/18/2020] [Indexed: 01/25/2023] Open
Abstract
The proteins of the White Collar 1 family (WC) constitute a major class of flavin photoreceptors, widely distributed in fungi, that work in cooperation with a WC 2 protein forming a regulatory complex. The WC complex was investigated in great detail in Neurospora crassa, a model fungus in photobiology studies, where it controls all its major photoresponses. The fungus Fusarium fujikuroi, a model system in the production of secondary metabolites, contains a single WC-1 gene called wcoA. The best-known light response in this fungus is the photoinduction of the synthesis of carotenoids, terpenoid pigments with antioxidant properties. Loss of WcoA in F. fujikuroi results in a drastic reduction in the mRNA levels of the carotenoid genes, and a diversity of morphological and metabolic changes, including alterations in the synthesis of several secondary metabolites, suggesting a complex regulatory role. To investigate the function of WcoA, the transcriptome of F. fujikuroi was analyzed in the dark and after 15-, 60- or 240-min illumination in a wild strain and in a formerly investigated wcoA insertional mutant. Using a threshold of four-fold change in transcript levels, 298 genes were activated and 160 were repressed in the wild strain under at least one of the light exposures. Different response patterns were observed among them, with genes exhibiting either fast, intermediate, and slow photoinduction, or intermediate or slow repression. All the fast and intermediate photoresponses, and most of the slow ones, were lost in the wcoA mutant. However, the wcoA mutation altered the expression of a much larger number of genes irrespective of illumination, reaching at least 16% of the annotated genes in this fungus. Such genes include many related to secondary metabolism, as well as others related to photobiology and other cellular functions, including the production of hydrophobins. As judged by the massive transcriptomic changes exhibited by the wcoA mutant in the dark, the results point to WcoA as a master regulatory protein in F. fujikuroi, in addition to a central function as the photoreceptor responsible for most of the transcriptional responses to light in this fungus.
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Affiliation(s)
- Javier Pardo-Medina
- Department of Genetics, Faculty of Biology, University of Seville, Seville, Spain
| | - Gabriel Gutiérrez
- Department of Genetics, Faculty of Biology, University of Seville, Seville, Spain
| | - M Carmen Limón
- Department of Genetics, Faculty of Biology, University of Seville, Seville, Spain
| | - Javier Avalos
- Department of Genetics, Faculty of Biology, University of Seville, Seville, Spain
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17
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Romero-Aguilar L, Cárdenas-Monroy C, Garrido-Bazán V, Aguirre J, Guerra-Sánchez G, Pardo JP. On the use of n-octyl gallate and salicylhydroxamic acid to study the alternative oxidase role. Arch Biochem Biophys 2020; 694:108603. [PMID: 32986977 DOI: 10.1016/j.abb.2020.108603] [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: 07/19/2020] [Revised: 08/28/2020] [Accepted: 09/24/2020] [Indexed: 10/23/2022]
Abstract
The alternative oxidase (AOX) catalyzes the transfer of electrons from ubiquinol to oxygen without the translocation of protons across the inner mitochondrial membrane. This enzyme has been proposed to participate in the regulation of cell growth, sporulation, yeast-mycelium transition, resistance to reactive oxygen species, infection, and production of secondary metabolites. Two approaches have been used to evaluate AOX function: incubation of cells for long periods of time with AOX inhibitors or deletion of AOX gene. However, AOX inhibitors might have different targets. To test non-specific effects of n-octyl gallate (nOg) and salicylhydroxamic acid (SHAM) on fungal physiology we measured the growth and respiratory capacity of two fungal strains lacking (Ustilago maydis-Δaox and Saccharomyces cerevisiae) and three species containing the AOX gene (U. maydis WT, Debaryomyces hansenii, and Aspergillus nidulans). For U. maydis, a strong inhibition of growth and respiratory capacity by SHAM was observed, regardless of the presence of AOX. Similarly, A. nidulans mycelial growth was inhibited by low concentrations of nOg independently of AOX expression. In contrast, these inhibitors had no effect or had a minor effect on S. cerevisiae and D. hansenii growth. These results show that nOg and SHAM have AOX independent effects which vary in different microorganisms, indicating that studies based on long-term incubation of cells with these inhibitors should be considered as inconclusive.
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Affiliation(s)
- Lucero Romero-Aguilar
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Copilco, Cd. Universitaria, Coyoacán, 04510, Ciudad de México, Mexico
| | - Christian Cárdenas-Monroy
- Ciencia Forense, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Copilco, Cd. Universitaria, Coyoacán, 04510, Ciudad de México, Mexico
| | - Verónica Garrido-Bazán
- Departamento de Biología Celular y del Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Copilco, Cd. Universitaria, Coyoacán, 04510, Ciudad de México, Mexico
| | - Jesus Aguirre
- Departamento de Biología Celular y del Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Copilco, Cd. Universitaria, Coyoacán, 04510, Ciudad de México, Mexico
| | - Guadalupe Guerra-Sánchez
- Departamento de Microbiología, Laboratorio de Bioquímica y Biotecnología de Hongos, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Carpio y Plan de Ayala S/N., Miguel Hidalgo, 11350, Ciudad de México, Mexico
| | - Juan Pablo Pardo
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Copilco, Cd. Universitaria, Coyoacán, 04510, Ciudad de México, Mexico.
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18
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Schüller A, Wolansky L, Berger H, Studt L, Gacek-Matthews A, Sulyok M, Strauss J. A novel fungal gene regulation system based on inducible VPR-dCas9 and nucleosome map-guided sgRNA positioning. Appl Microbiol Biotechnol 2020; 104:9801-9822. [PMID: 33006690 PMCID: PMC7595996 DOI: 10.1007/s00253-020-10900-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 08/31/2020] [Accepted: 09/08/2020] [Indexed: 12/16/2022]
Abstract
Programmable transcriptional regulation is a powerful tool to study gene functions. Current methods to selectively regulate target genes are mainly based on promoter exchange or on overexpressing transcriptional activators. To expand the discovery toolbox, we designed a dCas9-based RNA-guided synthetic transcription activation system for Aspergillus nidulans that uses enzymatically disabled "dead" Cas9 fused to three consecutive activation domains (VPR-dCas9). The dCas9-encoding gene is under the control of an estrogen-responsive promoter to allow induction timing and to avoid possible negative effects by strong constitutive expression of the highly active VPR domains. Especially in silent genomic regions, facultative heterochromatin and strictly positioned nucleosomes can constitute a relevant obstacle to the transcriptional machinery. To avoid this negative impact and to facilitate optimal positioning of RNA-guided VPR-dCas9 to targeted promoters, we have created a genome-wide nucleosome map from actively growing cells and stationary cultures to identify the cognate nucleosome-free regions (NFRs). Based on these maps, different single-guide RNAs (sgRNAs) were designed and tested for their targeting and activation potential. Our results demonstrate that the system can be used to regulate several genes in parallel and, depending on the VPR-dCas9 positioning, expression can be pushed to very high levels. We have used the system to turn on individual genes within two different biosynthetic gene clusters (BGCs) which are silent under normal growth conditions. This method also opens opportunities to stepwise activate individual genes in a cluster to decipher the correlated biosynthetic pathway. Graphical abstract KEYPOINTS: • An inducible RNA-guided transcriptional regulator based on VPR-dCas9 was established in Aspergillus nidulans. • Genome-wide nucleosome positioning maps were created that facilitate sgRNA positioning. • The system was successfully applied to activate genes within two silent biosynthetic gene clusters.
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Affiliation(s)
- Andreas Schüller
- Fungal Genetics Lab, Institute of Microbial Genetics, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life Sciences Vienna, BOKU-Campus Tulln, Konrad Lorenz Strasse 24, A-3430, Tulln an der Donau, Austria
| | - Lisa Wolansky
- Institute Krems Bioanalytics , IMC FH Krems University of Applied Sciences , Krems, Austria
| | - Harald Berger
- Fungal Genetics Lab, Institute of Microbial Genetics, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life Sciences Vienna, BOKU-Campus Tulln, Konrad Lorenz Strasse 24, A-3430, Tulln an der Donau, Austria
| | - Lena Studt
- Fungal Genetics Lab, Institute of Microbial Genetics, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life Sciences Vienna, BOKU-Campus Tulln, Konrad Lorenz Strasse 24, A-3430, Tulln an der Donau, Austria
| | - Agnieszka Gacek-Matthews
- Fungal Genetics Lab, Institute of Microbial Genetics, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life Sciences Vienna, BOKU-Campus Tulln, Konrad Lorenz Strasse 24, A-3430, Tulln an der Donau, Austria
- Institute of Microbiology, Functional Microbiology Division, University of Veterinary Sciences Vienna, Wien, Austria
| | - Michael Sulyok
- Institute of Bioanalytics and Agrometabolomics, Department of Agrobiotechnology, BOKU-University of Natural Resources and Life Sciences Vienna, BOKU-Campus Tulln, Konrad-Lorenz-Straße 20, A-3430 Tulln an der Donau, Austria
| | - Joseph Strauss
- Fungal Genetics Lab, Institute of Microbial Genetics, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life Sciences Vienna, BOKU-Campus Tulln, Konrad Lorenz Strasse 24, A-3430, Tulln an der Donau, Austria.
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19
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Caesar LK, Kelleher NL, Keller NP. In the fungus where it happens: History and future propelling Aspergillus nidulans as the archetype of natural products research. Fungal Genet Biol 2020; 144:103477. [PMID: 33035657 DOI: 10.1016/j.fgb.2020.103477] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/21/2020] [Accepted: 09/30/2020] [Indexed: 02/08/2023]
Abstract
In 1990 the first fungal secondary metabolite biosynthetic gene was cloned in Aspergillus nidulans. Thirty years later, >30 biosynthetic gene clusters (BGCs) have been linked to specific natural products in this one fungal species. While impressive, over half of the BGCs in A. nidulans remain uncharacterized and their compounds structurally and functionally unknown. Here, we provide a comprehensive review of past advances that have enabled A. nidulans to rise to its current status as a natural product powerhouse focusing on the discovery and annotation of secondary metabolite clusters. From genome sequencing, heterologous expression, and metabolomics to CRISPR and epigenetic manipulations, we present a guided tour through the evolution of technologies developed and utilized in the last 30 years. These insights provide perspective to future efforts to fully unlock the biosynthetic potential of A. nidulans and, by extension, the potential of other filamentous fungi.
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Affiliation(s)
- Lindsay K Caesar
- Department of Chemistry, Northwestern University, Evanston, IL, United States
| | - Neil L Kelleher
- Department of Chemistry, Northwestern University, Evanston, IL, United States; Department of Molecular Biosciences, Northwestern University, Evanston, IL, United States; Proteomics Center of Excellence, Northwestern University, Evanston, IL, United States
| | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin- Madison, Madison, WI, United States; Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, United States.
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20
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Zhang X, Li M, Zhu Y, Yang L, Li Y, Qu J, Wang L, Zhao J, Qu Y, Qin Y. Penicillium oxalicum putative methyltransferase Mtr23B has similarities and differences with LaeA in regulating conidium development and glycoside hydrolase gene expression. Fungal Genet Biol 2020; 143:103445. [PMID: 32822857 DOI: 10.1016/j.fgb.2020.103445] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 08/07/2020] [Accepted: 08/12/2020] [Indexed: 11/18/2022]
Abstract
Putative methyltranferase LaeA and LaeA-like proteins, which are conserved in many filamentous fungi, regulate the sporogenesis and biosynthesis of secondary metabolites. In this study, we reported the biological function of a LaeA-like methyltransferase, Penicillium oxalicum Mtr23B, which contains a methyltransf_23 domain and an S-adenosylmethionine binding domain, in controlling spore pigment formation and in the expression of secondary metabolic gene cluster and glycoside hydrolase genes. Additionally, we compared Mtr23B and LaeA, and determined their similarities and differences in terms of their roles in regulating the above biological processes. mtr23B had the highest transcriptional level among the 12 members of the methyltransf_23 family in P. oxalicum. The colony color of Δmtr23B (deletion of mtr23B) was lighter than that of ΔlaeA, although Δmtr23B produced ~ 19.2-fold more conidia than ΔlaeA. The transcriptional levels of abrA, abrB/yA, albA/wA, arpA, arpB, and aygA, which are involved in the dihydroxynaphtalene-melanin pathway, decreased in Δmtr23B. However, Mtr23B had a little effect on brush-like structures and conidium formation, and had a different function from LaeA. Mtr23B extensively regulated glycoside hydrolase gene expression. The absence of Mtr23B remarkably repressed prominent cellulase- and amylase-encoding genes in the whole culture period, while the effect of LaeA mainly occurred in the later phases of prolonged batch cultures. Similar to LaeA, Mtr23B was involved in the expression of 10 physically linked regions containing secondary metabolic gene clusters; the highest regulatory activities of Mtr23B and LaeA were observed in BrlA-dependent cascades. Although LaeA interacted with VeA, Mtr23B did not interact with VeA directly. We assumed that Mtr23B regulates cellulase and amylase gene transcription by interacting with the CCAAT-binding transcription factor HAP5 and chromatin remodeling complex.
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Affiliation(s)
- Xiujun Zhang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Mengxue Li
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China
| | - Yingying Zhu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China
| | - Ling Yang
- Vocational Education College, Dezhou University, Dezhou 253023, China
| | - Yanan Li
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China
| | - Jingyao Qu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Lushan Wang
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Yuqi Qin
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
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