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Cellulosic Ethanol Production Using a Dual Functional Novel Yeast. Int J Microbiol 2022; 2022:7853935. [PMID: 35295685 PMCID: PMC8920679 DOI: 10.1155/2022/7853935] [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: 12/22/2021] [Revised: 02/07/2022] [Accepted: 02/14/2022] [Indexed: 11/18/2022] Open
Abstract
Reducing the cost of cellulosic ethanol production, especially for cellulose hydrolytic enzymes, is vital to growing a sustainable and efficient cellulosic ethanol industry and bio-based economy. Using an ethanologenic yeast able to produce hydrolytic enzymes, such as Clavispora NRRL Y-50464, is one solution. NRRL Y-50464 is fast-growing and robust, and tolerates inhibitory compounds 2-furaldehyde (furfural) and 5-hydroxymethyl-2-furaldehyde (HMF) associated with lignocellulose-to-fuel conversion. It produces three forms of β-glucosidase isozymes, BGL1, BGL2, and BGL3, and ferment cellobiose as the sole carbon source. These β-glucosidases exhibited desirable enzyme kinetic parameters and high levels of enzyme-specific activity toward cellobiose and many oligosaccharide substrates. They tolerate the product inhibition of glucose and ethanol, and are stable to temperature and pH conditions. These characteristics are desirable for more efficient cellulosic ethanol production by simultaneous saccharification and fermentation. NRRL Y-50464 provided the highest cellulosic ethanol titers and conversion rates at lower cellulase loadings, using either pure cellulose or agricultural residues, as so far reported in the literature. This review summarizes NRRL Y-50464 performance on cellulosic ethanol production from refined cellulose, rice straw, and corn stover processed in various ways, in the presence or absence of furfural and HMF. This dual functional yeast has potential to serve as a prototype for the development of next-generation biocatalysts. Perspectives on continued strain development and process engineering improvements for more efficient cellulosic ethanol production from lignocellulosic materials are also discussed.
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Abstract
Cell immobilization is a process augmentation technique aimed at improving microbial survival and activity under stressful conditions. It offers the opportunity to reuse the immobilized cells for several fermentation cycles. The present study investigated the use of recycled cells entrapped in calcium-alginate beads and cells adsorbed on corncobs (CC) and oakwood chips (OWC) in subsequent fermentation cycles for balsamic-styled vinegar (BSV) production. Sugars, pH, alcohol and total acidity were monitored during fermentation. Microbial activity and product formation declined when immobilized cells were reused for the second cycle for CC and OWC fermentations. Recycled cells entrapped in Ca-alginate beads completed the second cycle of fermentations, albeit at reduced acetification rates compared to the first cycle. Scanning electron microscope (SEM) imaging results further showed a substantial the structural integrity loss for Ca-alginate beads after the first cycle, and with minor changes in the structural integrity of CC. The OWC displayed a similar morphological structure before and after the first cycle. The sensory results showed that BSV produced using immobilized cells with Ca-alginate beads and CC was palatable, while those produced using OWC had negative attributes. Ca-alginate beads offered better protection for the fermentation consortium for culture reusability in BSV fermentations.
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Claes A, Deparis Q, Foulquié-Moreno MR, Thevelein JM. Simultaneous secretion of seven lignocellulolytic enzymes by an industrial second-generation yeast strain enables efficient ethanol production from multiple polymeric substrates. Metab Eng 2020; 59:131-141. [DOI: 10.1016/j.ymben.2020.02.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/01/2020] [Accepted: 02/18/2020] [Indexed: 01/22/2023]
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Smekenov I, Bakhtambayeva M, Bissenbayev K, Saparbayev M, Taipakova S, Bissenbaev AK. Heterologous secretory expression of β-glucosidase from Thermoascus aurantiacus in industrial Saccharomyces cerevisiae strains. Braz J Microbiol 2019; 51:107-123. [PMID: 31776864 DOI: 10.1007/s42770-019-00192-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 11/14/2019] [Indexed: 10/25/2022] Open
Abstract
The use of plant biomass for biofuel production will require efficient utilization of the sugars in lignocellulose, primarily cellobiose, because it is the major soluble by-product of cellulose and acts as a strong inhibitor, especially for cellobiohydrolase, which plays a key role in cellulose hydrolysis. Commonly used ethanologenic yeast Saccharomyces cerevisiae is unable to utilize cellobiose; accordingly, genetic engineering efforts have been made to transfer β-glucosidase genes enabling cellobiose utilization. Nonetheless, laboratory yeast strains have been employed for most of this research, and such strains may be difficult to use in industrial processes because of their generally weaker resistance to stressors and worse fermenting abilities. The purpose of this study was to engineer industrial yeast strains to ferment cellobiose after stable integration of tabgl1 gene that encodes a β-glucosidase from Thermoascus aurantiacus (TaBgl1). The recombinant S. cerevisiae strains obtained in this study secrete TaBgl1, which can hydrolyze cellobiose and produce ethanol. This study clearly indicates that the extent of glycosylation of secreted TaBgl1 depends from the yeast strains used and is greatly influenced by carbon sources (cellobiose or glucose). The recombinant yeast strains showed high osmotolerance and resistance to various concentrations of ethanol and furfural and to high temperatures. Therefore, these yeast strains are suitable for ethanol production processes with saccharified lignocellulose.
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Affiliation(s)
- Izat Smekenov
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040
| | - Marzhan Bakhtambayeva
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040
| | - Kudaybergen Bissenbayev
- Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040.,Nazarbayev Intellectual School, Almaty, Kazakhstan, 050044
| | - Murat Saparbayev
- Gustave Roussy Cancer Campus, CNRS UMR8200, Université Paris-Sud, F-94805, Villejuif Cedex, France
| | - Sabira Taipakova
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040.,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040
| | - Amangeldy K Bissenbaev
- Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040. .,Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty, Kazakhstan, 050040.
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Aeration, Agitation and Cell Immobilization on Corncobs and Oak Wood Chips Effects on Balsamic-Styled Vinegar Production. Foods 2019; 8:foods8080303. [PMID: 31374870 PMCID: PMC6723862 DOI: 10.3390/foods8080303] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 07/19/2019] [Accepted: 07/22/2019] [Indexed: 11/16/2022] Open
Abstract
Optimum fermentor conditions are essential for desired microbial growth and activity in fermentations. In balsamic vinegar fermentation systems, the microorganisms used must endure several stressful conditions including high sugar concentration, low water activity, high osmotic pressure and high acetic acid concentration. Consequently, the present study was aimed at improving the performance of a microbial consortium of non-Saccharomyces yeast and acetic acid bacteria during balsamic-styled vinegar fermentation. Cell immobilization via adsorption on corncobs and oak wood chips in combination with aeration and agitation effects, have never been tested during balsamic-styled vinegar fermentation. Therefore, fermentations were initially conducted under static conditions without aeration with successive fermentations also being subjected to low (0.15 vvm min-1) and high (0.3 vvm min-1) aeration. The results showed improved acetification rates when cells were immobilized on corncobs under static conditions. Low aeration showed better acetification rates (1.45-1.56 g·L·day-1), while only free-floating cells were able to complete fermentations (1.2 g·L·day-1) under high aeration conditions. Overall, cells immobilized on corncobs showed higher acetification rates of 1.56 and 2.7 g·L·day-1 under low aeration and static fermentations, respectively. Oak wood chips were determined to be less efficient adsorbents due to their relatively smooth surface, while the rough surface and porosity of corncobs led to improved adsorption and, therefore, enhanced acetification rates.
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Kao MR, Kuo HW, Lee CC, Huang KY, Huang TY, Li CW, Chen CW, Wang AHJ, Yu SM, Ho THD. Chaetomella raphigera β-glucosidase D2-BGL has intriguing structural features and a high substrate affinity that renders it an efficient cellulase supplement for lignocellulosic biomass hydrolysis. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:258. [PMID: 31700541 PMCID: PMC6825360 DOI: 10.1186/s13068-019-1599-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 10/22/2019] [Indexed: 05/17/2023]
Abstract
BACKGROUND To produce second-generation biofuels, enzymatic catalysis is required to convert cellulose from lignocellulosic biomass into fermentable sugars. β-Glucosidases finalize the process by hydrolyzing cellobiose into glucose, so the efficiency of cellulose hydrolysis largely depends on the quantity and quality of these enzymes used during saccharification. Accordingly, to reduce biofuel production costs, new microbial strains are needed that can produce highly efficient enzymes on a large scale. RESULTS We heterologously expressed the fungal β-glucosidase D2-BGL from a Taiwanese indigenous fungus Chaetomella raphigera in Pichia pastoris for constitutive production by fermentation. Recombinant D2-BGL presented significantly higher substrate affinity than the commercial β-glucosidase Novozyme 188 (N188; K m = 0.2 vs 2.14 mM for p-nitrophenyl β-d-glucopyranoside and 0.96 vs 2.38 mM for cellobiose). When combined with RUT-C30 cellulases, it hydrolyzed acid-pretreated lignocellulosic biomasses more efficiently than the commercial cellulase mixture CTec3. The extent of conversion from cellulose to glucose was 83% for sugarcane bagasse and 63% for rice straws. Compared to N188, use of D2-BGL halved the time necessary to produce maximal levels of ethanol by a semi-simultaneous saccharification and fermentation process. We upscaled production of recombinant D2-BGL to 33.6 U/mL within 15 days using a 1-ton bioreactor. Crystal structure analysis revealed that D2-BGL belongs to glycoside hydrolase (GH) family 3. Removing the N-glycosylation N68 or O-glycosylation T431 residues by site-directed mutagenesis negatively affected enzyme production in P. pastoris. The F256 substrate-binding residue in D2-BGL is located in a shorter loop surrounding the active site pocket relative to that of Aspergillus β-glucosidases, and this short loop is responsible for its high substrate affinity toward cellobiose. CONCLUSIONS D2-BGL is an efficient supplement for lignocellulosic biomass saccharification, and we upscaled production of this enzyme using a 1-ton bioreactor. Enzyme production could be further improved using optimized fermentation, which could reduce biofuel production costs. Our structure analysis of D2-BGL offers new insights into GH3 β-glucosidases, which will be useful for strain improvements via a structure-based mutagenesis approach.
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Affiliation(s)
- Mu-Rong Kao
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and National Defense Medical Center, Taipei, Taiwan, ROC
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Hsion-Wen Kuo
- Department of Environmental Science and Engineering, Tunghai University, Taichung, Taiwan, ROC
| | - Cheng-Chung Lee
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan, ROC
| | - Kuan-Ying Huang
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - Ting-Yen Huang
- Department of Bioengineering, Tatung University, Taipei, Taiwan, ROC
| | - Chen-Wei Li
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
| | - C. Will Chen
- Department of Bioengineering, Tatung University, Taipei, Taiwan, ROC
| | | | - Su-May Yu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan, ROC
- Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
| | - Tuan-Hua David Ho
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan, ROC
- Biotechnology Center, National Chung Hsing University, Taichung, Taiwan, ROC
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Geberekidan M, Zhang J, Liu ZL, Bao J. Improved cellulosic ethanol production from corn stover with a low cellulase input using a β-glucosidase-producing yeast following a dry biorefining process. Bioprocess Biosyst Eng 2018; 42:297-304. [PMID: 30411143 DOI: 10.1007/s00449-018-2034-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Accepted: 10/31/2018] [Indexed: 11/26/2022]
Abstract
A low-cost and sustainable cellulosic ethanol production is vital for fermentation-based industrial applications. Reducing the expenses of cellulose-deconstruction enzymes is one of the significant challenges to economic cellulose-to-ethanol conversion. Here, we report the improved ethanol production from corn stover after dry biorefining using a natural β-glucosidase-producing strain Clavispora NRRL Y-50464 with a low cellulase dose of 5 mg protein/g glucan under separate enzymatic hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) conditions. Strain Clavispora NRRL Y-50464 exhibited a superior ethanol fermentation performance over Saccharomyces cerevisiae DQ1 under both conditions. It produced an ethanol titer of 38.1 g/L within 96 h at a conversion efficiency of 55.5% with 25% solids loading (w/w) via SSF without addition of extra β-glucosidase supplement. Improved performance of Y-50464 on a bioreactor with a helical stirring apparatus confirmed its advantage over the conventional bioreactors originally designed for liquid fermentations in cellulosic ethanol conversion by SSF. The results of this study suggested that the strain Clavispora NRRL Y-50464 has a potential as a candidate for lower-cost cellulosic ethanol production from lignocellulosic materials.
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Affiliation(s)
- Mesfin Geberekidan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
| | - Jian Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China.
| | - Z Lewis Liu
- Bioenergy Research Unit, National Center for Agricultural Utilization Research, USDA-ARS, Peoria, IL, 61604, USA.
| | - Jie Bao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, China
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KRAIEM TESNIM, BARKAOUI ABDELWAHED, MERZOUKI TAREK, CHAFRA MOEZ. CROSS-LINKS MULTISCALE EFFECTS ON BONE ULTRASTRUCTURE BIOMECHANICAL BEHAVIOR. J MECH MED BIOL 2018. [DOI: 10.1142/s0219519418500628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Bone is a multiscale combination of collagen molecules merged with mineral crystals. Its high rigidity and stability stem amply from its polymeric organic matrix and secondly from the connections established between interdifferent and intradifferent scale components through cross-links. Several studies have shown that the cross-links inhibition results in a reduction in strength of bone but they do not quantify the degree to which these connections contribute to the bone rigidity and toughness. This report is classified among the few works that measure the cross-links multiscale impact on the ultrastructure bone mechanical behavior. This work aims firstly to study the effect of cross-links at the molecule scale and secondly to gather from literature studies results handling with cross-links effects on the other bone ultrastructure scales in order to reveal the multiscale effect of cross-links. This study proves that cross-links increasing number improves the mechanical performance of each scale of bone ultrastructure. On the other hand, cross-links have a multiscale contribution that depends on its rank related to existing cross-links connecting the same geometries and it depends on mechanical characteristics of geometries connected.
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Affiliation(s)
- TESNIM KRAIEM
- LR-11-ES19 Laboratoire de Mécanique Appliquée et Ingénierie (LR-MAI), Ecole Nationale d’Ingénieurs de Tunis, Université de Tunis El Manar 1002, Tunis, Tunisia
| | - ABDELWAHED BARKAOUI
- Laboratoire des Energies Renouvelables et Matériaux Avancés (LERMA), Ecole Supérieure de l’Ingénierie de l’Energie, Université Internationale de Rabat, Rocade RabatSalé, 11100, Rabat-Sala El Jadida, Morocco
| | - TAREK MERZOUKI
- Laboratoire d’Ingénierie des Systèmes de Versailles LISV, Université of Versailles Saint-Quentin 10-12 avenue, de l’Europe, 78140 Vélisy, France
| | - MOEZ CHAFRA
- Laboratoire de Systèmes et de Mécanique Appliquée (LASMAP), Ecole Polytechnique de Tunis, Université de Carthage, 2078, La Marsa, Tunisia
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Xia Y, Yang L, Xia L. High-level production of a fungal β-glucosidase with application potentials in the cost-effective production of Trichoderma reesei cellulase. Process Biochem 2018. [DOI: 10.1016/j.procbio.2018.03.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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10
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Liu H, Sun J, Chang JS, Shukla P. Engineering microbes for direct fermentation of cellulose to bioethanol. Crit Rev Biotechnol 2018; 38:1089-1105. [DOI: 10.1080/07388551.2018.1452891] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Hao Liu
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China
| | - Jianliang Sun
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China
| | - Jo-Shu Chang
- Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan, China
| | - Pratyoosh Shukla
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, India
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Xu Y, Ye BC. GlnR and PhoP regulate β-glucosidases involved in cellulose digestion in response to nitrogen and phosphate availability. MICROBIOLOGY-SGM 2018; 164:779-789. [PMID: 29583114 DOI: 10.1099/mic.0.000654] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The limited catalytic efficiency of cellulose-degrading enzymes restricts cellulose digestion. We investigated the transcriptional regulation of genes encoding key cellulose degrading enzymes, namely β-glucosidases, in the industrial actinobacterium Saccharopolyspora erythraea. We observed that the expression of most β-glucosidase-encoding genes was controlled by the availability of nitrogen and phosphate via their respective global regulators, namely GlnR and PhoP. Electrophoretic mobility shift assay demonstrated that GlnR and PhoP bound directly to the promoters of β-glucosidase-encoding genes. Deletion of glnR resulted in lower transcript levels and activity of β-glucosidases, leading to decreased bacterial growth on cellulose. Overexpression of glnR and phoP or nitrogen/phosphate starvation increased the transcript levels and total activity of β-glucosidases. Moreover, GlnR/PhoP-mediated cellobiose utilization was also observed in Streptomyces coelicolor A3(2). These findings provide insights into the regulatory roles played by GlnR and PhoP in coordinating nitrogen/phosphate metabolism and carbohydrate utilization, and indicate potential strategies for cellulose fermentation in the production of bio-based chemicals by actinobacteria.
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Affiliation(s)
- Ya Xu
- Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, PR China
| | - Bang-Ce Ye
- Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, PR China.,Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, PR China
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Singhania RR, Patel AK, Pandey A, Ganansounou E. Genetic modification: A tool for enhancing beta-glucosidase production for biofuel application. BIORESOURCE TECHNOLOGY 2017; 245:1352-1361. [PMID: 28596076 DOI: 10.1016/j.biortech.2017.05.126] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 05/17/2017] [Accepted: 05/19/2017] [Indexed: 05/25/2023]
Abstract
Beta-glucosidase (BGL) is a rate-limiting enzyme for cellulose hydrolysis as it acts in the final step of lignocellulosic biomass conversion to convert cellobiose into glucose, the final end product. Most of the fungal strains used for cellulase production are deficient in BGL hence BGL is supplemented into cellulases to have an efficient biomass conversion. Genetic engineering has enabled strain modification to produce BGL optimally with desired properties to be employed for biofuel applications. It has been cloned either directly into the host strains lacking BGL or into another expression system, to be overexpressed so as to be blended into BGL deficient cellulases. In this article, role of genetic engineering to overcome BGL limitations in the cellulase cocktail and its significance for biofuel applications has been critically reviewed.
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Affiliation(s)
- Reeta Rani Singhania
- DBT-IOC Advanced Bio-Energy Research Centre, Indian Oil Corporation; R&D Centre, Sector-13, Faridabad 121007, India
| | - Anil Kumar Patel
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu 96822, HI, United States.
| | - Ashok Pandey
- Center of Innovative and Applied Bioprocessing, Sector 81, Knowledge City PO Manauli, SAS Nagar, Mohali 140306, Punjab, India
| | - Edgard Ganansounou
- Bioenergy and Energy Planning Research Group, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
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Direct bioethanol production from wheat straw using xylose/glucose co-fermentation by co-culture of two recombinant yeasts. ACTA ACUST UNITED AC 2017; 44:453-464. [DOI: 10.1007/s10295-016-1893-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 12/22/2016] [Indexed: 10/20/2022]
Abstract
Abstract
To achieve a cost-effective bioconversion of lignocellulosic materials, a novel xylose/glucose co-fermentation process by co-culture of cellulose-utilizing recombinant Saccharomyces cerevisiae (S. cerevisiae) and xylan-utilizing recombinant Pichia pastoris (P. pastoris) was developed, in which ethanol was produced directly from wheat straw without additional hydrolytic enzymes. Recombinant S. cerevisiae coexpressing three types of cellulase and recombinant P. pastoris coexpressing two types of xylanase were constructed, respectively. All cellulases and xylanases were successfully expressed and similar extracellular activity was demonstrated. The maximum ethanol concentration of 32.6 g L−1 with the yield 0.42 g g−1 was achieved from wheat straw corresponding to 100 g L−1 of total sugar after 80 h co-fermentation, which corresponds to 82.6% of the theoretical yield. These results demonstrate that the direct and efficient ethanol production from lignocellulosic materials is accomplished by simultaneous saccharification (cellulose and hemicellulose) and co-fermentation (glucose and xylose) with the co-culture of the two recombinant yeasts.
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14
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Production of ethanol from steam exploded triticale straw in a simultaneous saccharification and fermentation process. Process Biochem 2017. [DOI: 10.1016/j.procbio.2016.11.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Expression of a codon-optimized β-glucosidase from Cellulomonas flavigena PR-22 in Saccharomyces cerevisiae for bioethanol production from cellobiose. Arch Microbiol 2017; 199:605-611. [DOI: 10.1007/s00203-016-1333-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 12/13/2016] [Accepted: 12/26/2016] [Indexed: 10/20/2022]
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16
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Wang J, Ma Y, Zhang K, Yang H, Liu C, Zou S, Hong J, Zhang M. Mating type and ploidy effect on the β-glucosidase activity and ethanol-producing performance of Saccharomyces cerevisiae with multiple δ-integrated bgl 1 gene. J Biotechnol 2016; 231:24-31. [DOI: 10.1016/j.jbiotec.2016.05.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 05/20/2016] [Accepted: 05/20/2016] [Indexed: 11/15/2022]
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17
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Heterologously expressed Aspergillus aculeatus β-glucosidase in Saccharomyces cerevisiae is a cost-effective alternative to commercial supplementation of β-glucosidase in industrial ethanol production using Trichoderma reesei cellulases. J Biosci Bioeng 2016; 121:27-35. [DOI: 10.1016/j.jbiosc.2015.05.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 05/07/2015] [Accepted: 05/08/2015] [Indexed: 11/17/2022]
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18
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L. Herring J, C. Narayanan V. A Comparative Study on the Utilization of Corn Pericarp and Peanut Hull in the Production of Ethanol and the Impact on Food Economics. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/fns.2016.711098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Ma Y, Liu X, Yin Y, Zou C, Wang W, Zou S, Hong J, Zhang M. Expression optimization and biochemical properties of two glycosyl hydrolase family 3 beta-glucosidases. J Biotechnol 2015; 206:79-88. [PMID: 25937452 DOI: 10.1016/j.jbiotec.2015.04.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 03/26/2015] [Accepted: 04/18/2015] [Indexed: 10/23/2022]
Abstract
The β-glucosidases from Saccharomycopsis fibuligera (SfBGL1) and Trichoderma reesei (TrBGL1) were cloned and expressed in Pichia pastoris. Methanol concentration and pH significantly affected the production. The combined effects of the two factors were optimized by using the response surface method, resulting in a 137% and 84% increase in rTrBGL1 and rSfBGL1 yield compared to single-factor experiment. Structure and biochemical properties of the two enzyme were investigated and compared. They belong to glycosyl hydrolase family 3 and exhibit significant hydrolysis activity and low-level transglycosylation activity. The two enzymes show similar substrate affinity and ion-tolerance, and both of them can be activated by Cr(6+), Mn(2+) and Fe(2+). The rSfBGL1 has greater catalytic speed, higher specific activity and acid-tolerance than rTrBGL1, but rTrBGL1 is more thermostable and has higher optimal temperature than rSfBGL1. This study provides a useful and quick optimal method for recombinant enzyme production and makes a valuable comparison of biochemical properties, which opens important avenues of exploration for relationship between structure and function and further practical applications.
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Affiliation(s)
- Yuanyuan Ma
- R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China; Key Laboratory for Green Chemical Technology of Ministry of Education, R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China.
| | - Xuewei Liu
- R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China; Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
| | - Yanchen Yin
- R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China; Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
| | - Chao Zou
- R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China; Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
| | - Wanchao Wang
- R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China; Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
| | - Shaolan Zou
- R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China; Key Laboratory for Green Chemical Technology of Ministry of Education, R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China.
| | - Jiefang Hong
- R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China.
| | - Minhua Zhang
- R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China; Key Laboratory for Green Chemical Technology of Ministry of Education, R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China.
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Guo H, Zou S, Liu B, Su R, Huang R, Qi W, Zhang M, He Z. Reducing β-glucosidase supplementation during cellulase recovery using engineered strain for successive lignocellulose bioconversion. BIORESOURCE TECHNOLOGY 2015; 187:362-368. [PMID: 25863900 DOI: 10.1016/j.biortech.2015.03.105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Revised: 03/21/2015] [Accepted: 03/23/2015] [Indexed: 06/04/2023]
Abstract
Enzyme recycling by re-adsorption is one of the primary methods for reducing enzyme usage in lignocellulose conversion. This work proposes the combination of an engineered yeast strain that expresses β-glucosidase with enzyme recycling to reduce the amount of supplemented β-glucosidase in enzyme recycling experiments. Using the engineered strain, a slight increase in ethanol concentration was obtained after a 96-h fermentation of pretreated corncobs. Ethanol concentrations increased by 34.7% and 62.7% in the following two recycle rounds using the engineered strain compared with those using its parental strain without β-glucosidase addition. Furthermore, with the addition of β-glucosidase at 30CBU/g cellulose, the ethanol concentration after two recycle rounds exceeded 90% of that observed in the first SSF round with the engineered strain at a high initial cellulase loading of 45FPU/g cellulose.
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Affiliation(s)
- Hong Guo
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Shaolan Zou
- Tianjin R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China
| | - Boshi Liu
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Rongxin Su
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China.
| | - Renliang Huang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Wei Qi
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China
| | - Minhua Zhang
- Tianjin R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China; Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China.
| | - Zhimin He
- State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
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Guo Z, Duquesne S, Bozonnet S, Cioci G, Nicaud JM, Marty A, O’Donohue MJ. Development of cellobiose-degrading ability in Yarrowia lipolytica strain by overexpression of endogenous genes. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:109. [PMID: 26244054 PMCID: PMC4524412 DOI: 10.1186/s13068-015-0289-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 07/22/2015] [Indexed: 05/03/2023]
Abstract
BACKGROUND Yarrowia lipolytica, one of the most widely studied "nonconventional" oleaginous yeast species, is unable to grow on cellobiose. Engineering cellobiose-degrading ability into this yeast is a vital step towards the development of cellulolytic biocatalysts suitable for consolidated bioprocessing. RESULTS In the present work, we identified six genes encoding putative β-glucosidases in the Y. lipolytica genome. To study these, homologous expression was attempted in Y. lipolytica JMY1212 Zeta. Two strains overexpressing BGL1 (YALI0F16027g) and BGL2 (YALI0B14289g) produced β-glucosidase activity and were able to degrade cellobiose, while the other four did not display any detectable activity. The two active β-glucosidases, one of which was mainly cell-associated while the other was present in the extracellular medium, were purified and characterized. The two Bgls were most active at 40-45°C and pH 4.0-4.5, and exhibited hydrolytic activity on various β-glycoside substrates. Specifically, Bgl1 displayed 12.5-fold higher catalytic efficiency on cellobiose than Bgl2. Significantly, in experiments where cellobiose or cellulose (performed in the presence of a β-glucosidase-deficient commercial cellulase cocktail produced by Trichoderma reseei) was used as carbon source for aerobic cultivation, Y. lipolytica ∆pox co-expressing BGL1 and BGL2 grew better than the Y. lipolytica strains expressing single BGLs. The specific growth rate and biomass yield of Y. lipolytica JMY1212 co-expressing BGL1 and BGL2 were 0.15 h(-1) and 0.50 g-DCW/g-cellobiose, respectively, similar to that of the control grown on glucose. CONCLUSIONS We conclude that the bi-functional Y. lipolytica developed in the current study represents a vital step towards the creation of a cellulolytic yeast strain that can be used for lipid production from lignocellulosic biomass. When used in combination with commercial cellulolytic cocktails, this strain will no doubt reduce enzyme requirements and thus costs.
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Affiliation(s)
- Zhongpeng Guo
- />LISBP-Biocatalysis Group, INSA/INRA UMR 792, Université de Toulouse, 135 Avenue de Rangueil, 31077 Toulouse, France
- />INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, 31400 Toulouse, France
- />CNRS, UMR5504, 31400 Toulouse, France
| | - Sophie Duquesne
- />LISBP-Biocatalysis Group, INSA/INRA UMR 792, Université de Toulouse, 135 Avenue de Rangueil, 31077 Toulouse, France
- />INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, 31400 Toulouse, France
- />CNRS, UMR5504, 31400 Toulouse, France
| | - Sophie Bozonnet
- />LISBP-Biocatalysis Group, INSA/INRA UMR 792, Université de Toulouse, 135 Avenue de Rangueil, 31077 Toulouse, France
- />INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, 31400 Toulouse, France
- />CNRS, UMR5504, 31400 Toulouse, France
| | - Gianluca Cioci
- />LISBP-Biocatalysis Group, INSA/INRA UMR 792, Université de Toulouse, 135 Avenue de Rangueil, 31077 Toulouse, France
- />INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, 31400 Toulouse, France
- />CNRS, UMR5504, 31400 Toulouse, France
| | - Jean-Marc Nicaud
- />INRA, UMR1319 Micalis, 78352 Jouy-en-Josas, France
- />AgroParisTech, UMR Micalis, 78352 Jouy-en-Josas, France
| | - Alain Marty
- />LISBP-Biocatalysis Group, INSA/INRA UMR 792, Université de Toulouse, 135 Avenue de Rangueil, 31077 Toulouse, France
- />INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, 31400 Toulouse, France
- />CNRS, UMR5504, 31400 Toulouse, France
| | - Michael Joseph O’Donohue
- />LISBP-Biocatalysis Group, INSA/INRA UMR 792, Université de Toulouse, 135 Avenue de Rangueil, 31077 Toulouse, France
- />INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, 31400 Toulouse, France
- />CNRS, UMR5504, 31400 Toulouse, France
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Xu L, Shen Y, Hou J, Peng B, Tang H, Bao X. Secretory pathway engineering enhances secretion of cellobiohydrolase I from Trichoderma reesei in Saccharomyces cerevisiae. J Biosci Bioeng 2014; 117:45-52. [DOI: 10.1016/j.jbiosc.2013.06.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 05/27/2013] [Accepted: 06/16/2013] [Indexed: 10/26/2022]
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23
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Mendoza-Aguayo DJ, Poggi-Varaldo HM, García-Mena J, Ramos-Valdivia AC, Salgado LM, de la Torre-Martínez M, Ponce-Noyola T. Extracellular expression of glucose inhibition-resistant Cellulomonas flavigena PN-120 β-glucosidase by a diploid strain of Saccharomyces cerevisiae. Arch Microbiol 2013; 196:25-33. [DOI: 10.1007/s00203-013-0935-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 10/16/2013] [Accepted: 10/23/2013] [Indexed: 11/30/2022]
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24
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Analysis of cellodextrin transporters from Neurospora crassa in Saccharomyces cerevisiae for cellobiose fermentation. Appl Microbiol Biotechnol 2013; 98:1087-94. [DOI: 10.1007/s00253-013-5339-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 10/15/2013] [Accepted: 10/16/2013] [Indexed: 11/25/2022]
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25
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Lee WH, Nan H, Kim HJ, Jin YS. Simultaneous saccharification and fermentation by engineered Saccharomyces cerevisiae without supplementing extracellular β-glucosidase. J Biotechnol 2013; 167:316-22. [DOI: 10.1016/j.jbiotec.2013.06.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 06/26/2013] [Accepted: 06/27/2013] [Indexed: 10/26/2022]
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26
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Recent progress in metabolic engineering for the production of biofuels and biochemicals from renewable sources with particular emphasis on catabolite regulation and its modulation. Process Biochem 2013. [DOI: 10.1016/j.procbio.2013.02.032] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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27
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Wang G, Liu C, Hong J, Ma Y, Zhang K, Huang X, Zou S, Zhang M. Comparison of process configurations for ethanol production from acid- and alkali-pretreated corncob by Saccharomyces cerevisiae strains with and without β-glucosidase expression. BIORESOURCE TECHNOLOGY 2013; 142:154-161. [PMID: 23735797 DOI: 10.1016/j.biortech.2013.05.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 05/07/2013] [Accepted: 05/08/2013] [Indexed: 06/02/2023]
Abstract
β-Glucosidase was shown to have synergistic effects with commercial cellulase in the hydrolysis of acid- and alkali-pretreated corncob, especially at the dose of 5 U/g biomass and 5 or 10 FPU/g biomass. An integrating yeast strain 45# expressing β-glucosidase was constructed that utilized cellobiose quickly and efficiently. Process configurations were compared under conditions of 10% solid content, 10 FPU cellulase/g biomass, 5 U β-glucosidase/g biomass (only used for parental strain W303-1A), 1g/kg yeast loading and 3.3g/kg urea supplementation. While separate hydrolysis and fermentation was optimal for W303-1A and the ethanol titer and yield reached 3.22 g/100g and 75.6% (expressed as a percentage of the theoretical yield), respectively, simultaneous saccharification and fermentation was optimal for strain 45# and the ethanol titer and yield reached 3.31 g/100g and 77.7%, respectively. These results are valuable in optimization of the process configuration and improving the yeast strain selected for cellulosic ethanol production.
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Affiliation(s)
- Guoqiang Wang
- Tianjin R&D Center for Petrochemical Technology, Tianjin University, Tianjin 300072, China
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28
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Liu G, Qin Y, Li Z, Qu Y. Development of highly efficient, low-cost lignocellulolytic enzyme systems in the post-genomic era. Biotechnol Adv 2013; 31:962-75. [PMID: 23507038 DOI: 10.1016/j.biotechadv.2013.03.001] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 03/09/2013] [Accepted: 03/10/2013] [Indexed: 11/19/2022]
Abstract
The current high cost of lignocellulolytic enzymes is a major bottleneck in the economic bioconversion of lignocellulosic biomass to fuels and chemicals. Fungal lignocellulolytic enzyme systems are secreted at high levels, making them the most promising starting points for further development of highly efficient lignocellulolytic enzyme systems. In this paper, recent advances in improvement of fungal lignocellulolytic enzyme systems are reviewed, with an emphasis on the achievements made using genomic approaches. A general strategy for lignocellulolytic enzyme system development is proposed, including the improvement of the hydrolysis efficiencies and productivities of current enzyme systems. The applications of genomic, transcriptomic and proteomic analysis methods in examining the composition of native enzyme systems, discovery of novel enzymes and synergistic proteins from natural sources, and understanding of regulatory mechanisms for lignocellulolytic enzyme biosynthesis are summarized. By combining systems biology and synthetic biology tools, engineered fungal strains are expected to produce high levels of optimized lignocellulolytic enzyme systems.
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Affiliation(s)
- Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China
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29
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Liu G, Zhang L, Wei X, Zou G, Qin Y, Ma L, Li J, Zheng H, Wang S, Wang C, Xun L, Zhao GP, Zhou Z, Qu Y. Genomic and secretomic analyses reveal unique features of the lignocellulolytic enzyme system of Penicillium decumbens. PLoS One 2013; 8:e55185. [PMID: 23383313 PMCID: PMC3562324 DOI: 10.1371/journal.pone.0055185] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 12/19/2012] [Indexed: 02/06/2023] Open
Abstract
Many Penicillium species could produce extracellular enzyme systems with good lignocellulose hydrolysis performance. However, these species and their enzyme systems are still poorly understood and explored due to the lacking of genetic information. Here, we present the genomic and secretomic analyses of Penicillium decumbens that has been used in industrial production of lignocellulolytic enzymes in China for more than fifteen years. Comparative genomics analysis with the phylogenetically most similar species Penicillium chrysogenum revealed that P. decumbens has evolved with more genes involved in plant cell wall degradation, but fewer genes in cellular metabolism and regulation. Compared with the widely used cellulase producer Trichoderma reesei, P. decumbens has a lignocellulolytic enzyme system with more diverse components, particularly for cellulose binding domain-containing proteins and hemicellulases. Further, proteomic analysis of secretomes revealed that P. decumbens produced significantly more lignocellulolytic enzymes in the medium with cellulose-wheat bran as the carbon source than with glucose. The results expand our knowledge on the genetic information of lignocellulolytic enzyme systems in Penicillium species, and will facilitate rational strain improvement for the production of highly efficient enzyme systems used in lignocellulose utilization from Penicillium species.
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Affiliation(s)
- Guodong Liu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, China
| | - Lei Zhang
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Xiaomin Wei
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, China
| | - Gen Zou
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yuqi Qin
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, China
- National Glycoengineering Research Center, Shandong University, Jinan, Shandong, China
| | - Liang Ma
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Jie Li
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, China
| | - Huajun Zheng
- Shanghai-MOST Key Laboratory of Disease and Health Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Shengyue Wang
- Shanghai-MOST Key Laboratory of Disease and Health Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Chengshu Wang
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Luying Xun
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, China
- School of Molecular Biosciences, Washington State University, Pullman, Washington, United States of America
| | - Guo-Ping Zhao
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
- Shanghai-MOST Key Laboratory of Disease and Health Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Zhihua Zhou
- Key Laboratory of Synthetic Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, China
- National Glycoengineering Research Center, Shandong University, Jinan, Shandong, China
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30
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Singhania RR, Patel AK, Sukumaran RK, Larroche C, Pandey A. Role and significance of beta-glucosidases in the hydrolysis of cellulose for bioethanol production. BIORESOURCE TECHNOLOGY 2013; 127:500-7. [PMID: 23069613 DOI: 10.1016/j.biortech.2012.09.012] [Citation(s) in RCA: 320] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Revised: 09/05/2012] [Accepted: 09/05/2012] [Indexed: 05/02/2023]
Abstract
One of the major challenges in the bioconversion of lignocellulosic biomass into liquid biofuels includes the search for a glucose tolerant beta-gulucosidase. Beta-glucosidase is the key enzyme component present in cellulase and completes the final step during cellulose hydrolysis by converting the cellobiose to glucose. This reaction is always under control as it gets inhibited by its product glucose. It is a major bottleneck in the efficient biomass conversion by cellulase. To circumvent this problem several strategies have been adopted which we have discussed in the article along with its production strategies and general properties. It plays a very significant role in bioethanol production from biomass through enzymatic route. Hence several amendments took place in the commercial preparation of cellulase for biomass hydrolysis, which contains higher and improved beta-glucosidase for efficient biomass conversion. This article presents beta-glucosidase as the key component for bioethanol from biomass through enzymatic route.
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Affiliation(s)
- Reeta Rani Singhania
- Laboratoire de Génie Chimique et Biochimique, Université Blaise Pascal, Polytech Clermont-Ferrand, Aubiere cedex, France.
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31
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Huang X, Zhao Y, Dai Y, Wu G, Shao Z, Zeng Q, liu Z. Cloning and biochemical characterization of a glucosidase from a marine bacterium Aeromonas sp. HC11e-3. World J Microbiol Biotechnol 2012; 28:3337-44. [DOI: 10.1007/s11274-012-1145-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 08/02/2012] [Indexed: 11/30/2022]
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32
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Huang Z, Tan Y, Zhang Y, Liu X, Hu H, Qin Y, Huang H. Direct production of cellulose laurate by mechanical activation-strengthened solid phase synthesis. BIORESOURCE TECHNOLOGY 2012; 118:624-627. [PMID: 22683327 DOI: 10.1016/j.biortech.2012.05.082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Revised: 05/15/2012] [Accepted: 05/17/2012] [Indexed: 06/01/2023]
Abstract
This work reports that cellulose laurate could be directly produced by mechanical activation-strengthened solid phase synthesis (MASPS) in a customized stirring mill with using bagasse pulp and lauric acid as materials in an environmentally friendly way. Cellulose laurates with different degree of substitution were obtained under different synthesis conditions without the use of organic co-reagents and solvents. The characterization results showed that cellulose laurates had great changes in surface morphologies and crystal structures compared with bagasse pulp because of the intense milling and introduction of laurate groups, but still retained the cellulose I crystalline form of the native cellulose. MASPS could be considered as a simple, efficient and green method for the production of long chain cellulose esters.
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Affiliation(s)
- Zuqiang Huang
- School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, PR China.
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33
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Fox JM, Levine SE, Blanch HW, Clark DS. An evaluation of cellulose saccharification and fermentation with an engineered Saccharomyces cerevisiae capable of cellobiose and xylose utilization. Biotechnol J 2012; 7:361-73. [DOI: 10.1002/biot.201100209] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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34
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Deng Y, Li S, Xu Q, Gao M, Huang H. Production of fumaric acid by simultaneous saccharification and fermentation of starchy materials with 2-deoxyglucose-resistant mutant strains of Rhizopus oryzae. BIORESOURCE TECHNOLOGY 2012; 107:363-367. [PMID: 22217732 DOI: 10.1016/j.biortech.2011.11.117] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 11/26/2011] [Accepted: 11/26/2011] [Indexed: 05/31/2023]
Abstract
A mutant strain with high glucoamylase activity and insensitive to catabolite repression was developed to produce fumaric acid by simultaneous saccharification and fermentation (SSF) of starch without additional commercial glucoamylase supplementation. A series of mutant strains resistant to the non-metabolizable and toxic glucose analog 2-deoxyglucose (2-DG) were obtained by implanting nitrogen ion (N(+)) into Rhizopus oryzae ME-F12. Among them, the best mutant strain DG-3 produced 39.80 g/L fumaric acid, which is 1.28-fold of that produced by ME-F12, and exhibited higher glucoamylase activity during SSF. Higher fumaric acid production (44.10 g/L) was achieved when the initial total sugar concentration of cornstarch was 100g/L. During SSF of cheap, raw bioresource-degermed corn powder (100g/L total sugar) by DG-3, the maximum fumaric acid concentration and productivity were 32.18 g/L and 0.44 g/(Lh), respectively.
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Affiliation(s)
- Yuefang Deng
- State Key Laboratory of Material-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, No. 5 Xinmofan Road, Nanjing 210009, PR China
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35
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Cellulolytic Enzyme Production and Enzymatic Hydrolysis for Second-Generation Bioethanol Production. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2012; 128:1-24. [DOI: 10.1007/10_2011_131] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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36
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Liu ZL, Weber SA, Cotta MA, Li SZ. A new β-glucosidase producing yeast for lower-cost cellulosic ethanol production from xylose-extracted corncob residues by simultaneous saccharification and fermentation. BIORESOURCE TECHNOLOGY 2012; 104:410-6. [PMID: 22133603 DOI: 10.1016/j.biortech.2011.10.099] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Revised: 10/26/2011] [Accepted: 10/28/2011] [Indexed: 05/24/2023]
Abstract
This study reports a new yeast strain of Clavispora NRRL Y-50464 that is able to utilize cellobiose as sole source of carbon and produce sufficient native β-glucosidase enzyme activity for cellulosic ethanol production using SSF. In addition, this yeast is tolerant to the major inhibitors derived from lignocellulosic biomass pre-treatment such as 2-furaldehyde (furfural) and 5-(hydroxymethyl)-2-furaldehyde (HMF), and converted furfural into furan methanol in less than 12h and HMF into furan-2,5-dimethanol within 24h in the presence of 15 mM each of furfural and HMF. Using xylose-extracted corncob residue as cellulosic feedstock, an ethanol production of 23 g/l was obtained using 25% solids loading at 37 °C by SSF without addition of exogenous β-glucosidase. Development of this yeast aids renewable biofuels development efforts for economic consolidated SSF bio-processing.
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Affiliation(s)
- Z Lewis Liu
- Bioenergy Research Unit, National Center for Agricultural Utilization Research, USDA-ARS, Peoria, IL 61604, USA.
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37
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Barr CJ, Mertens JA, Schall CA. Critical cellulase and hemicellulase activities for hydrolysis of ionic liquid pretreated biomass. BIORESOURCE TECHNOLOGY 2012; 104:480-5. [PMID: 22154300 DOI: 10.1016/j.biortech.2011.10.101] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 10/27/2011] [Accepted: 10/28/2011] [Indexed: 05/10/2023]
Abstract
Critical cellulase and hemicellulase activities are identified for hydrolysis of ionic liquid (IL) pretreated poplar and switchgrass; hemicellulase rich substrates with largely amorphous cellulose. Enzymes from Aspergillus nidulans were expressed and purified: an endoglucanase (EG) a cellobiohydrolase (CBH), an endoxylanase (EX) and an acetylxylan esterase (AXE). β-Xylosidase (βX) from Selenomonas ruminantium and a commercial β-glucosidase (βG) from Novozyme 188 were admixed with the A. nidulans enzymes. Statistical analysis indicates that βG and βX activities are significant for both glucose and xylose yields for the two substrates. EG is a significant factor for glucan hydrolysis while EX is significant for xylan hydrolysis of the substrates. The CBH, which has activity on crystalline cellulose and negligible activity on amorphous cellulose, was not a significant factor in glucan hydrolysis. EX is significant in glucan hydrolysis for poplar. The addition of AXE significantly improves xylan hydrolysis for poplar but not switchgrass.
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Affiliation(s)
- Christopher J Barr
- Department of Chemical & Environmental Engineering, University of Toledo, 2801 W. Bancroft St., Toledo, OH 43606, USA
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Ethanol production from Kinnow mandarin (Citrus reticulata) peels via simultaneous saccharification and fermentation using crude enzyme produced by Aspergillus oryzae and the thermotolerant Pichia kudriavzevii strain. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0302-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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39
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Lee JW, Zhu JY, Scordia D, Jeffries TW. Evaluation of Ethanol Production from Corncob Using Scheffersomyces (Pichia) stipitis CBS 6054 by Volumetric Scale-up. Appl Biochem Biotechnol 2011; 165:814-22. [DOI: 10.1007/s12010-011-9299-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Accepted: 05/26/2011] [Indexed: 10/18/2022]
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Zhang L, Guo ZP, Hong JH, Ding ZY, Gao ZQ, He ZM, Shi GY. Expressing β-glucosidase from Saccharomycopsis fibuligera in industrial ethanol producing yeast and evaluation of the expressing sufficiency. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0289-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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41
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Abstract
In 2010, our group announced the discovery of two cellodextrin transporter families from the cellulolytic fungus, Neurospora crassa. Furthermore, we demonstrated the utility of these transporters in the production of lignocellulosic biofuels. This discovery was made possible by a decision to systematically study cell wall degradation by N. crassa. The identified transport pathway has opened up a new way of thinking about microbial fermentation of hexoses as well as pentoses derived from plant cell walls. Integrating this pathway with the endogenous metabolism and signaling networks of S. cerevisiae is now a major goal of our group.
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Affiliation(s)
- Jonathan M Galazka
- Department of Molecular and Cell Biology, University of California at Berkeley, USA
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Wang HY, Fan BQ, Li CH, Liu S, Li M. Effects of rhamnolipid on the cellulase and xylanase in hydrolysis of wheat straw. BIORESOURCE TECHNOLOGY 2011; 102:6515-6521. [PMID: 21478013 DOI: 10.1016/j.biortech.2011.02.102] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 02/24/2011] [Accepted: 02/24/2011] [Indexed: 05/30/2023]
Abstract
The effects of biosurfactant rhamnolipid (RL) and chemical surfactant Triton X-100 on the production of cellulases and xylanase from Penicillium expansum (P. expansum) in untreated, acid- and alkali-pretreated wheat straw submerged fermentations were studied, and the influences on the activity and stability of Cellulase R-10 were also investigated. The results showed that RL and Triton X-100 enhanced the activities of cellulases and xylanase to different extents and the stimulatory effects of RL were superior to those of Triton X-100. During the peak enzyme production phase, RL (60 RE mg/l) increased cellulases activities by 25.5-102.9%, in which the raise of the same enzyme in acid-pretreated straw broths was the most. It was found that the reducing sugars by hydrolyzing wheat straw with Cellulase R-100 were not visibly increased after adding RL. However, it distinctly protected Cellulase R-10 from degradation or inactivation, keeping the reducing sugars yield at about 17%.
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Affiliation(s)
- Hong-Yuan Wang
- Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
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Guo ZP, Zhang L, Ding ZY, Gu ZH, Shi GY. Development of an industrial ethanol-producing yeast strain for efficient utilization of cellobiose. Enzyme Microb Technol 2011; 49:105-12. [DOI: 10.1016/j.enzmictec.2011.02.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 02/13/2011] [Accepted: 02/16/2011] [Indexed: 10/18/2022]
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Gurgu L, Lafraya Á, Polaina J, Marín-Navarro J. Fermentation of cellobiose to ethanol by industrial Saccharomyces strains carrying the β-glucosidase gene (BGL1) from Saccharomycopsis fibuligera. BIORESOURCE TECHNOLOGY 2011; 102:5229-36. [PMID: 21324680 DOI: 10.1016/j.biortech.2011.01.062] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 01/18/2011] [Accepted: 01/19/2011] [Indexed: 05/23/2023]
Abstract
Constructs carrying the Saccharomycopsis fibuligera β-glucosidase gene (BGL1) under the control of a constitutive actin or a galactose-inducible promoter were introduced into eleven Saccharomyces strains. In ten of these recombinant strains, BGL1 expression driven by the actin promoter was between 1.6- and 18-fold higher than that obtained with the galactose-inducible promoter. Strains carrying the actin promoter yielded ethanol concentrations from cellobiose of between 0.5% and 14%, depending on their ability to accumulate Bgl1 (between 30 and 250 mU/mL) but also on their genetic background. Comparative analysis of a S. cerevisiae strain and its corresponding petite version showed similar ethanol yields, despite a 3-fold lower β-glucosidase production of the latter, suggesting that respiratory activity could be one of the factors influencing ethanol production when using carbon sources other than glucose. This study provides a selection of strains that may be good candidates as hosts for ethanol biosynthesis from cellulosic substrates.
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Affiliation(s)
- Leontina Gurgu
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, CSIC, Paterna, Valencia, Spain
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Saibi W, Abdeljalil S, Gargouri A. Carbon source directs the differential expression of β-glucosidases in Stachybotrys microspora. World J Microbiol Biotechnol 2011. [DOI: 10.1007/s11274-010-0634-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Oberoi HS, Vadlani PV, Nanjundaswamy A, Bansal S, Singh S, Kaur S, Babbar N. Enhanced ethanol production from Kinnow mandarin (Citrus reticulata) waste via a statistically optimized simultaneous saccharification and fermentation process. BIORESOURCE TECHNOLOGY 2011; 102:1593-1601. [PMID: 20863699 DOI: 10.1016/j.biortech.2010.08.111] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2010] [Revised: 08/29/2010] [Accepted: 08/30/2010] [Indexed: 05/29/2023]
Abstract
Dried, ground, and hydrothermally pretreated Kinnow mandarin (Citrus reticulata) waste was used to produce ethanol via simultaneous saccharification and fermentation (SSF). Central composite design was used to optimize cellulase and pectinase concentrations, temperature, and time for SSF. The D-limonene concentration determined with high-performance liquid chromatography (HPLC) for fresh, dried, and pretreated biomass was 0.76%, 0.32%, and 0.09% (v/w), respectively. Design Expert software suggested that the first-order effect of all four factors and the second-order effect of cellulase and pectinase concentrations were significant for ethanol production. The validation experiment using 6 FPU gds(-1) cellulase and 60 IU gds(-1) pectinase at 37 °C for 12 h in a laboratory batch fermenter resulted in ethanol concentration and productivity of 42 g L(-1) and 3.50 g L(-1) h(-1), respectively. Experiments using optimized parameters resulted in an ethanol concentration similar to that predicted by the model equation and also helped reduce fermentation time.
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Affiliation(s)
- Harinder Singh Oberoi
- Department of Grain Science and Industry, Kansas State University, Manhattan, KS 66506, USA.
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Kitagawa T, Kohda K, Tokuhiro K, Hoshida H, Akada R, Takahashi H, Imaeda T. Identification of genes that enhance cellulase protein production in yeast. J Biotechnol 2010; 151:194-203. [PMID: 21167225 DOI: 10.1016/j.jbiotec.2010.12.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 12/02/2010] [Accepted: 12/07/2010] [Indexed: 10/18/2022]
Abstract
In order to enhance heterologous cellulase protein production in yeast, a plasmid harboring the endoglucanase gene from Clostridium thermocellum (Ctcel8A) was used to systematically transform a homozygous diploid yeast deletion strain collection. We identified 55 deletion strains that exhibited enhanced endoglucanase activity compared with that of the wild-type strain. Genes disrupted in these strains were classified into the categories of transcription, translation, phospholipid synthesis, endosome/vacuole function, ER/Golgi function, nitrogen starvation response, and cytoskeleton. The vps3Δ and vps16Δ strains, which have deletion in genes encoding components of the class C core vacuole/endosome tethering (CORVET) complex, also exhibited enhanced β-glucosidase activity when Ctcel8A was heterologously expressed. Moreover, multiple gene deletion strains were constructed by using the vps3Δ strain. Endoglucanase activity of the resulting rav1Δvps3Δ double deletion strain was exhibited higher than that of the rav1Δ or vps3Δ strains. Our genome-wide analyses using the yeast deletion strain collection identified useful genes that allow efficient expression of cellulase.
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Affiliation(s)
- Takao Kitagawa
- Department of Applied Molecular Bioscience, Yamaguchi University Graduate School of Medicine, Tokiwadai, Ube 755-8611, Japan.
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Marín-Navarro J, Gurgu L, Alamar S, Polaina J. Structural and functional analysis of hybrid enzymes generated by domain shuffling between Saccharomyces cerevisiae (var. diastaticus) Sta1 glucoamylase and Saccharomycopsis fibuligera Bgl1 β-glucosidase. Appl Microbiol Biotechnol 2010; 89:121-30. [DOI: 10.1007/s00253-010-2845-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 08/11/2010] [Accepted: 08/11/2010] [Indexed: 12/01/2022]
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49
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Dilute Acid Pretreatment of Corncob for Efficient Sugar Production. Appl Biochem Biotechnol 2010; 163:658-68. [DOI: 10.1007/s12010-010-9071-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Accepted: 08/16/2010] [Indexed: 11/25/2022]
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50
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Zhang XZ, Zhang YHP. One-step production of biocommodities from lignocellulosic biomass by recombinant cellulolytic Bacillus subtilis: Opportunities and challenges. Eng Life Sci 2010. [DOI: 10.1002/elsc.201000011] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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