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Jiang W, Chen J, Duan X, Li Y, Tao Z. Comparative Transcriptome Profiling Reveals Two WRKY Transcription Factors Positively Regulating Polysaccharide Biosynthesis in Polygonatum cyrtonema. Int J Mol Sci 2023; 24:12943. [PMID: 37629123 PMCID: PMC10454705 DOI: 10.3390/ijms241612943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 08/11/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
Polygonatum cyrtonema (P. cyrtonema) is a valuable rhizome-propagating traditional Chinese medical herb. Polysaccharides (PCPs) are the major bioactive constituents in P. cyrtonema. However, the molecular basis of PCP biosynthesis in P. cyrtonema remains unknown. In this study, we measured the PCP contents of 11 wild P. cyrtonema germplasms. The results showed that PCP content was the highest in Lishui Qingyuan (LSQY, 11.84%) and the lowest in Hangzhou Lin'an (HZLA, 7.18%). We next analyzed the transcriptome profiles of LSQY and HZLA. Through a qRT-PCR analysis of five differential expression genes from the PCP biosynthesis pathway, phosphomannomutase, UDP-glucose 4-epimerase (galE), and GDP-mannose 4,6-dehydratase were determined as the key enzymes. A protein of a key gene, galE1, was localized in the chloroplast. The PCP content in the transiently overexpressed galE1 tobacco leaves was higher than in the wild type. Moreover, luciferase and Y1H assays indicated that PcWRKY31 and PcWRKY34 could activate galE1 by binding to its promoter. Our research uncovers the novel regulatory mechanism of PCP biosynthesis in P. cyrtonema and is critical to molecular-assisted breeding.
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Affiliation(s)
- Wu Jiang
- Zhejiang Institute of Subtropical Crops, Zhejiang Academy of Agricultural Sciences, Wenzhou 325005, China; (W.J.); (J.C.); (X.D.)
- Zhejiang Provincial Key Laboratory of Resources Protection and Innovation of Traditional Chinese Medicine, Zhejiang A&F University, Hangzhou 311300, China;
| | - Jiadong Chen
- Zhejiang Institute of Subtropical Crops, Zhejiang Academy of Agricultural Sciences, Wenzhou 325005, China; (W.J.); (J.C.); (X.D.)
| | - Xiaojing Duan
- Zhejiang Institute of Subtropical Crops, Zhejiang Academy of Agricultural Sciences, Wenzhou 325005, China; (W.J.); (J.C.); (X.D.)
| | - Yaping Li
- Zhejiang Provincial Key Laboratory of Resources Protection and Innovation of Traditional Chinese Medicine, Zhejiang A&F University, Hangzhou 311300, China;
| | - Zhengming Tao
- Zhejiang Institute of Subtropical Crops, Zhejiang Academy of Agricultural Sciences, Wenzhou 325005, China; (W.J.); (J.C.); (X.D.)
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Gonçalves AL, Cunha PM, da Silva Lima A, Dos Santos JC, Segato F. Production of recombinant lytic polysaccharide monooxygenases and evaluation effect of its addition into Aspergillus fumigatus var. niveus cocktail for sugarcane bagasse saccharification. BIOCHIMICA ET BIOPHYSICA ACTA. PROTEINS AND PROTEOMICS 2023; 1871:140919. [PMID: 37164048 DOI: 10.1016/j.bbapap.2023.140919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/01/2023] [Accepted: 05/03/2023] [Indexed: 05/12/2023]
Abstract
Lignocellulosic biomass is a promising alternative for producing biofuels, despite its recalcitrant nature. There are microorganisms in nature capable of efficiently degrade biomass, such as the filamentous fungi. Among them, Aspergillus fumigatus var. niveus (AFUMN) has a wide variety of carbohydrate-active enzymes (CAZymes), especially hydrolases, but a low number of oxidative enzymes in its genome. To confirm the enzymatic profile of this fungus, this study analyzed the secretome of AFUMN cultured in sugarcane bagasse as the sole carbon source. As expected, the secretome showed a predominance of hydrolytic enzymes compared to oxidative activity. However, it is known that hydrolytic enzymes act in synergy with oxidative proteins to efficiently degrade cellulose polymer, such as the Lytic Polysaccharide Monooxygenases (LPMOs). Thus, three LPMOs from the fungus Thermothelomyces thermophilus (TtLPMO9D, TtLPMO9H, and TtLPMO9O) were selected, heterologous expressed in Aspergillus nidulans, purified, and used to supplement the AFUMN secretome to evaluate their effect on the saccharification of sugarcane bagasse. The saccharification assay was carried out using different concentrations of AFUMN secretome supplemented with recombinant T. thermophilus LPMOs, as well as ascorbic acid as reducing agent for oxidative enzymes. Through a statistic design created by Design-Expert software, we were able to analyze a possible cooperative effect between these components. The results indicated that, in general, the addition of TtLPMO9D and ascorbic acid did not favor the conversion process in this study, while TtLPMO9O had a highly significant cooperative effect in bagasse saccharification compared to the control using only AFUMN secretome.
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Affiliation(s)
- Aline Larissa Gonçalves
- Department of Biotechnology, Lorena School of Engineering, University of São Paulo, Lorena, SP, Brazil
| | - Paula Macedo Cunha
- Department of Biotechnology, Lorena School of Engineering, University of São Paulo, Lorena, SP, Brazil
| | - Awana da Silva Lima
- Department of Biotechnology, Lorena School of Engineering, University of São Paulo, Lorena, SP, Brazil
| | - Júlio César Dos Santos
- Department of Biotechnology, Lorena School of Engineering, University of São Paulo, Lorena, SP, Brazil
| | - Fernando Segato
- Department of Biotechnology, Lorena School of Engineering, University of São Paulo, Lorena, SP, Brazil.
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Shen L, Yan A, Wang Y, Wang Y, Liu H, Zhong Y. Tailoring the expression of Xyr1 leads to efficient production of lignocellulolytic enzymes in Trichoderma reesei for improved saccharification of corncob residues. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:142. [PMID: 36528622 PMCID: PMC9759857 DOI: 10.1186/s13068-022-02240-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 12/08/2022] [Indexed: 12/23/2022]
Abstract
BACKGROUND The filamentous fungus Trichoderma reesei is extensively used for the industrial-scale cellulase production. It has been well known that the transcription factor Xyr1 plays an important role in the regulatory network controlling cellulase gene expression. However, the role of Xyr1 in the regulation of cellulase expression has not been comprehensively elucidated, which hinders further improvement of lignocellulolytic enzyme production. RESULTS Here, the expression dosage of xyr1 was tailored in T. reesei by differentially overexpressing the xyr1 gene under the control of three strong promoters (Pegl2, Pcbh1, and Pcdna1), and the transcript abundance of xyr1 was elevated 5.8-, 12.6-, and 47.2-fold, respectively. We found expression of cellulase genes was significantly increased in the Pegl2-driven xyr1 overexpression strain QE2X, whereas relatively low in the Pcbh1- and Pcdna1-driven overexpression strains. We also found that the Pegl2-driven overexpression of xyr1 caused a more significant opening of chromatin in the core promoter region of the prominent cellulase genes. Furthermore, the cellulase activity showed a 3.2-fold increase in the strain QE2X, while insignificant improvement in the Pcbh1- and Pcdna1-driven strains. Finally, the saccharification efficiency toward acid-pretreated corncob residues containing high-content lignin by the crude enzyme from QE2X was increased by 57.2% compared to that from the parental strain. Moreover, LC-MS/MS and RT-qPCR analysis revealed that expression of accessory proteins (Cip1, Cip2, Swo1, and LPMOs) was greatly improved in QE2X, which partly explained the promoting effect of the Pegl2-driven overexpression on enzymatic hydrolysis of lignocellulose biomass. CONCLUSIONS Our results underpin that the precise tailoring expression of xyr1 is essential for highly efficient cellulase synthesis, which provide new insights into the role of Xyr1 in regulating cellulase expression in T. reesei. Moreover, these results also provides a prospective strategy for strain improvement to enhance the lignocellulolytic enzyme production for use in biorefinery applications.
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Affiliation(s)
- Linjing Shen
- grid.27255.370000 0004 1761 1174State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237 People’s Republic of China
| | - Aiqin Yan
- grid.27255.370000 0004 1761 1174State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237 People’s Republic of China
| | - Yifan Wang
- grid.27255.370000 0004 1761 1174State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237 People’s Republic of China
| | - Yubo Wang
- grid.27255.370000 0004 1761 1174State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237 People’s Republic of China
| | - Hong Liu
- grid.27255.370000 0004 1761 1174State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237 People’s Republic of China
| | - Yaohua Zhong
- grid.27255.370000 0004 1761 1174State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237 People’s Republic of China
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Lenz AR, Balbinot E, de Abreu FP, de Oliveira NS, Fontana RC, de Avila E Silva S, Park MS, Lim YW, Houbraken J, Camassola M, Dillon AJP. Taxonomy, comparative genomics and evolutionary insights of Penicillium ucsense: a novel species in series Oxalica. Antonie Van Leeuwenhoek 2022; 115:1009-1029. [PMID: 35678932 DOI: 10.1007/s10482-022-01746-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 05/03/2022] [Indexed: 10/18/2022]
Abstract
The genomes of two Penicillium strains were sequenced and studied in this study: strain 2HH was isolated from the digestive tract of Anobium punctatum beetle larva in 1979 and the cellulase hypersecretory strain S1M29, derived from strain 2HH by a long-term mutagenesis process. With these data, the strains were reclassified and insight is obtained on molecular features related to cellulase hyperproduction and the albino phenotype of the mutant. Both strains were previously identified as Penicillium echinulatum and this investigation indicated that these should be reclassified. Phylogenetic and phenotype data showed that these strains represent a new Penicillium species in series Oxalica, for which the name Penicillium ucsense is proposed here. Six additional strains (SFC101850, SFCP10873, SFCP10886, SFCP10931, SFCP10932 and SFCP10933) collected from the marine environment in the Republic of Korea were also classified as this species, indicating a worldwide distribution of this new taxon. Compared to the closely related strain Penicillium oxalicum 114-2, the composition of cell wall-associated proteins of P. ucsense 2HH shows five fewer chitinases, considerable differences in the number of proteins related to β-D-glucan metabolism. The genomic comparison of 2HH and S1M29 highlighted single amino-acid substitutions in two major proteins (BGL2 and FlbA) that can be associated with the hyperproduction of cellulases. The study of melanin pathways shows that the S1M29 albino phenotype resulted from a single amino-acid substitution in the enzyme ALB1, a precursor of the 1,8-dihydroxynaphthalene (DHN)-melanin biosynthesis. Our study provides important knowledge towards understanding species distribution, molecular mechanisms, melanin production and cell wall biosynthesis of this new Penicillium species.
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Affiliation(s)
- Alexandre Rafael Lenz
- Bioinformatics and Computational Biology Laboratory, Institute of Biotechnology, University of Caxias Do Sul, Francisco Getúlio Vargas Street 1130, Caxias do Sul, RS, 95070-560, Brazil. .,Bahia State University, Silveira Martins Street 2555, Salvador, BA, 41150-000, Brazil.
| | - Eduardo Balbinot
- Bioinformatics and Computational Biology Laboratory, Institute of Biotechnology, University of Caxias Do Sul, Francisco Getúlio Vargas Street 1130, Caxias do Sul, RS, 95070-560, Brazil
| | - Fernanda Pessi de Abreu
- Bioinformatics and Computational Biology Laboratory, Institute of Biotechnology, University of Caxias Do Sul, Francisco Getúlio Vargas Street 1130, Caxias do Sul, RS, 95070-560, Brazil
| | - Nikael Souza de Oliveira
- Bioinformatics and Computational Biology Laboratory, Institute of Biotechnology, University of Caxias Do Sul, Francisco Getúlio Vargas Street 1130, Caxias do Sul, RS, 95070-560, Brazil
| | - Roselei Claudete Fontana
- Laboratory of Enzymes and Biomass, Institute of Biotechnology, University of Caxias Do Sul, Francisco Getúlio Vargas Street 1130, Caxias do Sul, RS, 95070-560, Brazil
| | - Scheila de Avila E Silva
- Bioinformatics and Computational Biology Laboratory, Institute of Biotechnology, University of Caxias Do Sul, Francisco Getúlio Vargas Street 1130, Caxias do Sul, RS, 95070-560, Brazil
| | - Myung Soo Park
- School of Biological Sciences and Institution of Microbiology, Seoul National University, Seoul, 08826, South Korea
| | - Young Woon Lim
- School of Biological Sciences and Institution of Microbiology, Seoul National University, Seoul, 08826, South Korea
| | - Jos Houbraken
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Marli Camassola
- Laboratory of Enzymes and Biomass, Institute of Biotechnology, University of Caxias Do Sul, Francisco Getúlio Vargas Street 1130, Caxias do Sul, RS, 95070-560, Brazil
| | - Aldo José Pinheiro Dillon
- Laboratory of Enzymes and Biomass, Institute of Biotechnology, University of Caxias Do Sul, Francisco Getúlio Vargas Street 1130, Caxias do Sul, RS, 95070-560, Brazil
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Analysis of carbohydrate-active enzymes and sugar transporters in Penicillium echinulatum: A genome-wide comparative study of the fungal lignocellulolytic system. Gene 2022; 822:146345. [PMID: 35189252 DOI: 10.1016/j.gene.2022.146345] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 02/09/2022] [Accepted: 02/15/2022] [Indexed: 02/06/2023]
Abstract
Penicillium echinulatum 2HH is an ascomycete well known for its production of cellulolytic enzymes. Understanding lignocellulolytic and sugar uptake systems is essential to obtain efficient fungi strains for the production of bioethanol. In this study we performed a genome-wide functional annotation of carbohydrate-active enzymes and sugar transporters involved in the lignocellulolytic system of P. echinulatum 2HH and S1M29 strains (wildtype and mutant, respectively) and eleven related fungi. Additionally, signal peptide and orthology prediction were carried out. We encountered a diverse assortment of cellulolytic enzymes in P. echinulatum, especially in terms of β-glucosidases and endoglucanases. Other enzymes required for the breakdown of cellulosic biomass were also found, including cellobiohydrolases, lytic cellulose monooxygenases and cellobiose dehydrogenases. The S1M29 mutant, which is known to produce an increased cellulase activity, and the 2HH wild type strain of P. echinulatum did not show significant differences between their enzymatic repertoire. Nevertheless, we unveiled an amino acid substitution for a predicted intracellular β-glucosidase of the mutant, which might contribute to hyperexpression of cellulases through a cellodextrin induction pathway. Most of the P. echinulatum enzymes presented orthologs in P. oxalicum 114-2, supporting the presence of highly similar cellulolytic mechanisms and a close phylogenetic relationship between these fungi. A phylogenetic analysis of intracellular β-glucosidases and sugar transporters allowed us to identify several proteins potentially involved in the accumulation of intracellular cellodextrins. These may prove valuable targets in the genetic engineering of P. echinulatum focused on industrial cellulases production. Our study marks an important step in characterizing and understanding the molecular mechanisms employed by P. echinulatum in the enzymatic hydrolysis of lignocellulosic biomass.
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Corrêa TLR, Román EKB, da Silva Cassoli J, dos Santos LV, Pereira GAG. Secretome analysis of Trichoderma reesei RUT-C30 and Penicillium oxalicum reveals their synergic potential to deconstruct sugarcane and energy cane biomasses. Microbiol Res 2022; 260:127017. [DOI: 10.1016/j.micres.2022.127017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 02/18/2022] [Accepted: 03/29/2022] [Indexed: 11/28/2022]
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Endo-xylanases from Cohnella sp. AR92 aimed at xylan and arabinoxylan conversion into value-added products. Appl Microbiol Biotechnol 2021; 105:6759-6778. [PMID: 34458936 DOI: 10.1007/s00253-021-11495-5] [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: 02/24/2021] [Revised: 06/29/2021] [Accepted: 08/03/2021] [Indexed: 10/20/2022]
Abstract
The genus Cohnella belongs to a group of Gram-positive endospore-forming bacteria within the Paenibacillaceae family. Although most species were described as xylanolytic bacteria, the literature still lacks some key information regarding their repertoire of xylan-degrading enzymes. The whole genome sequence of an isolated xylan-degrading bacterium Cohnella sp. strain AR92 was found to contain five genes encoding putative endo-1,4-β-xylanases, of which four were cloned, expressed, and characterized to better understand the contribution of the individual endo-xylanases to the overall xylanolytic properties of strain AR92. Three of the enzymes, CoXyn10A, CoXyn10C, and CoXyn11A, were shown to be effective at hydrolyzing xylans-derived from agro-industrial, producing oligosaccharides with substrate conversion values of 32.5%, 24.7%, and 10.6%, respectively, using sugarcane bagasse glucuronoarabinoxylan and of 29.9%, 19.1%, and 8.0%, respectively, using wheat bran-derived arabinoxylan. The main reaction products from GH10 enzymes were xylobiose and xylotriose, whereas CoXyn11A produced mostly xylooligosaccharides (XOS) with 2 to 5 units of xylose, often substituted, resulting in potentially prebiotic arabinoxylooligosaccharides (AXOS). The endo-xylanases assay displayed operational features (temperature optima from 49.9 to 50.4 °C and pH optima from 6.01 to 6.31) fitting simultaneous xylan utilization. Homology modeling confirmed the typical folds of the GH10 and GH11 enzymes, substrate docking studies allowed the prediction of subsites (- 2 to + 1 in GH10 and - 3 to + 1 in GH11) and identification of residues involved in ligand interactions, supporting the experimental data. Overall, the Cohnella sp. AR92 endo-xylanases presented significant potential for enzymatic conversion of agro-industrial by-products into high-value products.Key points• Cohnella sp. AR92 genome encoded five potential endo-xylanases.• Cohnella sp. AR92 enzymes produced xylooligosaccharides from xylan, with high yields.• GH10 enzymes from Cohnella sp. AR92 are responsible for the production of X2 and X3 oligosaccharides.• GH11 from Cohnella sp. AR92 contributes to the overall xylan degradation by producing substituted oligosaccharides.
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Ogunyewo OA, Upadhyay P, Rajacharya GH, Okereke OE, Faas L, Gómez LD, McQueen-Mason SJ, Yazdani SS. Accessory enzymes of hypercellulolytic Penicillium funiculosum facilitate complete saccharification of sugarcane bagasse. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:171. [PMID: 34446097 PMCID: PMC8394629 DOI: 10.1186/s13068-021-02020-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 08/15/2021] [Indexed: 05/26/2023]
Abstract
BACKGROUND Sugarcane bagasse (SCB) is an abundant feedstock for second-generation bioethanol production. This complex biomass requires an array of carbohydrate active enzymes (CAZymes), mostly from filamentous fungi, for its deconstruction to monomeric sugars for the production of value-added fuels and chemicals. In this study, we evaluated the repertoire of proteins in the secretome of a catabolite repressor-deficient strain of Penicillium funiculosum, PfMig188, in response to SCB induction and examined their role in the saccharification of SCB. RESULTS A systematic approach was developed for the cultivation of the fungus with the aim of producing and understanding arrays of enzymes tailored for saccharification of SCB. To achieve this, the fungus was grown in media supplemented with different concentrations of pretreated SCB (0-45 g/L). The profile of secreted proteins was characterized by enzyme activity assays and liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 280 proteins were identified in the secretome of PfMig188, 46% of them being clearly identified as CAZymes. Modulation of the cultivation media with SCB up to 15 g/L led to sequential enhancement in the secretion of hemicellulases and cell wall-modifying enzymes, including endo-β-1,3(4)-glucanase (GH16), endo-α-1,3-glucanase (GH71), xylanase (GH30), β-xylosidase (GH5), β-1,3-galactosidase (GH43) and cutinase (CE5). There was ~ 122% and 60% increases in β-xylosidase and cutinase activities, respectively. There was also a 36% increase in activities towards mixed-linked glucans. Induction of these enzymes in the secretome improved the saccharification performance to 98% (~ 20% increase over control), suggesting their synergy with core cellulases in accessing the recalcitrant region of SCB. CONCLUSION Our findings provide an insight into the enzyme system of PfMig188 for degradation of complex biomass such as SCB and highlight the importance of adding SCB to the culture medium to optimize the secretion of enzymes specific for the saccharification of sugarcane bagasse.
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Affiliation(s)
- Olusola A Ogunyewo
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Pooja Upadhyay
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Girish H Rajacharya
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Omoaruemike E Okereke
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
- Biotechnology Advanced Research Centre, Sheda Science and Technology Complex (SHESTCO), Abuja, Nigeria
| | - Laura Faas
- Department of Biology, Centre for Novel Agricultural Products, CNAP, University of York, York, YO10 5DD, UK
| | - Leonardo D Gómez
- Department of Biology, Centre for Novel Agricultural Products, CNAP, University of York, York, YO10 5DD, UK
| | - Simon J McQueen-Mason
- Department of Biology, Centre for Novel Agricultural Products, CNAP, University of York, York, YO10 5DD, UK
| | - Syed Shams Yazdani
- Microbial Engineering Group, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India.
- DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India.
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Sethupathy S, Morales GM, Li Y, Wang Y, Jiang J, Sun J, Zhu D. Harnessing microbial wealth for lignocellulose biomass valorization through secretomics: a review. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:154. [PMID: 34225772 PMCID: PMC8256616 DOI: 10.1186/s13068-021-02006-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 06/26/2021] [Indexed: 05/10/2023]
Abstract
The recalcitrance of lignocellulosic biomass is a major constraint to its high-value use at industrial scale. In nature, microbes play a crucial role in biomass degradation, nutrient recycling and ecosystem functioning. Therefore, the use of microbes is an attractive way to transform biomass to produce clean energy and high-value compounds. The microbial degradation of lignocelluloses is a complex process which is dependent upon multiple secreted enzymes and their synergistic activities. The availability of the cutting edge proteomics and highly sensitive mass spectrometry tools make possible for researchers to probe the secretome of microbes and microbial consortia grown on different lignocelluloses for the identification of hydrolytic enzymes of industrial interest and their substrate-dependent expression. This review summarizes the role of secretomics in identifying enzymes involved in lignocelluloses deconstruction, the development of enzyme cocktails and the construction of synthetic microbial consortia for biomass valorization, providing our perspectives to address the current challenges.
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Affiliation(s)
- Sivasamy Sethupathy
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Gabriel Murillo Morales
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Yixuan Li
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Yongli Wang
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Jianxiong Jiang
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Jianzhong Sun
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Daochen Zhu
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China.
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Sun Y, Qian Y, Zhang J, Wang Y, Li X, Zhang W, Wang L, Liu H, Zhong Y. Extracellular protease production regulated by nitrogen and carbon sources in Trichoderma reesei. J Basic Microbiol 2021; 61:122-132. [PMID: 33393718 DOI: 10.1002/jobm.202000566] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 11/25/2020] [Accepted: 12/18/2020] [Indexed: 11/07/2022]
Abstract
The filamentous fungus Trichoderma reesei is an important producer of industrial enzymes, and possesses abundant extracellular protease genes based on the genome sequence data. However, the production of extracellular proteases remains poorly understood. Here, protease production was extensively investigated on different carbon (glucose and lactose) and nitrogen sources ((NH4 )2 SO4 , NaNO3 , peptone, and corn steep liquor). It was found that protease production was dominantly regulated by nitrogen sources. Organic nitrogen sources were beneficial for protease production, while the preferred nitrogen source (NH4 )2 SO4 inhibited the expression of proteases. As for carbon sources, lactose was a more effective inducer than glucose for protease production. The protease activity was further examined by protease inhibitors, which suggested that protease activity was predominantly inhibited by phenylmethanesulfonyl fluoride (PMSF) and slightly suppressed by ethylenediaminetetraacetic acid (EDTA). Moreover, proteomic analysis revealed a total of 29 extracellular proteases, including 13 serine proteases, 6 aspartic proteases, and 10 metalloproteases. In addition, seven proteases were found to be present among all conditions. These results showed the regulatory profile of extracellular protease production in Trichoderma reesei grown on various carbon and nitrogen sources, which will facilitate the development of T. reesei to be an effective workhorse for enzyme or high-value protein production in industry.
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Affiliation(s)
- Yu Sun
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, P.R. China
| | - Yuanchao Qian
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, P.R. China
| | - Jiaxin Zhang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, P.R. China
| | - Yifan Wang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, P.R. China
| | - Xihai Li
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, P.R. China
| | - Weican Zhang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, P.R. China
| | - Lushan Wang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, P.R. China
| | - Hong Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, P.R. China
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, P.R. China
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11
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Zandonadi FS, Ferreira SP, Alexandrino AV, Carnielli CM, Artier J, Barcelos MP, Nicolela NCS, Prieto EL, Goto LS, Belasque J, Novo-Mansur MTM. Periplasm-enriched fractions from Xanthomonas citri subsp. citri type A and X. fuscans subsp. aurantifolii type B present distinct proteomic profiles under in vitro pathogenicity induction. PLoS One 2020; 15:e0243867. [PMID: 33338036 PMCID: PMC7748154 DOI: 10.1371/journal.pone.0243867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 11/29/2020] [Indexed: 12/24/2022] Open
Abstract
The causative agent of Asiatic citrus canker, the Gram-negative bacterium Xanthomonas citri subsp. citri (XAC), produces more severe symptoms and attacks a larger number of citric hosts than Xanthomonas fuscans subsp. aurantifolii XauB and XauC, the causative agents of cancrosis, a milder form of the disease. Here we report a comparative proteomic analysis of periplasmic-enriched fractions of XAC and XauB in XAM-M, a pathogenicity- inducing culture medium, for identification of differential proteins. Proteins were resolved by two-dimensional electrophoresis combined with liquid chromatography-mass spectrometry. Among the 12 proteins identified from the 4 unique spots from XAC in XAM-M (p<0.05) were phosphoglucomutase (PGM), enolase, xylose isomerase (XI), transglycosylase, NAD(P)H-dependent glycerol 3-phosphate dehydrogenase, succinyl-CoA synthetase β subunit, 6-phosphogluconate dehydrogenase, and conserved hypothetical proteins XAC0901 and XAC0223; most of them were not detected as differential for XAC when both bacteria were grown in NB medium, a pathogenicity non-inducing medium. XauB showed a very different profile from XAC in XAM-M, presenting 29 unique spots containing proteins related to a great diversity of metabolic pathways. Preponderant expression of PGM and XI in XAC was validated by Western Blot analysis in the periplasmic-enriched fractions of both bacteria. This work shows remarkable differences between the periplasmic-enriched proteomes of XAC and XauB, bacteria that cause symptoms with distinct degrees of severity during citrus infection. The results suggest that some proteins identified in XAC can have an important role in XAC pathogenicity.
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Affiliation(s)
- Flávia S. Zandonadi
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCar, São Carlos, São Paulo, Brazil
| | - Sílvia P. Ferreira
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCar, São Carlos, São Paulo, Brazil
| | - André V. Alexandrino
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCar, São Carlos, São Paulo, Brazil
| | - Carolina M. Carnielli
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCar, São Carlos, São Paulo, Brazil
| | - Juliana Artier
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCar, São Carlos, São Paulo, Brazil
| | - Mariana P. Barcelos
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCar, São Carlos, São Paulo, Brazil
| | - Nicole C. S. Nicolela
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCar, São Carlos, São Paulo, Brazil
| | - Evandro L. Prieto
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCar, São Carlos, São Paulo, Brazil
| | - Leandro S. Goto
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCar, São Carlos, São Paulo, Brazil
| | - José Belasque
- Departamento de Fitopatologia e Nematologia, Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, USP, Piracicaba, São Paulo, Brazil
| | - Maria Teresa Marques Novo-Mansur
- Laboratório de Bioquímica e Biologia Molecular Aplicada, Departamento de Genética e Evolução, Universidade Federal de São Carlos, UFSCar, São Carlos, São Paulo, Brazil
- * E-mail:
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12
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Corrêa CL, Midorikawa GEO, Filho EXF, Noronha EF, Alves GSC, Togawa RC, Silva-Junior OB, Costa MMDC, Grynberg P, Miller RNG. Transcriptome Profiling-Based Analysis of Carbohydrate-Active Enzymes in Aspergillus terreus Involved in Plant Biomass Degradation. Front Bioeng Biotechnol 2020; 8:564527. [PMID: 33123513 PMCID: PMC7573219 DOI: 10.3389/fbioe.2020.564527] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 09/16/2020] [Indexed: 11/13/2022] Open
Abstract
Given the global abundance of plant biomass residues, potential exists in biorefinery-based applications with lignocellulolytic fungi. Frequently isolated from agricultural cellulosic materials, Aspergillus terreus is a fungus efficient in secretion of commercial enzymes such as cellulases, xylanases and phytases. In the context of biomass saccharification, lignocellulolytic enzyme secretion was analyzed in a strain of A. terreus following liquid culture with sugarcane bagasse (SB) (1% w/v) and soybean hulls (SH) (1% w/v) as sole carbon source, in comparison to glucose (G) (1% w/v). Analysis of the fungal secretome revealed a maximum of 1.017 UI.mL–1 xylanases after growth in minimal medium with SB, and 1.019 UI.mL–1 after incubation with SH as carbon source. The fungal transcriptome was characterized on SB and SH, with gene expression examined in comparison to equivalent growth on G as carbon source. Over 8000 genes were identified, including numerous encoding enzymes and transcription factors involved in the degradation of the plant cell wall, with significant expression modulation according to carbon source. Eighty-nine carbohydrate-active enzyme (CAZyme)-encoding genes were identified following growth on SB, of which 77 were differentially expressed. These comprised 78% glycoside hydrolases, 8% carbohydrate esterases, 2.5% polysaccharide lyases, and 11.5% auxiliary activities. Analysis of the glycoside hydrolase family revealed significant up-regulation for genes encoding 25 different GH family proteins, with predominance for families GH3, 5, 7, 10, and 43. For SH, from a total of 91 CAZyme-encoding genes, 83 were also significantly up-regulated in comparison to G. These comprised 80% glycoside hydrolases, 7% carbohydrate esterases, 5% polysaccharide lyases, 7% auxiliary activities (AA), and 1% glycosyltransferases. Similarly, within the glycoside hydrolases, significant up-regulation was observed for genes encoding 26 different GH family proteins, with predominance again for families GH3, 5, 10, 31, and 43. A. terreus is a promising species for production of enzymes involved in the degradation of plant biomass. Given that this fungus is also able to produce thermophilic enzymes, this first global analysis of the transcriptome following cultivation on lignocellulosic carbon sources offers considerable potential for the application of candidate genes in biorefinery applications.
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Affiliation(s)
- Camila L Corrêa
- Departamento de Biologia Celular, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, Brazil
| | - Glaucia E O Midorikawa
- Departamento de Biologia Celular, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, Brazil
| | | | - Eliane Ferreira Noronha
- Departamento de Biologia Celular, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, Brazil
| | - Gabriel S C Alves
- Departamento de Biologia Celular, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, Brazil
| | - Roberto Coiti Togawa
- Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica - PqEB, Brasília, Brazil
| | | | | | - Priscila Grynberg
- Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica - PqEB, Brasília, Brazil
| | - Robert N G Miller
- Departamento de Biologia Celular, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, Brazil
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Lenz AR, Galán-Vásquez E, Balbinot E, de Abreu FP, Souza de Oliveira N, da Rosa LO, de Avila e Silva S, Camassola M, Dillon AJP, Perez-Rueda E. Gene Regulatory Networks of Penicillium echinulatum 2HH and Penicillium oxalicum 114-2 Inferred by a Computational Biology Approach. Front Microbiol 2020; 11:588263. [PMID: 33193246 PMCID: PMC7652724 DOI: 10.3389/fmicb.2020.588263] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 09/23/2020] [Indexed: 11/29/2022] Open
Abstract
Penicillium echinulatum 2HH and Penicillium oxalicum 114-2 are well-known cellulase fungal producers. However, few studies addressing global mechanisms for gene regulation of these two important organisms are available so far. A recent finding that the 2HH wild-type is closely related to P. oxalicum leads to a combined study of these two species. Firstly, we provide a global gene regulatory network for P. echinulatum 2HH and P. oxalicum 114-2, based on TF-TG orthology relationships, considering three related species with well-known regulatory interactions combined with TFBSs prediction. The network was then analyzed in terms of topology, identifying TFs as hubs, and modules. Based on this approach, we explore numerous identified modules, such as the expression of cellulolytic and xylanolytic systems, where XlnR plays a key role in positive regulation of the xylanolytic system. It also regulates positively the cellulolytic system by acting indirectly through the cellodextrin induction system. This remarkable finding suggests that the XlnR-dependent cellulolytic and xylanolytic regulatory systems are probably conserved in both P. echinulatum and P. oxalicum. Finally, we explore the functional congruency on the genes clustered in terms of communities, where the genes related to cellular nitrogen, compound metabolic process and macromolecule metabolic process were the most abundant. Therefore, our approach allows us to confer a degree of accuracy regarding the existence of each inferred interaction.
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Affiliation(s)
- Alexandre Rafael Lenz
- Unidad Académica Yucatán, Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de Mexico, Mérida, Mexico
- Laboratório de Bioinformática e Biologia Computacional, Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, Brazil
- Departamento de Ciências Exatas e da Terra, Universidade do Estado da Bahia, Salvador, Brazil
| | - Edgardo Galán-Vásquez
- Departamento de Ingeniería de Sistemas Computacionales y Automatización, Instituto de Investigaciones en Matemàticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de Mexico, Ciudad Universitaria, Mexico
| | - Eduardo Balbinot
- Laboratório de Bioinformática e Biologia Computacional, Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, Brazil
| | - Fernanda Pessi de Abreu
- Laboratório de Bioinformática e Biologia Computacional, Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, Brazil
| | - Nikael Souza de Oliveira
- Laboratório de Bioinformática e Biologia Computacional, Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, Brazil
- Laboratório de Enzimas e Biomassas, Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, Brazil
| | - Letícia Osório da Rosa
- Laboratório de Enzimas e Biomassas, Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, Brazil
| | - Scheila de Avila e Silva
- Laboratório de Bioinformática e Biologia Computacional, Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, Brazil
| | - Marli Camassola
- Laboratório de Enzimas e Biomassas, Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, Brazil
| | - Aldo José Pinheiro Dillon
- Laboratório de Enzimas e Biomassas, Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, Brazil
| | - Ernesto Perez-Rueda
- Unidad Académica Yucatán, Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de Mexico, Mérida, Mexico
- Facultad de Ciencias, Centro de Genómica y Bioinformática, Universidad Mayor, Santiago, Chile
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Multi-omic Directed Discovery of Cellulosomes, Polysaccharide Utilization Loci, and Lignocellulases from an Enriched Rumen Anaerobic Consortium. Appl Environ Microbiol 2020; 86:AEM.00199-20. [PMID: 32680862 PMCID: PMC7480376 DOI: 10.1128/aem.00199-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 07/10/2020] [Indexed: 01/04/2023] Open
Abstract
The lignocellulolytic ERAC displays a unique set of plant polysaccharide-degrading enzymes (with multimodular characteristics), cellulosomal complexes, and PULs. The MAGs described here represent an expansion of the genetic content of rumen bacterial genomes dedicated to plant polysaccharide degradation, therefore providing a valuable resource for the development of biocatalytic toolbox strategies to be applied to lignocellulose-based biorefineries. Lignocellulose is one of the most abundant renewable carbon sources, representing an alternative to petroleum for the production of fuel and chemicals. Nonetheless, the lignocellulose saccharification process, to release sugars for downstream applications, is one of the most crucial factors economically challenging to its use. The synergism required among the various carbohydrate-active enzymes (CAZymes) for efficient lignocellulose breakdown is often not satisfactorily achieved with an enzyme mixture from a single strain. To overcome this challenge, enrichment strategies can be applied to develop microbial communities with an efficient CAZyme arsenal, incorporating complementary and synergistic properties, to improve lignocellulose deconstruction. We report a comprehensive and deep analysis of an enriched rumen anaerobic consortium (ERAC) established on sugarcane bagasse (SB). The lignocellulolytic abilities of the ERAC were confirmed by analyzing the depolymerization of bagasse by scanning electron microscopy, enzymatic assays, and mass spectrometry. Taxonomic analysis based on 16S rRNA sequencing elucidated the community enrichment process, which was marked by a higher abundance of Firmicutes and Synergistetes species. Shotgun metagenomic sequencing of the ERAC disclosed 41 metagenome-assembled genomes (MAGs) harboring cellulosomes and polysaccharide utilization loci (PULs), along with a high diversity of CAZymes. The amino acid sequences of the majority of the predicted CAZymes (60% of the total) shared less than 90% identity with the sequences found in public databases. Additionally, a clostridial MAG identified in this study produced proteins during consortium development with scaffoldin domains and CAZymes appended to dockerin modules, thus representing a novel cellulosome-producing microorganism. IMPORTANCE The lignocellulolytic ERAC displays a unique set of plant polysaccharide-degrading enzymes (with multimodular characteristics), cellulosomal complexes, and PULs. The MAGs described here represent an expansion of the genetic content of rumen bacterial genomes dedicated to plant polysaccharide degradation, therefore providing a valuable resource for the development of biocatalytic toolbox strategies to be applied to lignocellulose-based biorefineries.
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15
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Niu J, Zhao G, Mi Z, Chen L, Liu S, Wang S, Wang D, Wang Z. De novo sequencing of Bletilla striata (Orchidaceae) transcriptome and identification of genes involved in polysaccharide biosynthesis. Genet Mol Biol 2020; 43:e20190417. [PMID: 32609279 PMCID: PMC7315133 DOI: 10.1590/1678-4685-gmb-2019-0417] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 04/16/2020] [Indexed: 11/22/2022] Open
Abstract
Bletilla striata polysaccharide (BSP) is the main component of Bletilla striata, which has important pharmacological and pharmacological effects; however, due to the lack of genetic data, the metabolic pathways of BSP remain unclear. For this study, 11 representative resources of B. striata were analyzed, and the BSP contents of the different samples were significantly different; however, the monosaccharide composition of BSP was glucose and mannose. The representative samples were selected to observe their life history in situ, which were then divided and cultured in a greenhouse. Finally, samples from various organs of different plants were combined for transcriptome sequencing using the Illumina system. Our results summarized the BSP metabolic pathway, and we found that there were eight enzyme genes involved in biosynthesis, but these genes showed tissue specificity. Following qRT-PCR validation and comparative analysis, manA showed the highest expression; however, there were significant differences between the two germplasm resources in which the BSP content was significantly different, while UGP2, GPI, PMM, and GMPP had significant differences between the two samples. In summary, this study lays the foundation for further research into BSP metabolism and other physiological processes at the molecular level.
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Affiliation(s)
- Junfeng Niu
- Shaanxi Normal University, College of Life Sciences, Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Xi'an, Shaanxi, China
| | - Guangming Zhao
- Shaanxi Normal University, College of Life Sciences, Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Xi'an, Shaanxi, China
| | - Zeyuan Mi
- Shaanxi Normal University, College of Life Sciences, Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Xi'an, Shaanxi, China
| | - Lijun Chen
- Shaanxi Normal University, College of Life Sciences, Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Xi'an, Shaanxi, China
| | - Shuai Liu
- Shaanxi Normal University, College of Life Sciences, Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Xi'an, Shaanxi, China
| | - Shiqiang Wang
- Shaanxi Normal University, College of Life Sciences, Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Xi'an, Shaanxi, China
| | - Donghao Wang
- Shaanxi Normal University, College of Life Sciences, Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Xi'an, Shaanxi, China
| | - Zhezhi Wang
- Shaanxi Normal University, College of Life Sciences, Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest of China, Xi'an, Shaanxi, China
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Díaz GV, Coniglio RO, Alvarenga AE, Zapata PD, Villalba LL, Fonseca MI. Secretomic analysis of cheap enzymatic cocktails of Aspergillus niger LBM 134 grown on cassava bagasse and sugarcane bagasse. Mycologia 2020; 112:663-676. [PMID: 32574526 DOI: 10.1080/00275514.2020.1763707] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Currently, agroindustrial wastes are little used for generating value-added products; hence, their use of these waste to produce enzymatic cocktails for the conversion of lignocellulosic biomass to fermentable sugars is a very interesting alternative in the second-generation bioethanol process. The Ascomycota fungus Aspergillus niger LBM 134 produces hydrolytic enzymes in large proportions. In this work, A. niger LBM 134 was grown on sugarcane and cassava bagasses under optimized conditions. To identify the extracellular enzymes involved in the degradation of these agroindustrial wastes, the secretomes of the culture supernatants of the fungus were analyzed and validated by biochemical assays of the enzymatic activities. A. niger LBM 134 secreted higher quantities of xylanases and accessory hemicellulases when it grew on sugarcane bagasse, whereas more cellulases, amylases, and pectinases were secreted when it grew on cassava bagasse. These findings suggest two promising enzyme cocktails for the hydrolysis of lignocellulose carbohydrate polymers to fermentable sugars. These bioinformatic analysis were functional validates through enzymatic biochemical assays that confirm the biotechnological potential of A. niger LBM 134 for the bioconversion of hemicellulosic substrates such as sugarcane and cassava bagasses.
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Affiliation(s)
- Gabriela Verónica Díaz
- Laboratorio de Biotecnología Molecular, Instituto de Biotecnología Misiones "María Ebe Reca" CONICET, Facultad de Ciencias Exactas, Químicas y Naturales, Universidad Nacional de Misiones , Ruta 12 km 7.5, C.P. 3300, Posadas, Argentina
| | - Romina Olga Coniglio
- Laboratorio de Biotecnología Molecular, Instituto de Biotecnología Misiones "María Ebe Reca" CONICET, Facultad de Ciencias Exactas, Químicas y Naturales, Universidad Nacional de Misiones , Ruta 12 km 7.5, C.P. 3300, Posadas, Argentina
| | - Adriana Elizabet Alvarenga
- Laboratorio de Biotecnología Molecular, Instituto de Biotecnología Misiones "María Ebe Reca" CONICET, Facultad de Ciencias Exactas, Químicas y Naturales, Universidad Nacional de Misiones , Ruta 12 km 7.5, C.P. 3300, Posadas, Argentina
| | - Pedro Darío Zapata
- Laboratorio de Biotecnología Molecular, Instituto de Biotecnología Misiones "María Ebe Reca" CONICET, Facultad de Ciencias Exactas, Químicas y Naturales, Universidad Nacional de Misiones , Ruta 12 km 7.5, C.P. 3300, Posadas, Argentina
| | - Laura Lidia Villalba
- Laboratorio de Biotecnología Molecular, Instituto de Biotecnología Misiones "María Ebe Reca" CONICET, Facultad de Ciencias Exactas, Químicas y Naturales, Universidad Nacional de Misiones , Ruta 12 km 7.5, C.P. 3300, Posadas, Argentina
| | - María Isabel Fonseca
- Laboratorio de Biotecnología Molecular, Instituto de Biotecnología Misiones "María Ebe Reca" CONICET, Facultad de Ciencias Exactas, Químicas y Naturales, Universidad Nacional de Misiones , Ruta 12 km 7.5, C.P. 3300, Posadas, Argentina
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Adsul M, Sandhu SK, Singhania RR, Gupta R, Puri SK, Mathur A. Designing a cellulolytic enzyme cocktail for the efficient and economical conversion of lignocellulosic biomass to biofuels. Enzyme Microb Technol 2019; 133:109442. [PMID: 31874688 DOI: 10.1016/j.enzmictec.2019.109442] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 10/03/2019] [Accepted: 10/04/2019] [Indexed: 11/19/2022]
Abstract
Concerns about dwindling fossil fuels and their unfavorable environmental impacts shifted the global focus towards the development of biofuels from lignocellulosic feedstocks. The structure of this biomass is very complex due to which variety of enzymes (cellulolytic, hemicellulolytic, auxiliary/AA9) and proteins (e.g. swollenin) required for efficient deconstruction. Major impediments in large-scale commercial production of cellulosic ethanol are the cost of cellulases and inability of any single microorganism to produce all cellulolytic components in sufficient titers. In the recent past, various methods for reducing the enzyme cost during cellulosic ethanol production have been attempted. These include designing optimal synergistic enzyme blends/cocktail, having certain ratios of enzymes from different microbial sources, for efficient hydrolysis of pretreated biomass. However, the mechanisms underlying the development, strategies for production and evaluation of optimal cellulolytic cocktails still remain unclear. This article aims to explore the technical and economic benefits of using cellulolytic enzyme cocktail, basic enzymatic and non-enzymatic components required for its development and various strategies employed for efficient cellulolytic cocktail preparation. Consideration was also given to the ways of evaluation of commercially available and in-house developed cocktails. Discussion about commercially available cellulolytic cocktails, current challenges and possible avenues in the development of cellulolytic cocktails included.
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Affiliation(s)
- Mukund Adsul
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India.
| | - Simranjeet Kaur Sandhu
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Reeta Rani Singhania
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Ravi Gupta
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Suresh K Puri
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Anshu Mathur
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
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Mosina NL, Schubert WD, Cowan DA. Characterization and homology modelling of a novel multi-modular and multi-functional Paenibacillus mucilaginosus glycoside hydrolase. Extremophiles 2019; 23:681-686. [PMID: 31372752 DOI: 10.1007/s00792-019-01121-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 07/21/2019] [Indexed: 10/26/2022]
Abstract
Glycoside hydrolases, particularly cellulases, xylanases and mannanases, are essential for the depolymerisation of lignocellulosic substrates in various industrial bio-processes. In the present study, a novel glycoside hydrolase from Paenibacillus mucilaginosus (PmGH) was expressed in E. coli, purified and characterised. Functional analysis indicated that PmGH is a 130 kDa thermophilic multi-modular and multi-functional enzyme, comprising a GH5, a GH6 and two CBM3 domains and exhibiting cellulase, mannanase and xylanase activities. The enzyme displayed optimum hydrolytic activities at pH 6 and 60 °C and moderate thermostability. Homology modelling of the full-length protein highlighted the structural and functional novelty of native PmGH, with no close structural homologs identified. However, homology modelling of the individual GH5, GH6 and the two CBM3 domains yielded excellent models based on related structures from the Protein Data Bank. The catalytic GH5 and GH6 domains displayed a (β/α)8 and a distorted seven stranded (β/α) fold, respectively. The distinct homology at the domain level but low homology of the full-length protein suggests that this protein evolved by exogenous gene acquisition and recombination.
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Affiliation(s)
- Ntsoaki Leticia Mosina
- Department Biochemistry, Genetics and Microbiology, Centre for Microbial Ecology and Genomics, University of Pretoria, Lynnwood Road, Hatfield, Pretoria, 0002, South Africa
| | - Wolf-Dieter Schubert
- Department Biochemistry, Genetics and Microbiology, Centre for Microbial Ecology and Genomics, University of Pretoria, Lynnwood Road, Hatfield, Pretoria, 0002, South Africa
| | - Don A Cowan
- Department Biochemistry, Genetics and Microbiology, Centre for Microbial Ecology and Genomics, University of Pretoria, Lynnwood Road, Hatfield, Pretoria, 0002, South Africa.
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19
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Mardones W, Callegari E, Eyzaguirre J. Corncob and sugar beet pulp induce specific sets of lignocellulolytic enzymes in Penicillium purpurogenum. Mycology 2019; 10:118-125. [PMID: 31069125 PMCID: PMC6493289 DOI: 10.1080/21501203.2018.1517830] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 08/26/2018] [Indexed: 01/19/2023] Open
Abstract
Penicillium purpurogenum is a filamentous fungus, which grows on a variety of natural carbon sources and secretes a large number of enzymes involved in cellulose, hemicelluloses and pectin biodegradation. The purpose of this work has been to identify potential lignocellulolytic enzymes and to compare the secreted enzymes produced when the fungus is grown on sugar beet pulp (rich in cellulose and pectin) and corn cob (rich in cellulose and xylan). Culture supernatants were subjected to two-dimensional nano-liquid chromatography/tandem mass spectrometry. Using MASCOT and a genome-derived protein database, the proteins present in the supernatant were identified. The putative function in the degradation of the polysaccharides was determined using dbCAN software. The results show that there is a good correlation between the polysaccharide composition of the carbon sources and the function of the secreted enzymes: both cultures are rich in cellulases, while sugar beet pulp induces pectinases and corncob, xylanases. The eventual biochemical characterisation of these enzymes will be of value for a better understanding of the biodegradation process performed by the fungus and increase the availability of enzymes for biotechnological methods associated with this process.
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Affiliation(s)
- Wladimir Mardones
- Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Eduardo Callegari
- BRIN-USDSSOM Proteomics Facility, University of South Dakota, Vermillion, SD, USA
| | - Jaime Eyzaguirre
- Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
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Lignocellulolytic characterization and comparative secretome analysis of a Trichoderma erinaceum strain isolated from decaying sugarcane straw. Fungal Biol 2019; 123:330-340. [PMID: 30928041 DOI: 10.1016/j.funbio.2019.01.007] [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: 07/28/2018] [Revised: 01/18/2019] [Accepted: 01/24/2019] [Indexed: 11/21/2022]
Abstract
The fungus Trichoderma reesei is employed in the production of most enzyme cocktails used by the lignocellulosic biofuels industry today. Despite significant improvements, the cost of the required enzyme preparations remains high, representing a major obstacle for the industrial production of these alternative fuels. In this study, a new Trichoderma erinaceum strain was isolated from decaying sugarcane straw. The enzyme cocktail secreted by the new isolate during growth in pretreated sugarcane straw-containing medium presented higher specific activities of β-glucosidase, endoxylanase, β-xylosidase and α-galactosidase than the cocktail of a wild T. reesei strain and yielded more glucose in the hydrolysis of pretreated sugarcane straw. A proteomic analysis of the two strains' secretomes identified a total of 86 proteins, of which 48 were exclusive to T. erinaceum, 35 were exclusive to T. reesei and only 3 were common to both strains. The secretome of T. erinaceum also displayed a higher number of carbohydrate-active enzymes than that of T. reesei (37 and 27 enzymes, respectively). Altogether, these results reveal the significant potential of the T. erinaceum species for the production of lignocellulases, both as a possible source of enzymes for the supplementation of industrial cocktails and as a candidate chassis for enzyme production.
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Guo H, Wang XD, Lee DJ. Proteomic researches for lignocellulose-degrading enzymes: A mini-review. BIORESOURCE TECHNOLOGY 2018; 265:532-541. [PMID: 29884341 DOI: 10.1016/j.biortech.2018.05.101] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 05/29/2018] [Accepted: 05/30/2018] [Indexed: 05/14/2023]
Abstract
Protective action of lignin/hemicellulose networks and crystalline structures of embedded cellulose render lignocellulose material resistant to external enzymatic attack. To eliminate this bottleneck, research has been conducted in which advanced proteomic techniques are applied to identify effective commercial hydrolytic enzymes. This mini-review summarizes researches on lignocellulose-degrading enzymes, the mechanisms of the responses of various lignocellulose-degrading strains and microbial communities to various carbon sources and various biomass substrates, post-translational modifications of lignocellulose-degrading enzymes, new lignocellulose-degrading strains, new lignocellulose-degrading enzymes and a new method of secretome analysis. The challenges in the practical use of enzymatic hydrolysis process to realize lignocellulose biorefineries are discussed, along with the prospects for the same.
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Affiliation(s)
- Hongliang Guo
- College of Food Engineering, Harbin University of Commerce, Harbin 150076, China
| | - Xiao-Dong Wang
- Research Center of Engineering Thermophysics, North China Electric Power University, Beijing 102206, China; School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan; Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan.
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de Gouvêa PF, Bernardi AV, Gerolamo LE, de Souza Santos E, Riaño-Pachón DM, Uyemura SA, Dinamarco TM. Transcriptome and secretome analysis of Aspergillus fumigatus in the presence of sugarcane bagasse. BMC Genomics 2018; 19:232. [PMID: 29614953 PMCID: PMC5883313 DOI: 10.1186/s12864-018-4627-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 03/27/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Sugarcane bagasse has been proposed as a lignocellulosic residue for second-generation ethanol (2G) produced by breaking down biomass into fermentable sugars. The enzymatic cocktails for biomass degradation are mostly produced by fungi, but low cost and high efficiency can consolidate 2G technologies. A. fumigatus plays an important role in plant biomass degradation capabilities and recycling. To gain more insight into the divergence in gene expression during steam-exploded bagasse (SEB) breakdown, this study profiled the transcriptome of A. fumigatus by RNA sequencing to compare transcriptional profiles of A. fumigatus grown on media containing SEB or fructose as the sole carbon source. Secretome analysis was also performed using SDS-PAGE and LC-MS/MS. RESULTS The maximum activities of cellulases (0.032 U mL-1), endo-1,4-β--xylanase (10.82 U mL-1) and endo-1,3-β glucanases (0.77 U mL-1) showed that functional CAZymes (carbohydrate-active enzymes) were secreted in the SEB culture conditions. Correlations between transcriptome and secretome data identified several CAZymes in A. fumigatus. Particular attention was given to CAZymes related to lignocellulose degradation and sugar transporters. Genes encoding glycoside hydrolase classes commonly expressed during the breakdown of cellulose, such as GH-5, 6, 7, 43, 45, and hemicellulose, such as GH-2, 10, 11, 30, 43, were found to be highly expressed in SEB conditions. Lytic polysaccharide monooxygenases (LPMO) classified as auxiliary activity families AA9 (GH61), CE (1, 4, 8, 15, 16), PL (1, 3, 4, 20) and GT (1, 2, 4, 8, 20, 35, 48) were also differentially expressed in this condition. Similarly, the most important enzymes related to biomass degradation, including endoxylanases, xyloglucanases, β-xylosidases, LPMOs, α-arabinofuranosidases, cellobiohydrolases, endoglucanases and β-glucosidases, were also identified in the secretome. CONCLUSIONS This is the first report of a transcriptome and secretome experiment of Aspergillus fumigatus in the degradation of pretreated sugarcane bagasse. The results suggest that this strain employs important strategies for this complex degradation process. It was possible to identify a set of genes and proteins that might be applied in several biotechnology fields. This knowledge can be exploited for the improvement of 2G ethanol production by the rational design of enzymatic cocktails.
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Affiliation(s)
- Paula Fagundes de Gouvêa
- Faculty of Philosophy, Sciences and Literature of Ribeirão Preto, Chemistry Department, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Aline Vianna Bernardi
- Faculty of Philosophy, Sciences and Literature of Ribeirão Preto, Chemistry Department, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Luis Eduardo Gerolamo
- Faculty of Philosophy, Sciences and Literature of Ribeirão Preto, Chemistry Department, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Emerson de Souza Santos
- Faculty of Pharmaceutical Science, Department of Clinical, Toxicological and Bromatological Analysis, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Diego Mauricio Riaño-Pachón
- Brazilian Bioethanol Science and Technology Laboratory, Campinas, São Paulo, Brazil
- Current address: Laboratory of Regulatory Systems Biology, Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Sergio Akira Uyemura
- Faculty of Pharmaceutical Science, Department of Clinical, Toxicological and Bromatological Analysis, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Taisa Magnani Dinamarco
- Faculty of Philosophy, Sciences and Literature of Ribeirão Preto, Chemistry Department, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
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Schneider WDH, Gonçalves TA, Uchima CA, Reis LD, Fontana RC, Squina FM, Dillon AJP, Camassola M. Comparison of the production of enzymes to cell wall hydrolysis using different carbon sources by Penicillium echinulatum strains and its hydrolysis potential for lignocelullosic biomass. Process Biochem 2018. [DOI: 10.1016/j.procbio.2017.11.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Cologna NDMD, Gómez-Mendoza DP, Zanoelo FF, Giannesi GC, Guimarães NCDA, Moreira LRDS, Filho EXF, Ricart CAO. Exploring Trichoderma and Aspergillus secretomes: Proteomics approaches for the identification of enzymes of biotechnological interest. Enzyme Microb Technol 2018; 109:1-10. [DOI: 10.1016/j.enzmictec.2017.08.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 08/17/2017] [Accepted: 08/18/2017] [Indexed: 12/13/2022]
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GH62 arabinofuranosidases: Structure, function and applications. Biotechnol Adv 2017; 35:792-804. [DOI: 10.1016/j.biotechadv.2017.06.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 06/17/2017] [Accepted: 06/23/2017] [Indexed: 01/03/2023]
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Damasio ARDL, Rubio MV, Gonçalves TA, Persinoti GF, Segato F, Prade RA, Contesini FJ, de Souza AP, Buckeridge MS, Squina FM. Xyloglucan breakdown by endo-xyloglucanase family 74 from Aspergillus fumigatus. Appl Microbiol Biotechnol 2016; 101:2893-2903. [PMID: 28013403 DOI: 10.1007/s00253-016-8014-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Revised: 11/09/2016] [Accepted: 11/12/2016] [Indexed: 12/30/2022]
Abstract
Xyloglucan is the most abundant hemicellulose in primary walls of spermatophytes except for grasses. Xyloglucan-degrading enzymes are important in lignocellulosic biomass hydrolysis because they remove xyloglucan, which is abundant in monocot-derived biomass. Fungal genomes encode numerous xyloglucanase genes, belonging to at least six glycoside hydrolase (GH) families. GH74 endo-xyloglucanases cleave xyloglucan backbones with unsubstituted glucose at the -1 subsite or prefer xylosyl-substituted residues in the -1 subsite. In this work, 137 GH74-related genes were detected by examining 293 Eurotiomycete genomes and Ascomycete fungi contained one or no GH74 xyloglucanase gene per genome. Another interesting feature is that the triad of tryptophan residues along the catalytic cleft was found to be widely conserved among Ascomycetes. The GH74 from Aspergillus fumigatus (AfXEG74) was chosen as an example to conduct comprehensive biochemical studies to determine the catalytic mechanism. AfXEG74 has no CBM and cleaves the xyloglucan backbone between the unsubstituted glucose and xylose-substituted glucose at specific positions, along the XX motif when linked to regions deprived of galactosyl branches. It resembles an endo-processive activity, which after initial random hydrolysis releases xyloglucan-oligosaccharides as major reaction products. This work provides insights on phylogenetic diversity and catalytic mechanism of GH74 xyloglucanases from Ascomycete fungi.
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Affiliation(s)
- André Ricardo de Lima Damasio
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil.,Department of Biochemistry and Tissue Biology, Institute of Biology, State University of Campinas, Campinas, SP, Brazil
| | - Marcelo Ventura Rubio
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil.,Department of Biochemistry and Tissue Biology, Institute of Biology, State University of Campinas, Campinas, SP, Brazil
| | - Thiago Augusto Gonçalves
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil.,Department of Biochemistry and Tissue Biology, Institute of Biology, State University of Campinas, Campinas, SP, Brazil
| | - Gabriela Felix Persinoti
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil
| | - Fernando Segato
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil.,Departamento de Biotecnologia, Escola de Engenharia de Lorena (EEL), Universidade de São Paulo (USP), Lorena, SP, Brazil
| | - Rolf Alexander Prade
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Fabiano Jares Contesini
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil
| | - Amanda Pereira de Souza
- Laboratório de Fisiologia e Ecologia de Plantas (LAFIECO), Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | - Marcos Silveira Buckeridge
- Laboratório de Fisiologia e Ecologia de Plantas (LAFIECO), Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo (USP), São Paulo, SP, Brazil
| | - Fabio Marcio Squina
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil.
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Rubio MV, Zubieta MP, Franco Cairo JPL, Calzado F, Paes Leme AF, Squina FM, Prade RA, de Lima Damásio AR. Mapping N-linked glycosylation of carbohydrate-active enzymes in the secretome of Aspergillus nidulans grown on lignocellulose. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:168. [PMID: 27508003 PMCID: PMC4977673 DOI: 10.1186/s13068-016-0580-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 07/27/2016] [Indexed: 05/06/2023]
Abstract
BACKGROUND The genus Aspergillus includes microorganisms that naturally degrade lignocellulosic biomass, secreting large amounts of carbohydrate-active enzymes (CAZymes) that characterize their saprophyte lifestyle. Aspergillus has the capacity to perform post-translational modifications (PTM), which provides an additional advantage for the use of these organisms as a host for the production of heterologous proteins. In this study, the N-linked glycosylation of CAZymes identified in the secretome of Aspergillus nidulans grown on lignocellulose was mapped. RESULTS Aspergillus nidulans was grown in glucose, xylan and pretreated sugarcane bagasse (SCB) for 96 h, after which glycoproteomics and glycomics were carried out on the extracellular proteins (secretome). A total of 265 proteins were identified, with 153, 210 and 182 proteins in the glucose, xylan and SCB substrates, respectively. CAZymes corresponded to more than 50 % of the total secretome in xylan and SCB. A total of 182 N-glycosylation sites were identified, of which 121 were detected in 67 CAZymes. A prevalence of the N-glyc sequon N-X-T (72.2 %) was observed in N-glyc sites compared with N-X-S (27.8 %). The amino acids flanking the validated N-glyc sites were mainly composed of hydrophobic and polar uncharged amino acids. Selected proteins were evaluated for conservation of the N-glyc sites in Aspergilli homologous proteins, but a pattern of conservation was not observed. A global analysis of N-glycans released from the proteins secreted by A. nidulans was also performed. While the proportion of N-glycans with Hex5 to Hex9 was similar in the xylan condition, a prevalence of Hex5 was observed in the SCB and glucose conditions. CONCLUSIONS The most common and frequent N-glycosylated motifs, an overview of the N-glycosylation of the CAZymes and the number of mannoses found in N-glycans were analyzed. There are many bottlenecks in protein production by filamentous fungi, such as folding, transport by vesicles and secretion, but N-glycosylation in the correct context is a fundamental event for defining the high levels of secretion of target proteins. A comprehensive analysis of the protein glycosylation processes in A. nidulans will assist with a better understanding of glycoprotein structures, profiles, activities and functions. This knowledge can help in the optimization of heterologous expression and protein secretion in the fungal host.
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Affiliation(s)
- Marcelo Ventura Rubio
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP Brazil
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), Rua Monteiro Lobato, 255, Cidade Universitária Zeferino Vaz, Campinas, SP 13083-862 Brazil
| | - Mariane Paludetti Zubieta
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP Brazil
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), Rua Monteiro Lobato, 255, Cidade Universitária Zeferino Vaz, Campinas, SP 13083-862 Brazil
| | - João Paulo Lourenço Franco Cairo
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP Brazil
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), Rua Monteiro Lobato, 255, Cidade Universitária Zeferino Vaz, Campinas, SP 13083-862 Brazil
| | - Felipe Calzado
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP Brazil
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), Rua Monteiro Lobato, 255, Cidade Universitária Zeferino Vaz, Campinas, SP 13083-862 Brazil
| | - Adriana Franco Paes Leme
- Laboratório Nacional de Biociências (LNBio), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP Brazil
| | - Fabio Marcio Squina
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP Brazil
| | - Rolf Alexander Prade
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK USA
| | - André Ricardo de Lima Damásio
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP Brazil
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), Rua Monteiro Lobato, 255, Cidade Universitária Zeferino Vaz, Campinas, SP 13083-862 Brazil
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Xylan-specific carbohydrate-binding module belonging to family 6 enhances the catalytic performance of a GH11 endo-xylanase. N Biotechnol 2016; 33:467-72. [DOI: 10.1016/j.nbt.2016.02.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Revised: 01/18/2016] [Accepted: 02/16/2016] [Indexed: 01/09/2023]
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Enhancement of Penicillium echinulatum glycoside hydrolase enzyme complex. ACTA ACUST UNITED AC 2016; 43:627-39. [DOI: 10.1007/s10295-016-1746-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 02/05/2016] [Indexed: 01/01/2023]
Abstract
Abstract
The enhancement of enzyme complex produced by Penicillium echinulatum grown in several culture media components (bagasse sugarcane pretreated by various methods, soybean meal, wheat bran, sucrose, and yeast extract) was studied to increment FPase, xylanase, pectinase, and β-glucosidase enzyme activities. The present results indicated that culture media composed with 10 g/L of the various bagasse pretreatment methods did not have any substantial influence with respect to the FPase, xylanase, and β-glucosidase attained maximum values of, respectively, 2.68 FPU/mL, 2.04, and 115.4 IU/mL. On the other hand, proposed culture media to enhance β-glucosidase production composed of 10 g/L steam-exploded bagasse supplemented with soybean flour 5.0 g/L, yeast extract 1.0 g/L, and sucrose 10.0 g/L attained, respectively, 3.19 FPU/mL and 3.06 IU/mL while xylanase was maintained at the same level. The proteomes obtained from the optimized culture media for enhanced FPase, xylanase, pectinase, and β-glucosidase production were analyzed using mass spectrometry and a panel of GH enzyme activities against 16 different substrates. Culture medium designed to enhance β-glucosidase activity achieved higher enzymatic activities values (13 measured activities), compared to the culture media for FPase/pectinase (9 measured activities) and xylanase (7 measured activities), when tested against the 16 substrates. Mass spectrometry analyses of secretome showed a consistent result and the greatest number of spectral counts of Cazy family enzymes was found in designed β-glucosidase culture medium, followed by FPase/pectinase and xylanase. Most of the Cazy identified protein was cellobiohydrolase (GH6 and GH7), endoglucanase (GH5), and endo-1,4-β-xylanase (GH10). Enzymatic hydrolysis of hydrothermally pretreated sugarcane bagasse performed with β-glucosidase enhanced cocktail achieved 51.4 % glucose yield with 10 % w/v insoluble solids at enzyme load of 15 FPU/g material. Collectively the results demonstrated that it was possible to rationally modulate the GH activity of the enzymatic complex secreted by P. echinulatum using adjustment of the culture medium composition. The proposed strategy may contribute to increase enzymatic hydrolysis of lignocellulosic materials.
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Schneider WDH, Gonçalves TA, Uchima CA, Couger MB, Prade R, Squina FM, Dillon AJP, Camassola M. Penicillium echinulatum secretome analysis reveals the fungi potential for degradation of lignocellulosic biomass. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:66. [PMID: 26989443 PMCID: PMC4794826 DOI: 10.1186/s13068-016-0476-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 03/02/2016] [Indexed: 05/25/2023]
Abstract
BACKGROUND The enzymatic degradation of lignocellulosic materials by fungal enzyme systems has been extensively studied due to its effectiveness in the liberation of fermentable sugars for bioethanol production. Recently, variants of the fungus Penicillium echinulatum have been described as a great producer of cellulases and considered a promising strain for the bioethanol industry. RESULTS Penicillium echinulatum, wild-type 2HH and its mutant strain S1M29, were grown on four different carbon sources: cellulose, sugar cane bagasse pretreated by steam explosion (SCB), glucose, and glycerol for 120 h. Samples collected at 24, 96, and 120 h were used for enzymatic measurement, and the 96-h one was also used for secretome analysis by 1D-PAGE LC-MS/MS. A total of 165 proteins were identified, and more than one-third of these proteins belong to CAZy families. Glycosyl hydrolases (GH) are the most abundant group, being represented in larger quantities by GH3, 5, 17, 43, and 72. Cellobiohydrolases, endoglucanases, β-glycosidases, xylanases, β-xylosidases, and mannanases were found, and in minor quantities, pectinases, ligninases, and amylases were also found. Swollenin and esterases were also identified. CONCLUSIONS Our study revealed differences in the two strains of P. echinulatum in several aspects in which the mutation improved the production of enzymes related to lignocellulosic biomass deconstruction. Considering the spectral counting analysis, the mutant strain S1M29 was more efficient in the production of enzymes involved in cellulose and hemicellulose degradation, despite having a nearly identical CAZy enzymatic repertoire. Moreover, S1M29 secretes more quantities of protein on SCB than on cellulose, relevant information when considering the production of cellulases using raw materials at low cost. Glucose, and especially glycerol, were used mainly for the production of amylases and ligninases.
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Affiliation(s)
- Willian Daniel Hahn Schneider
- />Enzymes and Biomass Laboratory, Institute of Biotechnology, University of Caxias do Sul, Francisco Getúlio Vargas Street 1130, Caxias Do Sul, RS 95070-560 Brazil
| | - Thiago Augusto Gonçalves
- />Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Giuseppe Maximo Scolfaro 10.000, Campinas, São Paulo 13083-970 Brazil
- />Department of Biochemistry, Institute of Biology, State University of Campinas (UNICAMP), Campinas, São Paulo Brazil
| | - Cristiane Akemi Uchima
- />Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Giuseppe Maximo Scolfaro 10.000, Campinas, São Paulo 13083-970 Brazil
| | - Matthew Brian Couger
- />Department of Microbiology and Molecular Genetics, Oklahoma State University, 1110 South Innovation Way, Stillwater, OK 74078 USA
| | - Rolf Prade
- />Department of Microbiology and Molecular Genetics, Oklahoma State University, 1110 South Innovation Way, Stillwater, OK 74078 USA
| | - Fabio Marcio Squina
- />Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Giuseppe Maximo Scolfaro 10.000, Campinas, São Paulo 13083-970 Brazil
| | - Aldo José Pinheiro Dillon
- />Enzymes and Biomass Laboratory, Institute of Biotechnology, University of Caxias do Sul, Francisco Getúlio Vargas Street 1130, Caxias Do Sul, RS 95070-560 Brazil
| | - Marli Camassola
- />Enzymes and Biomass Laboratory, Institute of Biotechnology, University of Caxias do Sul, Francisco Getúlio Vargas Street 1130, Caxias Do Sul, RS 95070-560 Brazil
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Kaupert Neto AA, Borin GP, Goldman GH, Damásio ARDL, Oliveira JVDC. Insights into the plant polysaccharide degradation potential of the xylanolytic yeast Pseudozyma brasiliensis. FEMS Yeast Res 2015; 16:fov117. [PMID: 26712719 DOI: 10.1093/femsyr/fov117] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2015] [Indexed: 12/13/2022] Open
Abstract
In second-generation (2G) bioethanol production, plant cell-wall polysaccharides are broken down to release fermentable sugars. The enzymes of this process are classified as carbohydrate-active enzymes (CAZymes) and contribute substantially to the cost of biofuel production. A novel basidiomycete yeast species, Pseudozyma brasiliensis, was recently discovered. It produces an endo-β-1,4-xylanase with a higher specific activity than other xylanases. This enzyme is essential for the hydrolysis of biomass-derived xylan and has an important role in 2G bioethanol production. In spite of the P. brasiliensis biotechnological potential, there is no information about how it breaks down polysaccharides. For the first time, we characterized the secretome of P. brasiliensis grown on different carbon sources (xylose, xylan, cellobiose and glucose) and also under starvation conditions. The growth and consumption of each carbohydrate and the activity of the CAZymes of culture supernatants were analyzed. The CAZymes found in its secretomes, validated by enzymatic assays, have the potential to hydrolyze xylan, mannan, cellobiose and other polysaccharides. The data show that this yeast is a potential source of hydrolases, which can be used for biomass saccharification.
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Affiliation(s)
- Antonio Adalberto Kaupert Neto
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Caixa Postal 6192, CEP 13083-970, Campinas, São Paulo, Brasil
| | - 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, Caixa Postal 6192, CEP 13083-970, Campinas, São Paulo, Brasil
| | - Gustavo Henrique Goldman
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Caixa Postal 6192, CEP 13083-970, Campinas, São Paulo, Brasil Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av do Café S/N, CEP 14040-903, Ribeirão Preto, São Paulo, Brasil
| | - André Ricardo de Lima Damásio
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Av Giuseppe Maximo Scolfaro 10000, Caixa Postal 6192, CEP 13083-970, Campinas, São Paulo, Brasil Departamento de Bioquímica e Biologia Tecidual, Instituto de Biologia, Universidade de Campinas, Rua Monteiro Lobato, 255, Caixa Postal 6109, CEP 13083-970, São Paulo, Brasil
| | - 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, Caixa Postal 6192, CEP 13083-970, Campinas, São Paulo, Brasil
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Sharma B, Agrawal R, Singhania RR, Satlewal A, Mathur A, Tuli D, Adsul M. Untreated wheat straw: potential source for diverse cellulolytic enzyme secretion by Penicillium janthinellum EMS-UV-8 mutant. BIORESOURCE TECHNOLOGY 2015; 196:518-24. [PMID: 26291411 DOI: 10.1016/j.biortech.2015.08.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 08/06/2015] [Accepted: 08/08/2015] [Indexed: 05/18/2023]
Abstract
Study describes the production of cellulases by Penicillium janthinellum EMS-UV-8 using untreated wheat straw (WS), treated WS (acid, alkali, steam exploded, organo-solv) and pure cellulosic substrates (avicel, cellulose-II and carboxymethyl cellulose). Severely pretreated WS and cellulose-II produced more cellulolytic enzymes than untreated samples. XRD and FTIR analysis revels that the increase in the amorphous structure of pretreated WS/cellulose increases enzyme production. Enzyme samples prepared using different substrates were used for the hydrolysis of dilute acid treated wheat straw (DATWS), steam exploded wheat straw (SEWS) and avicel. The enzyme prepared using untreated WS gave more hydrolysis of DATWS and SEWS than the enzyme prepared using pretreated WS or pure cellulosic substrates. This revels that more diverse/potential enzymes were secreted by P. janthinellum EMS-UV-8 mutant using untreated WS. This study may contribute in production of efficient enzyme mixture/cocktail by single fungal strain for economic conversion of biomass to sugars.
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Affiliation(s)
- Bhawna Sharma
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Ruchi Agrawal
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Reeta Rani Singhania
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Alok Satlewal
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Anshu Mathur
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Deepak Tuli
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Mukund Adsul
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India.
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Comparative Secretome Analysis of Aspergillus niger, Trichoderma reesei, and Penicillium oxalicum During Solid-State Fermentation. Appl Biochem Biotechnol 2015; 177:1252-71. [DOI: 10.1007/s12010-015-1811-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 08/17/2015] [Indexed: 10/23/2022]
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Ogunmolu FE, Kaur I, Gupta M, Bashir Z, Pasari N, Yazdani SS. Proteomics Insights into the Biomass Hydrolysis Potentials of a Hypercellulolytic Fungus Penicillium funiculosum. J Proteome Res 2015; 14:4342-58. [PMID: 26288988 DOI: 10.1021/acs.jproteome.5b00542] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The quest for cheaper and better enzymes needed for the efficient hydrolysis of lignocellulosic biomass has placed filamentous fungi in the limelight for bioprospecting research. In our search for efficient biomass degraders, we identified a strain of Penicillium funiculosum whose secretome demonstrates high saccharification capabilities. Our probe into the secretome of the fungus through qualitative and label-free quantitative mass spectrometry based proteomics studies revealed a high abundance of inducible CAZymes and several nonhydrolytic accessory proteins. The preferential association of these proteins and the attending differential biomass hydrolysis gives an insight into their interactions and clues about possible roles of novel hydrolytic and nonhydrolytic proteins in the synergistic deconstruction of lignocellulosic biomass. Our study thus provides the first comprehensive insight into the repertoire of proteins present in a high-performing secretome of a hypercellulolytic Penicillium funiculosum, their relative abundance in the secretome, and the interaction dynamics of the various protein groups in the secretome. The gleanings from the stoichiometry of these interactions hold a prospect as templates in the design of cost-effective synthetic cocktails for the optimal hydrolysis of biomass.
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Affiliation(s)
- Funso Emmanuel Ogunmolu
- Synthetic Biology and Biofuels Group, ‡Malaria Group, and §DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, 110 067 New Delhi, India
| | - Inderjeet Kaur
- Synthetic Biology and Biofuels Group, ‡Malaria Group, and §DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, 110 067 New Delhi, India
| | - Mayank Gupta
- Synthetic Biology and Biofuels Group, ‡Malaria Group, and §DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, 110 067 New Delhi, India
| | - Zeenat Bashir
- Synthetic Biology and Biofuels Group, ‡Malaria Group, and §DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, 110 067 New Delhi, India
| | - Nandita Pasari
- Synthetic Biology and Biofuels Group, ‡Malaria Group, and §DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, 110 067 New Delhi, India
| | - Syed Shams Yazdani
- Synthetic Biology and Biofuels Group, ‡Malaria Group, and §DBT-ICGEB Centre for Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, 110 067 New Delhi, India
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Isolation of Fungi and Bacteria Associated with the Guts of Tropical Wood-Feeding Coleoptera and Determination of Their Lignocellulolytic Activities. Int J Microbiol 2015; 2015:285018. [PMID: 26379709 PMCID: PMC4563095 DOI: 10.1155/2015/285018] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 08/12/2015] [Indexed: 12/22/2022] Open
Abstract
The guts of beetle larvae constitute a complex system where relationships among fungi, bacteria, and the insect host occur. In this study, we collected larvae of five families of wood-feeding Coleoptera in tropical forests of Costa Rica, isolated fungi and bacteria from their intestinal tracts, and determined the presence of five different pathways for lignocellulolytic activity. The fungal isolates were assigned to three phyla, 16 orders, 24 families, and 40 genera; Trichoderma was the most abundant genus, detected in all insect families and at all sites. The bacterial isolates were assigned to five phyla, 13 orders, 22 families, and 35 genera; Bacillus, Serratia, and Pseudomonas were the dominant genera, present in all the Coleopteran families. Positive results for activities related to degradation of wood components were determined in 65% and 48% of the fungal and bacterial genera, respectively. Our results showed that both the fungal and bacterial populations were highly diverse in terms of number of species and their phylogenetic composition, although the structure of the microbial communities varied with insect host family and the surrounding environment. The recurrent identification of some lignocellulolytic-positive inhabitants suggests that particular microbial groups play important roles in providing nutritional needs for the Coleopteran host.
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Abstract
SUMMARY Biomass is constructed of dense recalcitrant polymeric materials: proteins, lignin, and holocellulose, a fraction constituting fibrous cellulose wrapped in hemicellulose-pectin. Bacteria and fungi are abundant in soil and forest floors, actively recycling biomass mainly by extracting sugars from holocellulose degradation. Here we review the genome-wide contents of seven Aspergillus species and unravel hundreds of gene models encoding holocellulose-degrading enzymes. Numerous apparent gene duplications followed functional evolution, grouping similar genes into smaller coherent functional families according to specialized structural features, domain organization, biochemical activity, and genus genome distribution. Aspergilli contain about 37 cellulase gene models, clustered in two mechanistic categories: 27 hydrolyze and 10 oxidize glycosidic bonds. Within the oxidative enzymes, we found two cellobiose dehydrogenases that produce oxygen radicals utilized by eight lytic polysaccharide monooxygenases that oxidize glycosidic linkages, breaking crystalline cellulose chains and making them accessible to hydrolytic enzymes. Among the hydrolases, six cellobiohydrolases with a tunnel-like structural fold embrace single crystalline cellulose chains and cooperate at nonreducing or reducing end termini, splitting off cellobiose. Five endoglucanases group into four structural families and interact randomly and internally with cellulose through an open cleft catalytic domain, and finally, seven extracellular β-glucosidases cleave cellobiose and related oligomers into glucose. Aspergilli contain, on average, 30 hemicellulase and 7 accessory gene models, distributed among 9 distinct functional categories: the backbone-attacking enzymes xylanase, mannosidase, arabinase, and xyloglucanase, the short-side-chain-removing enzymes xylan α-1,2-glucuronidase, arabinofuranosidase, and xylosidase, and the accessory enzymes acetyl xylan and feruloyl esterases.
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Shrestha P, Ibáñez AB, Bauer S, Glassman SI, Szaro TM, Bruns TD, Taylor JW. Fungi isolated from Miscanthus and sugarcane: biomass conversion, fungal enzymes, and hydrolysis of plant cell wall polymers. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:38. [PMID: 25784958 PMCID: PMC4362644 DOI: 10.1186/s13068-015-0221-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 02/04/2015] [Indexed: 05/26/2023]
Abstract
BACKGROUND Biofuel use is one of many means of addressing global change caused by anthropogenic release of fossil fuel carbon dioxide into Earth's atmosphere. To make a meaningful reduction in fossil fuel use, bioethanol must be produced from the entire plant rather than only its starch or sugars. Enzymes produced by fungi constitute a significant percentage of the cost of bioethanol production from non-starch (i.e., lignocellulosic) components of energy crops and agricultural residues. We, and others, have reasoned that fungi that naturally deconstruct plant walls may provide the best enzymes for bioconversion of energy crops. RESULTS Previously, we have reported on the isolation of 106 fungi from decaying leaves of Miscanthus and sugarcane (Appl Environ Microbiol 77:5490-504, 2011). Here, we thoroughly analyze 30 of these fungi including those most often found on decaying leaves and stems of these plants, as well as four fungi chosen because they are well-studied for their plant cell wall deconstructing enzymes, for wood decay, or for genetic regulation of plant cell wall deconstruction. We extend our analysis to assess not only their ability over an 8-week period to bioconvert Miscanthus cell walls but also their ability to secrete total protein, to secrete enzymes with the activities of xylanases, exocellulases, endocellulases, and beta-glucosidases, and to remove specific parts of Miscanthus cell walls, that is, glucan, xylan, arabinan, and lignin. CONCLUSION This study of fungi that bioconvert energy crops is significant because 30 fungi were studied, because the fungi were isolated from decaying energy grasses, because enzyme activity and removal of plant cell wall components were recorded in addition to biomass conversion, and because the study period was 2 months. Each of these factors make our study the most thorough to date, and we discovered fungi that are significantly superior on all counts to the most widely used, industrial bioconversion fungus, Trichoderma reesei. Many of the best fungi that we found are in taxonomic groups that have not been exploited for industrial bioconversion and the cultures are available from the Centraalbureau voor Schimmelcultures in Utrecht, Netherlands, for all to use.
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Affiliation(s)
- Prachand Shrestha
- />Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3102 USA
| | - Ana B Ibáñez
- />Energy Biosciences Institute, University of California, Berkeley, CA 94720 USA
| | - Stefan Bauer
- />Energy Biosciences Institute, University of California, Berkeley, CA 94720 USA
| | - Sydney I Glassman
- />Department of Environmental Science Policy and Management, University of California, Berkeley, CA 94720 USA
| | - Timothy M Szaro
- />Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3102 USA
| | - Thomas D Bruns
- />Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3102 USA
| | - John W Taylor
- />Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3102 USA
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Winger AM, Heazlewood JL, Chan LJG, Petzold CJ, Permaul K, Singh S. Secretome analysis of the thermophilic xylanase hyper-producer Thermomyces lanuginosus SSBP cultivated on corn cobs. J Ind Microbiol Biotechnol 2014; 41:1687-96. [PMID: 25223615 DOI: 10.1007/s10295-014-1509-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 09/03/2014] [Indexed: 12/27/2022]
Abstract
Thermomyces lanuginosus is a thermophilic fungus known for its ability to produce industrially important enzymes including large amounts of xylanase, the key enzyme in hemicellulose hydrolysis. The secretome of T. lanuginosus SSBP was profiled by shotgun proteomics to elucidate important enzymes involved in hemicellulose saccharification and to characterise the presence of other industrially interesting enzymes. This study reproducibly identified a total of 74 proteins in the supernatant following growth on corn cobs. An analysis of proteins revealed nine glycoside hydrolase (GH) enzymes including xylanase GH11, β-xylosidase GH43, β-glucosidase GH3, α-galactosidase GH36 and trehalose hydrolase GH65. Two commercially produced Thermomyces enzymes, lipase and amylase, were also identified. In addition, other industrially relevant enzymes not currently explored in Thermomyces were identified including glutaminase, fructose-bisphosphate aldolase and cyanate hydratase. Overall, these data provide insight into the novel ability of a cellulase-free fungus to utilise lignocellulosic material, ultimately producing a number of enzymes important to various industrial processes.
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Affiliation(s)
- A M Winger
- Department of Biotechnology and Food Technology, Durban University of Technology, Durban, 4001, South Africa
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van den Brink J, Maitan-Alfenas GP, Zou G, Wang C, Zhou Z, Guimarães VM, de Vries RP. Synergistic effect ofAspergillus nigerandTrichoderma reeseienzyme sets on the saccharification of wheat straw and sugarcane bagasse. Biotechnol J 2014; 9:1329-38. [DOI: 10.1002/biot.201400317] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 07/09/2014] [Accepted: 08/12/2014] [Indexed: 01/06/2023]
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Karnaouri A, Topakas E, Antonopoulou I, Christakopoulos P. Genomic insights into the fungal lignocellulolytic system of Myceliophthora thermophila. Front Microbiol 2014; 5:281. [PMID: 24995002 PMCID: PMC4061905 DOI: 10.3389/fmicb.2014.00281] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 05/22/2014] [Indexed: 01/08/2023] Open
Abstract
The microbial conversion of solid cellulosic biomass to liquid biofuels may provide a renewable energy source for transportation fuels. Cellulolytic fungi represent a promising group of organisms, as they have evolved complex systems for adaptation to their natural habitat. The filamentous fungus Myceliophthora thermophila constitutes an exceptionally powerful cellulolytic microorganism that synthesizes a complete set of enzymes necessary for the breakdown of plant cell wall. The genome of this fungus has been recently sequenced and annotated, allowing systematic examination and identification of enzymes required for the degradation of lignocellulosic biomass. The genomic analysis revealed the existence of an expanded enzymatic repertoire including numerous cellulases, hemicellulases, and enzymes with auxiliary activities, covering the most of the recognized CAZy families. Most of them were predicted to possess a secretion signal and undergo through post-translational glycosylation modifications. These data offer a better understanding of activities embedded in fungal lignocellulose decomposition mechanisms and suggest that M. thermophila could be made usable as an industrial production host for cellulolytic and hemicellulolytic enzymes.
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Affiliation(s)
- Anthi Karnaouri
- Biotechnology Laboratory, Department of Synthesis and Development of Industrial Processes, School of Chemical Engineering, National Technical University of Athens Athens, Greece ; Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Evangelos Topakas
- Biotechnology Laboratory, Department of Synthesis and Development of Industrial Processes, School of Chemical Engineering, National Technical University of Athens Athens, Greece
| | - Io Antonopoulou
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
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Siguier B, Haon M, Nahoum V, Marcellin M, Burlet-Schiltz O, Coutinho PM, Henrissat B, Mourey L, O'Donohue MJ, Berrin JG, Tranier S, Dumon C. First structural insights into α-L-arabinofuranosidases from the two GH62 glycoside hydrolase subfamilies. J Biol Chem 2014; 289:5261-73. [PMID: 24394409 DOI: 10.1074/jbc.m113.528133] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
α-L-arabinofuranosidases are glycoside hydrolases that specifically hydrolyze non-reducing residues from arabinose-containing polysaccharides. In the case of arabinoxylans, which are the main components of hemicellulose, they are part of microbial xylanolytic systems and are necessary for complete breakdown of arabinoxylans. Glycoside hydrolase family 62 (GH62) is currently a small family of α-L-arabinofuranosidases that contains only bacterial and fungal members. Little is known about the GH62 mechanism of action, because only a few members have been biochemically characterized and no three-dimensional structure is available. Here, we present the first crystal structures of two fungal GH62 α-L-arabinofuranosidases from the basidiomycete Ustilago maydis (UmAbf62A) and ascomycete Podospora anserina (PaAbf62A). Both enzymes are able to efficiently remove the α-L-arabinosyl substituents from arabinoxylan. The overall three-dimensional structure of UmAbf62A and PaAbf62A reveals a five-bladed β-propeller fold that confirms their predicted classification into clan GH-F together with GH43 α-L-arabinofuranosidases. Crystallographic structures of the complexes with arabinose and cellotriose reveal the important role of subsites +1 and +2 for sugar binding. Intriguingly, we observed that PaAbf62A was inhibited by cello-oligosaccharides and displayed binding affinity to cellulose although no activity was observed on a range of cellulosic substrates. Bioinformatic analyses showed that UmAbf62A and PaAbf62A belong to two distinct subfamilies within the GH62 family. The results presented here provide a framework to better investigate the structure-function relationships within the GH62 family.
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Affiliation(s)
- Béatrice Siguier
- From the Université de Toulouse, INSA, UPS, INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse
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Marx IJ, van Wyk N, Smit S, Jacobson D, Viljoen-Bloom M, Volschenk H. Comparative secretome analysis of Trichoderma asperellum S4F8 and Trichoderma reesei Rut C30 during solid-state fermentation on sugarcane bagasse. BIOTECHNOLOGY FOR BIOFUELS 2013; 6:172. [PMID: 24286470 PMCID: PMC4177139 DOI: 10.1186/1754-6834-6-172] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2013] [Accepted: 10/22/2013] [Indexed: 05/05/2023]
Abstract
BACKGROUND The lignocellulosic enzymes of Trichoderma species have received particular attention with regard to biomass conversion to biofuels, but the production cost of these enzymes remains a significant hurdle for their commercial application. In this study, we quantitatively compared the lignocellulolytic enzyme profile of a newly isolated Trichoderma asperellum S4F8 strain with that of Trichoderma reesei Rut C30, cultured on sugarcane bagasse (SCB) using solid-state fermentation (SSF). RESULTS Comparison of the lignocellulolytic enzyme profiles of S4F8 and Rut C30 showed that S4F8 had significantly higher hemicellulase and β-glucosidase enzyme activities. Liquid chromatography tandem mass spectrometry analysis of the two fungal secretomes enabled the detection of 815 proteins in total, with 418 and 397 proteins being specific for S4F8 and Rut C30, respectively, and 174 proteins being common to both strains. In-depth analysis of the associated biological functions and the representation of glycoside hydrolase family members within the two secretomes indicated that the S4F8 secretome contained a higher diversity of main and side chain hemicellulases and β-glucosidases, and an increased abundance of some of these proteins compared with the Rut C30 secretome. CONCLUSIONS In SCB SSF, T. asperellum S4F8 produced a more complex lignocellulolytic cocktail, with enhanced hemicellulose and cellobiose hydrolysis potential, compared with T. reesei Rut C30. This bodes well for the development of a more cost-effective and efficient lignocellulolytic enzyme cocktail from T. asperellum for lignocellulosic feedstock hydrolysis.
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Affiliation(s)
- Isa Jacoba Marx
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland 7602, Stellenbosch, South Africa
| | - Niël van Wyk
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland 7602, Stellenbosch, South Africa
| | - Salome Smit
- MS Unit, Proteomics Laboratory, Central Analytical Facility, Stellenbosch University, Private Bag X1, Matieland 7602, Stellenbosch, South Africa
- Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Francie van Zijl Drive, PO Box 19063, Tygerberg 7505, South Africa
| | - Daniel Jacobson
- Institute for Wine Biotechnology, Faculty of AgriSciences, Stellenbosch University, Private Bag X1, 7602, Matieland, South Africa
| | - Marinda Viljoen-Bloom
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland 7602, Stellenbosch, South Africa
| | - Heinrich Volschenk
- Department of Microbiology, Stellenbosch University, Private Bag X1, Matieland 7602, Stellenbosch, South Africa
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Cairo JPLF, Oliveira LC, Uchima CA, Alvarez TM, Citadini APDS, Cota J, Leonardo FC, Costa-Leonardo AM, Carazzolle MF, Costa FF, Pereira GAG, Squina FM. Deciphering the synergism of endogenous glycoside hydrolase families 1 and 9 from Coptotermes gestroi. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2013; 43:970-81. [PMID: 23917163 DOI: 10.1016/j.ibmb.2013.07.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 07/24/2013] [Accepted: 07/25/2013] [Indexed: 05/23/2023]
Abstract
Termites can degrade up to 90% of the lignocellulose they ingest using a repertoire of endogenous and symbiotic degrading enzymes. Termites have been shown to secrete two main glycoside hydrolases, which are GH1 (EC 3.2.1.21) and GH9 (EC 3.2.1.4) members. However, the molecular mechanism for lignocellulose degradation by these enzymes remains poorly understood. The present study was conducted to understand the synergistic relationship between GH9 (CgEG1) and GH1 (CgBG1) from Coptotermes gestroi, which is considered the major urban pest of São Paulo State in Brazil. The goal of this work was to decipher the mode of operation of CgEG1 and CgBG1 through a comprehensive biochemical analysis and molecular docking studies. There was outstanding degree of synergy in degrading glucose polymers for the production of glucose as a result of the endo-β-1,4-glucosidase and exo-β-1,4-glucosidase degradation capability of CgEG1 in concert with the high catalytic performance of CgBG1, which rapidly converts the oligomers into glucose. Our data not only provide an increased comprehension regarding the synergistic mechanism of these two enzymes for cellulose saccharification but also give insight about the role of these two enzymes in termite biology, which can provide the foundation for the development of a number of important applied research topics, such as the control of termites as pests as well as the development of technologies for lignocellulose-to-bioproduct applications.
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Affiliation(s)
- João Paulo L Franco Cairo
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Rua Giuseppe Máximo Scolfaro, nº 10000, 13083-970 Campinas, SP, Brazil; Laboratório de Genômica e Expressão (LGE), Departamento de Genética, Evolução e Bioagentes da Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
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44
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Wu M, Bu L, Vuong TV, Wilson DB, Crowley MF, Sandgren M, Ståhlberg J, Beckham GT, Hansson H. Loop motions important to product expulsion in the Thermobifida fusca glycoside hydrolase family 6 cellobiohydrolase from structural and computational studies. J Biol Chem 2013; 288:33107-17. [PMID: 24085303 DOI: 10.1074/jbc.m113.502765] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cellobiohydrolases (CBHs) are typically major components of natural enzyme cocktails for biomass degradation. Their active sites are enclosed in a tunnel, enabling processive hydrolysis of cellulose chains. Glycoside hydrolase Family 6 (GH6) CBHs act from nonreducing ends by an inverting mechanism and are present in many cellulolytic fungi and bacteria. The bacterial Thermobifida fusca Cel6B (TfuCel6B) exhibits a longer and more enclosed active site tunnel than its fungal counterparts. Here, we determine the structures of two TfuCel6B mutants co-crystallized with cellobiose, D274A (catalytic acid), and the double mutant D226A/S232A, which targets the putative catalytic base and a conserved serine that binds the nucleophilic water. The ligand binding and the structure of the active site are retained when compared with the wild type structure, supporting the hypothesis that these residues are directly involved in catalysis. One structure exhibits crystallographic waters that enable construction of a model of the α-anomer product after hydrolysis. Interestingly, the product sites of TfuCel6B are completely enclosed by an "exit loop" not present in fungal GH6 CBHs and by an extended "bottom loop". From the structures, we hypothesize that either of the loops enclosing the product subsites in the TfuCel6B active site tunnel must open substantially for product release. With simulation, we demonstrate that both loops can readily open to allow product release with equal probability in solution or when the enzyme is engaged on cellulose. Overall, this study reveals new structural details of GH6 CBHs likely important for functional differences among enzymes from this important family.
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Affiliation(s)
- Miao Wu
- From the Department of Molecular Biology, Swedish University of Agricultural Sciences, SE-75007 Uppsala, Sweden
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Salvachúa D, Martínez AT, Tien M, López-Lucendo MF, García F, de los Ríos V, Martínez MJ, Prieto A. Differential proteomic analysis of the secretome of Irpex lacteus and other white-rot fungi during wheat straw pretreatment. BIOTECHNOLOGY FOR BIOFUELS 2013; 6:115. [PMID: 23937687 PMCID: PMC3750859 DOI: 10.1186/1754-6834-6-115] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 08/06/2013] [Indexed: 05/06/2023]
Abstract
BACKGROUND Identifying new high-performance enzymes or enzyme complexes to enhance biomass degradation is the key for the development of cost-effective processes for ethanol production. Irpex lacteus is an efficient microorganism for wheat straw pretreatment, yielding easily hydrolysable products with high sugar content. Thus, this fungus was selected to investigate the enzymatic system involved in lignocellulose decay, and its secretome was compared to those from Phanerochaete chrysosporium and Pleurotus ostreatus which produced different degradation patterns when growing on wheat straw. Extracellular enzymes were analyzed through 2D-PAGE, nanoLC/MS-MS, and homology searches against public databases. RESULTS In wheat straw, I. lacteus secreted proteases, dye-decolorizing and manganese-oxidizing peroxidases, and H2O2 producing-enzymes but also a battery of cellulases and xylanases, excluding those implicated in cellulose and hemicellulose degradation to their monosaccharides, making these sugars poorly available for fungal consumption. In contrast, a significant increase of β-glucosidase production was observed when I. lacteus grew in liquid cultures. P. chrysosporium secreted more enzymes implicated in the total hydrolysis of the polysaccharides and P. ostreatus produced, in proportion, more oxidoreductases. CONCLUSION The protein pattern secreted during I. lacteus growth in wheat straw plus the differences observed among the different secretomes, justify the fitness of I. lacteus for biopretreatment processes in 2G-ethanol production. Furthermore, all these data give insight into the biological degradation of lignocellulose and suggest new enzyme mixtures interesting for its efficient hydrolysis.
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Affiliation(s)
- Davinia Salvachúa
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | - Angel T Martínez
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | - Ming Tien
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park PA, 16802 USA
| | - María F López-Lucendo
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | - Francisco García
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | - Vivian de los Ríos
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | - María Jesús Martínez
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain
| | - Alicia Prieto
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain
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Valencia EY, Chambergo FS. Mini-review: Brazilian fungi diversity for biomass degradation. Fungal Genet Biol 2013; 60:9-18. [PMID: 23872076 DOI: 10.1016/j.fgb.2013.07.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 06/28/2013] [Accepted: 07/08/2013] [Indexed: 01/01/2023]
Abstract
Brazil houses over 10% of the total number of known species on Earth, with a great diversity of plants and fungi. The collection, isolation, identification and conservation of filamentous fungi with relevance to agriculture, pharmaceutical, food and biotechnological industries in Biological Resource Centers (CRBs) is very important to the development of a nation's scientific and technological infrastructure. In Brazil, 36 fungal collections are registered in the database of International Collections. Several federal and state programs have encouraged the formation of a researcher's network in order to study natural resources and the nation's biodiversity. In this context, Brazilian researchers have been on the frontiers of knowledge, investigating the enzymatic systems from native filamentous fungi with potential for biomass degradation and biotechnological application. In this review, we address recent progress in Brazilian fungal research, focusing on the identification and study of fungi and enzymes with potential for biomass degradation and application in bioenergy.
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Affiliation(s)
- Estela Y Valencia
- Departamento de Microbiologia Microbiana, Centro Nacional de Biotecnologia (CSIC), Madrid, Spain.
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Liu G, Qin Y, Li Z, Qu Y. Development of highly efficient, low-cost lignocellulolytic enzyme systems in the post-genomic era. Biotechnol Adv 2013; 31:962-75. [PMID: 23507038 DOI: 10.1016/j.biotechadv.2013.03.001] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 03/09/2013] [Accepted: 03/10/2013] [Indexed: 11/19/2022]
Abstract
The current high cost of lignocellulolytic enzymes is a major bottleneck in the economic bioconversion of lignocellulosic biomass to fuels and chemicals. Fungal lignocellulolytic enzyme systems are secreted at high levels, making them the most promising starting points for further development of highly efficient lignocellulolytic enzyme systems. In this paper, recent advances in improvement of fungal lignocellulolytic enzyme systems are reviewed, with an emphasis on the achievements made using genomic approaches. A general strategy for lignocellulolytic enzyme system development is proposed, including the improvement of the hydrolysis efficiencies and productivities of current enzyme systems. The applications of genomic, transcriptomic and proteomic analysis methods in examining the composition of native enzyme systems, discovery of novel enzymes and synergistic proteins from natural sources, and understanding of regulatory mechanisms for lignocellulolytic enzyme biosynthesis are summarized. By combining systems biology and synthetic biology tools, engineered fungal strains are expected to produce high levels of optimized lignocellulolytic enzyme systems.
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Affiliation(s)
- Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China
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