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Nabi F, Chen H, Sajid S, Yang G, Kyung Y, Shah SMM, Wang X, Hu Y. Degradation of agricultural waste is dependent on chemical fertilizers in long-term paddy-dry rotation field. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 355:120460. [PMID: 38430881 DOI: 10.1016/j.jenvman.2024.120460] [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: 09/21/2023] [Revised: 01/25/2024] [Accepted: 02/20/2024] [Indexed: 03/05/2024]
Abstract
The practice of returning straw to agricultural fields is a globally employed technique. Such agricultural fields also receive a significant amount of nitrogen (N) and phosphorus (P) fertilizers, because these two macronutrients are essential for plant growth and development. However, the consequences of such macronutrients input on straw decomposition, soil dissolved organic matter (DOM), key microbes, and lignocellulolytic enzymes are still unclear. In a similar aim, we designed a long-term straw returning study without and with different N and P nutrient supplementation: CK (N0P0), T1 (N120P0), T2 (N120P60), T3 (N120P90), T4 (N120P120), T5 (N0P90), T6 (N60P90), and T7 (N180P90), and evaluated their impact on rice and oilseed rape yield, soil DOM, enzymes, lignocellulose content, microbial diversity, and composition. We found straw returning improved overall yield in all treatments and T7 showed the highest yield for oilseed rape (30.31-38.87 g/plant) and rice (9.14-9.91 t/ha) during five-years of study. The fertilizer application showed a significant impact on soil physicochemical properties, such as water holding capacity and soil porosity decreased, and bulk density increased in fertilized treatments, as compared to CK. Similarly, significantly low OM, cellulose, hemicellulose, and lignin content were found in T7, T4, T3, and T2, while high values were found in CK and T5, respectively. The fluorescence excitation-emission matrix spectra of DOM of different treatments revealed that T3, T7, T4, and T6 showed high peak M (microbial by-products), peak A and peak C (humic acid-like) as compared to others. The microbial composition was also distinctive in each treatment and a high relative abundance of Chloroflexi, Actinobacteriota, Ascomycota, and Basidiomycota were found in T2 and T3 treatments, respectively. These findings indicate that the decomposition of straw in the agricultural field was dependent on nutrients input, which facilitated key microbial growth and impacted positively on lignocellulolytic enzymes, which further aided the breakdown of all components of straw in the field efficiently. On the other hand, high input of chemical based fertilizers to soil can lead to several environmental issues, such as nutrient imbalance, nutrient runoff, soil pH change and changes in microbial activities. Keeping that in consideration, we recommend moderate fertilizer dosage (N120P90) in such fields to achieve higher decomposition of crop straw with a small yield compromise.
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Affiliation(s)
- Farhan Nabi
- College of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, 621010, China; College of Nature Resources and Environment, South China Agricultural University, Guangzhou, Guangdong, 510642, China
| | - Hong Chen
- College of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, 621010, China
| | - Sumbal Sajid
- College of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, 621010, China; Shenzhen Institute of Guangdong Ocean University, Binhai 2nd Road, Shenzhen, 518120, China
| | - Guotao Yang
- College of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, 621010, China
| | - Yun Kyung
- Department of Environment and Energy, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, South Korea; Department of Environmental Engineering and Earth Science, Clemson University, SC, 29634, USA
| | - Syed Muhammad Mustajab Shah
- College of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, 621010, China
| | - Xuechun Wang
- College of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, 621010, China.
| | - Yungao Hu
- College of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan, 621010, China.
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Liu J, Chen M, Gu S, Fan R, Zhao Z, Sun W, Yao Y, Li J, Tian C. Independent metabolism of oligosaccharides is the keystone of synchronous utilization of cellulose and hemicellulose in Myceliophthora. PNAS NEXUS 2024; 3:pgae053. [PMID: 38380057 PMCID: PMC10877092 DOI: 10.1093/pnasnexus/pgae053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 01/29/2024] [Indexed: 02/22/2024]
Abstract
The effective utilization of cellulose and hemicellulose, the main components of plant biomass, is a key technical obstacle that needs to be overcome for the economic viability of lignocellulosic biorefineries. Here, we firstly demonstrated that the thermophilic cellulolytic fungus Myceliophthora thermophila can simultaneously utilize cellulose and hemicellulose, as evidenced by the independent uptake and intracellular metabolism of cellodextrin and xylodextrin. When plant biomass serviced as carbon source, we detected the cellodextrin and xylodextrin both in cells and in the culture medium, as well as high enzyme activities related to extracellular oligosaccharide formation and intracellular oligosaccharide hydrolysis. Sugar consumption assay revealed that in contrast to inhibitory effect of glucose on xylose and cellodextrin/xylodextrin consumption in mixed-carbon media, cellodextrin and xylodextrin were synchronously utilized in this fungus. Transcriptomic analysis also indicated simultaneous induction of the genes involved in cellodextrin and xylodextrin metabolic pathway, suggesting carbon catabolite repression (CCR) is triggered by extracellular glucose and can be eliminated by the intracellular hydrolysis and metabolism of oligosaccharides. The xylodextrin transporter MtCDT-2 was observed to preferentially transport xylobiose and tolerate high cellobiose concentrations, which helps to bypass the inhibition of xylobiose uptake. Furthermore, the expression of cellulase and hemicellulase genes was independently induced by their corresponding inducers, which enabled this strain to synchronously utilize cellulose and hemicellulose. Taken together, the data presented herein will further elucidate the degradation of plant biomass by fungi, with implications for the development of consolidated bioprocessing-based lignocellulosic biorefinery.
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Affiliation(s)
- Jia Liu
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Meixin Chen
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Shuying Gu
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Rui Fan
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Zhen Zhao
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Wenliang Sun
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Yonghong Yao
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Jingen Li
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Chaoguang Tian
- Key Laboratory of Engineering Biology for Low-carbon Manufacturing, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
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Lan J, Zhang L, Gao J, He R. TrLys9 participates in fungal development and lysine biosynthesis in Trichoderma reesei. J GEN APPL MICROBIOL 2023; 69:159-166. [PMID: 36805586 DOI: 10.2323/jgam.2023.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Fungi uniquely synthesize lysine through the α-aminoadipate pathway. The saccharopine reductase ScLys9 catalyzes the formation of saccharopine from ɑ-aminoadipate 6-semialdehyde, the seventh step in the lysine biosynthesis pathway in Saccharomyces cerevisiae. Here, we characterized the functions of TrLys9, an ortholog of S. cerevisiae ScLys9 in the industrial filamentous fungus Trichoderma reesei. Transcriptional level analysis indicated that TrLYS9 expression was higher in the conidial stage than in other stages. Disruption of TrLYS9 led to lysine auxotrophy. Phenotype analysis of the ΔTrlys9 mutant showed that TrLYS9 was involved in fungal development including vegetative growth, conidiation, and conidial germination and lysine biosynthesis. Cellulase production was also impaired in the ΔTrlys9 mutant due to the failure of conidial germination in liquid cellulase-inducing medium. Defects in radial growth and asexual development of the ΔTrlys9 mutant were fully recovered when exogenous lysine was added to the medium. These results imply that TrLys9 is involved in fungal development and lysine biosynthesis in T. reesei.
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Affiliation(s)
- Jinling Lan
- College of Plant Protection, Jilin Agricultural University
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences
- National Center of Technology Innovation for Synthetic Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences
| | - Lin Zhang
- College of Plant Protection, Jilin Agricultural University
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences
- National Center of Technology Innovation for Synthetic Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences
| | - Jie Gao
- College of Plant Protection, Jilin Agricultural University
| | - Ronglin He
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences
- National Center of Technology Innovation for Synthetic Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences
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Gao L, Yu Z, Wang S, Hou Y, Zhang S, Zhou C, Wu X. A new paradigm in lignocellulolytic enzyme cocktail optimization: Free from expert-level prior knowledge and experimental datasets. BIORESOURCE TECHNOLOGY 2023; 388:129758. [PMID: 37717701 DOI: 10.1016/j.biortech.2023.129758] [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: 08/04/2023] [Revised: 09/05/2023] [Accepted: 09/07/2023] [Indexed: 09/19/2023]
Abstract
Effectively pairing diverse lignocellulolytic enzyme cocktails with intricately structured lignocellulosic substrates is an enduring challenge for science and technology. To date, extensive trial-and-error remains the primary approach and no deep-learning methods were developed to address it due to limited experimental data and incomplete expert-level knowledge of enzyme-cocktail-substrate structure-dynamics-function relationships. Here, a novel model is developed to tackle this issue in efficient, cost-effective, and high-throughput manners. It needs no pre-labeled datasets, instead utilizing simple features, eliminating the reliance on expert-level prior knowledge of reaction mechanisms. Experimentally optimal combinations were found within predicted ranges of tailor-made combinations with precision of 91.98%, covering 80.00% of overall top-100. Practical tests demonstrated its effectiveness in narrowing down potential optimal combinations, speeding up targeted screening, and enabling efficient degradation of lignocellulosic biomass. The method has good applications in artificial proteins biosynthesis from low-value lignocellulosic straw, providing alternative solutions for biomass biorefining challenges in complex enzyme-cocktail-substrate interactions.
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Affiliation(s)
- Le Gao
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Zhuohang Yu
- School of Engineering, Dali University, Dali, Yunnan 671003, China
| | - Shengjie Wang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China
| | - Yuejie Hou
- School of Engineering, Dali University, Dali, Yunnan 671003, China
| | - Shouchang Zhang
- School of Engineering, Dali University, Dali, Yunnan 671003, China
| | - Chichun Zhou
- School of Engineering, Dali University, Dali, Yunnan 671003, China.
| | - Xin Wu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, Tianjin 300308, China.
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Ricci A, Díaz AB, Lazzi C, Blandino Garrido AM. Valorization of orange peels exploiting fungal solid-state and lacto-fermentation. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2023; 103:4614-4624. [PMID: 36860131 DOI: 10.1002/jsfa.12537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 02/21/2023] [Accepted: 03/01/2023] [Indexed: 06/06/2023]
Abstract
BACKGROUND Orange peels can serve as a cost-effective raw material for the production of lactic acid. Indeed, given their high concentration of carbohydrates and low content of lignin, they represent an important source of fermentable sugars, recoverable after a hydrolytic step. RESULTS In the present article, the fermented solid, obtained after 5 days of Aspergillus awamori growth, was used as the only source of enzymes, mainly composed of xylanase (40.6 IU g-1 of dried washed orange peels) and exo-polygalacturonase (16.3 IU g-1 of dried washed orange peels) activities. After the hydrolysis, the highest concentration of reducing sugars (24.4 g L-1 ) was achieved with 20% fermented and 80% non-fermented orange peels. The hydrolysate was fermented with three lactic acid bacteria strains (Lacticaseibacillus casei 2246 and 2240 and Lacticaseibacillus rhamnosus 1019) which demonstrated good growth ability. The yeast extract supplementation increased the lactic acid production rate and yield. Overall, L. casei 2246 produced the highest concentration of lactic acid in mono-culture. CONCLUSION To the best of our knowledge this is the first study exploiting orange peels as low-cost raw material for the production of lactic acid avoiding the employment of commercial enzymes. The enzymes necessary for the hydrolyses were directly produced during A. awamori fermentation and the reducing sugars obtained were fermented for lactic acid production. Despite this preliminary work carried out to study the feasibility of this approach, the concentrations of reducing sugars and lactic acid produced were encouraging, leaving open the possibility of other studies for the optimization of the strategy proposed here. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Annalisa Ricci
- Department of Food and Drug, University of Parma, Parma, Italy
| | - Ana Belen Díaz
- Department of Chemical Engineering and Food Technology, Faculty of Sciences, International Agro-Food Campus of Excellence (CeiA3), University of Cadiz, Puerto Real, Spain
| | - Camilla Lazzi
- Department of Food and Drug, University of Parma, Parma, Italy
- Interdepartmental Center, SITEIA.PARMA-Centro Interdipartimentale sulla Sicurezza, Tecnologie e Innovazione Agroalimentare, University of Parma, Parma, Italy
| | - Ana María Blandino Garrido
- Department of Chemical Engineering and Food Technology, Faculty of Sciences, International Agro-Food Campus of Excellence (CeiA3), University of Cadiz, Puerto Real, Spain
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Yadav A, Sharma V, Tsai ML, Chen CW, Sun PP, Nargotra P, Wang JX, Dong CD. Development of lignocellulosic biorefineries for the sustainable production of biofuels: Towards circular bioeconomy. BIORESOURCE TECHNOLOGY 2023; 381:129145. [PMID: 37169207 DOI: 10.1016/j.biortech.2023.129145] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/28/2023] [Accepted: 05/04/2023] [Indexed: 05/13/2023]
Abstract
The idea of environment friendly and affordable renewable energy resources has prompted the industry to focus on the set up of biorefineries for sustainable bioeconomy. Lignocellulosic biomass (LCB) is considered as an abundantly available renewable feedstock for the production of biofuels which can potentially reduce the dependence on petrochemical refineries. By utilizing various conversion technologies, an integrated biorefinery platform of LCB can be created, embracing the idea of the 'circular bioeconomy'. The development of effective pretreatment methods and biocatalytic systems by various bioengineering and machine learning approaches could reduce the bioprocessing costs, thereby making biomass-based biorefinery more sustainable. This review summarizes the development and advances in the lignocellulosic biorefineries from the LCB to the final product stage using various different state-of-the-art approaches for the progress of circular bioeconomy. The life cycle assessment which generates knowledge on the environmental impacts related to biofuel production chains is also summarized.
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Affiliation(s)
- Aditya Yadav
- Department of Seafood Science, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Vishal Sharma
- Department of Seafood Science, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Mei-Ling Tsai
- Department of Seafood Science, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Chiu-Wen Chen
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Pei-Pei Sun
- Department of Seafood Science, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Parushi Nargotra
- Department of Seafood Science, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Jia-Xiang Wang
- Department of Seafood Science, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Cheng-Di Dong
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan; Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan.
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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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Improvement of Lignocellulolytic Enzyme Production Mediated by Calcium Signaling in Bacillus subtilis Z2 under Graphene Oxide Stress. Appl Environ Microbiol 2022; 88:e0096022. [PMID: 36121214 PMCID: PMC9552604 DOI: 10.1128/aem.00960-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An increase in exoenzyme production can be enhanced by environmental stresses such as graphene oxide (GO) stress, but the link between the two events is still unclear. In this work, the effect of GO as an environmental stress factor on exoenzyme (lignocellulolytic enzyme, amylase, peptidase, and protease) biosynthesis was investigated in Bacillus subtilis Z2, and a plausible mechanism by which cytosolic Ca2+ regulates lignocellulolytic enzyme production in B. subtilis Z2 subjected to GO stress was proposed. The filter paper-hydrolyzing (FPase [representing total cellulase]), carboxymethylcellulase (CMCase [representing endoglucanase]), and β-glucosidase activities and extracellular protein concentration of the wild-type strain under 10 μg/mL GO stress were 1.37-, 1.64-, 1.24-, and 1.16-fold those of the control (without GO stress), respectively. Correspondingly, the transcription levels of lignocellulolytic enzyme genes, cytosolic Ca2+ level, and biomass concentration of B. subtilis were all increased. With lignocellulolytic enzyme from B. subtilis used to hydrolyze alkali-pretreated rice straw, the released reducing sugar concentration reached 265.53 mg/g, and the removal rates of cellulose, hemicellulose, and lignin were 52.4%, 30.1%, and 7.5%, respectively. Furthermore, transcriptome data revealed that intracellular Ca2+ homeostasis played a key role in regulating the levels of gene transcription related to the synthesis of lignocellulolytic enzymes and exoenzymes. Finally, the use of Ca2+ inhibitors (LaCl3 and EDTA) and deletion of spcF (a calmodulin-like protein gene) further demonstrated that the overexpression of those genes was regulated via calcium signaling in B. subtilis subjected to GO stress. IMPORTANCE To effectively convert lignocellulose into fermentable sugars, high lignocellulolytic enzyme loading is needed. Graphene oxide (GO) has been shown to promote exoenzyme (lignocellulolytic enzyme, amylase, peptidase, and protease) production in some microorganisms; however, the regulatory mechanism of the biosynthesis of lignocellulolytic enzymes under GO stress remains unclear. In this work, the lignocellulolytic enzyme production of B. subtilis under GO stress was investigated, and the potential mechanism by which B. subtilis enhanced lignocellulolytic enzyme production through the calcium signaling pathway under GO stress was proposed. This work revealed the role of calcium signaling in the production of enzymes under external environmental stress and provided a direction to facilitate lignocellulolytic enzyme production by B. subtilis.
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Abstract
Biofuel consists of non-fossil fuel derived from the organic biomass of renewable resources, including plants, animals, microorganisms, and waste. Energy derived from biofuel is known as bioenergy. The reserve of fossil fuels is now limited and continuing to decrease, while at the same time demand for energy is increasing. In order to overcome this scarcity, it is vital for human beings to transfer their dependency on fossil fuels to alternative types of fuel, including biofuels, which are effective methods of fulfilling present and future demands. The current review therefore focusses on second-generation lignocellulosic biofuels obtained from non-edible plant biomass (i.e., cellulose, lignin, hemi-celluloses, non-food material) in a more sustainable manner. The conversion of lignocellulosic feedstock is an important step during biofuel production. It is, however, important to note that, as a result of various technical restrictions, biofuel production is not presently cost efficient, thus leading to the need for improvement in the methods employed. There remain a number of challenges for the process of biofuel production, including cost effectiveness and the limitations of various technologies employed. This leads to a vital need for ongoing and enhanced research and development, to ensure market level availability of lignocellulosic biofuel.
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In Situ Corn Fiber Conversion for Ethanol Improvement by the Addition of a Novel Lignocellulolytic Enzyme Cocktail. J Fungi (Basel) 2022; 8:jof8030221. [PMID: 35330223 PMCID: PMC8951183 DOI: 10.3390/jof8030221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 02/17/2022] [Accepted: 02/17/2022] [Indexed: 11/17/2022] Open
Abstract
Corn mashes have high-viscosity and high-sugar characteristics, which hinders yeast-fermentation efficiency and the ethanol yield increase. The excessive viscosity of corn mash is caused by the unutilized cellulose in corn kernel fiber. A novel lignocellulolytic enzymes cocktail with strong substrate specificity was prepared for high-viscosity, high-sugar corn mash. The in situ conversion of corn mashes with novel lignocellulolytic enzymes at the optimum cellulase dosage of 50 FPU/L resulted in about 12% increased ethanol concentration compared with the reference mash at different batch-fermentation scales. Adding the lignocellulolytic enzymes caused the greatest decrease in viscosity of corn mash and residual sugars by 40.9% and 56.3%, respectively. Simultaneously, the application of lignocellulolytic enzymes increased the value of the dried distiller’s grain with solubles (DDGS) by increasing the protein content by 5.51%. The in situ conversion of cellulose can decrease the fermentation broth viscosity and improve the rheological property, thereby improving the ethanol yield. With the same amount of material, the application of the novel enzymes cocktail can enhance the ethanol yield by more than 12%. A quarter of the ethanol yield increase was due to the further hydrolysis of starch, while three quarters to cellulose. Thus, this technology will increase the net revenue of bioethanol industrialization.
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Lian LD, Shi LY, Zhu J, Liu R, Shi L, Ren A, Yu HS, Zhao MW. GlSwi6 Positively Regulates Cellulase and Xylanase Activities through Intracellular Ca2+ Signaling in Ganoderma lucidum. J Fungi (Basel) 2022; 8:jof8020187. [PMID: 35205940 PMCID: PMC8877461 DOI: 10.3390/jof8020187] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 11/23/2022] Open
Abstract
Ganoderma lucidum is a white-rot fungus that produces a range of lignocellulolytic enzymes to decompose lignin and cellulose. The mitogen-activated protein kinase (MAPK) pathway has been implicated in xylanases and cellulases production. As the downstream transcription factor of Slt2-MAPK, the function of Swi6 in G. lucidum has not been fully studied. In this study, the transcription factor GlSwi6 in G. lucidum was characterized and shown to significantly positively regulate cellulases and xylanases production. Knockdown of the GlSwi6 gene decreased the activities of cellulases and xylanases by approximately 31%~38% and 54%~60% compared with those of the wild-type (WT) strain, respectively. Besides, GlSwi6 can be alternatively spliced into two isoforms, GlSwi6A and GlSwi6B, and overexpression of GlSwi6B increased the activities of cellulase and xylanase by approximately 50% and 60%, respectively. Further study indicates that the existence of GlSwi6B significantly increased the concentration of cytosolic Ca2+. Our study indicated that GlSwi6 promotes the activities of cellulase and xylanase by regulating the Ca2+ signaling. These results connected the GlSwi6 and Ca2+ signaling in the regulation of cellulose degradation, and provide an insight for further improvement of cellulase or xylanase activities in G. lucidum as well as other fungi.
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Zhao K, Liu Z, Li M, Hu Y, Yang L, Song X, Qin Y. Drafting Penicillium oxalicum calcineurin-CrzA pathway by combining the analysis of phenotype, transcriptome, and endogenous protein-protein interactions. Fungal Genet Biol 2021; 158:103652. [PMID: 34920105 DOI: 10.1016/j.fgb.2021.103652] [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: 08/13/2021] [Revised: 11/17/2021] [Accepted: 12/08/2021] [Indexed: 11/04/2022]
Abstract
Fungi sense environmental signals and coordinate growth, development, and metabolism accordingly. Calcium-calmodulin-calcineurin signaling is a conserved cascade pathway in fungi. One of the most important downstream targets of this pathway is the transcription factor Crz1/CrzA, which plays an essential role in various cellular processes. The putative collaborators of Penicillium oxalicum CrzA (PoCrzA) were found, through tandem affinity purification followed by mass spectrometric analysis (TAP-MS). A total of 50 protein-protein interaction collaborators of PoCrzA were observed. Among them, some collaborators, such as the catalytic subunit of calcineurin (Cna1, calcineurin A), the regulatory catalytic subunit of calcineurin (Cnb1, calcineurin B), and a 14-3-3 protein Bmh1, which were previously reported in yeast, were identified. Some putative collaborators, including two karyopherins (exportin Los1 and importin Srp1), two kinases (Fus3 and Slt2p), and a general transcriptional corepressor (Cyc8), were also found. The CrzA deletion mutant ΔPocrzA exhibited slow hyphal growth, impaired conidiogenesis, and reduced extracellular cellulase synthesis. Phenotype and transcriptome analysis showed that PoCrzA regulated fungal development in a Flbs-BrlA-dependent manner and participated in cellulase synthesis by modulating cellulolytic gene expression. On the basis of the results of TAP-MS, transcriptome, and phenotypic analysis in P. oxalicum, our study was the first to draft the calcineurin-CrzA pathway in cellulolytic fungi.
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Affiliation(s)
- Kaili Zhao
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Zhongjiao Liu
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Mengxue Li
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Yueyan Hu
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Ling Yang
- Vocational Education College, Dezhou University, Dezhou 253023, China.
| | - Xin Song
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
| | - Yuqi Qin
- National Glycoengineering Research Center, Shandong University, No. 72 Binhai Road, Qingdao 266237, China; State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No. 72 Binhai Road, Qingdao 266237, China.
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Waghmare PR, Waghmare PP, Gao L, Sun W, Qin Y, Liu G, Qu Y. Efficient Constitutive Expression of Cellulolytic Enzymes in Penicillium oxalicum for Improved Efficiency of Lignocellulose Degradation. J Microbiol Biotechnol 2021; 31:740-746. [PMID: 33746194 PMCID: PMC9705867 DOI: 10.4014/jmb.2101.01003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 03/05/2021] [Accepted: 03/10/2021] [Indexed: 12/15/2022]
Abstract
Efficient cellulolytic enzyme production is important for the development of lignocellulose-degrading enzyme mixtures. However, purification of cellulases from their native hosts is time- and labor-consuming. In this study, a constitutive expression system was developed in Penicillium oxalicum for the secreted production of proteins. Using a constitutive polyubiquitin gene promoter and cultivating with glucose as the sole carbon source, nine cellulolytic enzymes of different origins with relatively high purity were produced within 48 h. When supplemented to a commercial cellulase preparation, cellobiohydrolase I from P. funiculosum and cellobiohydrolase II from Talaromyces verruculosus showed remarkable enhancing effects on the hydrolysis of steam-exploded corn stover. Additionally, a synergistic effect was observed for these two cellobiohydrolases during the hydrolysis. Taken together, the constitutive expression system provides a convenient tool for the production of cellulolytic enzymes, which is expected to be useful in the development of highly efficient lignocellulose-degrading enzyme mixtures.
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Affiliation(s)
| | | | - Liwei Gao
- State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China,Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Shandong 266101, P. R. China
| | - Wan Sun
- State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China,National Glycoengineering Research Center, Shandong University, Shandong 266237, P. R. China
| | - Yuqi Qin
- State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China,National Glycoengineering Research Center, Shandong University, Shandong 266237, P. R. China
| | - Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China,National Glycoengineering Research Center, Shandong University, Shandong 266237, P. R. China,Corresponding author Phone: +86-532-58632406 Fax: +86-532-58631501 E-mail:
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Shandong 266237, P. R. China,National Glycoengineering Research Center, Shandong University, Shandong 266237, P. R. China
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Curci N, Strazzulli A, Iacono R, De Lise F, Maurelli L, Di Fenza M, Cobucci-Ponzano B, Moracci M. Xyloglucan Oligosaccharides Hydrolysis by Exo-Acting Glycoside Hydrolases from Hyperthermophilic Microorganism Saccharolobus solfataricus. Int J Mol Sci 2021; 22:3325. [PMID: 33805072 PMCID: PMC8037949 DOI: 10.3390/ijms22073325] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/19/2021] [Accepted: 03/22/2021] [Indexed: 12/16/2022] Open
Abstract
In the field of biocatalysis and the development of a bio-based economy, hemicellulases have attracted great interest for various applications in industrial processes. However, the study of the catalytic activity of the lignocellulose-degrading enzymes needs to be improved to achieve the efficient hydrolysis of plant biomasses. In this framework, hemicellulases from hyperthermophilic archaea show interesting features as biocatalysts and provide many advantages in industrial applications thanks to their stability in the harsh conditions encountered during the pretreatment process. However, the hemicellulases from archaea are less studied compared to their bacterial counterpart, and the activity of most of them has been barely tested on natural substrates. Here, we investigated the hydrolysis of xyloglucan oligosaccharides from two different plants by using, both synergistically and individually, three glycoside hydrolases from Saccharolobus solfataricus: a GH1 β-gluco-/β-galactosidase, a α-fucosidase belonging to GH29, and a α-xylosidase from GH31. The results showed that the three enzymes were able to release monosaccharides from xyloglucan oligosaccharides after incubation at 65 °C. The concerted actions of β-gluco-/β-galactosidase and the α-xylosidase on both xyloglucan oligosaccharides have been observed, while the α-fucosidase was capable of releasing all α-linked fucose units from xyloglucan from apple pomace, representing the first GH29 enzyme belonging to subfamily A that is active on xyloglucan.
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Affiliation(s)
- Nicola Curci
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, 80126 Naples, Italy; (N.C.); (A.S.); (R.I.); (M.M.)
- Institute of Biosciences and BioResources—National Research Council of Italy, 80131 Naples, Italy; (F.D.L.); (L.M.); (M.D.F.)
| | - Andrea Strazzulli
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, 80126 Naples, Italy; (N.C.); (A.S.); (R.I.); (M.M.)
- Task Force on Microbiome Studies, University of Naples Federico II, 80134 Naples, Italy
| | - Roberta Iacono
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, 80126 Naples, Italy; (N.C.); (A.S.); (R.I.); (M.M.)
| | - Federica De Lise
- Institute of Biosciences and BioResources—National Research Council of Italy, 80131 Naples, Italy; (F.D.L.); (L.M.); (M.D.F.)
| | - Luisa Maurelli
- Institute of Biosciences and BioResources—National Research Council of Italy, 80131 Naples, Italy; (F.D.L.); (L.M.); (M.D.F.)
| | - Mauro Di Fenza
- Institute of Biosciences and BioResources—National Research Council of Italy, 80131 Naples, Italy; (F.D.L.); (L.M.); (M.D.F.)
| | - Beatrice Cobucci-Ponzano
- Institute of Biosciences and BioResources—National Research Council of Italy, 80131 Naples, Italy; (F.D.L.); (L.M.); (M.D.F.)
| | - Marco Moracci
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte S. Angelo, 80126 Naples, Italy; (N.C.); (A.S.); (R.I.); (M.M.)
- Task Force on Microbiome Studies, University of Naples Federico II, 80134 Naples, Italy
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Méndez-Líter JA, de Eugenio LI, Nieto-Domínguez M, Prieto A, Martínez MJ. Hemicellulases from Penicillium and Talaromyces for lignocellulosic biomass valorization: A review. BIORESOURCE TECHNOLOGY 2021; 324:124623. [PMID: 33434871 DOI: 10.1016/j.biortech.2020.124623] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/21/2020] [Accepted: 12/23/2020] [Indexed: 05/26/2023]
Abstract
The term hemicellulose groups different polysaccharides with heterogeneous structures, mannans, xyloglucans, mixed-linkage β-glucans and xylans, which differ in their backbone and branches, and in the type and distribution of glycosidic linkages. The enzymatic degradation of these complex polymers requires the concerted action of multiple hemicellulases and auxiliary enzymes. Most commercial enzymes are produced by Trichoderma and Aspergillus species, but recent studies have disclosed Penicillium and Talaromyces as promising sources of hemicellulases. In this review, we summarize the current knowledge on the hemicellulolytic system of these genera, and the role of hemicellulases in the disruption and synthesis of glycosidic bonds. In both cases, the enzymes from Penicillium and Talaromyces represent an interesting alternative for valorization of lignocellulosic biomass in the current framework of circular economy.
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Affiliation(s)
- Juan A Méndez-Líter
- Biotechnology for Lignocellulosic Biomass Group, Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), c/ Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Laura I de Eugenio
- Biotechnology for Lignocellulosic Biomass Group, Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), c/ Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Manuel Nieto-Domínguez
- Biotechnology for Lignocellulosic Biomass Group, Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), c/ Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Alicia Prieto
- Biotechnology for Lignocellulosic Biomass Group, Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), c/ Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - María Jesús Martínez
- Biotechnology for Lignocellulosic Biomass Group, Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), c/ Ramiro de Maeztu 9, 28040 Madrid, Spain.
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16
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Bacterial valorization of pulp and paper industry process streams and waste. Appl Microbiol Biotechnol 2021; 105:1345-1363. [PMID: 33481067 DOI: 10.1007/s00253-021-11107-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 12/28/2020] [Accepted: 01/08/2021] [Indexed: 10/22/2022]
Abstract
The pulp and paper industry is a major source of lignocellulose-containing streams. The components of lignocellulose material are lignin, hemicellulose, and cellulose that may be hydrolyzed into their smaller components and used as feedstocks for valorization efforts. Much of this material is contained in underutilized streams and waste products, such as black liquor, pulp and paper sludge, and wastewater. Bacterial fermentation strategies have suitable potential to upgrade lignocellulosic biomass contained in these streams to value-added chemicals. Bacterial conversion allows for a sustainable and economically feasible approach to valorizing these streams, which can bolster and expand applications of the pulp and paper industry. This review discusses the composition of pulp and paper streams, bacterial isolates from process streams that can be used for lignocellulose biotransformations, and technological approaches for improving valorization efforts. KEY POINTS: • Reviews the conversion of pulp and paper industry waste by bacterial isolates. • Metabolic pathways for the breakdown of lignocellulose components. • Methods for isolating bacteria, determining value-added products, and increasing product yields.
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Abstract
Unharvested hardwoods are abundant in eastern Canada, due to the low quality of their fiber and the absence of outlets in conventional wood transformation industries. The objective of this study was to assess the biochemical and thermochemical energy conversion potential of decaying hardwoods and compare their relationships with external and internal indicators of tree degradation. We characterized how wood-decay processes altered the physical and chemical properties of these woods and affected their digestibility yield and their performance according to indexes of stability and efficiency of combustion. DNA analysis on wood samples was also performed to determine the relative abundance of white-rot fungi compared to that of other saprotrophs. All properties stayed within the range of variations allowing the wood to remain suitable for conversion into bioenergy, even with increased decay. We found no significant differences in the physical and chemical properties that are crucial for energy production between wood from externally-assessed live and decayed trees. However, the proportion of wood area affected by rot was significantly associated with increased digestibility yield, and with decreased combustion reactivity. We could not detect any specific effect associated with increased relative abundance of white-rot fungi. These results suggest that the utilization of biomass from decayed hardwoods instead of live trees for bioenergy production should not alter the conversion efficiency and even potentially increase the performance of biochemical pathways, and hence, support their use as feedstock for bioenergy production.
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Meng QS, Zhang F, Wang W, Liu CG, Zhao XQ, Bai FW. Engineering the Effector Domain of the Artificial Transcription Factor to Improve Cellulase Production by Trichoderma reesei. Front Bioeng Biotechnol 2020; 8:675. [PMID: 32671045 PMCID: PMC7330100 DOI: 10.3389/fbioe.2020.00675] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 06/01/2020] [Indexed: 11/13/2022] Open
Abstract
Filamentous fungal strains of Trichoderma reesei have been widely used for cellulase production, and great effort has been devoted to enhancing their cellulase titers for the economic biorefinery of lignocellulosic biomass. In our previous studies, artificial zinc finger proteins (AZFPs) with the Gal4 effector domain were used to enhance cellulase biosynthesis in T. reesei, and it is of great interest to modify the AZFPs to further improve cellulase production. In this study, the endogenous activation domain from the transcription activator Xyr1 was used to replace the activation domain of Gal4 of the AZFP to explore impact on cellulase production. The cellulase producer T. reesei TU-6 was used as a host strain, and the engineered strains containing the Xyr1 and the Gal4 activation domains were named as T. reesei QS2 and T. reesei QS1, respectively. Compared to T. reesei QS1, activities of filter paper and endoglucanases in crude cellulase produced by T. reesei QS2 increased 24.6 and 50.4%, respectively. Real-time qPCR analysis also revealed significant up-regulation of major genes encoding cellulase in T. reesei QS2. Furthermore, the biomass hydrolytic performance of the cellulase was evaluated, and 83.8 and 97.9% more glucose was released during the hydrolysis of pretreated corn stover using crude enzyme produced by T. reesei QS2, when compared to the hydrolysis with cellulase produced by T. reesei QS1 and the parent strain T. reesei TU-6. As a result, we proved that the effector domain in the AZFPs can be optimized to construct more effective artificial transcription factors for engineering T. reesei to improve its cellulase production.
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Affiliation(s)
- Qing-Shan Meng
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Fei Zhang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Wei Wang
- State Key Lab of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Chen-Guang Liu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xin-Qing Zhao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Feng-Wu Bai
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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Jacomini D, Bussler L, Corrêa JM, Kadowaki MK, Maller A, da-Conceição Silva JL, Simão RDCG. Cloning, expression and characterization of C. crescentus xynA2 gene and application of Xylanase II in the deconstruction of plant biomass. Mol Biol Rep 2020; 47:4427-4438. [PMID: 32424521 DOI: 10.1007/s11033-020-05507-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Accepted: 05/08/2020] [Indexed: 11/24/2022]
Abstract
Biotechnology offers innovative alternatives for industrial bioprocesses mainly because it uses enzymes that biodegrade the hemicellulose releasing fermentable sugars. Caulobacter crescentus (C. crescentus) has seven genes responsible for xylanolytic cleavage, 5 to β-xylosidases (EC 3.2.1.37) and 2 for endoxylanases, like xynA2 (CCNA_03137) that encodes Xylanase II (EC 3.2.1.8) of the glycohydrolases-GH10 group. The xynA2 gene was amplified by PCR, cloned into the pTrcHisA vector e efficiently overexpressed in E. coli providing a His-tag fusion protein. Recombinant xylanase (XynA2) was purified by affinity chromatography using a nickel sepharose column and exhibited a single 43 kDa band on SDS-PAGE gel. XynA2 showed an optimum alkaline pH (8) and stability at alkaline pH for 24 h. Although C. crescentus is mesophilic, XynA2 has optimum temperature of 60 °C and is thermo-resistance at 65 °C. XynA maintains 66% of the enzymatic activity at high temperatures (90 °C) without being denatured.The enzyme displayed a xylanolitic activity free of cellulase to xylan from beechwood and it was not inhibited in the presence of 50 μmol mL-1 of xylose. In addition, dithiothreitol (DTT) induced XynA2 activity, as it improved its kinetic parameters by lowering the KM (5.78 μmol mL-1) and increasing the KCat/KM ratio (1.63 U s-1). Finally, C. crescentus XynA2 efficiently hydrolyzed corn straw with high release of reducing sugars that can be applied in different branches of the industry.
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Affiliation(s)
- Débora Jacomini
- Laboratório de Bioquímica Molecular, Centro de Ciências Exatas e Tecnológicas, Universidade Estadual do Oeste do Paraná, Cascavel,, Paraná, 85814-110, Brazil
| | - Larissa Bussler
- Laboratório de Bioquímica Molecular, Centro de Ciências Exatas e Tecnológicas, Universidade Estadual do Oeste do Paraná, Cascavel,, Paraná, 85814-110, Brazil
| | - Juliana Moço Corrêa
- Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Rua Universitária, 2069, Cascavel, PR, 85814-110, Brazil
| | - Marina Kimiko Kadowaki
- Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Rua Universitária, 2069, Cascavel, PR, 85814-110, Brazil
| | - Alexandre Maller
- Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Rua Universitária, 2069, Cascavel, PR, 85814-110, Brazil
| | - José Luis da-Conceição Silva
- Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Rua Universitária, 2069, Cascavel, PR, 85814-110, Brazil
| | - Rita de Cássia Garcia Simão
- Laboratório de Bioquímica Molecular, Centro de Ciências Exatas e Tecnológicas, Universidade Estadual do Oeste do Paraná, Cascavel,, Paraná, 85814-110, Brazil. .,Laboratório de Bioquímica Molecular, Centro de Ciências Médicas e Farmacêuticas, Universidade Estadual do Oeste do Paraná, Rua Universitária, 2069, Cascavel, PR, 85814-110, Brazil.
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Yang T, Guo Y, Gao N, Li X, Zhao J. Modification of a cellulase system by engineering Penicillium oxalicum to produce cellulose nanocrystal. Carbohydr Polym 2020; 234:115862. [DOI: 10.1016/j.carbpol.2020.115862] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 01/10/2020] [Accepted: 01/11/2020] [Indexed: 12/31/2022]
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21
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Gao L, Xu Y, Song X, Li S, Xia C, Xu J, Qin Y, Liu G, Qu Y. Deletion of the middle region of the transcription factor ClrB in Penicillium oxalicum enables cellulase production in the presence of glucose. J Biol Chem 2019; 294:18685-18697. [PMID: 31659120 DOI: 10.1074/jbc.ra119.010863] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/21/2019] [Indexed: 11/06/2022] Open
Abstract
Enzymes that degrade lignocellulose to simple sugars are of great interest in research and for biotechnology because of their role in converting plant biomass to fuels and chemicals. The synthesis of cellulolytic enzymes in filamentous fungi is tightly regulated at the transcriptional level, with the transcriptional activator ClrB/CLR-2 playing a critical role in many species. In Penicillium oxalicum, clrB overexpression could not relieve the dependence of cellulase expression on cellulose as an inducer, suggesting that clrB is controlled post-transcriptionally. In this study, using a reporter gene system in yeast, we identified the C-terminal region of ClrB/CLR-2 as a transcriptional activation domain. Expression of clrBID , encoding a ClrB derivative in which the DNA-binding and transcriptional activation domains are fused together to remove the middle region, led to cellulase production in the absence of cellulose in P. oxalicum Strikingly, the clrBID -expressing strain produced cellulase on carbon sources that normally repress cellulase expression, including glucose and glycerol. Results from deletion of the carbon catabolite repressor gene creA in the clrBID -expressing strain suggested that the effect of clrBID is independent of CreA's repressive function. A similar modification of clrB in Aspergillus niger resulted in the production of a mannanase in glucose medium. Taken together, these results indicate that ClrB suppression under noninducing conditions involves its middle region, suggesting a potential strategy to engineer fungal strains for improved cellulase production on commonly used carbon sources.
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Affiliation(s)
- Liwei Gao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Yanning Xu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Xin Song
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Shiying Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Chengqiang Xia
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Jiadi Xu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, Qingdao 266237, China
| | - Yuqi Qin
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, Qingdao 266237, China
| | - Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, Qingdao 266237, China.
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, Qingdao 266237, China
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Champreda V, Mhuantong W, Lekakarn H, Bunterngsook B, Kanokratana P, Zhao XQ, Zhang F, Inoue H, Fujii T, Eurwilaichitr L. Designing cellulolytic enzyme systems for biorefinery: From nature to application. J Biosci Bioeng 2019; 128:637-654. [PMID: 31204199 DOI: 10.1016/j.jbiosc.2019.05.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 05/06/2019] [Accepted: 05/11/2019] [Indexed: 12/14/2022]
Abstract
Cellulolytic enzymes play a key role on conversion of lignocellulosic plant biomass to biofuels and biochemicals in sugar platform biorefineries. In this review, we survey composite carbohydrate-active enzymes (CAZymes) among groups of cellulolytic fungi and bacteria that exist under aerobic and anaerobic conditions. Recent advances in designing effective cellulase mixtures are described, starting from the most complex microbial consortium-based enzyme preparations, to single-origin enzymes derived from intensively studied cellulase producers such as Trichoderma reesei, Talaromyces cellulolyticus, and Penicellium funiculosum, and the simplest minimal enzyme systems comprising selected sets of mono-component enzymes tailor-made for specific lignocellulosic substrates. We provide a comprehensive update on studies in developing high-performance cellulases for biorefineries.
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Affiliation(s)
- Verawat Champreda
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand.
| | - Wuttichai Mhuantong
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Hataikarn Lekakarn
- Department of Biotechnology, Faculty of Science and Technology, Thammasat University, Rangsit Campus, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Benjarat Bunterngsook
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Pattanop Kanokratana
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Xin-Qing Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Fei Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hiroyuki Inoue
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology, 3-11-32 Kagamiyama, Hiroshima 739-0046, Japan
| | - Tatsuya Fujii
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology, 3-11-32 Kagamiyama, Hiroshima 739-0046, Japan
| | - Lily Eurwilaichitr
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
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Asemoloye MD, Jonathan SG, Ahmad R. Degradation of 2, 2-Dichlorovinyl dimethyl phosphate (dichlorvos) through the rhizosphere interaction between Panicum maximum Jacq and some selected fungi. CHEMOSPHERE 2019; 221:403-411. [PMID: 30648645 DOI: 10.1016/j.chemosphere.2019.01.058] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 01/07/2019] [Accepted: 01/08/2019] [Indexed: 06/09/2023]
Abstract
Many fungi have been reported to enhance the plant responses and degradation of several persistent pollutants in soils. In this study, five dominant fungi strains were identified from a pesticides polluted soil in Nigeria and screened for the expression of phosphoesterase (opd and mpd) and catechol 1, 2-dioxygenase (afk2 and afk4) genes using Reverse Transcriptase-PCR technique. Their rhizosphere interaction with plant (Panicum maximum) was further studied for the degradation of 2, 2 Dichlorovinyl dimethyl phosphate (dichlorvos). Fungal strains were mixed with Spent Mushroom Compost (SMC) of Pleurotus ostreatus in 1:100 w/w and then applied to a sterilized pesticide polluted soil (5 kg) at increasing concentrations of 10, 20, 30 and 40% with two controls (plant only and fungi-SMC mixture only). Degradation efficiency (DE), degradation rate (K1) and half-life (t1/2) of dichlorvos was calculated in each treatment after 90-day of planting. All the strains were registered at NCBI gene-bank with accession numbers KY693969, KY488464, KY488465, KY693971 and KY693972: they all possess the tested genes although mpd and opd were over-expressed in all the strains while afk2 and afk4 were moderately expressed. The plant-fungi-SMC interaction synergistically sped-up dichlorvos degradation rate in less time period, appreciable loss of dichlorvos at 72.23 and 82.70% DE were observed in 30 and 40% treatments respectively as compared to controls 1 and 2 having 62.20 ± 3.07 and 62.33 ± 4.69% DE respectively. In the same way, the 40% treatment gave the best k1 and t1/2 of 1.755 and 0.40 ± 0.02/day respectively.
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Affiliation(s)
- Michael Dare Asemoloye
- Mycology/Fungal Biotechnology Unit, Department of Botany, University of Ibadan, Ibadan, Nigeria.
| | | | - Rafiq Ahmad
- Department of Environmental Sciences, COMSATS Institute of Information Technology, 22060 Abbottabad, Pakistan.
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Li H, Chen X, Xiong L, Luo M, Chen X, Wang C, Huang C, Chen X. Stepwise enzymatic hydrolysis of alkaline oxidation treated sugarcane bagasse for the co-production of functional xylo-oligosaccharides and fermentable sugars. BIORESOURCE TECHNOLOGY 2019; 275:345-351. [PMID: 30597396 DOI: 10.1016/j.biortech.2018.12.063] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 12/18/2018] [Accepted: 12/19/2018] [Indexed: 06/09/2023]
Abstract
High chemical input is required for enzymatic production of xylo-oligosaccharides (XOS) using xylan extracted from lignocellulosic biomass. In this study, enzymatic hydrolysis of alkaline oxidation (AO) treated sugarcane bagasse (SCB) directly for the production of XOS was conducted. The effect of AO pretreatment on the chemical compositions and hydrolytic properties of SCB was investigated. The AO pretreatment conditions with low chemical input for the production of XOS were optimized by orthogonal design. Stepwise enzymatic hydrolysis of AO pretreated SCB with xylanase and cellulase produced XOS (1.78 g/L), meanwhile, the cellulose conversion increased from 84.97% to 91.51% compared with directly enzymatic hydrolysis using cellulase. HPLC-UV and MALDI-TOF-MS analysis indicated that the obtained XOS products were mainly composed of xylobiose and xylose with a small amount of arabinose/4-O-methylglucuronic acid substituted xylotriose and xylotetraose. The proposed strategy for the co-production of functional XOS and fermentable sugars from SCB showed potential of industrial application.
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Affiliation(s)
- Hailong Li
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, People's Republic of China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, People's Republic of China; R&D Center of Xuyi Attapulgite Applied Technology, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Xuyi 211700, People's Republic of China
| | - Xindong Chen
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Lian Xiong
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, People's Republic of China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, People's Republic of China; R&D Center of Xuyi Attapulgite Applied Technology, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Xuyi 211700, People's Republic of China
| | - Mutan Luo
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Xuefang Chen
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, People's Republic of China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, People's Republic of China; R&D Center of Xuyi Attapulgite Applied Technology, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Xuyi 211700, People's Republic of China
| | - Can Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, People's Republic of China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, People's Republic of China; R&D Center of Xuyi Attapulgite Applied Technology, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Xuyi 211700, People's Republic of China
| | - Chao Huang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, People's Republic of China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, People's Republic of China; R&D Center of Xuyi Attapulgite Applied Technology, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Xuyi 211700, People's Republic of China
| | - Xinde Chen
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, People's Republic of China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, People's Republic of China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, People's Republic of China; R&D Center of Xuyi Attapulgite Applied Technology, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Xuyi 211700, People's Republic of China.
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Zhang F, Bunterngsook B, Li JX, Zhao XQ, Champreda V, Liu CG, Bai FW. Regulation and production of lignocellulolytic enzymes from Trichoderma reesei for biofuels production. ADVANCES IN BIOENERGY 2019. [DOI: 10.1016/bs.aibe.2019.03.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Liu G, Qu Y. Engineering of filamentous fungi for efficient conversion of lignocellulose: Tools, recent advances and prospects. Biotechnol Adv 2018; 37:519-529. [PMID: 30576717 DOI: 10.1016/j.biotechadv.2018.12.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 12/13/2018] [Accepted: 12/14/2018] [Indexed: 01/17/2023]
Abstract
Filamentous fungi, as the main producers of lignocellulolytic enzymes in industry, need to be engineered to improve the economy of large-scale lignocellulose conversion. Investigation of the cellular processes involved in lignocellulolytic enzyme production, as well as optimization of enzyme mixtures for higher hydrolysis efficiency, have provided effective targets for the engineering of lignocellulolytic fungi. Recently, the development of efficient genetic manipulation systems in several lignocellulolytic fungi opens up the possibility of systems engineering of these strains. Here, we review the recent progresses made in the engineering of lignocellulolytic fungi and highlight the research gaps in this area.
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Affiliation(s)
- Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China; Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China; National Glycoengineering Research Center, Shandong University, Qingdao 266237, China.
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Fang X, Qu Y. Metabolic Engineering of Fungal Strains for Efficient Production of Cellulolytic Enzymes. FUNGAL CELLULOLYTIC ENZYMES 2018:27-41. [PMCID: PMC7120360 DOI: 10.1007/978-981-13-0749-2_2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Filamentous fungi are widely used for production of cellulase and other cellulolytic enzymes. Metabolic engineering of filamentous fungal strains has been applied to improve enzyme production, and rapid progress has been made in the recent years. In this chapter, genetic tools and methods to develop superior enzyme producers are summarized, which includes establishment of genetic modification systems, selection and redesign of promoters, and metabolic engineering using either native transcription factors or artificial ones. In addition, enhancement of cellulase production through morphology engineering was also discussed. Emerging tools including CRISPR-Cas9-based genome editing and synthetic biology are highlighted, which are speeding up mechanisms elucidation and strain development, and will further facilitate economic cellulolytic enzyme production.
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Affiliation(s)
- Xu Fang
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong China
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Identification of Key Components for the Optimization of Cellulase Mixtures Using a Proteomic Strategy. Methods Mol Biol 2018. [PMID: 29856050 DOI: 10.1007/978-1-4939-7877-9_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Efficient degradation of complex lignocellulosic materials requires the synergistic action of different types of enzymes. Characterizing the compositions of lignocellulolytic enzyme mixtures could provide comprehensive understandings about the enzymatic degradation of lignocelluloses. In this chapter, we present a proteomic strategy for the analysis of enzyme mixtures produced by lignocellulolytic fungi. The described method is easy to carry out and is suitable to determine the composition of lignocellulolytic enzyme mixtures in a semiquantitative manner. Comparison of the compositions of enzyme mixtures with different degrading efficiencies allows for the identification of candidate targets for the optimization of lignocellulolytic enzyme mixtures.
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Qian Y, Zhong L, Gao J, Sun N, Wang Y, Sun G, Qu Y, Zhong Y. Production of highly efficient cellulase mixtures by genetically exploiting the potentials of Trichoderma reesei endogenous cellulases for hydrolysis of corncob residues. Microb Cell Fact 2017; 16:207. [PMID: 29162107 PMCID: PMC5696804 DOI: 10.1186/s12934-017-0825-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Accepted: 11/14/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Trichoderma reesei is one of the most important fungi utilized for cellulase production. However, its cellulase system has been proven to be present in suboptimal ratio for deconstruction of lignocellulosic substrates. Although previous enzymatic optimization studies have acquired different types of in vitro synthetic mixtures for efficient lignocellulose hydrolysis, production of in vivo optimized cellulase mixtures by industrial strains remains one of the obstacles to reduce enzyme cost in the biofuels production from lignocellulosic biomass. RESULTS In this study, we used a systematic genetic strategy based on the pyrG marker to overexpress the major cellulase components in a hypercellulolytic T. reesei strain and produce the highly efficient cellulase mixture for saccharification of corncob residues. We found that overexpression of CBH2 exhibited a 32-fold increase in the transcription level and a comparable protein level to CBH1, the most abundant secreted protein in T. reesei, but did not contribute much to the cellulolytic ability. However, when EG2 was overexpressed with a 46-fold increase in the transcription level and a comparable protein level to CBH2, the engineered strain QPE36 showed a 1.5-fold enhancement in the total cellulase activity (up to 5.8 U/mL FPA) and a significant promotion of saccharification efficiency towards differently pretreated corncob residues. To assist the following genetic manipulations, the marker pyrG was successfully excised by homologous recombination based on resistance to 5-FOA. Furthermore, BGL1 was overexpressed in the EG2 overexpression strain QE51 (pyrG-excised) and a 11.6-fold increase in BGL activity was obtained. The EG2-BGL1 double overexpression strain QEB4 displayed a remarkable enhancement of cellulolytic ability on pretreated corncob residues. Especially, a nearly complete cellulose conversion (94.2%) was found for the delignified corncob residues after 48 h enzymatic saccharification. CONCLUSIONS These results demonstrate that genetically exploiting the potentials of T. reesei endogenous cellulases to produce highly efficient cellulase mixtures is a powerful strategy to promote the saccharification efficiency, which will eventually facilitate cost reduction for lignocellulose-based biofuels.
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Affiliation(s)
- Yuanchao Qian
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China
| | - Lixia Zhong
- Shandong Institute for Food and Drug Control, Jinan, 250101, People's Republic of China
| | - Jia Gao
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China
| | - Ningning Sun
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China
| | - Yifan Wang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China
| | - Guoyong Sun
- Anaesthesiology Department of the Second Hospital of Shandong University, Jinan, 250100, People's Republic of China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, People's Republic of China.
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Hüttner S, Nguyen TT, Granchi Z, Chin-A-Woeng T, Ahrén D, Larsbrink J, Thanh VN, Olsson L. Combined genome and transcriptome sequencing to investigate the plant cell wall degrading enzyme system in the thermophilic fungus Malbranchea cinnamomea. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:265. [PMID: 29158777 PMCID: PMC5683368 DOI: 10.1186/s13068-017-0956-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 11/04/2017] [Indexed: 05/09/2023]
Abstract
BACKGROUND Genome and transcriptome sequencing has greatly facilitated the understanding of biomass-degrading mechanisms in a number of fungal species. The information obtained enables the investigation and discovery of genes encoding proteins involved in plant cell wall degradation, which are crucial for saccharification of lignocellulosic biomass in second-generation biorefinery applications. The thermophilic fungus Malbranchea cinnamomea is an efficient producer of many industrially relevant enzymes and a detailed analysis of its genomic content will considerably enhance our understanding of its lignocellulolytic system and promote the discovery of novel proteins. RESULTS The 25-million-base-pair genome of M. cinnamomea FCH 10.5 was sequenced with 225× coverage. A total of 9437 protein-coding genes were predicted and annotated, among which 301 carbohydrate-active enzyme (CAZyme) domains were found. The putative CAZymes of M. cinnamomea cover cellulases, hemicellulases, chitinases and pectinases, equipping the fungus with the ability to grow on a wide variety of biomass types. Upregulation of 438 and 150 genes during growth on wheat bran and xylan, respectively, in comparison to growth on glucose was revealed. Among the most highly upregulated CAZymes on xylan were glycoside hydrolase family GH10 and GH11 xylanases, as well as a putative glucuronoyl esterase and a putative lytic polysaccharide monooxygenase (LPMO). AA9-domain-containing proteins were also found to be upregulated on wheat bran, as well as a putative cutinase and a protein harbouring a CBM9 domain. Several genes encoding secreted proteins of unknown function were also more abundant on wheat bran and xylan than on glucose. CONCLUSIONS The comprehensive combined genome and transcriptome analysis of M. cinnamomea provides a detailed insight into its response to growth on different types of biomass. In addition, the study facilitates the further exploration and exploitation of the repertoire of industrially relevant lignocellulolytic enzymes of this fungus.
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Affiliation(s)
- Silvia Hüttner
- Department of Biology and Biological Engineering, Division of Industrial Biotechnology, Chalmers University of Technology, 412 96 Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Thanh Thuy Nguyen
- Centre for Industrial Microbiology, Food Industries Research Institute, Thanh Xuan, Ha Noi, Vietnam
| | - Zoraide Granchi
- GenomeScan B.V., Plesmanlaan 1/D, 2333 BZ Leiden, The Netherlands
| | | | - Dag Ahrén
- National Bioinformatics Infrastructure Sweden (NBIS), Institute of Biology, Lund University, 223 62 Lund, Sweden
| | - Johan Larsbrink
- Department of Biology and Biological Engineering, Division of Industrial Biotechnology, Chalmers University of Technology, 412 96 Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Vu Nguyen Thanh
- Centre for Industrial Microbiology, Food Industries Research Institute, Thanh Xuan, Ha Noi, Vietnam
| | - Lisbeth Olsson
- Department of Biology and Biological Engineering, Division of Industrial Biotechnology, Chalmers University of Technology, 412 96 Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, 412 96 Gothenburg, Sweden
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Heterologous expression and biochemical studies of a thermostable glucose tolerant β-glucosidase from Methylococcus capsulatus ( bath strain ). Int J Biol Macromol 2017; 102:805-812. [DOI: 10.1016/j.ijbiomac.2017.04.078] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 04/20/2017] [Accepted: 04/21/2017] [Indexed: 12/18/2022]
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Li Y, Zhang X, Xiong L, Mehmood MA, Zhao X, Bai F. On-site cellulase production and efficient saccharification of corn stover employing cbh2 overexpressing Trichoderma reesei with novel induction system. BIORESOURCE TECHNOLOGY 2017; 238:643-649. [PMID: 28486197 DOI: 10.1016/j.biortech.2017.04.084] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 04/20/2017] [Accepted: 04/21/2017] [Indexed: 05/05/2023]
Abstract
Although on-site cellulase production offers cost-effective saccharification of lignocellulosic biomass, low enzyme titer is still a barrier for achieving robustness. In the present study, a strain of T. reesei was developed for enhanced production of cellulase via overexpression of Cellobiohydrolase II. Furthermore, optimum enzyme production was achieved using a novel inducer mixture containing synthesized glucose-sophorose (MGD) and alkali pre-treated corn stover (APCS). Within 60h, a remarkably higher cellulase productivity and activity were achieved in the fed-batch fermentation using the optimized ratio of MGD and APCS in the inducer mixture, compared to those reported using cellulosic biomass as the sole inducer. After the enzyme production, APCS was added directly into the fermentation broth at 20% solid loading, which produced 122.5g/L glucose and 40.21g/L xylose, leading to the highest yield reported so far. The improved enzyme titers during on-site cellulase production would benefit cost-competitive saccharification of lignocellulosic biomass.
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Affiliation(s)
- Yonghao Li
- State Key Laboratory of Microbial Metabolism & School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116023, China.
| | - Xiaoyue Zhang
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116023, China.
| | - Liang Xiong
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116023, China.
| | - Muhammad Aamer Mehmood
- State Key Laboratory of Microbial Metabolism & School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; Bioenergy Research Centre, Department of Bioinformatics & Biotechnology, Government College University Faisalabad, Faisalabad 38000, Pakistan.
| | - Xinqing Zhao
- State Key Laboratory of Microbial Metabolism & School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Fengwu Bai
- State Key Laboratory of Microbial Metabolism & School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116023, China.
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Ibrahim E, Jones KD, Taylor KE, Hosseney EN, Mills PL, Escudero JM. Molecular and biochemical characterization of recombinant cel12B, cel8C, and peh28 overexpressed in Escherichia coli and their potential in biofuel production. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:52. [PMID: 28413443 PMCID: PMC5327597 DOI: 10.1186/s13068-017-0732-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 02/11/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND The high crystallinity of cellulosic biomass myofibrils as well as the complexity of their intermolecular structure is a significant impediment for biofuel production. Cloning of celB-, celC-encoded cellulases (cel12B and cel8C) and peh-encoded polygalacturonase (peh28) from Pectobacterium carotovorum subsp. carotovorum (Pcc) was carried out in our previous study using Escherichia coli as a host vector. The current study partially characterizes the enzymes' molecular structures as well as their catalytic performance on different substrates which can be used to improve their potential for lignocellulosic biomass conversion. RESULTS β-Jelly roll topology, (α/α)6 antiparallel helices and right-handed β-helices were the folds identified for cel12B, cel8C, and peh28, respectively, in their corresponding protein model structures. Purifications of 17.4-, 6.2-, and 6.0-fold, compared to crude extract, were achieved for cel12B and cel8C, and peh28, respectively, using specific membrane ultrafiltrations and size-exclusion chromatography. Avicel and carboxymethyl cellulose (CMC) were substrates for cel12B, whereas for cel8C catalytic activity was only shown on CMC. The enzymes displayed significant synergy on CMC but not on Avicel when tested for 3 h at 45 °C. No observed β-glucosidase activities were identified for cel8C and cel12B when tested on p-nitrophenyl-β-d-glucopyranoside. Activity stimulation of 130% was observed when a recombinant β-glucosidase from Pcc was added to cel8C and cel12B as tested for 3 h at 45 °C. Optimum temperature and pH of 45 °C and 5.4, respectively, were identified for all three enzymes using various substrates. Catalytic efficiencies (kcat/Km) were calculated for cel12B and cel8C on CMC as 0.141 and 2.45 ml/mg/s respectively, at 45 °C and pH 5.0 and for peh28 on polygalacturonic acid as 4.87 ml/mg/s, at 40 °C and pH 5.0. Glucose and cellobiose were the end-products identified for cel8C, cel12B, and β-glucosidase acting together on Avicel or CMC, while galacturonic acid and other minor co-products were identified for peh28 action on pectin. CONCLUSIONS This study provides some insight into which parameters should be optimized when application of cel8C, cel12B, and peh28 to biomass conversion is the goal.
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Affiliation(s)
- Eman Ibrahim
- Department of Environmental Engineering, Texas A&M University-Kingsville, Kingsville, TX 78363 USA
- Department of Botany and Microbiology, Al-Azhar University, Nasr City, Cairo, 11884 Egypt
| | - Kim D. Jones
- Department of Environmental Engineering, Texas A&M University-Kingsville, Kingsville, TX 78363 USA
| | - Keith E. Taylor
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, ON N9B 3P4 Canada
| | - Ebtesam N. Hosseney
- Department of Botany and Microbiology, Al-Azhar University, Nasr City, Cairo, 11884 Egypt
| | - Patrick L. Mills
- Department of Chemical Engineering, Texas A&M University-Kingsville, Kingsville, TX 78363 USA
| | - Jean M. Escudero
- Department of Basic Science, St. Louis College of Pharmacy, St. Louis, MO 63110-1088 USA
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An aldonolactonase AltA from Penicillium oxalicum mitigates the inhibition of β-glucosidase during lignocellulose biodegradation. Appl Microbiol Biotechnol 2017; 101:3627-3636. [DOI: 10.1007/s00253-017-8134-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/06/2017] [Accepted: 01/10/2017] [Indexed: 10/20/2022]
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Ivanova C, Ramoni J, Aouam T, Frischmann A, Seiboth B, Baker SE, Le Crom S, Lemoine S, Margeot A, Bidard F. Genome sequencing and transcriptome analysis of Trichoderma reesei QM9978 strain reveals a distal chromosome translocation to be responsible for loss of vib1 expression and loss of cellulase induction. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:209. [PMID: 28912831 PMCID: PMC5588705 DOI: 10.1186/s13068-017-0897-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 08/29/2017] [Indexed: 05/05/2023]
Abstract
BACKGROUND The hydrolysis of biomass to simple sugars used for the production of biofuels in biorefineries requires the action of cellulolytic enzyme mixtures. During the last 50 years, the ascomycete Trichoderma reesei, the main source of industrial cellulase and hemicellulase cocktails, has been subjected to several rounds of classical mutagenesis with the aim to obtain higher production levels. During these random genetic events, strains unable to produce cellulases were generated. Here, whole genome sequencing and transcriptomic analyses of the cellulase-negative strain QM9978 were used for the identification of mutations underlying this cellulase-negative phenotype. RESULTS Sequence comparison of the cellulase-negative strain QM9978 to the reference strain QM6a identified a total of 43 mutations, of which 33 were located either close to or in coding regions. From those, we identified 23 single-nucleotide variants, nine InDels, and one translocation. The translocation occurred between chromosomes V and VII, is located upstream of the putative transcription factor vib1, and abolishes its expression in QM9978 as detected during the transcriptomic analyses. Ectopic expression of vib1 under the control of its native promoter as well as overexpression of vib1 under the control of a strong constitutive promoter restored cellulase expression in QM9978, thus confirming that the translocation event is the reason for the cellulase-negative phenotype. Gene deletion of vib1 in the moderate producer strain QM9414 and in the high producer strain Rut-C30 reduced cellulase expression in both cases. Overexpression of vib1 in QM9414 and Rut-C30 had no effect on cellulase production, most likely because vib1 is already expressed at an optimal level under normal conditions. CONCLUSION We were able to establish a link between a chromosomal translocation in QM9978 and the cellulase-negative phenotype of the strain. We identified the transcription factor vib1 as a key regulator of cellulases in T. reesei whose expression is absent in QM9978. We propose that in T. reesei, as in Neurospora crassa, vib1 is involved in cellulase induction, although the exact mechanism remains to be elucidated. The data presented here show an example of a combined genome sequencing and transcriptomic approach to explain a specific trait, in this case the QM9978 cellulase-negative phenotype, and how it helps to better understand the mechanisms during cellulase gene regulation. When focusing on mutations on the single base-pair level, changes on the chromosome level can be easily overlooked and through this work we provide an example that stresses the importance of the big picture of the genomic landscape during analysis of sequencing data.
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Affiliation(s)
- Christa Ivanova
- IFP Energies Nouvelles, 1-4 Avenue de Bois-Préau, 92852 Rueil-Malmaison, France
- Present Address: Genetics of Biofilms Unit, Department of Microbiology, Institut Pasteur, 25-28 Rue du Dr Roux, 75015 Paris, France
| | - Jonas Ramoni
- Molecular Biotechnology, Research Division Biochemical Technology, Institute of Chemical Engineering, TU-Wien, 1060 Vienna, Austria
| | - Thiziri Aouam
- IFP Energies Nouvelles, 1-4 Avenue de Bois-Préau, 92852 Rueil-Malmaison, France
| | - Alexa Frischmann
- Molecular Biotechnology, Research Division Biochemical Technology, Institute of Chemical Engineering, TU-Wien, 1060 Vienna, Austria
| | - Bernhard Seiboth
- Molecular Biotechnology, Research Division Biochemical Technology, Institute of Chemical Engineering, TU-Wien, 1060 Vienna, Austria
| | - Scott E. Baker
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99354 USA
| | - Stéphane Le Crom
- Evolution Paris Seine-Institut de Biologie Paris Seine (EPS-IBPS), Sorbonne Universités, UPMC Univ Paris 06, Univ Antilles, Univ Nice Sophia Antipolis, CNRS, 75005 Paris, France
| | - Sophie Lemoine
- École normale supérieure, PSL Research University, CNRS, Inserm, Institut de Biologie de l’École normale supérieure (IBENS), Plateforme Génomique, 75005 Paris, France
| | - Antoine Margeot
- IFP Energies Nouvelles, 1-4 Avenue de Bois-Préau, 92852 Rueil-Malmaison, France
| | - Frédérique Bidard
- IFP Energies Nouvelles, 1-4 Avenue de Bois-Préau, 92852 Rueil-Malmaison, France
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Gao L, Li Z, Xia C, Qu Y, Liu M, Yang P, Yu L, Song X. Combining manipulation of transcription factors and overexpression of the target genes to enhance lignocellulolytic enzyme production in Penicillium oxalicum. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:100. [PMID: 28428823 PMCID: PMC5397729 DOI: 10.1186/s13068-017-0783-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 04/11/2017] [Indexed: 05/15/2023]
Abstract
BACKGROUND Lignocellulolytic enzymes are the main enzymes to saccharify lignocellulose from renewable plant biomass in the bio-based economy. The production of these enzymes is transcriptionally regulated by multiple transcription factors. We previously engineered Penicillium oxalicum for improved cellulase production via manipulation of three genes in the cellulase expression regulatory network. However, the potential of combinational engineering of multiple regulators and their targets at protein abundance and activity levels has not been fully explored. RESULTS Here, we verified that a point mutation XlnRA871V in transcription factor XlnR enhanced the expression of lignocellulolytic enzymes, particularly hemicellulases, in P. oxalicum. Then, overexpression of XlnRA871V with a constitutive PDE_02864 promoter was combined with the overexpression of cellulase transcriptional activator ClrB and deletion of carbon catabolite repressor CreA. The resulted strain RE-7 showed 8.9- and 51.5-fold increased production of cellulase and xylanase relative to the starting strain M12, respectively. Further overexpression of two major cellulase genes cbh1-2 and eg1 enabled an additional 13.0% improvement of cellulase production. In addition, XlnRA871V led to decreased production of β-glucosidase and amylase, which could be attributed to the reduced transcription of corresponding enzyme-encoding genes. CONCLUSIONS The results illustrated that combinational manipulation of the involved transcription factors and their target genes was a viable strategy for efficient production of lignocellulolytic enzymes in filamentous fungi. The striking negative effect of XlnRA871V mutation on amylase production was also highlighted.
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Affiliation(s)
- Liwei Gao
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, 250100 Shandong China
| | - Zhonghai Li
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, 250100 Shandong China
- Department of Bioengineering, Qilu University of Technology, Jinan, 250353 Shandong China
| | - Chengqiang Xia
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, 250100 Shandong China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, 250100 Shandong China
- National Glycoengineering Research Center, Shandong University, Shan Da Nan Road 27, Jinan, Shandong 250100 China
| | - Meng Liu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, 250100 Shandong China
| | - Piao Yang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, 250100 Shandong China
| | - Lele Yu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, 250100 Shandong China
| | - Xin Song
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, 250100 Shandong China
- National Glycoengineering Research Center, Shandong University, Shan Da Nan Road 27, Jinan, Shandong 250100 China
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He R, Li C, Ma L, Zhang D, Chen S. Effect of highly branched hyphal morphology on the enhanced production of cellulase in Trichoderma reesei DES-15. 3 Biotech 2016; 6:214. [PMID: 28330286 PMCID: PMC5052222 DOI: 10.1007/s13205-016-0516-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 09/08/2016] [Indexed: 01/10/2023] Open
Abstract
The morphology of Trichoderma reesei is a vitally important factor for cellulase productivity. This study investigated the effect of hyphal morphology on cellulase production in the hyper-cellulolytic mutant, T. reesei DES-15. With a distinct morphology, T. reesei DES-15 was obtained through Diethyl sulfite (DES) mutagenesis. The hyphal morphology of DES-15 batch-cultured in a 5-L fermentor was significantly shorter and more branched than the parental strain RUT C30. The cellulase production of DES-15 during batch fermentation was 66 % greater than that of RUT C30 when cultured the same conditions. DES-15 secreted nearly 50 % more protein than RUT C30. The gene expression level of a set of genes (cla4, spa2, ras2, ras1, rhoA, cdc42, and racA) known to be involved in hyphae growth and hyphal branching was measured by quantitative real-time PCR. The transcriptional analysis of these genes demonstrated that a decrease in gene expressions might contribute to the increased hyphal branching seen in DES-15. These results indicated that the highly branching hyphae in DES-15 resulted in increased cellulase production, suggesting that DES-15 may be a good candidate for use in the large-scale production of cellulase.
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Affiliation(s)
- Ronglin He
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
- Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
- Tianjin Key Lab of Industrial Microbiology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Chen Li
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
| | - Lijuan Ma
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, People's Republic of China
| | - Dongyuan Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China.
| | - Shulin Chen
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, People's Republic of China
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Hohmann HP, van Dijl JM, Krishnappa L, Prágai Z. Host Organisms:Bacillus subtilis. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1002/9783527807796.ch7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- Hans-Peter Hohmann
- Nutrition Innovation Center R&D Biotechnology; DSM Nutritional Products Ltd; Wurmisweg 576 CH-4303 Kaiseraugst Switzerland
| | - Jan M. van Dijl
- University of Groningen, University Medical Center Groningen; Department of Medical Microbiology; Hanzeplein 1 9700 RB Groningen The Netherlands
| | - Laxmi Krishnappa
- University of Groningen, University Medical Center Groningen; Department of Medical Microbiology; Hanzeplein 1 9700 RB Groningen The Netherlands
| | - Zoltán Prágai
- Nutrition Innovation Center R&D Biotechnology; DSM Nutritional Products Ltd; Wurmisweg 576 CH-4303 Kaiseraugst Switzerland
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Li Y, Liu C, Bai F, Zhao X. Overproduction of cellulase by Trichoderma reesei RUT C30 through batch-feeding of synthesized low-cost sugar mixture. BIORESOURCE TECHNOLOGY 2016; 216:503-10. [PMID: 27268435 DOI: 10.1016/j.biortech.2016.05.108] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Revised: 05/25/2016] [Accepted: 05/26/2016] [Indexed: 05/05/2023]
Abstract
Cellulase is a prerequisite for the bioconversion of lignocellulosic biomass, but its high cost presents the biggest challenge. In this article, low-cost mixture was produced from glucose through the transglycosylation reaction catalyzed by β-glucosidase for cellulase overproduction by Trichodema reesei RUT C30. As a result, cellulase titer of 90.3FPU/mL, which was more than 10 folds of that achieved with lactose as inducer, was achieved at 144h. Meanwhile, cellulase productivity was drastically increased to 627.1FPU/L/h, at least 3-5 folds higher than previously reported by the fungal species. The crude enzyme was further tested by hydrolyzing NaOH-pretreated corn stover with 15% solid loading, and 96.6g/L glucose was released with 92.6% sugar yield at 96h and 44.8g/L ethanol was obtained.
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Affiliation(s)
- Yonghao Li
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116023, China.
| | - Chenguang Liu
- State Key Laboratory of Microbial Metabolism & School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Fengwu Bai
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116023, China; State Key Laboratory of Microbial Metabolism & School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Xinqing Zhao
- State Key Laboratory of Microbial Metabolism & School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
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40
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Zhao X, Xiong L, Zhang M, Bai F. Towards efficient bioethanol production from agricultural and forestry residues: Exploration of unique natural microorganisms in combination with advanced strain engineering. BIORESOURCE TECHNOLOGY 2016; 215:84-91. [PMID: 27067672 DOI: 10.1016/j.biortech.2016.03.158] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 03/29/2016] [Accepted: 03/30/2016] [Indexed: 05/14/2023]
Abstract
Production of fuel ethanol from lignocellulosic feedstocks such as agricultural and forestry residues is receiving increasing attention due to the unsustainable supply of fossil fuels. Three key challenges include high cellulase production cost, toxicity of the cellulosic hydrolysate to microbial strains, and poor ability of fermenting microorganisms to utilize certain fermentable sugars in the hydrolysate. In this article, studies on searching of natural microbial strains for production of unique cellulase for biorefinery of agricultural and forestry wastes, as well as development of strains for improved cellulase production were reviewed. In addition, progress in the construction of yeast strains with improved stress tolerance and the capability to fully utilize xylose and glucose in the cellulosic hydrolysate was also summarized. With the superior microbial strains for high titer cellulase production and efficient utilization of all fermentable sugars in the hydrolysate, economic biofuels production from agricultural residues and forestry wastes can be realized.
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Affiliation(s)
- Xinqing Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Liang Xiong
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China
| | - Mingming Zhang
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China
| | - Fengwu Bai
- State Key Laboratory of Microbial Metabolism, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China
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41
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Qian Y, Zhong L, Hou Y, Qu Y, Zhong Y. Characterization and Strain Improvement of a Hypercellulytic Variant, Trichoderma reesei SN1, by Genetic Engineering for Optimized Cellulase Production in Biomass Conversion Improvement. Front Microbiol 2016; 7:1349. [PMID: 27621727 PMCID: PMC5002442 DOI: 10.3389/fmicb.2016.01349] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 08/16/2016] [Indexed: 01/20/2023] Open
Abstract
The filamentous fungus Trichoderma reesei is a widely used strain for cellulolytic enzyme production. A hypercellulolytic T. reesei variant SN1 was identified in this study and found to be different from the well-known cellulase producers QM9414 and RUT-C30. The cellulose-degrading enzymes of T. reesei SN1 show higher endoglucanase (EG) activity but lower β-glucosidase (BGL) activity than those of the others. A uracil auxotroph strain, SP4, was constructed by pyr4 deletion in SN1 to improve transformation efficiency. The BGL1-encoding gene bgl1 under the control of a modified cbh1 promoter was overexpressed in SP4. A transformant, SPB2, with four additional copies of bgl1 exhibited a 17.1-fold increase in BGL activity and a 30.0% increase in filter paper activity. Saccharification of corncob residues with crude enzyme showed that the glucose yield of SPB2 is 65.0% higher than that of SP4. These results reveal the feasibility of strain improvement through the development of an efficient genetic transformation platform to construct a balanced cellulase system for biomass conversion.
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Affiliation(s)
- Yuanchao Qian
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University Jinan, China
| | - Lixia Zhong
- Shandong Institute for Food and Drug Control Jinan, China
| | - Yunhua Hou
- Bioengineering Institute, Qilu University of Technology Jinan, China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University Jinan, China
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University Jinan, China
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CAZyChip: dynamic assessment of exploration of glycoside hydrolases in microbial ecosystems. BMC Genomics 2016; 17:671. [PMID: 27552843 PMCID: PMC4994258 DOI: 10.1186/s12864-016-2988-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 08/02/2016] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Microorganisms constitute a reservoir of enzymes involved in environmental carbon cycling and degradation of plant polysaccharides through their production of a vast variety of Glycoside Hydrolases (GH). The CAZyChip was developed to allow a rapid characterization at transcriptomic level of these GHs and to identify enzymes acting on hydrolysis of polysaccharides or glycans. RESULTS This DNA biochip contains the signature of 55,220 bacterial GHs available in the CAZy database. Probes were designed using two softwares, and microarrays were directly synthesized using the in situ ink-jet technology. CAZyChip specificity and reproducibility was validated by hybridization of known GHs RNA extracted from recombinant E. coli strains, which were previously identified by a functional metagenomic approach. The GHs arsenal was also studied in bioprocess conditions using rumen derived microbiota. CONCLUSIONS The CAZyChip appears to be a user friendly tool for profiling the expression of a large variety of GHs. It can be used to study temporal variations of functional diversity, thereby facilitating the identification of new efficient candidates for enzymatic conversions from various ecosystems.
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Woon JSK, Mackeen MM, Mahadi NM, Illias RM, Abdul Murad AM, Abu Bakar FD. Expression and characterization of a cellobiohydrolase (CBH7B) from the thermophilic fungusThielavia terrestrisinPichia pastoris. Biotechnol Appl Biochem 2015; 63:690-698. [DOI: 10.1002/bab.1431] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 08/06/2015] [Indexed: 11/06/2022]
Affiliation(s)
- James Sy-Keen Woon
- School of Biosciences and Biotechnology, Faculty of Science and Technology; Universiti Kebangsaan Malaysia; Selangor Malaysia
| | - Mukram Mohamed Mackeen
- School of Chemical Sciences and Food Technology, Faculty of Science and Technology; Universiti Kebangsaan Malaysia; Selangor Malaysia
- Institute of Systems Biology (INBIOSIS); Universiti Kebangsaan Malaysia; Selangor Malaysia
| | - Nor Muhammad Mahadi
- Institute of Systems Biology (INBIOSIS); Universiti Kebangsaan Malaysia; Selangor Malaysia
- Malaysia Genome Institute; Jalan Bangi Lama; Selangor Malaysia
| | - Rosli Md Illias
- Department of Bioprocess Engineering, Faculty of Chemical Engineering; Universiti Teknologi Malaysia; Johor Malaysia
| | - Abdul Munir Abdul Murad
- School of Biosciences and Biotechnology, Faculty of Science and Technology; Universiti Kebangsaan Malaysia; Selangor Malaysia
| | - Farah Diba Abu Bakar
- School of Biosciences and Biotechnology, Faculty of Science and Technology; Universiti Kebangsaan Malaysia; Selangor Malaysia
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Montella S, Amore A, Faraco V. Metagenomics for the development of new biocatalysts to advance lignocellulose saccharification for bioeconomic development. Crit Rev Biotechnol 2015; 36:998-1009. [PMID: 26381035 DOI: 10.3109/07388551.2015.1083939] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The world economy is moving toward the use of renewable and nonedible lignocellulosic biomasses as substitutes for fossil sources in order to decrease the environmental impact of manufacturing processes and overcome the conflict with food production. Enzymatic hydrolysis of the feedstock is a key technology for bio-based chemical production, and the identification of novel, less expensive and more efficient biocatalysts is one of the main challenges. As the genomic era has shown that only a few microorganisms can be cultured under standard laboratory conditions, the extraction and analysis of genetic material directly from environmental samples, termed metagenomics, is a promising way to overcome this bottleneck. Two screening methodologies can be used on metagenomic material: the function-driven approach of expression libraries and sequence-driven analysis based on gene homology. Both techniques have been shown to be useful for the discovery of novel biocatalysts for lignocellulose conversion, and they enabled identification of several (hemi)cellulases and accessory enzymes involved in (hemi)cellulose hydrolysis. This review summarizes the latest progress in metagenomics aimed at discovering new enzymes for lignocellulose saccharification.
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Affiliation(s)
- Salvatore Montella
- a Department of Chemical Sciences , University of Naples "Federico II", Complesso Universitario Monte S. Angelo , Naples , Italy
| | - Antonella Amore
- a Department of Chemical Sciences , University of Naples "Federico II", Complesso Universitario Monte S. Angelo , Naples , Italy
| | - Vincenza Faraco
- a Department of Chemical Sciences , University of Naples "Federico II", Complesso Universitario Monte S. Angelo , Naples , Italy
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Ferreira PG, da Silveira FA, dos Santos RCV, Genier HLA, Diniz RHS, Ribeiro JI, Fietto LG, Passos FML, da Silveira WB. Optimizing ethanol production by thermotolerant Kluyveromyces marxianus CCT 7735 in a mixture of sugarcane bagasse and ricotta whey. Food Sci Biotechnol 2015. [DOI: 10.1007/s10068-015-0182-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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46
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He R, Guo W, Zhang D. An ethanolamine kinase Eki1 affects radial growth and cell wall integrity inTrichoderma reesei. FEMS Microbiol Lett 2015; 362:fnv133. [DOI: 10.1093/femsle/fnv133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2015] [Indexed: 11/13/2022] Open
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47
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Zhang SB, Wang L, Liu Y, Zhai HC, Cai JP, Hu YS. Expression of feruloyl esterase A from Aspergillus terreus and its application in biomass degradation. Protein Expr Purif 2015; 115:153-7. [PMID: 26282562 DOI: 10.1016/j.pep.2015.08.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 08/13/2015] [Accepted: 08/13/2015] [Indexed: 10/23/2022]
Abstract
Feruloyl esterases (FAEs) are key enzymes involved in the complete biodegradation of lignocelluloses, which could hydrolyze the ester bonds between hemicellulose and lignin. The coding sequence of a feruloyl esterase A (AtFaeA) was cloned from Aspergillus terreus and the recombinant AtFaeA was constitutively expressed in Pichia pastoris. The SDS-PAGE analysis of purified AtFaeA showed two protein bands owing to the different extent of glycosylation, and the recombinant AtFaeA had an optimum temperature of 50°C and an optimum pH of 5.0. The substrate utilization and primary sequence identity of AtFaeA demonstrated that it is a type-A feruloyl esterase. The hydrolysis of corn stalk and corncob by xylanase from Aspergillus niger could be significantly improved in concert with recombinant AfFaeA.
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Affiliation(s)
- Shuai-Bing Zhang
- College of Biological Engineering, Henan University of Technology, Zhengzhou 450001, China.
| | - Le Wang
- College of Biological Engineering, Henan University of Technology, Zhengzhou 450001, China
| | - Yan Liu
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, China
| | - Huan-Chen Zhai
- College of Biological Engineering, Henan University of Technology, Zhengzhou 450001, China
| | - Jing-Ping Cai
- College of Biological Engineering, Henan University of Technology, Zhengzhou 450001, China
| | - Yuan-Sen Hu
- College of Biological Engineering, Henan University of Technology, Zhengzhou 450001, China
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48
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Chang A, Wu Q, Xu W, Xie J, Wu W. Enhanced enzymatic hydrolysis of cellulose in microgels. Chem Commun (Camb) 2015; 51:10502-5. [PMID: 26035077 DOI: 10.1039/c5cc03543k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A cellulose-based microgel, where an individual microgel contains approximately one cellulose chain on average, is synthesized via free radical polymerization of a difunctional small-molecule N,N'-methylenebisacrylamide in cellulose solution. This microgelation leads to a low-ordered cellulose, favoring enzymatic hydrolysis of cellulose to generate glucose.
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Affiliation(s)
- Aiping Chang
- State Key Laboratory for Physical Chemistry of Solid Surfaces, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China.
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Progress and challenges in the engineering of non-cellulolytic microorganisms for consolidated bioprocessing. Curr Opin Biotechnol 2015; 33:32-8. [DOI: 10.1016/j.copbio.2014.10.003] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 10/06/2014] [Accepted: 10/11/2014] [Indexed: 11/23/2022]
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Protein disulfide isomerase homolog TrPDI2 contributing to cellobiohydrolase production in Trichoderma reesei. Enzyme Microb Technol 2015; 77:21-8. [PMID: 26138396 DOI: 10.1016/j.enzmictec.2015.05.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 05/07/2015] [Accepted: 05/19/2015] [Indexed: 11/21/2022]
Abstract
The majority of the cysteine residues in the secreted proteins form disulfide bonds via protein disulfide isomerase (PDI)-mediated catalysis, stabilizing the enzyme activity. The role of PDI in cellulase production is speculative, as well as the possibility of PDI as a target for improving enzyme production efficiency of Trichoderma reesei, a widely used producer of enzyme for the production of lignocellulose-based biofuels and biochemicals. Here, we report that a PDI homolog, TrPDI2 in T. reesei exhibited a 36.94% and an 11.81% similarity to Aspergillus niger TIGA and T. reesei PDI1, respectively. The capability of TrPDI2 to recover the activity of reduced and denatured RNase by promoting refolding verified its protein disulfide isomerase activity. The overexpression of Trpdi2 increased the secretion and the activity of CBH1 at the early stage of cellulase induction. In addition, both the expression level and redox state of TrPDI2 responded to cellulase induction in T. reesei, providing sustainable oxidative power to ensure cellobiohydrolase maturation and production. The results suggest that TrPDI2 may contribute to cellobiohydrolase secretion by enhancing the capability of disulfide bond formation, which is essential for protein folding and maturation.
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