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Díaz-Tapia KM, Zavala-Páramo MG, Villa-Rivera MG, Morelos-Martínez MI, López-Romero E, Simpson J, Bolaños-Rebolledo J, Cano-Camacho H. Differential Carbon Catabolite Repression and Hemicellulolytic Ability among Pathotypes of Colletotrichum lindemuthianum against Natural Plant Substrates. J Fungi (Basel) 2024; 10:406. [PMID: 38921392 PMCID: PMC11204554 DOI: 10.3390/jof10060406] [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: 05/08/2024] [Revised: 05/31/2024] [Accepted: 06/03/2024] [Indexed: 06/27/2024] Open
Abstract
Colletotrichum lindemuthianum is a phytopathogenic fungus that causes anthracnose in common beans (Phaseolus vulgaris) and presents a great diversity of pathotypes with different levels of virulence against bean varieties worldwide. The purpose of this study was to establish whether pathotypic diversity is associated with differences in the mycelial growth and secretion of plant-cell-wall-degrading enzymes (PCWDEs). We evaluated growth, hemicellulase and cellulase activity, and PCWDE secretion in four pathotypes of C. lindemuthianum in cultures with glucose, bean hypocotyls and green beans of P. vulgaris, and water hyacinth (Eichhornia crassipes). The results showed differences in the mycelial growth, hemicellulolytic activity, and PCWDE secretion among the pathotypes. Glucose was not the preferred carbon source for the best mycelial growth in all pathotypes, each of which showed a unique PCWDE secretion profile, indicating different levels of carbon catabolite regulation (CCR). The pathotypes showed a high differential hemicellulolytic capacity to degrade host and water hyacinth tissues, suggesting CCR by pentoses and that there are differences in the absorption and metabolism of different monosaccharides and/or disaccharides. We propose that different levels of CCR could optimize growth in different host tissues and could allow for consortium behavior in interactions with bean crops.
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Affiliation(s)
- Karla Morelia Díaz-Tapia
- Centro Multidisciplinario de Estudios en Biotecnología, FMVZ, Universidad Michoacana de San Nicolás de Hidalgo, Km 9.5 Carretera Morelia-Zinapécuaro, Posta Veterinaria, Morelia 58000, Michoacán, Mexico; (K.M.D.-T.); (M.I.M.-M.); (J.B.-R.)
| | - María Guadalupe Zavala-Páramo
- Centro Multidisciplinario de Estudios en Biotecnología, FMVZ, Universidad Michoacana de San Nicolás de Hidalgo, Km 9.5 Carretera Morelia-Zinapécuaro, Posta Veterinaria, Morelia 58000, Michoacán, Mexico; (K.M.D.-T.); (M.I.M.-M.); (J.B.-R.)
| | - Maria Guadalupe Villa-Rivera
- Escuela Nacional de Estudios Superiores, Unidad Morelia, Universidad Autónoma de México, Antigua Carretera a Pátzcuaro No. 8701, Morelia 58190, Michoacán, Mexico;
| | - Ma. Irene Morelos-Martínez
- Centro Multidisciplinario de Estudios en Biotecnología, FMVZ, Universidad Michoacana de San Nicolás de Hidalgo, Km 9.5 Carretera Morelia-Zinapécuaro, Posta Veterinaria, Morelia 58000, Michoacán, Mexico; (K.M.D.-T.); (M.I.M.-M.); (J.B.-R.)
| | - Everardo López-Romero
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta SN, Guanajuato 36030, Guanajuato, Mexico;
| | - June Simpson
- Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Unidad Irapuato, Km 9.6 Libramiento Norte Carretera Irapuato-León, Irapuato 36821, Guanajuato, Mexico;
| | - Jeni Bolaños-Rebolledo
- Centro Multidisciplinario de Estudios en Biotecnología, FMVZ, Universidad Michoacana de San Nicolás de Hidalgo, Km 9.5 Carretera Morelia-Zinapécuaro, Posta Veterinaria, Morelia 58000, Michoacán, Mexico; (K.M.D.-T.); (M.I.M.-M.); (J.B.-R.)
| | - Horacio Cano-Camacho
- Centro Multidisciplinario de Estudios en Biotecnología, FMVZ, Universidad Michoacana de San Nicolás de Hidalgo, Km 9.5 Carretera Morelia-Zinapécuaro, Posta Veterinaria, Morelia 58000, Michoacán, Mexico; (K.M.D.-T.); (M.I.M.-M.); (J.B.-R.)
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Castañeda-Casasola CC, Nieto-Jacobo MF, Soares A, Padilla-Padilla EA, Anducho-Reyes MA, Brown C, Soth S, Esquivel-Naranjo EU, Hampton J, Mendoza-Mendoza A. Unveiling a Microexon Switch: Novel Regulation of the Activities of Sugar Assimilation and Plant-Cell-Wall-Degrading Xylanases and Cellulases by Xlr2 in Trichoderma virens. Int J Mol Sci 2024; 25:5172. [PMID: 38791210 PMCID: PMC11121469 DOI: 10.3390/ijms25105172] [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: 03/20/2024] [Revised: 05/02/2024] [Accepted: 05/06/2024] [Indexed: 05/26/2024] Open
Abstract
Functional microexons have not previously been described in filamentous fungi. Here, we describe a novel mechanism of transcriptional regulation in Trichoderma requiring the inclusion of a microexon from the Xlr2 gene. In low-glucose environments, a long mRNA including the microexon encodes a protein with a GAL4-like DNA-binding domain (Xlr2-α), whereas in high-glucose environments, a short mRNA that is produced encodes a protein lacking this DNA-binding domain (Xlr2-β). Interestingly, the protein isoforms differ in their impact on cellulase and xylanase activity. Deleting the Xlr2 gene reduced both xylanase and cellulase activity and growth on different carbon sources, such as carboxymethylcellulose, xylan, glucose, and arabinose. The overexpression of either Xlr2-α or Xlr2-β in T. virens showed that the short isoform (Xlr2-β) caused higher xylanase activity than the wild types or the long isoform (Xlr2-α). Conversely, cellulase activity did not increase when overexpressing Xlr2-β but was increased with the overexpression of Xlr2-α. This is the first report of a novel transcriptional regulation mechanism of plant-cell-wall-degrading enzyme activity in T. virens. This involves the differential expression of a microexon from a gene encoding a transcriptional regulator.
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Affiliation(s)
- Cynthia Coccet Castañeda-Casasola
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln 7647, New Zealand; (C.C.C.-C.); (A.S.); (E.A.P.-P.); (S.S.); (E.U.E.-N.); (J.H.)
- Laboratorio de AgroBiotecnología, Universidad Politécnica de Pachuca, Carretera Pachuca-Cd. Sahagún, km 20, ExHacienda de Santa Bárbara, Zempoala 43830, Mexico;
- Servicio Nacional de Sanidad, Inocuidad y Calidad Agroalimentaria, Centro Nacional de Referencia Fitosanitaria, Tecamac 55740, Mexico
| | | | - Amanda Soares
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln 7647, New Zealand; (C.C.C.-C.); (A.S.); (E.A.P.-P.); (S.S.); (E.U.E.-N.); (J.H.)
| | - Emir Alejandro Padilla-Padilla
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln 7647, New Zealand; (C.C.C.-C.); (A.S.); (E.A.P.-P.); (S.S.); (E.U.E.-N.); (J.H.)
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand;
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca 04510, Mexico
| | - Miguel Angel Anducho-Reyes
- Laboratorio de AgroBiotecnología, Universidad Politécnica de Pachuca, Carretera Pachuca-Cd. Sahagún, km 20, ExHacienda de Santa Bárbara, Zempoala 43830, Mexico;
| | - Chris Brown
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin 9054, New Zealand;
| | - Sereyboth Soth
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln 7647, New Zealand; (C.C.C.-C.); (A.S.); (E.A.P.-P.); (S.S.); (E.U.E.-N.); (J.H.)
| | - Edgardo Ulises Esquivel-Naranjo
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln 7647, New Zealand; (C.C.C.-C.); (A.S.); (E.A.P.-P.); (S.S.); (E.U.E.-N.); (J.H.)
- Unit for Basic and Applied Microbiology, Faculty of Natural Sciences, Autonomous University of Queretaro, Queretaro 76230, Mexico
| | - John Hampton
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln 7647, New Zealand; (C.C.C.-C.); (A.S.); (E.A.P.-P.); (S.S.); (E.U.E.-N.); (J.H.)
| | - Artemio Mendoza-Mendoza
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln 7647, New Zealand; (C.C.C.-C.); (A.S.); (E.A.P.-P.); (S.S.); (E.U.E.-N.); (J.H.)
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Nuankaew S, Boonyuen N, Thumanu K, Pornputtapong N. Development of a machine learning model for systematics of Aspergillus section Nigri using synchrotron radiation-based fourier transform infrared spectroscopy. Heliyon 2024; 10:e26812. [PMID: 38439823 PMCID: PMC10909729 DOI: 10.1016/j.heliyon.2024.e26812] [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: 07/29/2023] [Revised: 02/01/2024] [Accepted: 02/20/2024] [Indexed: 03/06/2024] Open
Abstract
Aspergillus section Nigri (black aspergilli) fungi are economically important food spoilage agents. Some species in this section also produce harmful mycotoxins in food. However, it is remarkably difficult to identify this fungal group at the species level using morphological and chemical characteristics. The molecular approach for classification is preferable; however, it is time-consuming, making it inappropriate for rapid testing of large numbers of samples. To address this, we explored synchrotron radiation-based Fourier transform infrared microspectroscopy (SR-FTIR) as a rapid method for obtaining data suitable for species classification. SR-FTIR data were obtained from the mycelia/conidia of 22 black aspergilli species. The Convolutional Neural Network (CNN) approach, a supervised deep learning algorithm, was used with SR-FTIR data to classify black aspergilli at the species level. A subset of the data was used to train the CNN model, and the model classification performance was evaluated using the validation data subsets. The model demonstrated a 95.97% accuracy in species classification on the testing (blind) data subset. The technique presented herein could be an alternative method for identifying problematic black aspergilli in the food industry.
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Affiliation(s)
- Salilaporn Nuankaew
- Department of Biochemistry and Microbiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, 10330, Thailand
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, 12120, Thailand
| | - Nattawut Boonyuen
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, 12120, Thailand
| | - Kanjana Thumanu
- Synchrotron Light Research Institute (SLRI), Nakhon Ratchasima, 30000, Thailand
| | - Natapol Pornputtapong
- Department of Biochemistry and Microbiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, 10330, Thailand
- Center of Excellence in DNA Barcoding of Thai Medicinal Plants, Chulalongkorn University, Bangkok, 10330, Thailand
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Kunitake E, Kawaguchi T, Tani S. Independent, cooperative regulation of cellulolytic genes by paralogous transcription factors ClbR and ClbR2 in Aspergillus aculeatus. Biosci Biotechnol Biochem 2024; 88:212-219. [PMID: 37947258 DOI: 10.1093/bbb/zbad156] [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: 09/25/2023] [Accepted: 11/03/2023] [Indexed: 11/12/2023]
Abstract
The cellobiose-responsive regulator ClbR, a Zn(II)2Cys6 binuclear-cluster transcription factor, is a positive regulator of carbohydrate-active enzyme (CAZyme) genes responsive to cellulose in Aspergillus aculeatus. Because Zn(II)2Cys6 transcription factors tend to dimerize with proteins of the same family, we searched for a counterpart of ClbR and identified ClbR2, which is 42% identical to ClbR, as an interacting partner of ClbR by yeast two-hybrid screening. Genetic analyses suggested that ClbR and ClbR2 cooperatively regulate the expression of CAZyme genes in response to cellulose and 1,4-β-mannobiose in A. aculeatus. CAZyme genes under the control of the transcription factor ManR were regulated by ClbR and ClbR2, whereas those controlled by the transcription factor XlnR were regulated by ClbR, but not ClbR2. These findings suggest that ClbR participates in multiple regulatory pathways in A. aculeatus by altering an interacting factor.
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Affiliation(s)
- Emi Kunitake
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University , Sakai, Japan
- Graduate School of Bioresources, Mie University , Tsu, Japan
| | - Takashi Kawaguchi
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University , Sakai, Japan
- Graduate School of Agriculture, Osaka Metropolitan University , Sakai, Japan
| | - Shuji Tani
- Graduate School of Life and Environmental Sciences, Osaka Prefecture University , Sakai, Japan
- Graduate School of Agriculture, Osaka Metropolitan University , Sakai, Japan
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5
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Kerkaert JD, Huberman LB. Regulation of nutrient utilization in filamentous fungi. Appl Microbiol Biotechnol 2023; 107:5873-5898. [PMID: 37540250 PMCID: PMC10983054 DOI: 10.1007/s00253-023-12680-4] [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: 04/19/2023] [Revised: 06/29/2023] [Accepted: 07/04/2023] [Indexed: 08/05/2023]
Abstract
Organisms must accurately sense and respond to nutrients to survive. In filamentous fungi, accurate nutrient sensing is important in the establishment of fungal colonies and in continued, rapid growth for the exploitation of environmental resources. To ensure efficient nutrient utilization, fungi have evolved a combination of activating and repressing genetic networks to tightly regulate metabolic pathways and distinguish between preferred nutrients, which require minimal energy and resources to utilize, and nonpreferred nutrients, which have more energy-intensive catabolic requirements. Genes necessary for the utilization of nonpreferred carbon sources are activated by transcription factors that respond to the presence of the specific nutrient and repressed by transcription factors that respond to the presence of preferred carbohydrates. Utilization of nonpreferred nitrogen sources generally requires two transcription factors. Pathway-specific transcription factors respond to the presence of a specific nonpreferred nitrogen source, while another transcription factor activates genes in the absence of preferred nitrogen sources. In this review, we discuss the roles of transcription factors and upstream regulatory genes that respond to preferred and nonpreferred carbon and nitrogen sources and their roles in regulating carbon and nitrogen catabolism. KEY POINTS: • Interplay of activating and repressing transcriptional networks regulates catabolism. • Nutrient-specific activating transcriptional pathways provide metabolic specificity. • Repressing regulatory systems differentiate nutrients in mixed nutrient environments.
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Affiliation(s)
- Joshua D Kerkaert
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA
| | - Lori B Huberman
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Ithaca, NY, USA.
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Tseng WS, Lee MJ, Wu JA, Kuo SL, Chang SL, Huang SJ, Liu CT. Poly(butylene adipate-co-terephthalate) biodegradation by Purpureocillium lilacinum strain BA1S. Appl Microbiol Biotechnol 2023; 107:6057-6070. [PMID: 37526695 DOI: 10.1007/s00253-023-12704-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/18/2023] [Accepted: 07/21/2023] [Indexed: 08/02/2023]
Abstract
Poly(butylene adipate-co-terephthalate) (PBAT), a promising biodegradable aliphatic-aromatic copolyester material, can be applied as an alternative material to reduce the adverse effects of conventional plastics. However, the degradation of PBAT plastics in soil is time-consuming, and effective PBAT-degrading microorganisms have rarely been reported. In this study, the biodegradation properties of PBAT by an elite fungal strain and related mechanisms were elucidated. Four PBAT-degrading fungal strains were isolated from farmland soils, and Purpureocillium lilacinum strain BA1S showed a prominent degradation rate. It decomposed approximately 15 wt.% of the PBAT films 30 days after inoculation. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Liquid chromatography mass spectrometry (LC‒MS) were conducted to analyze the physicochemical properties and composition of the byproducts after biodegradation. In the presence of PBAT, the lipolytic enzyme activities of BA1S were remarkably induced, and its cutinase gene was also significantly upregulated. Of note, the utilization of PBAT in BA1S cells was closely correlated with intracellular cytochrome P450 (CYP) monooxygenase. Furthermore, CreA-mediated carbon catabolite repression was confirmed to be involved in regulating PBAT-degrading hydrolases and affected the degradation efficiency. This study provides new insight into the degradation of PBAT by elite fungal strains and increases knowledge on the mechanism, which can be applied to control the biodegradability of PBAT films in the future. KEY POINTS: • Purpureocillium lilacinum strain BA1S was isolated from farmland soils and degraded PBAT plastic films at a prominent rate. • The lipolytic enzyme activities of strain BA1S were induced during coculture with PBAT, and the cutinase gene was significantly upregulated during PBAT degradation. • CreA-mediated carbon catabolite repression of BA1S plays an essential role in regulating the expression of PBAT-degrading hydrolases.
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Affiliation(s)
- Wei-Sung Tseng
- Institute of Biotechnology, National Taiwan University, R412, No. 81, Chang-Xing St, Taipei, 106, Taiwan
| | - Min-Jia Lee
- Institute of Biotechnology, National Taiwan University, R412, No. 81, Chang-Xing St, Taipei, 106, Taiwan
| | - Jin-An Wu
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, 321 Kuang Fu Rd., Section 2, Hsinchu, Taiwan
| | - Shin-Liang Kuo
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, 321 Kuang Fu Rd., Section 2, Hsinchu, Taiwan
| | - Sheng-Lung Chang
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, 321 Kuang Fu Rd., Section 2, Hsinchu, Taiwan
| | - Shu-Jiuan Huang
- Material and Chemical Research Laboratories, Industrial Technology Research Institute, 321 Kuang Fu Rd., Section 2, Hsinchu, Taiwan
| | - Chi-Te Liu
- Institute of Biotechnology, National Taiwan University, R412, No. 81, Chang-Xing St, Taipei, 106, Taiwan.
- Department of Agricultural Chemistry, National Taiwan University No, 1, Sec. Roosevelt Road, Taipei, 106, Taiwan.
- Agricultural Biotechnology Research Center, Academia Sinica, No.128, Sec.2, Academia Rd., Nankang, Taipei, 115, Taiwan.
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Li J, Wiebenga A, Lipzen A, Ng V, Tejomurthula S, Zhang Y, Grigoriev IV, Peng M, de Vries RP. Comparative Genomics and Transcriptomics Analyses Reveal Divergent Plant Biomass-Degrading Strategies in Fungi. J Fungi (Basel) 2023; 9:860. [PMID: 37623631 PMCID: PMC10455118 DOI: 10.3390/jof9080860] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/15/2023] [Accepted: 08/16/2023] [Indexed: 08/26/2023] Open
Abstract
Plant biomass is one of the most abundant renewable carbon sources, which holds great potential for replacing current fossil-based production of fuels and chemicals. In nature, fungi can efficiently degrade plant polysaccharides by secreting a broad range of carbohydrate-active enzymes (CAZymes), such as cellulases, hemicellulases, and pectinases. Due to the crucial role of plant biomass-degrading (PBD) CAZymes in fungal growth and related biotechnology applications, investigation of their genomic diversity and transcriptional dynamics has attracted increasing attention. In this project, we systematically compared the genome content of PBD CAZymes in six taxonomically distant species, Aspergillus niger, Aspergillus nidulans, Penicillium subrubescens, Trichoderma reesei, Phanerochaete chrysosporium, and Dichomitus squalens, as well as their transcriptome profiles during growth on nine monosaccharides. Considerable genomic variation and remarkable transcriptomic diversity of CAZymes were identified, implying the preferred carbon source of these fungi and their different methods of transcription regulation. In addition, the specific carbon utilization ability inferred from genomics and transcriptomics was compared with fungal growth profiles on corresponding sugars, to improve our understanding of the conversion process. This study enhances our understanding of genomic and transcriptomic diversity of fungal plant polysaccharide-degrading enzymes and provides new insights into designing enzyme mixtures and metabolic engineering of fungi for related industrial applications.
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Affiliation(s)
- Jiajia Li
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; (J.L.); (M.P.)
| | - Ad Wiebenga
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; (J.L.); (M.P.)
| | - Anna Lipzen
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA; (A.L.); (V.N.); (S.T.); (Y.Z.); (I.V.G.)
| | - Vivian Ng
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA; (A.L.); (V.N.); (S.T.); (Y.Z.); (I.V.G.)
| | - Sravanthi Tejomurthula
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA; (A.L.); (V.N.); (S.T.); (Y.Z.); (I.V.G.)
| | - Yu Zhang
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA; (A.L.); (V.N.); (S.T.); (Y.Z.); (I.V.G.)
| | - Igor V. Grigoriev
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA; (A.L.); (V.N.); (S.T.); (Y.Z.); (I.V.G.)
- Plant and Microbial Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; (J.L.); (M.P.)
| | - Ronald P. de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; (J.L.); (M.P.)
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8
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Kun RS, Garrigues S, Peng M, Keymanesh K, Lipzen A, Ng V, Tejomurthula S, Grigoriev IV, de Vries RP. The transcriptional activator ClrB is crucial for the degradation of soybean hulls and guar gum in Aspergillus niger. Fungal Genet Biol 2023; 165:103781. [PMID: 36801368 DOI: 10.1016/j.fgb.2023.103781] [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: 08/29/2022] [Revised: 02/07/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023]
Abstract
Low-cost plant substrates, such as soybean hulls, are used for various industrial applications. Filamentous fungi are important producers of Carbohydrate Active enZymes (CAZymes) required for the degradation of these plant biomass substrates. CAZyme production is tightly regulated by several transcriptional activators and repressors. One such transcriptional activator is CLR-2/ClrB/ManR, which has been identified as a regulator of cellulase and mannanase production in several fungi. However, the regulatory network governing the expression of cellulase and mannanase encoding genes has been reported to differ between fungal species. Previous studies showed that Aspergillus niger ClrB is involved in the regulation of (hemi-)cellulose degradation, although its regulon has not yet been identified. To reveal its regulon, we cultivated an A. niger ΔclrB mutant and control strain on guar gum (a galactomannan-rich substrate) and soybean hulls (containing galactomannan, xylan, xyloglucan, pectin and cellulose) to identify the genes that are regulated by ClrB. Gene expression data and growth profiling showed that ClrB is indispensable for growth on cellulose and galactomannan and highly contributes to growth on xyloglucan in this fungus. Therefore, we show that A. niger ClrB is crucial for the utilization of guar gum and the agricultural substrate, soybean hulls. Moreover, we show that mannobiose is most likely the physiological inducer of ClrB in A. niger and not cellobiose, which is considered to be the inducer of N. crassa CLR-2 and A. nidulans ClrB.
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Affiliation(s)
- Roland S Kun
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Sandra Garrigues
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Keykhosrow Keymanesh
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States
| | - Anna Lipzen
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States
| | - Vivian Ng
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States
| | - Sravanthi Tejomurthula
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States
| | - Igor V Grigoriev
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720, United States
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands.
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9
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Identification of an l-Arabitol Transporter from Aspergillus niger. Biomolecules 2023; 13:biom13020188. [PMID: 36830558 PMCID: PMC9953744 DOI: 10.3390/biom13020188] [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: 12/23/2022] [Revised: 01/10/2023] [Accepted: 01/12/2023] [Indexed: 01/19/2023] Open
Abstract
l-arabitol is an intermediate of the pentose catabolic pathway in fungi but can also be used as a carbon source by many fungi, suggesting the presence of transporters for this polyol. In this study, an l-arabitol transporter, LatA, was identified in Aspergillus niger. Growth and expression profiles as well as sugar consumption analysis indicated that LatA only imports l-arabitol and is regulated by the arabinanolytic transcriptional activator AraR. Moreover, l-arabitol production from wheat bran was increased in a metabolically engineered A. niger mutant by the deletion of latA, indicating its potential for improving l-arabitol-producing cell factories. Phylogenetic analysis showed that homologs of LatA are widely conserved in fungi.
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Wu X, Zhang S, Zhao S, Dai L, Huang S, Liu X, Yu J, Wang L. Functional Specificity of Three α-Arabinofuranosidases from Different Glycoside Hydrolase Families in Aspergillus niger An76. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:5039-5048. [PMID: 35420820 DOI: 10.1021/acs.jafc.1c08388] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
α-l-Arabinofuranosidase (Abf), a debranching enzyme that can remove arabinose substituents from arabinoxylan, promotes the hydrolysis of hemicellulose in plant biomass. However, the functional specificity of Abfs from different glycoside hydrolase (GH) families on the digestion of arabinoxylan and their synergistic interaction with xylanase have not been systematically studied. In this work, we characterized three Abfs (AxhA, AbfB, and AbfC) from GH62, GH54, and GH51 families in Aspergillus niger An76. Quantitative transcriptional analysis showed that expression of the axhA gene was upregulated as a result of induction by xylose substrates, whereas expression of the abfB gene was mainly induced by arabinose. Recombinant AxhA, AbfB, and AbfC exhibited different hydrolytic performances. AxhA showed the highest catalytic activity toward wheat arabinoxylan (WAX) and tended to hydrolyze monosubstituted arabinofuranose units, whereas AbfB had higher catalytic activity on AN and debranched arabinan (DAN), having the ability to cope with mono- and disubstituted arabinofuranose units. Furthermore, AbfC had greater arabinofuranosidase activity on p-nitrophenyl-α-l-arabinofuranoside (pNP-AraF) than on other substrates. Moreover, three Abfs displayed obvious synergistic action with GH11 xylanase XynB against WAX and barley husk residues. The elucidation of the degradation mechanisms of Abfs will lay a theoretical foundation for the efficient industrialized transformation of arabinoxylans.
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Affiliation(s)
- Xiuyun Wu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, Shandong, China
- State Key Laboratory of Biological Fermentation Engineering of Beer, Qingdao 266000, Shandong, China
| | - Shu Zhang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, Shandong, China
| | - Sha Zhao
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, Shandong, China
| | - Lin Dai
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, Shandong, China
| | - Shuxia Huang
- State Key Laboratory of Biological Fermentation Engineering of Beer, Qingdao 266000, Shandong, China
| | - Xinli Liu
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, Shandong, China
| | - Junhong Yu
- State Key Laboratory of Biological Fermentation Engineering of Beer, Qingdao 266000, Shandong, China
| | - Lushan Wang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao 266237, Shandong, China
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11
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Carbohydrate esterase family 16 contains fungal hemicellulose acetyl esterases (HAEs) with varying specificity. N Biotechnol 2022; 70:28-38. [DOI: 10.1016/j.nbt.2022.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 04/05/2022] [Accepted: 04/05/2022] [Indexed: 11/18/2022]
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12
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Unraveling the regulation of sugar beet pulp utilization in the industrially relevant fungus Aspergillus niger. iScience 2022; 25:104065. [PMID: 35359804 PMCID: PMC8961234 DOI: 10.1016/j.isci.2022.104065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 02/07/2022] [Accepted: 03/09/2022] [Indexed: 11/21/2022] Open
Abstract
Efficient utilization of agro-industrial waste, such as sugar beet pulp, is crucial for the bio-based economy. The fungus Aspergillus niger possesses a wide array of enzymes that degrade complex plant biomass substrates, and several regulators have been reported to play a role in their production. The role of the regulators GaaR, AraR, and RhaR in sugar beet pectin degradation has previously been reported. However, genetic regulation of the degradation of sugar beet pulp has not been assessed in detail. In this study, we generated a set of single and combinatorial deletion mutants targeting the pectinolytic regulators GaaR, AraR, RhaR, and GalX as well as the (hemi-)cellulolytic regulators XlnR and ClrB to address their relative contribution to the utilization of sugar beet pulp. We show that A. niger has a flexible regulatory network, adapting to the utilization of (hemi-)cellulose at early timepoints when pectin degradation is impaired. Major sugar beet pulp components are sequentially utilized by A. niger Contribution of major regulators toward sugar beet pulp utilization was compared Deletion of araR and clrB showed high impact on growth after 8 and 24 h, respectively
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Meng J, Németh Z, Peng M, Fekete E, Garrigues S, Lipzen A, Ng V, Savage E, Zhang Y, Grigoriev IV, Mäkelä MR, Karaffa L, de Vries RP. GalR, GalX and AraR co-regulate d-galactose and l-arabinose utilization in Aspergillus nidulans. Microb Biotechnol 2022; 15:1839-1851. [PMID: 35213794 PMCID: PMC9151342 DOI: 10.1111/1751-7915.14025] [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: 11/25/2021] [Revised: 02/09/2022] [Accepted: 02/10/2022] [Indexed: 11/27/2022] Open
Abstract
Filamentous fungi produce a wide variety of enzymes in order to efficiently degrade plant cell wall polysaccharides. The production of these enzymes is controlled by transcriptional regulators, which also control the catabolic pathways that convert the released monosaccharides. Two transcriptional regulators, GalX and GalR, control d-galactose utilization in the model filamentous fungus Aspergillus nidulans, while the arabinanolytic regulator AraR regulates l-arabinose catabolism. d-Galactose and l-arabinose are commonly found together in polysaccharides, such as arabinogalactan, xylan and rhamnogalacturonan I. Therefore, the catabolic pathways that convert d-galactose and l-arabinose are often also likely to be active simultaneously. In this study, we investigated the interaction between GalX, GalR and AraR in d-galactose and l-arabinose catabolism. For this, we generated single, double and triple mutants of the three regulators, and analysed their growth and enzyme and gene expression profiles. Our results clearly demonstrated that GalX, GalR and AraR co-regulate d-galactose catabolism in A. nidulans. GalX has a prominent role on the regulation of genes of d-galactose oxido-reductive pathway, while AraR can compensate for the absence of GalR and/or GalX.
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Affiliation(s)
- Jiali Meng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, Utrecht, 3584 CT, The Netherlands
| | - Zoltán Németh
- Department of Biochemical Engineering, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1., Debrecen, H-4032, Hungary
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, Utrecht, 3584 CT, The Netherlands
| | - Erzsébet Fekete
- Department of Biochemical Engineering, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1., Debrecen, H-4032, Hungary
| | - Sandra Garrigues
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, Utrecht, 3584 CT, The Netherlands
| | - Anna Lipzen
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Vivian Ng
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Emily Savage
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Yu Zhang
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Igor V Grigoriev
- Lawrence Berkeley National Laboratory, US Department of Energy Joint Genome Institute, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Miia R Mäkelä
- Department of Microbiology, University of Helsinki, Viikinkaari 9, Helsinki, 00790, Finland
| | - Levente Karaffa
- Department of Biochemical Engineering, Faculty of Science and Technology, University of Debrecen, Egyetem tér 1., Debrecen, H-4032, Hungary.,Institute of Metagenomics, University of Debrecen, Egyetem tér 1., Debrecen, H-4032, Hungary
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, Utrecht, 3584 CT, The Netherlands
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14
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Chroumpi T, Martínez-Reyes N, Kun RS, Peng M, Lipzen A, Ng V, Tejomurthula S, Zhang Y, Grigoriev IV, Mäkelä MR, de Vries RP, Garrigues S. Detailed analysis of the D-galactose catabolic pathways in Aspergillus niger reveals complexity at both metabolic and regulatory level. Fungal Genet Biol 2022; 159:103670. [PMID: 35121171 DOI: 10.1016/j.fgb.2022.103670] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 12/22/2021] [Accepted: 01/28/2022] [Indexed: 01/23/2023]
Abstract
The current impetus towards a sustainable bio-based economy has accelerated research to better understand the mechanisms through which filamentous fungi convert plant biomass, a valuable feedstock for biotechnological applications. Several transcription factors have been reported to control the polysaccharide degradation and metabolism of the resulting sugars in fungi. However, little is known about their individual contributions, interactions and crosstalk. D-galactose is a hexose sugar present mainly in hemicellulose and pectin in plant biomass. Here, we study D-galactose conversion by Aspergillus niger and describe the involvement of the arabinanolytic and xylanolytic activators AraR and XlnR, in addition to the D-galactose-responsive regulator GalX. Our results deepen the understanding of the complexity of the filamentous fungal regulatory network for plant biomass degradation and sugar catabolism, and facilitate the generation of more efficient plant biomass-degrading strains for biotechnological applications.
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Affiliation(s)
- Tania Chroumpi
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Natalia Martínez-Reyes
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Roland S Kun
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Vivian Ng
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Sravanthi Tejomurthula
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Yu Zhang
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States
| | - Igor V Grigoriev
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, United States; Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, United States
| | - Miia R Mäkelä
- Department of Microbiology, P.O. Box 56, Viikinkaari 9, University of Helsinki, Helsinki, Finland
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands.
| | - Sandra Garrigues
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
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Meng J, Chroumpi T, Mäkelä MR, de Vries RP. Xylitol production from plant biomass by Aspergillus niger through metabolic engineering. BIORESOURCE TECHNOLOGY 2022; 344:126199. [PMID: 34710597 DOI: 10.1016/j.biortech.2021.126199] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 05/12/2023]
Abstract
Xylitol is widely used in the food and pharmaceutical industries as a valuable commodity product. Biotechnological production of xylitol from lignocellulosic biomass by microorganisms is a promising alternative option to chemical synthesis or bioconversion from D-xylose. In this study, four metabolic mutants of Aspergillus niger were constructed and evaluated for xylitol accumulation from D-xylose and lignocellulosic biomass. All mutants had strongly increased xylitol production from pure D-xylose, beechwood xylan, wheat bran and cotton seed hulls compared to the reference strain, but not from several other feed stocks. The triple mutant ΔladAΔxdhAΔsdhA showed the best performance in xylitol production from wheat bran and cotton seed hulls. This study demonstrated the large potential of A. niger for xylitol production directly from lignocellulosic biomass by metabolic engineering.
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Affiliation(s)
- Jiali Meng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Tania Chroumpi
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Miia R Mäkelä
- Department of Microbiology, University of Helsinki, Viikinkaari 9, 00790 Helsinki, Finland
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands.
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Peng M, de Vries RP. Machine learning prediction of novel pectinolytic enzymes in Aspergillus niger through integrating heterogeneous (post-) genomics data. Microb Genom 2021; 7. [PMID: 34874247 PMCID: PMC8767319 DOI: 10.1099/mgen.0.000674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Pectinolytic enzymes are a variety of enzymes involved in breaking down pectin, a complex and abundant plant cell-wall polysaccharide. In nature, pectinolytic enzymes play an essential role in allowing bacteria and fungi to depolymerize and utilize pectin. In addition, pectinases have been widely applied in various industries, such as the food, wine, textile, paper and pulp industries. Due to their important biological function and increasing industrial potential, discovery of novel pectinolytic enzymes has received global interest. However, traditional enzyme characterization relies heavily on biochemical experiments, which are time consuming, laborious and expensive. To accelerate identification of novel pectinolytic enzymes, an automatic approach is needed. We developed a machine learning (ML) approach for predicting pectinases in the industrial workhorse fungus, Aspergillus niger. The prediction integrated a diverse range of features, including evolutionary profile, gene expression, transcriptional regulation and biochemical characteristics. Results on both the training and the independent testing dataset showed that our method achieved over 90 % accuracy, and recalled over 60 % of pectinolytic genes. Application of the ML model on the A. niger genome led to the identification of 83 pectinases, covering both previously described pectinases and novel pectinases that do not belong to any known pectinolytic enzyme family. Our study demonstrated the tremendous potential of ML in discovery of new industrial enzymes through integrating heterogeneous (post-) genomimcs data.
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Affiliation(s)
- Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
- *Correspondence: Mao Peng,
| | - Ronald P. de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, & Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
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Chroumpi T, Peng M, Aguilar‐Pontes MV, Müller A, Wang M, Yan J, Lipzen A, Ng V, Grigoriev IV, Mäkelä MR, de Vries RP. Revisiting a 'simple' fungal metabolic pathway reveals redundancy, complexity and diversity. Microb Biotechnol 2021; 14:2525-2537. [PMID: 33666344 PMCID: PMC8601170 DOI: 10.1111/1751-7915.13790] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 02/17/2021] [Accepted: 02/17/2021] [Indexed: 01/29/2023] Open
Abstract
Next to d-glucose, the pentoses l-arabinose and d-xylose are the main monosaccharide components of plant cell wall polysaccharides and are therefore of major importance in biotechnological applications that use plant biomass as a substrate. Pentose catabolism is one of the best-studied pathways of primary metabolism of Aspergillus niger, and an initial outline of this pathway with individual enzymes covering each step of the pathway has been previously established. However, although growth on l-arabinose and/or d-xylose of most pentose catabolic pathway (PCP) single deletion mutants of A. niger has been shown to be negatively affected, it was not abolished, suggesting the involvement of additional enzymes. Detailed analysis of the single deletion mutants of the known A. niger PCP genes led to the identification of additional genes involved in the pathway. These results reveal a high level of complexity and redundancy in this pathway, emphasizing the need for a comprehensive understanding of metabolic pathways before entering metabolic engineering of such pathways for the generation of more efficient fungal cell factories.
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Affiliation(s)
- Tania Chroumpi
- Fungal PhysiologyWesterdijk Fungal Biodiversity Institute & Fungal Molecular PhysiologyUtrecht UniversityUppsalalaan 8Utrecht3584 CTThe Netherlands
| | - Mao Peng
- Fungal PhysiologyWesterdijk Fungal Biodiversity Institute & Fungal Molecular PhysiologyUtrecht UniversityUppsalalaan 8Utrecht3584 CTThe Netherlands
| | - Maria Victoria Aguilar‐Pontes
- Fungal PhysiologyWesterdijk Fungal Biodiversity Institute & Fungal Molecular PhysiologyUtrecht UniversityUppsalalaan 8Utrecht3584 CTThe Netherlands
- Present address:
Centre for Structural and Functional GenomicsConcordia University7141 Sherbrooke Street WestMontrealQCH4B1R6Canada
| | - Astrid Müller
- Fungal PhysiologyWesterdijk Fungal Biodiversity Institute & Fungal Molecular PhysiologyUtrecht UniversityUppsalalaan 8Utrecht3584 CTThe Netherlands
| | - Mei Wang
- US Department of Energy Joint Genome InstituteLawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA94720USA
| | - Juying Yan
- US Department of Energy Joint Genome InstituteLawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA94720USA
| | - Anna Lipzen
- US Department of Energy Joint Genome InstituteLawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA94720USA
| | - Vivian Ng
- US Department of Energy Joint Genome InstituteLawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA94720USA
| | - Igor V. Grigoriev
- US Department of Energy Joint Genome InstituteLawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCA94720USA
- Department of Plant and Microbial BiologyUniversity of CaliforniaBerkeleyCA94720USA
| | - Miia R. Mäkelä
- Department of MicrobiologyUniversity of HelsinkiP.O. Box 56Viikinkaari 9HelsinkiFinland
| | - Ronald P. de Vries
- Fungal PhysiologyWesterdijk Fungal Biodiversity Institute & Fungal Molecular PhysiologyUtrecht UniversityUppsalalaan 8Utrecht3584 CTThe Netherlands
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Kun RS, Garrigues S, Di Falco M, Tsang A, de Vries RP. Blocking utilization of major plant biomass polysaccharides leads Aspergillus niger towards utilization of minor components. Microb Biotechnol 2021; 14:1683-1698. [PMID: 34114741 PMCID: PMC8313289 DOI: 10.1111/1751-7915.13835] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 05/08/2021] [Accepted: 05/10/2021] [Indexed: 11/28/2022] Open
Abstract
Fungi produce a wide range of enzymes that allow them to grow on diverse plant biomass. Wheat bran is a low-cost substrate with high potential for biotechnological applications. It mainly contains cellulose and (arabino)xylan, as well as starch, proteins, lipids and lignin to a lesser extent. In this study, we dissected the regulatory network governing wheat bran degradation in Aspergillus niger to assess the relative contribution of the regulators to the utilization of this plant biomass substrate. Deletion of genes encoding transcription factors involved in (hemi-)cellulose utilization (XlnR, AraR, ClrA and ClrB) individually and in combination significantly reduced production of polysaccharide-degrading enzymes, but retained substantial growth on wheat bran. Proteomic analysis suggested the ability of A. niger to grow on other carbon components, such as starch, which was confirmed by the additional deletion of the amylolytic regulator AmyR. Growth was further reduced but not impaired, indicating that other minor components provide sufficient energy for residual growth, displaying the flexibility of A. niger, and likely other fungi, in carbon utilization. Better understanding of the complexity and flexibility of fungal regulatory networks will facilitate the generation of more efficient fungal cell factories that use plant biomass as a substrate.
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Affiliation(s)
- Roland S. Kun
- Fungal PhysiologyWesterdijk Fungal Biodiversity Institute & Fungal Molecular PhysiologyUtrecht UniversityUppsalalaan 8Utrecht3584 CTThe Netherlands
| | - Sandra Garrigues
- Fungal PhysiologyWesterdijk Fungal Biodiversity Institute & Fungal Molecular PhysiologyUtrecht UniversityUppsalalaan 8Utrecht3584 CTThe Netherlands
| | - Marcos Di Falco
- Centre for Structural and Functional GenomicsConcordia University7141 Sherbrooke Street WestMontrealQCH4B 1R6Canada
| | - Adrian Tsang
- Centre for Structural and Functional GenomicsConcordia University7141 Sherbrooke Street WestMontrealQCH4B 1R6Canada
| | - Ronald P. de Vries
- Fungal PhysiologyWesterdijk Fungal Biodiversity Institute & Fungal Molecular PhysiologyUtrecht UniversityUppsalalaan 8Utrecht3584 CTThe Netherlands
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Cao L, Liao L, Su C, Mo T, Zhu F, Qin R, Li R. Metagenomic analysis revealed the microbiota and metabolic function during co-composting of food waste and residual sludge for nitrogen and phosphorus transformation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 773:145561. [PMID: 33592475 DOI: 10.1016/j.scitotenv.2021.145561] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/25/2021] [Accepted: 01/27/2021] [Indexed: 06/12/2023]
Abstract
This paper used bagasse as a composting additive and bulking agent in order to investigate the aerobic composting process of food waste and residual sludge. Accordingly, the variations of nitrogen and phosphorus nutrients, microbiota and metabolic function during the composting process were systematically explored. Three piles with residual sludge, food waste and bagasse mass ratios of 1:1:1, 2:1:1 and 4:1:1 were set. The ammonia nitrogen content in the three compost piles were 3.18 mg/g, 4.68 mg/g and 5.84 mg/g at the end of composting. The final available phosphorus content of the three piles were 3.42 mg/g, 6.70 mg/g and 11.21 mg/g, respectively. X-ray photoelectron spectroscopy (XPS) analysis showed that absorption peaks attributed to amines, amino acids and amides appeared in the 1:1:1 pile. Metagenomic analysis of the glycolysis and ammonia transformation pathways showed that the total relative abundance of key enzyme genes for the conversion of glucose to glucose-6-phosphate in the three plies were 0.326%, 0.213% and 0.248%, respectively. The total relative abundance of 2 glutamate dehydrogenase (GDH2), glud1-2 and E1,4,1,4 dehydrogenases in the three piles was 0.125%, 0.151% and 0.160%, respectively, as the main enzymes for the mutual conversion of ammonia and glutamate.
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Affiliation(s)
- Linlin Cao
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin 541004, PR China
| | - Liming Liao
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin 541004, PR China
| | - Chengyuan Su
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin 541004, PR China; University Key Laboratory of Karst Ecology and Environmental Change of Guangxi Province (Guangxi Normal University), 15 Yucai Road, Guilin 541004, PR China.
| | - Tianhao Mo
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin 541004, PR China
| | - Fenghua Zhu
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin 541004, PR China
| | - Ronghua Qin
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin 541004, PR China
| | - Ruting Li
- Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, 15 Yucai Road, Guilin 541004, PR China
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Terebieniec A, Chroumpi T, Dilokpimol A, Aguilar-Pontes MV, Mäkelä MR, de Vries RP. Characterization of d-xylose reductase, XyrB, from Aspergillus niger. BIOTECHNOLOGY REPORTS 2021; 30:e00610. [PMID: 33842213 PMCID: PMC8020424 DOI: 10.1016/j.btre.2021.e00610] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/21/2021] [Accepted: 03/12/2021] [Indexed: 11/09/2022]
Abstract
XyrB is involved in conversion of d-xylose and l-arabinose in A. niger. The xyrB expression is induced both by d-xylose and l-arabinose. XyrB expression is controlled by xlnR and araR regulators.
d-xylose reductase is a member of the aldo-keto reductase family, and is involved in d-xylose and l-arabinose conversion through the Pentose Catabolic Pathway (PCP) in fungi. In this study, we biochemically characterized a newly identified second d-xylose reductase (XyrB) from Aspergillus niger. This NADPH-dependent reductase is able to efficiently convert d-xylose and l-arabinose, and it has the highest affinity for these sugars of all currently known fungal pentose reductases. A combination of biochemical data, transcriptomics and phylogenetic analysis further illustrated the role of XyrB in the PCP. Enzymes: D-xylose reductase (EC 1.1.1.307), L-arabinose reductase (EC 1.1.1.21).
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21
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Tanaka M, Gomi K. Induction and Repression of Hydrolase Genes in Aspergillus oryzae. Front Microbiol 2021; 12:677603. [PMID: 34108952 PMCID: PMC8180590 DOI: 10.3389/fmicb.2021.677603] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 04/26/2021] [Indexed: 11/13/2022] Open
Abstract
The filamentous fungus Aspergillus oryzae, also known as yellow koji mold, produces high levels of hydrolases such as amylolytic and proteolytic enzymes. This property of producing large amounts of hydrolases is one of the reasons why A. oryzae has been used in the production of traditional Japanese fermented foods and beverages. A wide variety of hydrolases produced by A. oryzae have been used in the food industry. The expression of hydrolase genes is induced by the presence of certain substrates, and various transcription factors that regulate such expression have been identified. In contrast, in the presence of glucose, the expression of the glycosyl hydrolase gene is generally repressed by carbon catabolite repression (CCR), which is mediated by the transcription factor CreA and ubiquitination/deubiquitination factors. In this review, we present the current knowledge on the regulation of hydrolase gene expression, including CCR, in A. oryzae.
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Affiliation(s)
- Mizuki Tanaka
- Biomolecular Engineering Laboratory, School of Food and Nutritional Science, University of Shizuoka, Shizuoka, Japan
| | - Katsuya Gomi
- Laboratory of Fermentation Microbiology, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan
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22
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Draft genome of the glucose tolerant β-glucosidase producing rare Aspergillus unguis reveals complete cellulolytic machinery with multiple beta-glucosidase genes. Fungal Genet Biol 2021; 151:103551. [PMID: 33737204 DOI: 10.1016/j.fgb.2021.103551] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 02/24/2021] [Accepted: 03/07/2021] [Indexed: 11/20/2022]
Abstract
Draft genome sequence of the glucose tolerant beta glucosidase (GT-BGL) producing rare fungus Aspergillus unguis NII 08,123 was generated through Next Generation Sequencing (NGS). The genome size of the fungus was estimated to be 37.1 Mb. A total of 3116 contigs were assembled using SPades, and 15,161 proteins were predicted using AUGUSTUS 3.1. Among them, 13,850 proteins were annotated using UniProt. Distribution of CAZyme genes specifically those encoding lignocellulose degrading enzymes were analyzed and compared with those from the industrial cellulase producer Trichoderma reesei in view of the huge differences in detectable enzyme activities between the fungi, despite the ability of A. unguis to grow on lignocellulose as sole carbon source. Full length gene sequence of the inducible GT-BGL could be identified through tracing back from peptide mass fingerprint. A total of 403 CAZymes were predicted from the genome, which includes 232 glycoside hydrolases (GHs), 12 carbohydrate esterases (CEs), 109 glycosyl transferases (GTs), 15 polysaccharide lyases (PLs), and 35 genes with auxiliary activities (AAs). The high level of zinc finger motif containing transcription factors could possibly hint a tight regulation of the cellulolytic machinery, which may also explain the low cellulase activities even when a complete repertoire of cellulase degrading enzyme genes are present in the fungus.
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23
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Chroumpi T, Peng M, Markillie LM, Mitchell HD, Nicora CD, Hutchinson CM, Paurus V, Tolic N, Clendinen CS, Orr G, Baker SE, Mäkelä MR, de Vries RP. Re-routing of Sugar Catabolism Provides a Better Insight Into Fungal Flexibility in Using Plant Biomass-Derived Monomers as Substrates. Front Bioeng Biotechnol 2021; 9:644216. [PMID: 33763411 PMCID: PMC7982397 DOI: 10.3389/fbioe.2021.644216] [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: 12/20/2020] [Accepted: 02/16/2021] [Indexed: 11/13/2022] Open
Abstract
The filamentous ascomycete Aspergillus niger has received increasing interest as a cell factory, being able to efficiently degrade plant cell wall polysaccharides as well as having an extensive metabolism to convert the released monosaccharides into value added compounds. The pentoses D-xylose and L-arabinose are the most abundant monosaccharides in plant biomass after the hexose D-glucose, being major constituents of xylan, pectin and xyloglucan. In this study, the influence of selected pentose catabolic pathway (PCP) deletion strains on growth on plant biomass and re-routing of sugar catabolism was addressed to gain a better understanding of the flexibility of this fungus in using plant biomass-derived monomers. The transcriptome, metabolome and proteome response of three PCP mutant strains, ΔlarAΔxyrAΔxyrB, ΔladAΔxdhAΔsdhA and ΔxkiA, grown on wheat bran (WB) and sugar beet pulp (SBP), was evaluated. Our results showed that despite the absolute impact of these PCP mutations on pure pentose sugars, they are not as critical for growth of A. niger on more complex biomass substrates, such as WB and SBP. However, significant phenotypic variation was observed between the two biomass substrates, but also between the different PCP mutants. This shows that the high sugar heterogeneity of these substrates in combination with the high complexity and adaptability of the fungal sugar metabolism allow for activation of alternative strategies to support growth.
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Affiliation(s)
- Tania Chroumpi
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, Netherlands
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, Netherlands
| | - Lye Meng Markillie
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Hugh D Mitchell
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Carrie D Nicora
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Chelsea M Hutchinson
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Vanessa Paurus
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Nikola Tolic
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Chaevien S Clendinen
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Galya Orr
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Scott E Baker
- Environmental Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, WA, United States
| | - Miia R Mäkelä
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, Netherlands.,Department of Microbiology, University of Helsinki, Helsinki, Finland
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, Netherlands
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24
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Yamashita M, Tsujikami M, Murata S, Kobayashi T, Shimizu M, Kato M. Artificial AmyR::XlnR transcription factor induces α-amylase production in response to non-edible xylan-containing hemicellulosic biomass. Enzyme Microb Technol 2021; 145:109762. [PMID: 33750542 DOI: 10.1016/j.enzmictec.2021.109762] [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] [Received: 10/22/2020] [Revised: 01/22/2021] [Accepted: 02/04/2021] [Indexed: 12/17/2022]
Abstract
Filamentous fungi belonging to the Aspergillus genus are one of the most favored microorganisms for industrial enzyme production because they can secrete large amounts of proteins into the culture medium. α-Amylase, an enzyme produced by Aspergillus species, is important for food and industrial applications. The production of α-amylase is induced by starch, mainly obtained from the edible biomass; however, the increasing demand for foods is limiting the application of the latter. Therefore, it is expected that using the non-edible biomass, such as rice straw, could improve the competition for industrial application starch containing resources. The transcription factor AmyR activates the transcription of amylolytic enzyme genes, while the transcription factor XlnR activates the transcription of xylanolytic enzyme genes in response to xylose. In this study, we aimed to construct an artificial AmyR::XlnR transcription factor (AXTF) by replacing the DNA-binding domain (1-159 amino acids) of XlnR with that (1-68 aa) of AmyR, which is capable of inducing amylolytic enzyme production in response to xylan-containing hemicellulosic biomass. The chimeric transcription factor AXTF was constructed and expressed using the gapA promoter in the amyR-deficient mutant strain SA1. When the AXTF strain was cultured in the minimal medium containing xylose as the carbon source, the amyB, amyF, agdB, and agdE transcription levels were 41.1-, 11.3-, 37.9-, and 23.7-fold higher, respectively, than those of the wild-type strain. The α-amylase and α-glucosidase activities in the culture supernatant of the AXTF strain grown with xylose for 48 h were 696.6 and 536.1 U/mL, respectively, while these activities were not detected in the culture supernatant of the wild-type and SA1 strains. When rice straw hydrolysate was used as a carbon source, the α-amylase and α-glucosidase activities were 590.2 and 362.7 U/mL, respectively. Thus, we successfully generated an Aspergillus nidulans strain showing amylolytic enzyme production in response to non-edible xylan-containing hemicellulosic biomass by transforming it with the chimeric transcription factor AXTF. Furthermore, the use of genes encoding engineered transcription factors is advantageous because introducing such genes into an industrial Aspergillus strain has similar simultaneous effects on multiple amylase genes controlled by AmyR.
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Affiliation(s)
- Miharu Yamashita
- Faculty of Agriculture, Meijo University, Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Masaya Tsujikami
- Faculty of Agriculture, Meijo University, Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Shunsuke Murata
- Faculty of Agriculture, Meijo University, Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Tetsuo Kobayashi
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
| | - Motoyuki Shimizu
- Faculty of Agriculture, Meijo University, Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Masashi Kato
- Faculty of Agriculture, Meijo University, Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-8502, Japan.
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25
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Wu VW, Thieme N, Huberman LB, Dietschmann A, Kowbel DJ, Lee J, Calhoun S, Singan VR, Lipzen A, Xiong Y, Monti R, Blow MJ, O'Malley RC, Grigoriev IV, Benz JP, Glass NL. The regulatory and transcriptional landscape associated with carbon utilization in a filamentous fungus. Proc Natl Acad Sci U S A 2020; 117:6003-6013. [PMID: 32111691 PMCID: PMC7084071 DOI: 10.1073/pnas.1915611117] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Filamentous fungi, such as Neurospora crassa, are very efficient in deconstructing plant biomass by the secretion of an arsenal of plant cell wall-degrading enzymes, by remodeling metabolism to accommodate production of secreted enzymes, and by enabling transport and intracellular utilization of plant biomass components. Although a number of enzymes and transcriptional regulators involved in plant biomass utilization have been identified, how filamentous fungi sense and integrate nutritional information encoded in the plant cell wall into a regulatory hierarchy for optimal utilization of complex carbon sources is not understood. Here, we performed transcriptional profiling of N. crassa on 40 different carbon sources, including plant biomass, to provide data on how fungi sense simple to complex carbohydrates. From these data, we identified regulatory factors in N. crassa and characterized one (PDR-2) associated with pectin utilization and one with pectin/hemicellulose utilization (ARA-1). Using in vitro DNA affinity purification sequencing (DAP-seq), we identified direct targets of transcription factors involved in regulating genes encoding plant cell wall-degrading enzymes. In particular, our data clarified the role of the transcription factor VIB-1 in the regulation of genes encoding plant cell wall-degrading enzymes and nutrient scavenging and revealed a major role of the carbon catabolite repressor CRE-1 in regulating the expression of major facilitator transporter genes. These data contribute to a more complete understanding of cross talk between transcription factors and their target genes, which are involved in regulating nutrient sensing and plant biomass utilization on a global level.
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Affiliation(s)
- Vincent W Wu
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
- Energy Biosciences Institute, University of California, Berkeley, CA 94704
| | - Nils Thieme
- Holzforschung München, Technical University of Munich School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Lori B Huberman
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
- Energy Biosciences Institute, University of California, Berkeley, CA 94704
| | - Axel Dietschmann
- Holzforschung München, Technical University of Munich School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - David J Kowbel
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
| | - Juna Lee
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Sara Calhoun
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Vasanth R Singan
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Yi Xiong
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
- Energy Biosciences Institute, University of California, Berkeley, CA 94704
| | - Remo Monti
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Matthew J Blow
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Ronan C O'Malley
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Igor V Grigoriev
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720
- US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - J Philipp Benz
- Holzforschung München, Technical University of Munich School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720;
- Energy Biosciences Institute, University of California, Berkeley, CA 94704
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
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26
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de Vries RP, Mäkelä MR. Genomic and Postgenomic Diversity of Fungal Plant Biomass Degradation Approaches. Trends Microbiol 2020; 28:487-499. [PMID: 32396827 DOI: 10.1016/j.tim.2020.01.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/15/2019] [Accepted: 01/16/2020] [Indexed: 10/25/2022]
Abstract
Plant biomass degradation by fungi is a widely studied and applied field of science, due to its relevance for the global carbon cycle and many biotechnological applications. Before the genome era, many of the in-depth studies focused on a relatively small number of species, whereas now, many species can be addressed in detail, revealing the large variety in the approach used by fungi to degrade plant biomass. This variation is found at many levels and includes genomic adaptation to the preferred biomass component, but also different approaches to degrade this component by diverse sets of activities encoded in the genome. Even larger differences have been observed using transcriptome and proteome studies, even between closely related species, suggesting a high level of adaptation in individual species. A better understanding of the drivers of this diversity could be highly valuable in developing more efficient biotechnology approaches for the enzymatic conversion of plant biomass.
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Affiliation(s)
- Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands.
| | - Miia R Mäkelä
- Department of Microbiology, University of Helsinki, Helsinki, Finland
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27
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Kun RS, Meng J, Salazar-Cerezo S, Mäkelä MR, de Vries RP, Garrigues S. CRISPR/Cas9 facilitates rapid generation of constitutive forms of transcription factors in Aspergillus niger through specific on-site genomic mutations resulting in increased saccharification of plant biomass. Enzyme Microb Technol 2020; 136:109508. [PMID: 32331715 DOI: 10.1016/j.enzmictec.2020.109508] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 12/16/2019] [Accepted: 01/08/2020] [Indexed: 12/26/2022]
Abstract
The CRISPR/Cas9 system has been successfully applied for gene editing in filamentous fungi. Previous studies reported that single stranded oligonucleotides can be used as repair templates to induce point mutations in some filamentous fungi belonging to genus Aspergillus. In Aspergillus niger, extensive research has been performed on regulation of plant biomass degradation, addressing transcription factors such as XlnR or GaaR, involved in (hemi-)cellulose and pectin utilization, respectively. Single nucleotide mutations leading to constitutively active forms of XlnR and GaaR have been previously reported. However, the mutations were performed by the introduction of versions obtained through site-directed or UV-mutagenesis into the genome. Here we report a more time- and cost-efficient approach to obtaining constitutively active versions by application of the CRISPR/Cas9 system to generate the desired mutation on-site in the A. niger genome. This was also achieved using only 60-mer single stranded oligonucleotides, shorter than the previously reported 90-mer strands. In this study, we show that CRISPR/Cas9 can also be used to efficiently change functional properties of the proteins encoded by the target gene by on-site genomic mutations in A. niger. The obtained strains with constitutively active XlnR and GaaR versions resulted in increased production of plant biomass degrading enzymes and improved release of d-xylose and l-arabinose from wheat bran, and d-galacturonic acid from sugar beet pulp.
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Affiliation(s)
- Roland S Kun
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Jiali Meng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Sonia Salazar-Cerezo
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Miia R Mäkelä
- Fungal Genetics and Biotechnology, Department of Microbiology, University of Helsinki, Viikinkaari 9, 00790 Helsinki, Finland
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands.
| | - Sandra Garrigues
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
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28
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Khosravi C, Kowalczyk JE, Chroumpi T, Battaglia E, Aguilar Pontes MV, Peng M, Wiebenga A, Ng V, Lipzen A, He G, Bauer D, Grigoriev IV, de Vries RP. Transcriptome analysis of Aspergillus niger xlnR and xkiA mutants grown on corn Stover and soybean hulls reveals a highly complex regulatory network. BMC Genomics 2019; 20:853. [PMID: 31726994 PMCID: PMC6854810 DOI: 10.1186/s12864-019-6235-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 10/28/2019] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Enzymatic plant biomass degradation by fungi is a highly complex process and one of the leading challenges in developing a biobased economy. Some industrial fungi (e.g. Aspergillus niger) have a long history of use with respect to plant biomass degradation and for that reason have become 'model' species for this topic. A. niger is a major industrial enzyme producer that has a broad ability to degrade plant based polysaccharides. A. niger wild-type, the (hemi-)cellulolytic regulator (xlnR) and xylulokinase (xkiA1) mutant strains were grown on a monocot (corn stover, CS) and dicot (soybean hulls, SBH) substrate. The xkiA1 mutant is unable to utilize the pentoses D-xylose and L-arabinose and the polysaccharide xylan, and was previously shown to accumulate inducers for the (hemi-)cellulolytic transcriptional activator XlnR and the arabinanolytic transcriptional activator AraR in the presence of pentoses, resulting in overexpression of their target genes. The xlnR mutant has reduced growth on xylan and down-regulation of its target genes. The mutants therefore have a similar phenotype on xylan, but an opposite transcriptional effect. D-xylose and L-arabinose are the most abundant monosaccharides after D-glucose in nearly all plant-derived biomass materials. In this study we evaluated the effect of the xlnR and xkiA1 mutation during growth on two pentose-rich substrates by transcriptome analysis. RESULTS Particular attention was given to CAZymes, metabolic pathways and transcription factors related to the plant biomass degradation. Genes coding for the main enzymes involved in plant biomass degradation were down-regulated at the beginning of the growth on CS and SBH. However, at a later time point, significant differences were found in the expression profiles of both mutants on CS compared to SBH. CONCLUSION This study demonstrates the high complexity of the plant biomass degradation process by fungi, by showing that mutant strains with fairly straightforward phenotypes on pure mono- and polysaccharides, have much less clear-cut phenotypes and transcriptomes on crude plant biomass.
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Affiliation(s)
- Claire Khosravi
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Joanna E. Kowalczyk
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Tania Chroumpi
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Evy Battaglia
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Maria-Victoria Aguilar Pontes
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Ad Wiebenga
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Vivian Ng
- US Department of Energy Joint Genome Institute, Walnut Creek, CA USA
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, Walnut Creek, CA USA
| | - Guifen He
- US Department of Energy Joint Genome Institute, Walnut Creek, CA USA
| | - Diane Bauer
- US Department of Energy Joint Genome Institute, Walnut Creek, CA USA
| | - Igor V. Grigoriev
- US Department of Energy Joint Genome Institute, Walnut Creek, CA USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA USA
| | - Ronald P. de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
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29
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Lubbers RJM, Liwanag AJ, Peng M, Dilokpimol A, Benoit-Gelber I, de Vries RP. Evolutionary adaptation of Aspergillus niger for increased ferulic acid tolerance. J Appl Microbiol 2019; 128:735-746. [PMID: 31674709 PMCID: PMC7027748 DOI: 10.1111/jam.14505] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 10/28/2019] [Accepted: 10/29/2019] [Indexed: 01/07/2023]
Abstract
AIMS To create an Aspergillus niger mutant with increased tolerance against ferulic acid using evolutionary adaptation. METHODS AND RESULTS Evolutionary adaptation of A. niger N402 was performed by consecutive growth on increasing concentrations of ferulic acid in the presence of 25 mmol l-1 d-fructose, starting from 0·5 mmol l-1 and ending with 5 mmol l-1 ferulic acid. The A. niger mutant obtained after six months, named Fa6, showed increased ferulic acid tolerance compared to the parent. In addition, Fa6 has increased ferulic acid consumption and a higher conversion rate, suggesting that the mutation affects aromatic metabolism of this species. Transcriptome analysis of the evolutionary mutant on ferulic acid revealed a distinct gene expression profile compared to the wild type. Further analysis of this mutant and the parent strain provided the first experimental confirmation that A. niger converts coniferyl alcohol to ferulic acid. CONCLUSIONS The evolutionary adaptive A. niger mutant Fa6 has beneficial mutations that increase the tolerance, conversion rate and uptake of ferulic acid. SIGNIFICANCE AND IMPACT OF THE STUDY This study demonstrates that evolutionary adaptation is a powerful tool to modify micro-organisms towards increased tolerance to harsh conditions, which is beneficial for various industrial applications.
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Affiliation(s)
- R J M Lubbers
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - A J Liwanag
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - M Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - A Dilokpimol
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - I Benoit-Gelber
- Centre for Structural and Functional Genomics, Concordia University, Montréal, Canada
| | - R P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
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dos Santos Gomes AC, Falkoski D, Battaglia E, Peng M, Nicolau de Almeida M, Coconi Linares N, Meijnen JP, Visser J, de Vries RP. Myceliophthora thermophila Xyr1 is predominantly involved in xylan degradation and xylose catabolism. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:220. [PMID: 31534479 PMCID: PMC6745793 DOI: 10.1186/s13068-019-1556-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 08/31/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND Myceliophthora thermophila is a thermophilic ascomycete fungus that is used as a producer of enzyme cocktails used in plant biomass saccharification. Further development of this species as an industrial enzyme factory requires a detailed understanding of its regulatory systems driving the production of plant biomass-degrading enzymes. In this study, we analyzed the function of MtXlr1, an ortholog of the (hemi-)cellulolytic regulator XlnR first identified in another industrially relevant fungus, Aspergillus niger. RESULTS The Mtxlr1 gene was deleted and the resulting strain was compared to the wild type using growth profiling and transcriptomics. The deletion strain was unable to grow on xylan and d-xylose, but showed only a small growth reduction on l-arabinose, and grew similar to the wild type on Avicel and cellulose. These results were supported by the transcriptome analyses which revealed reduction of genes encoding xylan-degrading enzymes, enzymes of the pentose catabolic pathway and putative pentose transporters. In contrast, no or minimal effects were observed for the expression of cellulolytic genes. CONCLUSIONS Myceliophthora thermophila MtXlr1 controls the expression of xylanolytic genes and genes involved in pentose transport and catabolism, but has no significant effects on the production of cellulases. It therefore resembles more the role of its ortholog in Neurospora crassa, rather than the broader role described for this regulator in A. niger and Trichoderma reesei. By revealing the range of genes controlled by MtXlr1, our results provide the basic knowledge for targeted strain improvement by overproducing or constitutively activating this regulator, to further improve the biotechnological value of M. thermophila.
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Affiliation(s)
- Ana Carolina dos Santos Gomes
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Daniel Falkoski
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
- Present Address: Novozymes Latin America, Professor Francisco Ribeiro Street 683, Araucária, PR 83707-660 Brazil
| | - Evy Battaglia
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Maira Nicolau de Almeida
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
- DuPont Industrial Biosciences, Archimedesweg 30, 2333 CN Leiden, The Netherlands
- Present Address: Federal University of São João del Rei, Praça Dom Helvécio, 74, São João del Rei, Minas Gerais Brazil
| | - Nancy Coconi Linares
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Jean-Paul Meijnen
- DuPont Industrial Biosciences, Archimedesweg 30, 2333 CN Leiden, The Netherlands
- Present Address: Dutch DNA Biotech BV, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Jaap Visser
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Ronald P. de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
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Gao L, Li S, Xu Y, Xia C, Xu J, Liu J, Qin Y, Song X, Liu G, Qu Y. Mutation of a Conserved Alanine Residue in Transcription Factor AraR Leads to Hyperproduction of α‐l‐Arabinofuranosidases inPenicillium oxalicum. Biotechnol J 2019; 14:e1800643. [DOI: 10.1002/biot.201800643] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 12/20/2018] [Accepted: 01/02/2019] [Indexed: 12/18/2022]
Affiliation(s)
- Liwei Gao
- State Key Laboratory of Microbial TechnologyShandong University27 Binhai Road 266237 Qingdao China
- State Key Laboratory of Bioreactor EngineeringEast China University of Science and TechnologyShanghai China
| | - Shiying Li
- State Key Laboratory of Microbial TechnologyShandong University27 Binhai Road 266237 Qingdao China
| | - Yanning Xu
- State Key Laboratory of Microbial TechnologyShandong University27 Binhai Road 266237 Qingdao China
| | - Chengqiang Xia
- State Key Laboratory of Microbial TechnologyShandong University27 Binhai Road 266237 Qingdao China
| | - Jiadi Xu
- State Key Laboratory of Microbial TechnologyShandong University27 Binhai Road 266237 Qingdao China
- National Glycoengineering Research CenterShandong UniversityQingdao China
| | - Jun Liu
- State Key Laboratory of Microbial TechnologyShandong University27 Binhai Road 266237 Qingdao China
| | - Yuqi Qin
- State Key Laboratory of Microbial TechnologyShandong University27 Binhai Road 266237 Qingdao China
- National Glycoengineering Research CenterShandong UniversityQingdao China
| | - Xin Song
- State Key Laboratory of Microbial TechnologyShandong University27 Binhai Road 266237 Qingdao China
| | - Guodong Liu
- State Key Laboratory of Microbial TechnologyShandong University27 Binhai Road 266237 Qingdao China
- State Key Laboratory of Bioreactor EngineeringEast China University of Science and TechnologyShanghai China
| | - Yinbo Qu
- State Key Laboratory of Microbial TechnologyShandong University27 Binhai Road 266237 Qingdao China
- National Glycoengineering Research CenterShandong UniversityQingdao China
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Mutations in AraR leading to constitutive expression of arabinolytic genes in Aspergillus niger under derepressing conditions [corrected]. Appl Microbiol Biotechnol 2019; 103:4125-4136. [PMID: 30963207 PMCID: PMC6486530 DOI: 10.1007/s00253-019-09777-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 03/08/2019] [Accepted: 03/12/2019] [Indexed: 12/20/2022]
Abstract
The AraR transcription factor of Aspergillus niger encodes a Zn(II)2Cys6 transcription factor required for the induction of genes encoding arabinolytic enzymes. One of the target genes of AraR is abfA, encoding an arabinofuranosidase. The expression of abfA as well as other L-arabinose-induced genes in A. niger requires the presence of L-arabinose or its derivative L-arabitol as an inducer to activate AraR-dependant gene expression. In this study, mutants were isolated that express L-arabinose-induced genes independently of the presence of an inducer under derepressing conditions. To obtain these mutants, a reporter strain was constructed in a ΔcreA background containing the L-arabinose-responsive promoter (PabfA) fused to the acetamidase (amdS) gene. Spores of the ΔcreA PabfA-amdS reporter strain were UV-mutagenized and mutants were obtained by their ability to grow on acetamide without the presence of inducer. From a total of 164 mutants, 15 mutants were identified to contain transacting mutations resulting in high arabinofuranosidase activity in the medium after growth under non-inducing conditions. Sequencing of the araR gene of the 15 constitutive mutants revealed that 14 mutants carried a mutation in AraR. Some mutations were found more than once and in total nine different point mutations were identified in AraR. The AraRN806I point mutation was reintroduced into a parental strain and confirmed that this point mutation leads to inducer-independent expression of AraR target genes. The inducer independent of L-arabinose-induced genes in the AraRN806I mutant was found to be sensitive to carbon catabolite repression, indicating that the CreA-mediated carbon catabolite repression is dominant over the AraRN806I mutant allele. These mutations in AraR provide new opportunities to improve arabinase production in industrial fungal strains.
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Developments and opportunities in fungal strain engineering for the production of novel enzymes and enzyme cocktails for plant biomass degradation. Biotechnol Adv 2019; 37:107361. [PMID: 30825514 DOI: 10.1016/j.biotechadv.2019.02.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 02/11/2019] [Accepted: 02/23/2019] [Indexed: 12/26/2022]
Abstract
Fungal strain engineering is commonly used in many areas of biotechnology, including the production of plant biomass degrading enzymes. Its aim varies from the production of specific enzymes to overall increased enzyme production levels and modification of the composition of the enzyme set that is produced by the fungus. Strain engineering involves a diverse range of methodologies, including classical mutagenesis, genetic engineering and genome editing. In this review, the main approaches for strain engineering of filamentous fungi in the field of plant biomass degradation will be discussed, including recent and not yet implemented methods, such as CRISPR/Cas9 genome editing and adaptive evolution.
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The presence of trace components significantly broadens the molecular response of Aspergillus niger to guar gum. N Biotechnol 2019; 51:57-66. [PMID: 30797054 DOI: 10.1016/j.nbt.2019.02.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 12/07/2018] [Accepted: 02/20/2019] [Indexed: 11/22/2022]
Abstract
Guar gum consists mainly of galactomannan and constitutes the endosperm of guar seeds that acts as a reserve polysaccharide for germination. Due to its molecular structure and physical properties, this biopolymer has been considered as one of the most important and widely used gums in industry. However, for many of these applications this (hemi-)cellulosic structure needs to be modified or (partially) depolymerized in order to customize and improve its physicochemical properties. In this study, transcriptome, exoproteome and enzyme activity analyses were employed to decipher the complete enzymatic arsenal for guar gum depolymerization by Aspergillus niger. This multi-omic analysis revealed a set of 46 genes encoding carbohydrate-active enzymes (CAZymes) responding to the presence of guar gum, including CAZymes not only with preferred activity towards galactomannan, but also towards (arabino-)xylan, cellulose, starch and pectin, likely due to trace components in guar gum. This demonstrates that the purity of substrates has a strong effect on the resulting enzyme mixture produced by A. niger and probably by other fungi as well, which has significant implications for the commercial production of fungal enzyme cocktails.
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Schmitz K, Protzko R, Zhang L, Benz JP. Spotlight on fungal pectin utilization-from phytopathogenicity to molecular recognition and industrial applications. Appl Microbiol Biotechnol 2019; 103:2507-2524. [PMID: 30694345 DOI: 10.1007/s00253-019-09622-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 01/03/2019] [Accepted: 01/04/2019] [Indexed: 11/29/2022]
Abstract
Pectin is a complex polysaccharide with D-galacturonic acid as its main component that predominantly accumulates in the middle lamella of the plant cell wall. Integrity and depolymerization of pectic structures have long been identified as relevant factors in fungal phytosymbiosis and phytopathogenicity in the context of tissue penetration and carbon source supply. While the pectic content of a plant cell wall can vary significantly, pectin was reported to account for up to 20-25% of the total dry weight in soft and non-woody tissues with non- or mildly lignified secondary cell walls, such as found in citrus peel, sugar beet pulp, and apple pomace. Due to their potential applications in various industrial sectors, pectic sugars from these and similar agricultural waste streams have been recognized as valuable targets for a diverse set of biotechnological fermentations.Recent advances in uncovering the molecular regulation mechanisms for pectinase expression in saprophytic fungi have led to a better understanding of fungal pectin sensing and utilization that could help to improve industrial, pectin-based fermentations. Related research in phytopathogenic fungi has furthermore added to our knowledge regarding the relevance of pectinases in plant cell wall penetration during onset of disease and is therefore highly relevant for agricultural sciences and the agricultural industry. This review therefore aims at summarizing (i) the role of pectinases in phytopathogenicity, (ii) the global regulation patterns for pectinase expression in saprophytic filamentous fungi as a highly specialized class of pectin degraders, and (iii) the current industrial applications in pectic sugar fermentations and transformations.
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Affiliation(s)
- Kevin Schmitz
- Holzforschung München, TUM School of Life Sciences Weihenstephan, Technische Universität München, Freising, Germany
| | - Ryan Protzko
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Lisha Zhang
- Department of Plant Biochemistry, Centre for Plant Molecular Biology, Eberhard Karls University Tübingen, Tübingen, Germany
| | - J Philipp Benz
- Holzforschung München, TUM School of Life Sciences Weihenstephan, Technische Universität München, Freising, Germany.
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Benocci T, Aguilar-Pontes MV, Kun RS, Lubbers RJM, Lail K, Wang M, Lipzen A, Ng V, Grigoriev IV, Seiboth B, Daly P, de Vries RP. Deletion of either the regulatory gene ara1 or metabolic gene xki1 in Trichoderma reesei leads to increased CAZyme gene expression on crude plant biomass. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:81. [PMID: 31007715 PMCID: PMC6454604 DOI: 10.1186/s13068-019-1422-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 04/03/2019] [Indexed: 05/17/2023]
Abstract
BACKGROUND Trichoderma reesei is one of the major producers of enzymes for the conversion of plant biomass to sustainable fuels and chemicals. Crude plant biomass can induce the production of CAZymes in T. reesei, but there is limited understanding of how the transcriptional response to crude plant biomass is regulated. In addition, it is unknown whether induction on untreated recalcitrant crude plant biomass (with a large diversity of inducers) can be sustained for longer. We investigated the transcriptomic response of T. reesei to the two industrial feedstocks, corn stover (CS) and soybean hulls (SBH), over time (4 h, 24 h and 48 h), and its regulatory basis using transcription factor deletion mutants (Δxyr1 and Δara1). We also investigated whether deletion of a xylulokinase gene (Δxki1) from the pentose catabolic pathway that converts potential inducers could lead to increased CAZyme gene expression. RESULTS By analyzing the transcriptomic responses using clustering as well as differential and cumulative expression of plant biomass degrading CAZymes, we found that corn stover induced a broader range and higher expression of CAZymes in T. reesei, while SBH induced more pectinolytic and mannanolytic transcripts. XYR1 was the major TF regulating CS utilization, likely due to the significant amount of d-xylose in this substrate. In contrast, ARA1 had a stronger effect on SBH utilization, which correlates with a higher abundance of l-arabinose in SBH that activates ARA1. Blocking pentose catabolism by deletion of xki1 led to higher expression of CAZyme encoding genes on both substrates at later time points. Surprisingly, this was also observed for Δara1 at later time points. Many of these genes were XYR1 regulated, suggesting that inducers for this regulator accumulated over time on both substrates. CONCLUSION Our data demonstrates the complexity of the regulatory system related to plant biomass degradation in T. reesei and the effect the feedstock composition has on this. Furthermore, this dataset provides leads to improve the efficiency of a T. reesei enzyme cocktail, such as by the choice of substrate or by deleting xki1 to obtain higher production of plant biomass degrading CAZymes.
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Affiliation(s)
- Tiziano Benocci
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Maria Victoria Aguilar-Pontes
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Roland Sándor Kun
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Ronnie J. M. Lubbers
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Kathleen Lail
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA 94598 USA
| | - Mei Wang
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA 94598 USA
| | - Anna Lipzen
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA 94598 USA
| | - Vivian Ng
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA 94598 USA
| | - Igor V. Grigoriev
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA 94598 USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA 94598 USA
| | - Bernhard Seiboth
- Research Area Biochemical Technology, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, 1060 Vienna, Austria
| | - Paul Daly
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Ronald P. de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
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l-Arabinose induces d-galactose catabolism via the Leloir pathway in Aspergillus nidulans. Fungal Genet Biol 2018; 123:53-59. [PMID: 30496805 DOI: 10.1016/j.fgb.2018.11.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 11/03/2018] [Accepted: 11/25/2018] [Indexed: 11/22/2022]
Abstract
l-Arabinose and d-galactose are the principal constituents of l-arabinogalactan, and also co-occur in other hemicelluloses and pectins. In this work we hypothesized that similar to the induction of relevant glycoside hydrolases by monomers liberated from these plant heteropolymers, their respective catabolisms in saprophytic and phytopathogenic fungi may respond to the presence of the other sugar to promote synergistic use of the complex growth substrate. We showed that these two sugars are indeed consumed simultaneously by Aspergillus nidulans, while l-arabinose is utilised faster in the presence than in the absence of d-galactose. Furthermore, the first two genes of the Leloir pathway for d-galactose catabolism - encoding d-galactose 1-epimerase and galactokinase - are induced more rapidly by l-arabinose than by d-galactose eventhough deletion mutants thereof grow as well as a wild type strain on the pentose. d-Galactose 1-epimerase is hyperinduced by l-arabinose, d-xylose and l-arabitol but not by xylitol. The results suggest that in A. nidulans, l-arabinose and d-xylose - both requiring NADPH for their catabolisation - actively promote the enzyme infrastructure necessary to convert β-d-galactopyranose via the Leloir pathway with its α-anomer specific enzymes, into β-d-glucose-6-phosphate (the starting substrate of the oxidative part of the pentose phosphate pathway) even in the absence of d-galactose.
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Alazi E, Ram AFJ. Modulating Transcriptional Regulation of Plant Biomass Degrading Enzyme Networks for Rational Design of Industrial Fungal Strains. Front Bioeng Biotechnol 2018; 6:133. [PMID: 30320082 PMCID: PMC6167437 DOI: 10.3389/fbioe.2018.00133] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 09/05/2018] [Indexed: 01/08/2023] Open
Abstract
Filamentous fungi are the most important microorganisms for the industrial production of plant polysaccharide degrading enzymes due to their unique ability to secrete these proteins efficiently. These carbohydrate active enzymes (CAZymes) are utilized industrially for the hydrolysis of plant biomass for the subsequent production of biofuels and high-value biochemicals. The expression of the genes encoding plant biomass degrading enzymes is tightly controlled. Naturally, large amounts of CAZymes are produced and secreted only in the presence of the plant polysaccharide they specifically act on. The signal to produce is conveyed via so-called inducer molecules which are di- or mono-saccharides (or derivatives thereof) released from the specific plant polysaccharides. The presence of the inducer results in the activation of a substrate-specific transcription factor (TF), which is required not only for the controlled expression of the genes encoding the CAZymes, but often also for the regulation of the expression of the genes encoding sugar transporters and catabolic pathway enzymes needed to utilize the released monosaccharide. Over the years, several substrate-specific TFs involved in the degradation of cellulose, hemicellulose, pectin, starch and inulin have been identified in several fungal species and systems biology approaches have made it possible to uncover the enzyme networks controlled by these TFs. The requirement for specific inducers for TF activation and subsequently the expression of particular enzyme networks determines the choice of feedstock to produce enzyme cocktails for industrial use. It also results in batch-to-batch variation in the composition and amounts of enzymes due to variations in sugar composition and polysaccharide decorations of the feedstock which hampers the use of cheap feedstocks for constant quality of enzyme cocktails. It is therefore of industrial interest to produce specific enzyme cocktails constitutively and independently of inducers. In this review, we focus on the methods to modulate TF activities for inducer-independent production of CAZymes and highlight various approaches that are used to construct strains displaying constitutive expression of plant biomass degrading enzyme networks. These approaches and combinations thereof are also used to construct strains displaying increased expression of CAZymes under inducing conditions, and make it possible to design strains in which different enzyme mixtures are simultaneously produced independently of the carbon source.
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Affiliation(s)
| | - Arthur F. J. Ram
- Molecular Microbiology and Biotechnology, Institute of Biology Leiden, Leiden University, Leiden, Netherlands
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Mäkelä M, DiFalco M, McDonnell E, Nguyen T, Wiebenga A, Hildén K, Peng M, Grigoriev I, Tsang A, de Vries R. Genomic and exoproteomic diversity in plant biomass degradation approaches among Aspergilli. Stud Mycol 2018; 91:79-99. [PMID: 30487660 PMCID: PMC6249967 DOI: 10.1016/j.simyco.2018.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
We classified the genes encoding carbohydrate-active enzymes (CAZymes) in 17 sequenced genomes representing 16 evolutionarily diverse Aspergillus species. We performed a phylogenetic analysis of the encoding enzymes, along with experimentally characterized CAZymes, to assign molecular function to the Aspergilli CAZyme families and subfamilies. Genome content analysis revealed that the numbers of CAZy genes per CAZy family related to plant biomass degradation follow closely the taxonomic distance between the species. On the other hand, growth analysis showed almost no correlation between the number of CAZyme genes and the efficiency in polysaccharide utilization. The exception is A. clavatus where a reduced number of pectinolytic enzymes can be correlated with poor growth on pectin. To gain detailed information on the enzymes used by Aspergilli to breakdown complex biomass, we conducted exoproteome analysis by mass spectrometry. These results showed that Aspergilli produce many different enzymes mixtures in the presence of sugar beet pulp and wheat bran. Despite the diverse enzyme mixtures produced, species of section Nigri, A. aculeatus, A. nidulans and A. terreus, produce mixtures of enzymes with activities that are capable of digesting all the major polysaccharides in the available substrates, suggesting that they are capable of degrading all the polysaccharides present simultaneously. For the other Aspergilli, typically the enzymes produced are targeted to a subset of polysaccharides present, suggesting that they can digest only a subset of polysaccharides at a given time.
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Affiliation(s)
- M.R. Mäkelä
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Viikinkaari 9, 00014, Helsinki, Finland
| | - M. DiFalco
- Centre for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke Street West, Montréal, Québec, H4B1R6, Canada
| | - E. McDonnell
- Centre for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke Street West, Montréal, Québec, H4B1R6, Canada
| | - T.T.M. Nguyen
- Centre for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke Street West, Montréal, Québec, H4B1R6, Canada
| | - A. Wiebenga
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT, Utrecht, the Netherlands
- Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - K. Hildén
- Department of Microbiology, Faculty of Agriculture and Forestry, University of Helsinki, Viikinkaari 9, 00014, Helsinki, Finland
| | - M. Peng
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT, Utrecht, the Netherlands
- Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - I.V. Grigoriev
- US Department of Energy Joint Genome Institute, 2800 Mitchell Drive, Walnut Creek, CA, 94598, USA
- Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, CA, 94598, USA
| | - A. Tsang
- Centre for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke Street West, Montréal, Québec, H4B1R6, Canada
| | - R.P. de Vries
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT, Utrecht, the Netherlands
- Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
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Comparison of the paralogous transcription factors AraR and XlnR in Aspergillus oryzae. Curr Genet 2018; 64:1245-1260. [PMID: 29654355 DOI: 10.1007/s00294-018-0837-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 04/08/2018] [Accepted: 04/11/2018] [Indexed: 10/17/2022]
Abstract
The paralogous transcription factors AraR and XlnR in Aspergillus regulate genes that are involved in degradation of cellulose and hemicellulose and catabolism of pentose. AraR and XlnR target the same genes for pentose catabolism but target different genes encoding enzymes for polysaccharide degradation. To uncover the relationship between these paralogous transcription factors, we examined their contribution to regulation of the PCP genes and compared their preferred recognition sequences. Both AraR and XlnR are involved in induction of all the pentose catabolic genes in A. oryzae except larA encoding L-arabinose reductase, which was regulated by AraR but not by XlnR. DNA-binding studies revealed that the recognition sequences of AraR and XlnR also differ only slightly; AraR prefers CGGDTAAW, while XlnR prefers CGGNTAAW. All the pentose catabolic genes possess at least one recognition site to which both AraR and XlnR can bind. Cooperative binding by the factors was not observed. Instead, they competed to bind to the shared sites. XlnR bound to the recognition sites mentioned above as a monomer, but bound to the sequence TTAGSCTAA on the xylanase promoters as a dimer. Consequently, AraR and XlnR have significantly similar, but not the same, DNA-binding properties. Such a slight difference in these paralogous transcription factors may lead to complex outputs in enzyme production depending on the concentrations of coexisting inducer molecules in the natural environment.
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Gong W, Dai L, Zhang H, Zhang L, Wang L. A Highly Efficient Xylan-Utilization System in Aspergillus niger An76: A Functional-Proteomics Study. Front Microbiol 2018; 9:430. [PMID: 29623069 PMCID: PMC5874446 DOI: 10.3389/fmicb.2018.00430] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 02/26/2018] [Indexed: 11/23/2022] Open
Abstract
Xylan constituted with β-1,4-D-xylose linked backbone and diverse substituted side-chains is the most abundant hemicellulose component of biomass, which can be completely and rapidly degraded into fermentable sugars by Aspergillus niger. This is of great value for obtaining renewable biofuels and biochemicals. To clarify the underlying mechanisms associated with highly efficient xylan degradation, assimilation, and metabolism by A. niger, we utilized functional proteomics to analyze the secreted proteins, sugar transporters, and intracellular proteins of A. niger An76 grown on xylan-based substrates. Results demonstrated that the complete xylanolytic enzyme system required for xylan degradation and composed of diverse isozymes was secreted in a sequential order. Xylan-backbone-degrading enzymes were preferentially induced by xylose or other soluble sugars, which efficiently produced large amounts of xylooligosaccharides (XOS) and xylose; however, XOS was more efficient than xylose in triggering the expression of the key transcription activator XlnR, resulting in higher xylanase activity and shortening xylanase-production time. Moreover, the substituted XOS was responsible for improving the abundance of side-chain-degrading enzymes, specific transporters, and key reductases and dehydrogenases in the pentose catabolic pathway. Our findings indicated that industries might be able to improve the species and concentrations of xylan-degrading enzymes and shorten fermentation time by adding abundant intermediate products of natural xylan (XOS) to cultures of filamentous fungi.
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Affiliation(s)
- Weili Gong
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, China
| | - Lin Dai
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, China
| | - Huaiqiang Zhang
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, China
| | - Lili Zhang
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, China
| | - Lushan Wang
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, China.,State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
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Adnan M, Zheng W, Islam W, Arif M, Abubakar YS, Wang Z, Lu G. Carbon Catabolite Repression in Filamentous Fungi. Int J Mol Sci 2017; 19:ijms19010048. [PMID: 29295552 PMCID: PMC5795998 DOI: 10.3390/ijms19010048] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2017] [Revised: 12/13/2017] [Accepted: 12/20/2017] [Indexed: 12/18/2022] Open
Abstract
Carbon Catabolite Repression (CCR) has fascinated scientists and researchers around the globe for the past few decades. This important mechanism allows preferential utilization of an energy-efficient and readily available carbon source over relatively less easily accessible carbon sources. This mechanism helps microorganisms to obtain maximum amount of glucose in order to keep pace with their metabolism. Microorganisms assimilate glucose and highly favorable sugars before switching to less-favored sources of carbon such as organic acids and alcohols. In CCR of filamentous fungi, CreA acts as a transcription factor, which is regulated to some extent by ubiquitination. CreD-HulA ubiquitination ligase complex helps in CreA ubiquitination, while CreB-CreC deubiquitination (DUB) complex removes ubiquitin from CreA, which causes its activation. CCR of fungi also involves some very crucial elements such as Hexokinases, cAMP, Protein Kinase (PKA), Ras proteins, G protein-coupled receptor (GPCR), Adenylate cyclase, RcoA and SnfA. Thorough study of molecular mechanism of CCR is important for understanding growth, conidiation, virulence and survival of filamentous fungi. This review is a comprehensive revision of the regulation of CCR in filamentous fungi as well as an updated summary of key regulators, regulation of different CCR-dependent mechanisms and its impact on various physical characteristics of filamentous fungi.
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Affiliation(s)
- Muhammad Adnan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Key Laboratory of Bio-Pesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Wenhui Zheng
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Key Laboratory of Bio-Pesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Waqar Islam
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Muhammad Arif
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Yakubu Saddeeq Abubakar
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Key Laboratory of Bio-Pesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Zonghua Wang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Key Laboratory of Bio-Pesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Guodong Lu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- Key Laboratory of Bio-Pesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
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Benocci T, Aguilar-Pontes MV, Kun RS, Seiboth B, de Vries RP, Daly P. ARA1 regulates not only l-arabinose but also d-galactose catabolism in Trichoderma reesei. FEBS Lett 2017; 592:60-70. [PMID: 29215697 DOI: 10.1002/1873-3468.12932] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 11/18/2017] [Accepted: 11/29/2017] [Indexed: 11/11/2022]
Abstract
Trichoderma reesei is used to produce saccharifying enzyme cocktails for biofuels. There is limited understanding of the transcription factors (TFs) that regulate genes involved in release and catabolism of l-arabinose and d-galactose, as the main TF XYR1 is only partially involved. Here, the T. reesei ortholog of ARA1 from Pyricularia oryzae that regulates l-arabinose releasing and catabolic genes was deleted and characterized by growth profiling and transcriptomics along with a xyr1 mutant and xyr1/ara1 double mutant. Our results show that in addition to the l-arabinose-related role, T. reesei ARA1 is essential for expression of d-galactose releasing and catabolic genes, while XYR1 is not involved in this process.
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Affiliation(s)
- Tiziano Benocci
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, The Netherlands
| | - Maria Victoria Aguilar-Pontes
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, The Netherlands
| | - Roland Sándor Kun
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, The Netherlands
| | - Bernhard Seiboth
- Research Area Biochemical Technology, Institute of Chemical, Environmental and Biological Engineering, TU Wien, Vienna, Austria
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, The Netherlands
| | - Paul Daly
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, The Netherlands
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44
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Gruben BS, Mäkelä MR, Kowalczyk JE, Zhou M, Benoit-Gelber I, De Vries RP. Expression-based clustering of CAZyme-encoding genes of Aspergillus niger. BMC Genomics 2017; 18:900. [PMID: 29169319 PMCID: PMC5701360 DOI: 10.1186/s12864-017-4164-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 10/05/2017] [Indexed: 11/29/2022] Open
Abstract
Background The Aspergillus niger genome contains a large repertoire of genes encoding carbohydrate active enzymes (CAZymes) that are targeted to plant polysaccharide degradation enabling A. niger to grow on a wide range of plant biomass substrates. Which genes need to be activated in certain environmental conditions depends on the composition of the available substrate. Previous studies have demonstrated the involvement of a number of transcriptional regulators in plant biomass degradation and have identified sets of target genes for each regulator. In this study, a broad transcriptional analysis was performed of the A. niger genes encoding (putative) plant polysaccharide degrading enzymes. Microarray data focusing on the initial response of A. niger to the presence of plant biomass related carbon sources were analyzed of a wild-type strain N402 that was grown on a large range of carbon sources and of the regulatory mutant strains ΔxlnR, ΔaraR, ΔamyR, ΔrhaR and ΔgalX that were grown on their specific inducing compounds. Results The cluster analysis of the expression data revealed several groups of co-regulated genes, which goes beyond the traditionally described co-regulated gene sets. Additional putative target genes of the selected regulators were identified, based on their expression profile. Notably, in several cases the expression profile puts questions on the function assignment of uncharacterized genes that was based on homology searches, highlighting the need for more extensive biochemical studies into the substrate specificity of enzymes encoded by these non-characterized genes. The data also revealed sets of genes that were upregulated in the regulatory mutants, suggesting interaction between the regulatory systems and a therefore even more complex overall regulatory network than has been reported so far. Conclusions Expression profiling on a large number of substrates provides better insight in the complex regulatory systems that drive the conversion of plant biomass by fungi. In addition, the data provides additional evidence in favor of and against the similarity-based functions assigned to uncharacterized genes. Electronic supplementary material The online version of this article (10.1186/s12864-017-4164-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Birgit S Gruben
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584, CT, Utrecht, The Netherlands.,Microbiology, Utrecht University, Padualaan 8, 3584, CH, Utrecht, The Netherlands
| | - Miia R Mäkelä
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584, CT, Utrecht, The Netherlands.,Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584, CT, Utrecht, The Netherlands.,Department of Food and Environmental Sciences, Division of Microbiology and Biotechnology, Viikki Biocenter 1, University of Helsinki, Helsinki, Finland
| | - Joanna E Kowalczyk
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584, CT, Utrecht, The Netherlands.,Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584, CT, Utrecht, The Netherlands
| | - Miaomiao Zhou
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584, CT, Utrecht, The Netherlands.,Current affiliation: ATGM, Avans University of Applied Sciences, Lovensdijkstraat 61-63, 4818, AJ, Breda, The Netherlands
| | - Isabelle Benoit-Gelber
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584, CT, Utrecht, The Netherlands.,Microbiology, Utrecht University, Padualaan 8, 3584, CH, Utrecht, The Netherlands.,Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584, CT, Utrecht, The Netherlands.,Current affiliation: Center for Structural and Functional Genomics, Concordia University, 7141 Sherbrooke St. W, Montreal, QC, Canada
| | - Ronald P De Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584, CT, Utrecht, The Netherlands. .,Microbiology, Utrecht University, Padualaan 8, 3584, CH, Utrecht, The Netherlands. .,Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584, CT, Utrecht, The Netherlands.
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Kowalczyk JE, Khosravi C, Purvine S, Dohnalkova A, Chrisler WB, Orr G, Robinson E, Zink E, Wiebenga A, Peng M, Battaglia E, Baker S, de Vries RP. High resolution visualization and exo-proteomics reveal the physiological role of XlnR and AraR in plant biomass colonization and degradation by Aspergillus niger. Environ Microbiol 2017; 19:4587-4598. [PMID: 29027734 DOI: 10.1111/1462-2920.13923] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 08/18/2017] [Accepted: 08/30/2017] [Indexed: 11/28/2022]
Abstract
In A. niger, two transcription factors, AraR and XlnR, regulate the production of enzymes involved in degradation of arabinoxylan and catabolism of the released l-arabinose and d-xylose. Deletion of both araR and xlnR in leads to reduced production of (hemi)cellulolytic enzymes and reduced growth on arabinan, arabinogalactan and xylan. In this study, we investigated the colonization and degradation of wheat bran by the A. niger reference strain CBS 137562 and araR/xlnR regulatory mutants using high-resolution microscopy and exo-proteomics. We discovered that wheat bran flakes have a 'rough' and 'smooth' surface with substantially different affinity towards fungal hyphae. While colonization of the rough side was possible for all strains, the xlnR mutants struggled to survive on the smooth side of the wheat bran particles after 20 and 40 h post inoculation. Impaired colonization ability of the smooth surface of wheat bran was linked to reduced potential of ΔxlnR to secrete arabinoxylan and cellulose-degrading enzymes and indicates that XlnR is the major regulator that drives colonization of wheat bran in A. niger.
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Affiliation(s)
- Joanna E Kowalczyk
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Claire Khosravi
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Samuel Purvine
- Department of Energy, Environmental Molecular Sciences Laboratory, Richland, WA, USA
| | - Alice Dohnalkova
- Department of Energy, Environmental Molecular Sciences Laboratory, Richland, WA, USA
| | - William B Chrisler
- Department of Energy, Environmental Molecular Sciences Laboratory, Richland, WA, USA
| | - Galya Orr
- Department of Energy, Environmental Molecular Sciences Laboratory, Richland, WA, USA
| | - Errol Robinson
- Department of Energy, Environmental Molecular Sciences Laboratory, Richland, WA, USA
| | - Erika Zink
- Department of Energy, Environmental Molecular Sciences Laboratory, Richland, WA, USA
| | - Ad Wiebenga
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Evy Battaglia
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
| | - Scott Baker
- Department of Energy, Environmental Molecular Sciences Laboratory, Richland, WA, USA
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, the Netherlands
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46
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Kowalczyk JE, Lubbers RJM, Peng M, Battaglia E, Visser J, de Vries RP. Combinatorial control of gene expression in Aspergillus niger grown on sugar beet pectin. Sci Rep 2017; 7:12356. [PMID: 28955038 PMCID: PMC5617896 DOI: 10.1038/s41598-017-12362-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 09/07/2017] [Indexed: 01/06/2023] Open
Abstract
Aspergillus niger produces an arsenal of extracellular enzymes that allow synergistic degradation of plant biomass found in its environment. Pectin is a heteropolymer abundantly present in the primary cell wall of plants. The complex structure of pectin requires multiple enzymes to act together. Production of pectinolytic enzymes in A. niger is highly regulated, which allows flexible and efficient capture of nutrients. So far, three transcriptional activators have been linked to regulation of pectin degradation in A. niger. The L-rhamnose-responsive regulator RhaR controls the production of enzymes that degrade rhamnogalacturonan-I. The L-arabinose-responsive regulator AraR controls the production of enzymes that decompose the arabinan and arabinogalactan side chains of rhamnogalacturonan-II. The D-galacturonic acid-responsive regulator GaaR controls the production of enzymes that act on the polygalacturonic acid backbone of pectin. This project aims to better understand how RhaR, AraR and GaaR co-regulate pectin degradation. For that reason, we constructed single, double and triple disruptant strains of these regulators and analyzed their growth phenotype and pectinolytic gene expression in A. niger grown on sugar beet pectin.
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Affiliation(s)
- Joanna E Kowalczyk
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Ronnie J M Lubbers
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Evy Battaglia
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Jaap Visser
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands.
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47
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Changes of Scots Pine Phyllosphere and Soil Fungal Communities during Outbreaks of Defoliating Insects. FORESTS 2017. [DOI: 10.3390/f8090316] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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48
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Borin GP, Sanchez CC, de Santana ES, Zanini GK, Dos Santos RAC, de Oliveira Pontes A, de Souza AT, Dal'Mas RMMTS, Riaño-Pachón DM, Goldman GH, Oliveira JVDC. Comparative transcriptome analysis reveals different strategies for degradation of steam-exploded sugarcane bagasse by Aspergillus niger and Trichoderma reesei. BMC Genomics 2017; 18:501. [PMID: 28666414 PMCID: PMC5493111 DOI: 10.1186/s12864-017-3857-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 06/09/2017] [Indexed: 12/12/2022] Open
Abstract
Background Second generation (2G) ethanol is produced by breaking down lignocellulosic biomass into fermentable sugars. In Brazil, sugarcane bagasse has been proposed as the lignocellulosic residue for this biofuel production. The enzymatic cocktails for the degradation of biomass-derived polysaccharides are mostly produced by fungi, such as Aspergillus niger and Trichoderma reesei. However, it is not yet fully understood how these microorganisms degrade plant biomass. In order to identify transcriptomic changes during steam-exploded bagasse (SEB) breakdown, we conducted a RNA-seq comparative transcriptome profiling of both fungi growing on SEB as carbon source. Results Particular attention was focused on CAZymes, sugar transporters, transcription factors (TFs) and other proteins related to lignocellulose degradation. Although genes coding for the main enzymes involved in biomass deconstruction were expressed by both fungal strains since the beginning of the growth in SEB, significant differences were found in their expression profiles. The expression of these enzymes is mainly regulated at the transcription level, and A. niger and T. reesei also showed differences in TFs content and in their expression. Several sugar transporters that were induced in both fungal strains could be new players on biomass degradation besides their role in sugar uptake. Interestingly, our findings revealed that in both strains several genes that code for proteins of unknown function and pro-oxidant, antioxidant, and detoxification enzymes were induced during growth in SEB as carbon source, but their specific roles on lignocellulose degradation remain to be elucidated. Conclusions This is the first report of a time-course experiment monitoring the degradation of pretreated bagasse by two important fungi using the RNA-seq technology. It was possible to identify a set of genes that might be applied in several biotechnology fields. The data suggest that these two microorganisms employ different strategies for biomass breakdown. This knowledge can be exploited for the rational design of enzymatic cocktails and 2G ethanol production improvement. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3857-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Gustavo Pagotto Borin
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo, Caixa Postal 6170, 13083-970, Brazil
| | - Camila Cristina Sanchez
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo, Caixa Postal 6170, 13083-970, Brazil
| | - Eliane Silva de Santana
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo, Caixa Postal 6170, 13083-970, Brazil
| | - Guilherme Keppe Zanini
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo, Caixa Postal 6170, 13083-970, Brazil
| | - Renato Augusto Corrêa Dos Santos
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo, Caixa Postal 6170, 13083-970, Brazil
| | - Angélica de Oliveira Pontes
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo, Caixa Postal 6170, 13083-970, Brazil
| | - Aline Tieppo de Souza
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo, Caixa Postal 6170, 13083-970, Brazil
| | - Roberta Maria Menegaldo Tavares Soares Dal'Mas
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo, Caixa Postal 6170, 13083-970, Brazil
| | - Diego Mauricio Riaño-Pachón
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo, Caixa Postal 6170, 13083-970, Brazil.,Current address: Laboratório de Biologia de Sistemas Regulatórios, Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes, 748 - Butantã - São Paulo - SP, São Paulo, CEP 05508-000, Brazil
| | - Gustavo Henrique Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av do Café S/N, Ribeirão Preto, CEP, São Paulo, 14040-903, Brazil
| | - Juliana Velasco de Castro Oliveira
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Campinas, São Paulo, Caixa Postal 6170, 13083-970, Brazil.
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Alazi E, Khosravi C, Homan TG, du Pré S, Arentshorst M, Di Falco M, Pham TTM, Peng M, Aguilar-Pontes MV, Visser J, Tsang A, de Vries RP, Ram AFJ. The pathway intermediate 2-keto-3-deoxy-L-galactonate mediates the induction of genes involved in D-galacturonic acid utilization in Aspergillus niger. FEBS Lett 2017; 591:1408-1418. [PMID: 28417461 PMCID: PMC5488244 DOI: 10.1002/1873-3468.12654] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 04/10/2017] [Indexed: 01/21/2023]
Abstract
In Aspergillus niger, the enzymes encoded by gaaA, gaaB, and gaaC catabolize d‐galacturonic acid (GA) consecutively into l‐galactonate, 2‐keto‐3‐deoxy‐l‐galactonate, pyruvate, and l‐glyceraldehyde, while GaaD converts l‐glyceraldehyde to glycerol. Deletion of gaaB or gaaC results in severely impaired growth on GA and accumulation of l‐galactonate and 2‐keto‐3‐deoxy‐l‐galactonate, respectively. Expression levels of GA‐responsive genes are specifically elevated in the ∆gaaC mutant on GA as compared to the reference strain and other GA catabolic pathway deletion mutants. This indicates that 2‐keto‐3‐deoxy‐l‐galactonate is the inducer of genes required for GA utilization.
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Affiliation(s)
- Ebru Alazi
- Molecular Microbiology and Biotechnology, Institute of Biology Leiden, Leiden University, The Netherlands
| | - Claire Khosravi
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Utrecht University, The Netherlands
| | - Tim G Homan
- Molecular Microbiology and Biotechnology, Institute of Biology Leiden, Leiden University, The Netherlands
| | - Saskia du Pré
- Molecular Microbiology and Biotechnology, Institute of Biology Leiden, Leiden University, The Netherlands
| | - Mark Arentshorst
- Molecular Microbiology and Biotechnology, Institute of Biology Leiden, Leiden University, The Netherlands
| | - Marcos Di Falco
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Canada
| | - Thi T M Pham
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Canada
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Utrecht University, The Netherlands
| | | | - Jaap Visser
- Molecular Microbiology and Biotechnology, Institute of Biology Leiden, Leiden University, The Netherlands.,Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Utrecht University, The Netherlands
| | - Adrian Tsang
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Canada
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute, Utrecht University, The Netherlands
| | - Arthur F J Ram
- Molecular Microbiology and Biotechnology, Institute of Biology Leiden, Leiden University, The Netherlands
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50
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Benocci T, Aguilar-Pontes MV, Zhou M, Seiboth B, de Vries RP. Regulators of plant biomass degradation in ascomycetous fungi. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:152. [PMID: 28616076 PMCID: PMC5468973 DOI: 10.1186/s13068-017-0841-x] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 06/06/2017] [Indexed: 05/05/2023]
Abstract
Fungi play a major role in the global carbon cycle because of their ability to utilize plant biomass (polysaccharides, proteins, and lignin) as carbon source. Due to the complexity and heterogenic composition of plant biomass, fungi need to produce a broad range of degrading enzymes, matching the composition of (part of) the prevalent substrate. This process is dependent on a network of regulators that not only control the extracellular enzymes that degrade the biomass, but also the metabolic pathways needed to metabolize the resulting monomers. This review will summarize the current knowledge on regulation of plant biomass utilization in fungi and compare the differences between fungal species, focusing in particular on the presence or absence of the regulators involved in this process.
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Affiliation(s)
- Tiziano Benocci
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Maria Victoria Aguilar-Pontes
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Miaomiao Zhou
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Bernhard Seiboth
- Research Area Biochemical Technology, Institute of Chemical and Biological Engineering, TU Wien, 1060 Vienna, Austria
| | - Ronald P. de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
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