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Lee DS, Cho EJ, Nguyen DT, Song Y, Chang J, Bae HJ. Succinic acid production from softwood with genome-edited Corynebacterium glutamicum using the CRISPR-Cpf1 system. Biotechnol J 2024; 19:e2300309. [PMID: 38180273 DOI: 10.1002/biot.202300309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 01/06/2024]
Abstract
Corynebacterium glutamicum is a useful microbe that can be used for producing succinic acid under anaerobic conditions. In this study, we generated a knock-out mutant of the lactate dehydrogenase 1 gene (ΔldhA-6) and co-expressed the succinic acid transporter (Psod:SucE- ΔldhA) using the CRISPR-Cpf1 genome editing system. The highly efficient HPAC (hydrogen peroxide and acetic acid) pretreatment method was employed for the enzymatic hydrolysis of softwood (Pinus densiflora) and subsequently utilized for production of succinic acid. Upon evaluating a 1%-5% hydrolysate concentration range, optimal succinic acid production with the ΔldhA mutant was achieved at a 4% hydrolysate concentration. This resulted in 14.82 g L-1 succinic acid production over 6 h. No production of acetic acid and lactic acid was detected during the fermentation. The co-expression transformant, [Psod:SucE-ΔldhA] produced 17.70 g L-1 succinic acid in 6 h. In the fed-batch system, 39.67 g L-1 succinic acid was produced over 48 h. During the fermentation, the strain consumed 100% and 73% of glucose and xylose, respectively. The yield of succinic acid from the sugars consumed was approximately 0.77 g succinic acid/g sugars. These results indicate that the production of succinic acid from softwood holds potential applications in alternative biochemical processes.
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Affiliation(s)
- Dae-Seok Lee
- Bio-energy Research Institute, Chonnam National University, Gwangju, Republic of Korea
| | - Eun Jin Cho
- Bio-energy Research Institute, Chonnam National University, Gwangju, Republic of Korea
| | | | - Younho Song
- Bio-energy Research Institute, Chonnam National University, Gwangju, Republic of Korea
| | - Jihye Chang
- Department of Bioenergy Science and Technology, Chonnam National University, Gwangju, Republic of Korea
| | - Hyeun-Jong Bae
- Bio-energy Research Institute, Chonnam National University, Gwangju, Republic of Korea
- School of Biotechology, Tan Tao University, Long An, Viet Nam
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2
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Mafa MS, Malgas S. Towards an understanding of the enzymatic degradation of complex plant mannan structures. World J Microbiol Biotechnol 2023; 39:302. [PMID: 37688610 PMCID: PMC10492685 DOI: 10.1007/s11274-023-03753-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 09/04/2023] [Indexed: 09/11/2023]
Abstract
Plant cell walls are composed of a heterogeneous mixture of polysaccharides that require several different enzymes to degrade. These enzymes are important for a variety of biotechnological processes, from biofuel production to food processing. Several classical mannanolytic enzyme functions of glycoside hydrolases (GH), such as β-mannanase, β-mannosidase and α-galactosidase activities, are helpful for efficient mannan hydrolysis. In this light, we bring three enzymes into the model of mannan degradation that have received little or no attention. By linking their three-dimensional structures and substrate specificities, we have predicted the interactions and cooperativity of these novel enzymes with classical mannanolytic enzymes for efficient mannan hydrolysis. The novel exo-β-1,4-mannobiohydrolases are indispensable for the production of mannobiose from the terminal ends of mannans, this product being the preferred product for short-chain mannooligosaccharides (MOS)-specific β-mannosidases. Second, the side-chain cleaving enzymes, acetyl mannan esterases (AcME), remove acetyl decorations on mannan that would have hindered backbone cleaving enzymes, while the backbone cleaving enzymes liberate MOS, which are preferred substrates of the debranching and sidechain cleaving enzymes. The nonhydrolytic expansins and swollenins disrupt the crystalline regions of the biomass, improving their accessibility for AcME and GH activities. Finally, lytic polysaccharide monooxygenases have also been implicated in promoting the degradation of lignocellulosic biomass or mannan degradation by classical mannanolytic enzymes, possibly by disrupting adsorbed mannan residues. Modelling effective enzymatic mannan degradation has implications for improving the saccharification of biomass for the synthesis of value-added and upcycling of lignocellulosic wastes.
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Affiliation(s)
- Mpho Stephen Mafa
- Carbohydrates and Enzymology Laboratory (CHEM-LAB), Department of Plant Sciences, University of the Free State, Bloemfontein, 9300 South Africa
| | - Samkelo Malgas
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Hatfield, 0028 South Africa
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3
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Zheng F, Basit A, Zhang Z, Zhuang H, Chen J, Zhang J. Improved production of recombinant β-mannanase (TaMan5) in Pichia pastoris and its synergistic degradation of lignocellulosic biomass. Front Bioeng Biotechnol 2023; 11:1244772. [PMID: 37744260 PMCID: PMC10513448 DOI: 10.3389/fbioe.2023.1244772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 08/22/2023] [Indexed: 09/26/2023] Open
Abstract
Mannan, a highly abundant and cost-effective natural resource, holds great potential for the generation of high-value compounds such as bioactive polysaccharides and biofuels. In this study, we successfully enhanced the expression of constructed GH5 β-mannanase (TaMan5) from Trichoderma asperellum ND-1 by employing propeptide in Pichia pastoris. By replacing the α-factor with propeptide (MGNRALNSMKFFKSQALALLAATSAVA), TaMan5 activity was significantly increased from 67.5 to 91.7 U/mL. It retained higher activity in the presence of 20% ethanol and 15% NaCl. When incubated with a high concentration of mannotriose or mannotetraose, the transglycosylation action of TaMan5 can be detected, yielding the corresponding production of mannotetraose or mannooligosaccharides. Moreover, the unique mechanism whereby TaMan5 catalyzes the degradation of mannan into mannobiose involves the transglycosylation of mannose to mannotriose or mannotetraose as a substrate to produce a mannotetraose or mannopentose intermediate, respectively. Additionally, the production of soluble sugars from lignocellulose is a crucial step in bioethanol development, and it is noteworthy that TaMan5 could synergistically yield fermentable sugars from corn stover and bagasse. These findings offered valuable insights and strategies for enhancing β-mannanase expression and efficient conversion of lignocellulosic biomass, providing cost-effective and sustainable approaches for high-value biomolecule and biofuel production.
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Affiliation(s)
- Fengzhen Zheng
- College of Biological and Environmental Engineering, Zhejiang Shuren University, Hangzhou, China
| | - Abdul Basit
- Department of Microbiology, University of Jhang, Jhang, Pakistan
| | - Zhiyue Zhang
- College of Biological and Environmental Engineering, Zhejiang Shuren University, Hangzhou, China
| | - Huan Zhuang
- Department of ENT and Head and Neck Surgery, The Children’s Hospital Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Jun Chen
- Interdisciplinary Research Academy, Zhejiang Shuren University, Hangzhou, China
| | - Jianfen Zhang
- College of Biological and Environmental Engineering, Zhejiang Shuren University, Hangzhou, China
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4
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Zheng B, Yang H, Xu X, Xiang Z, Hong Z, Zheng H, Wu A, Li H. Characterization of hemicellulose in Cunninghamia lanceolata stem during xylogenesis. Int J Biol Macromol 2023; 246:125530. [PMID: 37355061 DOI: 10.1016/j.ijbiomac.2023.125530] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 06/18/2023] [Accepted: 06/21/2023] [Indexed: 06/26/2023]
Abstract
In this study, hemicellulose was isolated from the apical, middle and basal segments of C. lanceolata stem to investigate the dynamic change of its structure during xylogenesis. Results showed that the C. lanceolata hemicellulose is mainly consisted of O-acetylgalactoglucomannan (GGM) which backbone is alternately linked by β-d-mannopyranosyl (Manp) and β-d-glucopyranosyl (Glcp) via (1 → 4)-glycosidic bond, while the side chains are α-d-galactopyranosyl (Galp) and acetyl. In addition, 4-O-methylglucuronoarabinoxylan (GAX) is another dominant structure of C. lanceolata hemicellulose which contains a linear backbone of (1 → 4)-β-d-xylopyranosyl (Xylp) and side chains of 4-O-Me-α-d-glucuronic acid (MeGlcpA) and α-L-arabinofuranose (Araf). The thickness of the cell wall, the ratio of GGM/GAX and the molecular weight of hemicellulose were increased as the extension of growth time. The degree of glycosyl substitutions of xylan and mannan was decreased from 10.34 % (apical) to 8.38 % (basal) and from 15.63 % (apical) to 10.49 % (basal), respectively. However, the total degree of acetylation was enhanced from 0.28 (apical) to 0.37 (basal). Transcriptome analysis showed that genes (CSLA9, IRX9H1, IRX10L, IRX15L, GMGT1, TBL19, TBL25, GUX2, GUX3, GXM1, F8H1 and F8H2) related to hemicellulose biosynthesis are mainly expressed in mature part. This study is of great significance for genetic breeding and high-value utilization of C. lanceolata.
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Affiliation(s)
- Biao Zheng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China; Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China
| | - Haoqiang Yang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China; Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China
| | - Xiaoli Xu
- Instrumental Analysis and Research Center, South China Agricultural University, Guangzhou 510642, China
| | - Zhouyang Xiang
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
| | - Zhou Hong
- Research institute of tropical Forestry, Chinese Academy of Forestry, Guangzhou 510520, China
| | - Huiquan Zheng
- Guangdong Provincial Key Laboratory of Silviculture, Protection and Utilization, Guangdong Academy of Forestry, Guangzhou 510520, China.
| | - Aimin Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China; Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China.
| | - Huiling Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, South China Agricultural University, Guangzhou 510642, China; Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China.
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Caputo F, Tõlgo M, Naidjonoka P, Krogh KBRM, Novy V, Olsson L. Investigating the role of AA9 LPMOs in enzymatic hydrolysis of differentially steam-pretreated spruce. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:68. [PMID: 37076886 PMCID: PMC10114483 DOI: 10.1186/s13068-023-02316-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 03/31/2023] [Indexed: 04/21/2023]
Abstract
BACKGROUND To realize the full potential of softwood-based forest biorefineries, the bottlenecks of enzymatic saccharification of softwood need to be better understood. Here, we investigated the potential of lytic polysaccharide monooxygenases (LPMO9s) in softwood saccharification. Norway spruce was steam-pretreated at three different severities, leading to varying hemicellulose retention, lignin condensation, and cellulose ultrastructure. Hydrolyzability of the three substrates was assessed after pretreatment and after an additional knife-milling step, comparing the efficiency of cellulolytic Celluclast + Novozym 188 and LPMO-containing Cellic CTec2 cocktails. The role of Thermoascus aurantiacus TaLPMO9 in saccharification was assessed through time-course analysis of sugar release and accumulation of oxidized sugars, as well as wide-angle X-ray scattering analysis of cellulose ultrastructural changes. RESULTS Glucose yield was 6% (w/w) with the mildest pretreatment (steam pretreatment at 210 °C without catalyst) and 66% (w/w) with the harshest (steam pretreatment at 210 °C with 3%(w/w) SO2) when using Celluclast + Novozym 188. Surprisingly, the yield was lower with all substrates when Cellic CTec2 was used. Therefore, the conditions for optimal LPMO activity were tested and it was found that enough O2 was present over the headspace and that the reducing power of the lignin of all three substrates was sufficient for the LPMOs in Cellic CTec2 to be active. Supplementation of Celluclast + Novozym 188 with TaLPMO9 increased the conversion of glucan by 1.6-fold and xylan by 1.5-fold, which was evident primarily in the later stages of saccharification (24-72 h). Improved glucan conversion could be explained by drastically reduced cellulose crystallinity of spruce substrates upon TaLPMO9 supplementation. CONCLUSION Our study demonstrated that LPMO addition to hydrolytic enzymes improves the release of glucose and xylose from steam-pretreated softwood substrates. Furthermore, softwood lignin provides enough reducing power for LPMOs, irrespective of pretreatment severity. These results provided new insights into the potential role of LPMOs in saccharification of industrially relevant softwood substrates.
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Affiliation(s)
- Fabio Caputo
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden
| | - Monika Tõlgo
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, Kemigården 4, 412 96, Gothenburg, Sweden
| | - Polina Naidjonoka
- Wallenberg Wood Science Center, Chalmers University of Technology, Kemigården 4, 412 96, Gothenburg, Sweden
- Division of Materials Physics, Department of Physics, Chalmers University of Technology, Kemigården 1, 412 96, Gothenburg, Sweden
| | | | - Vera Novy
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, Kemigården 4, 412 96, Gothenburg, Sweden
| | - Lisbeth Olsson
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 412 96, Gothenburg, Sweden.
- Wallenberg Wood Science Center, Chalmers University of Technology, Kemigården 4, 412 96, Gothenburg, Sweden.
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Østby H, Várnai A. Hemicellulolytic enzymes in lignocellulose processing. Essays Biochem 2023; 67:533-550. [PMID: 37068264 PMCID: PMC10160854 DOI: 10.1042/ebc20220154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/25/2023] [Accepted: 01/30/2023] [Indexed: 04/19/2023]
Abstract
Lignocellulosic biomass is the most abundant source of carbon-based material on a global basis, serving as a raw material for cellulosic fibers, hemicellulosic polymers, platform sugars, and lignin resins or monomers. In nature, the various components of lignocellulose (primarily cellulose, hemicellulose, and lignin) are decomposed by saprophytic fungi and bacteria utilizing specialized enzymes. Enzymes are specific catalysts and can, in many cases, be produced on-site at lignocellulose biorefineries. In addition to reducing the use of often less environmentally friendly chemical processes, the application of such enzymes in lignocellulose processing to obtain a range of specialty products can maximize the use of the feedstock and valorize many of the traditionally underutilized components of lignocellulose, while increasing the economic viability of the biorefinery. While cellulose has a rich history of use in the pulp and paper industries, the hemicellulosic fraction of lignocellulose remains relatively underutilized in modern biorefineries, among other reasons due to the heterogeneous chemical structure of hemicellulose polysaccharides, the composition of which varies significantly according to the feedstock and the choice of pretreatment method and extraction solvent. This paper reviews the potential of hemicellulose in lignocellulose processing with focus on what can be achieved using enzymatic means. In particular, we discuss the various enzyme activities required for complete depolymerization of the primary hemicellulose types found in plant cell walls and for the upgrading of hemicellulosic polymers, oligosaccharides, and pentose sugars derived from hemicellulose depolymerization into a broad spectrum of value-added products.
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Affiliation(s)
- Heidi Østby
- Norwegian University of Life Sciences (NMBU), Faculty of Chemistry, Biotechnology and Food Science, P.O. Box 5003, N-1432 Aas, Norway
| | - Anikó Várnai
- Norwegian University of Life Sciences (NMBU), Faculty of Chemistry, Biotechnology and Food Science, P.O. Box 5003, N-1432 Aas, Norway
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7
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Tõlgo M, Hegnar OA, Larsbrink J, Vilaplana F, Eijsink VGH, Olsson L. Enzymatic debranching is a key determinant of the xylan-degrading activity of family AA9 lytic polysaccharide monooxygenases. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:2. [PMID: 36604763 PMCID: PMC9814446 DOI: 10.1186/s13068-022-02255-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 12/26/2022] [Indexed: 01/07/2023]
Abstract
BACKGROUND Previous studies have revealed that some Auxiliary Activity family 9 (AA9) lytic polysaccharide monooxygenases (LPMOs) oxidize and degrade certain types of xylans when incubated with mixtures of xylan and cellulose. Here, we demonstrate that the xylanolytic activities of two xylan-active LPMOs, TtLPMO9E and TtLPMO9G from Thermothielavioides terrestris, strongly depend on the presence of xylan substitutions. RESULTS Using mixtures of phosphoric acid-swollen cellulose (PASC) and wheat arabinoxylan (WAX), we show that removal of arabinosyl substitutions with a GH62 arabinofuranosidase resulted in better adsorption of xylan to cellulose, and enabled LPMO-catalyzed cleavage of this xylan. Furthermore, experiments with mixtures of PASC and arabinoglucuronoxylan from spruce showed that debranching of xylan with the GH62 arabinofuranosidase and a GH115 glucuronidase promoted LPMO activity. Analyses of mixtures with PASC and (non-arabinosylated) beechwood glucuronoxylan showed that GH115 action promoted LPMO activity also on this xylan. Remarkably, when WAX was incubated with Avicel instead of PASC in the presence of the GH62, both xylan and cellulose degradation by the LPMO9 were impaired, showing that the formation of cellulose-xylan complexes and their susceptibility to LPMO action also depend on the properties of the cellulose. These debranching effects not only relate to modulation of the cellulose-xylan interaction, which influences the conformation and rigidity of the xylan, but likely also affect the LPMO-xylan interaction, because debranching changes the architecture of the xylan surface. CONCLUSIONS Our results shed new light on xylanolytic LPMO9 activity and on the functional interplay and possible synergies between the members of complex lignocellulolytic enzyme cocktails. These findings will be relevant for the development of future lignocellulolytic cocktails and biomaterials.
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Affiliation(s)
- Monika Tõlgo
- grid.5371.00000 0001 0775 6028Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden ,grid.5371.00000 0001 0775 6028Wallenberg Wood Science Centre, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Olav A. Hegnar
- grid.19477.3c0000 0004 0607 975XFaculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, 1433 Ås, Norway
| | - Johan Larsbrink
- grid.5371.00000 0001 0775 6028Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden ,grid.5371.00000 0001 0775 6028Wallenberg Wood Science Centre, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Francisco Vilaplana
- grid.5037.10000000121581746Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, 106 91 Stockholm, Sweden ,grid.5037.10000000121581746Wallenberg Wood Science Centre, KTH Royal Institute of Technology, 100 44 Stockholm, Sweden
| | - Vincent G. H. Eijsink
- grid.19477.3c0000 0004 0607 975XFaculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, 1433 Ås, Norway
| | - Lisbeth Olsson
- grid.5371.00000 0001 0775 6028Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden ,grid.5371.00000 0001 0775 6028Wallenberg Wood Science Centre, Chalmers University of Technology, 412 96 Gothenburg, Sweden
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Kellock M, Rahikainen J, Borisova AS, Voutilainen S, Koivula A, Kruus K, Marjamaa K. Inhibitory effect of lignin on the hydrolysis of xylan by thermophilic and thermolabile GH11 xylanases. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:49. [PMID: 35568899 PMCID: PMC9107766 DOI: 10.1186/s13068-022-02148-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 04/30/2022] [Indexed: 11/10/2022]
Abstract
Abstract
Background
Enzymatic hydrolysis of lignocellulosic biomass into platform sugars can be enhanced by the addition of accessory enzymes, such as xylanases. Lignin from steam pretreated biomasses is known to inhibit enzymes by non-productively binding enzymes and limiting access to cellulose. The effect of enzymatically isolated lignin on the hydrolysis of xylan by four glycoside hydrolase (GH) family 11 xylanases was studied. Two xylanases from the mesophilic Trichoderma reesei, TrXyn1, TrXyn2, and two forms of a thermostable metagenomic xylanase Xyl40 were compared.
Results
Lignin isolated from steam pretreated spruce decreased the hydrolysis yields of xylan for all the xylanases at 40 and 50 °C. At elevated hydrolysis temperature of 50 °C, the least thermostable xylanase TrXyn1 was most inhibited by lignin and the most thermostable xylanase, the catalytic domain (CD) of Xyl40, was least inhibited by lignin. Enzyme activity and binding to lignin were studied after incubation of the xylanases with lignin for up to 24 h at 40 °C. All the studied xylanases bound to lignin, but the thermostable xylanases retained 22–39% of activity on the lignin surface for 24 h, whereas the mesophilic T. reesei xylanases become inactive. Removing of N-glycans from the catalytic domain of Xyl40 increased lignin inhibition in hydrolysis of xylan when compared to the glycosylated form. By comparing the 3D structures of these xylanases, features contributing to the increased thermal stability of Xyl40 were identified.
Conclusions
High thermal stability of xylanases Xyl40 and Xyl40-CD enabled the enzymes to remain partially active on the lignin surface. N-glycosylation of the catalytic domain of Xyl40 increased the lignin tolerance of the enzyme. Thermostability of Xyl40 was most likely contributed by a disulphide bond and salt bridge in the N-terminal and α-helix regions.
Graphical Abstract
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9
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Gladkov GV, Kimeklis AK, Afonin AM, Lisina TO, Orlova OV, Aksenova TS, Kichko AA, Pinaev AG, Andronov EE. The Structure of Stable Cellulolytic Consortia Isolated from Natural Lignocellulosic Substrates. Int J Mol Sci 2022; 23:ijms231810779. [PMID: 36142684 PMCID: PMC9501375 DOI: 10.3390/ijms231810779] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 08/31/2022] [Accepted: 09/04/2022] [Indexed: 10/27/2022] Open
Abstract
Recycling plant matter is one of the challenges facing humanity today and depends on efficient lignocellulose degradation. Although many bacterial strains from natural substrates demonstrate cellulolytic activities, the CAZymes (Carbohydrate-Active enZYmes) responsible for these activities are very diverse and usually distributed among different bacteria in one habitat. Thus, using microbial consortia can be a solution to rapid and effective decomposition of plant biomass. Four cellulolytic consortia were isolated from enrichment cultures from composting natural lignocellulosic substrates—oat straw, pine sawdust, and birch leaf litter. Enrichment cultures facilitated growth of similar, but not identical cellulose-decomposing bacteria from different substrates. Major components in all consortia were from Proteobacteria, Actinobacteriota and Bacteroidota, but some were specific for different substrates—Verrucomicrobiota and Myxococcota from straw, Planctomycetota from sawdust and Firmicutes from leaf litter. While most members of the consortia were involved in the lignocellulose degradation, some demonstrated additional metabolic activities. Consortia did not differ in the composition of CAZymes genes, but rather in axillary functions, such as ABC-transporters and two-component systems, usually taxon-specific and associated with CAZymes. Our findings show that enrichment cultures can provide reproducible cellulolytic consortia from various lignocellulosic substrates, the stability of which is ensured by tight microbial relations between its components.
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Affiliation(s)
- Grigory V. Gladkov
- All-Russian Research Institute of Agricultural Microbiology, 196608 Saint Petersburg, Russia
- Correspondence: ; Tel.: +7-921-402-65-16
| | - Anastasiia K. Kimeklis
- All-Russian Research Institute of Agricultural Microbiology, 196608 Saint Petersburg, Russia
- Department of Applied Ecology, Saint-Petersburg State University, 199034 Saint Petersburg, Russia
| | - Alexey M. Afonin
- All-Russian Research Institute of Agricultural Microbiology, 196608 Saint Petersburg, Russia
| | - Tatiana O. Lisina
- All-Russian Research Institute of Agricultural Microbiology, 196608 Saint Petersburg, Russia
| | - Olga V. Orlova
- All-Russian Research Institute of Agricultural Microbiology, 196608 Saint Petersburg, Russia
| | - Tatiana S. Aksenova
- All-Russian Research Institute of Agricultural Microbiology, 196608 Saint Petersburg, Russia
| | - Arina A. Kichko
- All-Russian Research Institute of Agricultural Microbiology, 196608 Saint Petersburg, Russia
| | - Alexander G. Pinaev
- All-Russian Research Institute of Agricultural Microbiology, 196608 Saint Petersburg, Russia
| | - Evgeny E. Andronov
- All-Russian Research Institute of Agricultural Microbiology, 196608 Saint Petersburg, Russia
- Dokuchaev Soil Science Institute, 119017 Moscow, Russia
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Younes A, Li M, Karboune S. Cocoa bean shells: a review into the chemical profile, the bioactivity and the biotransformation to enhance their potential applications in foods. Crit Rev Food Sci Nutr 2022; 63:9111-9135. [PMID: 35467453 DOI: 10.1080/10408398.2022.2065659] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
During processing, cocoa bean shells (CBS) are de-hulled from the bean and discarded as waste. Undermined by its chemical and bioactive composition, CBS is abundant in dietary fiber and phenolic compounds that may serve the valorization purpose of this by-product material into prebiotic and functional ingredients. In addition, the cell-wall components of CBS can be combined through enzymatic feruloylation to obtain feruloylated oligo- and polysaccharides (FOs), further enhancing the techno-functional properties. FOs have attracted scientific attention due to their prebiotic, antimicrobial, anti-inflammatory and antioxidant functions inherent to their structural features. This review covers the chemical and bioactive compositions of CBS as well as their modifications upon cocoa processing. Physical, chemical, and enzymatic approaches to extract and bio-transform bioactive components from the cell wall matrix of CBS were also discussed. Although nonspecific to CBS, studies were compiled to investigate efforts done to extract and produce feruloylated oligo- and polysaccharides from the cell wall materials.
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Affiliation(s)
- Amalie Younes
- Department of Food Science and Agricultural Chemistry, Macdonald Campus, McGill University, Montreal, Québec, Canada
| | - Mingqin Li
- Department of Food Science and Agricultural Chemistry, Macdonald Campus, McGill University, Montreal, Québec, Canada
| | - Salwa Karboune
- Department of Food Science and Agricultural Chemistry, Macdonald Campus, McGill University, Montreal, Québec, Canada
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Sagarika MS, Parameswaran C, Senapati A, Barala J, Mitra D, Prabhukarthikeyan SR, Kumar A, Nayak AK, Panneerselvam P. Lytic polysaccharide monooxygenases (LPMOs) producing microbes: A novel approach for rapid recycling of agricultural wastes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150451. [PMID: 34607097 DOI: 10.1016/j.scitotenv.2021.150451] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 09/12/2021] [Accepted: 09/15/2021] [Indexed: 06/13/2023]
Abstract
Out of the huge quantity of agricultural wastes produced globally, rice straw is one of the most abundant ligno-cellulosic waste. For efficient utilization of these wastes, several cost-effective biological processes are available. The practice of field level in-situ or ex-situ decomposition of rice straw is having less degree of adoption due to its poor decomposition ability within a short time span between rice harvest and sowing of the next crop. Agricultural wastes including rice straw are in general utilized by using lignocellulose degrading microbes for industrial metabolite or compost production. However, bioconversion of crystalline cellulose and lignin present in the waste, into simple molecules is a challenging task. To resolve this issue, researchers have identified a novel new generation microbial enzyme i.e., lytic polysaccharide monooxygenases (LPMOs) and reported that the combination of LPMOs with other glycolytic enzymes are found efficient. This review explains the progress made in LPMOs and their role in lignocellulose bioconversion and the possibility of exploring LPMOs producers for rapid decomposition of agricultural wastes. Also, it provides insights to identify the knowledge gaps in improving the potential of the existing ligno-cellulolytic microbial consortium for efficient utilization of agricultural wastes at industrial and field levels.
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Affiliation(s)
- Mahapatra Smruthi Sagarika
- ICAR - National Rice Research Institute, Cuttack, Odisha 753006, India; Indira Gandhi Agricultural University, Raipur, Chhattisgarh 492012, India
| | | | - Ansuman Senapati
- ICAR - National Rice Research Institute, Cuttack, Odisha 753006, India
| | - Jatiprasad Barala
- ICAR - National Rice Research Institute, Cuttack, Odisha 753006, India
| | - Debasis Mitra
- ICAR - National Rice Research Institute, Cuttack, Odisha 753006, India
| | | | - Anjani Kumar
- ICAR - National Rice Research Institute, Cuttack, Odisha 753006, India
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Lee DS, Song Y, Lee YG, Bae HJ. Comparative Evaluation of Adsorption of Major Enzymes in a Cellulase Cocktail Obtained from Trichoderma reesei onto Different Types of Lignin. Polymers (Basel) 2022; 14:polym14010167. [PMID: 35012188 PMCID: PMC8747337 DOI: 10.3390/polym14010167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/22/2021] [Accepted: 12/29/2021] [Indexed: 02/04/2023] Open
Abstract
Cellulase adsorption onto lignin decreases the productivity of enzymatic hydrolysis of lignocellulosic biomass. Here, adsorption of enzymes onto different types of lignin was investigated, and the five major enzymes—cellobiohydrolases (CBHs), endoglucanase (Cel7B), β-glucosidase (Cel3A), xylanase (XYNIV), and mannanase (Man5A)—in a cellulase cocktail obtained from Trichoderma reesei were individually analyzed through SDS-PAGE and zymogram assay. Lignin was isolated from woody (oak and pine lignin) and herbaceous (rice straw and kenaf lignin) plants. The relative adsorption of CBHs compared to the control was in the range of 14.15–18.61%. The carbohydrate binding motif (CBM) of the CBHs contributed to higher adsorption levels in oak and kenaf lignin, compared to those in pine and rice lignin. The adsorption of endoglucanase (Cel7B) by herbaceous plant lignin was two times higher than that of woody lignin, whereas XYNIV showed the opposite pattern. β-glucosidase (Cel3A) displayed the highest and lowest adsorption ratios on rice straw and kenaf lignin, respectively. Mannanase (Man5A) was found to have the lowest adsorption ratio on pine lignin. Our results showed that the hydrophobic properties of CBM and the enzyme structures are key factors in adsorption onto lignin, whereas the properties of specific lignin types indirectly affect adsorption.
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Affiliation(s)
- Dae-Seok Lee
- Bio-Energy Research Center, Chonnam National University, Gwangju 500-575, Korea; (D.-S.L.); (Y.S.)
| | - Younho Song
- Bio-Energy Research Center, Chonnam National University, Gwangju 500-575, Korea; (D.-S.L.); (Y.S.)
| | - Yoon-Gyo Lee
- Department of Wood Science and Landscape Architecture, Chonnam National University, Gwangju 500-757, Korea;
| | - Hyeun-Jong Bae
- Bio-Energy Research Center, Chonnam National University, Gwangju 500-575, Korea; (D.-S.L.); (Y.S.)
- Department of Bioenergy Science and Technology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju 500-757, Korea
- Correspondence: ; Tel.: +81-62-530-2097
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Galic M, Cilerdzic J, Stajic M. Degradation of pretreated agroforestry residues by selected micromycetes. ZBORNIK MATICE SRPSKE ZA PRIRODNE NAUKE 2022. [DOI: 10.2298/zmspn2243089g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Nowadays, there are huge amounts of lignocellulosic materials left in
agroforestry practice, which can be transformed into useful products.
Biomass exploitation could be aiming not only at replacing conventional
energy sources but also at preserving biodiversity and natural ecosystems.
Five micromycetes were studied with goal to determine their potential to
produce active cellulases as well as the ability to decompose pretreated
wheat straw and oak sawdust after seven days of solid-state fermentation.
Wheat straw was better lignocellulosic substrate than oak sawdust for the
production of cellulases in all five micromycetes. Thus, Penicillium solitum
BEOFB 1190m has shown to be the best producer of highly active forms of
xylanases (7532.36 ? 89.37 U/L). The most active endo- and exocellulases
(2299.70 ? 72.17 U/L and 195.66 ? 4.64 U/L, respectively) were produced by
Trichoderma harzianum BEOFB 1230m, while the maximal value of ?-glucosidase
activity (215.69 ? 3.13 U/L) was detected after Fusarium graminearum BEOFB
820m cultivation. T. harzianum also showed high efficiency in wheat straw
cellulose and hemicellulose depolymerization (23.90% and 33.00%,
respectively), which resulted in the highest dry matter loss (36.25%). The
results of the study showed great potential of tested micromycetes to
synthesize cellulolytic enzymes and consequently transform abundant,
low-cost plant residues such as wheat straw into useful products including
biofuel.
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Affiliation(s)
- Milica Galic
- University of Belgrade, Faculty of Biology, Belgrade, Serbia
| | | | - Mirjana Stajic
- University of Belgrade, Faculty of Biology, Belgrade, Serbia
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Lan Q, Duan Y, Wu P, Li X, Yu Y, Shi B, Zhou J, Lu H. Coordinately express hemicellulolytic enzymes in Kluyveromyces marxianus to improve the saccharification and ethanol production from corncobs. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:220. [PMID: 34809677 PMCID: PMC8607645 DOI: 10.1186/s13068-021-02070-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 11/10/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Hemicellulose acts as one factor contributing to the recalcitrance of lignocellulose that prevents cellulases to degrade the cellulose efficiently even in low quantities. Supplement of hemicellulases can enhance the performance of commercial cellulases in the enzymatic hydrolyses of lignocellulose. Kluyveromyce marxianus is an attractive yeast for cellulosic ethanol fermentation, as well as a promising host for heterologous protein production, since it has remarkable thermotolerance, high growth rate, and broad substrate spectrum etc. In this study, we attempted to coordinately express multiple hemicellulases in K. marxianus through a 2A-mediated ribosome skipping to self-cleave polyproteins, and investigated their capabilities for saccharification and ethanol production from corncobs. RESULTS Two polycistronic genes IMPX and IMPαX were constructed to test the self-cleavage of P2A sequence from the Foot-and-Mouth Disease virus (FMDV) in K. marxianus. The IMPX gene consisted of a β-mannanase gene M330 (without the stop codon), a P2A sequence and a β-xylanase gene Xyn-CDBFV in turn. In the IMPαX gene, there was an additional α-factor signal sequence in frame with the N-terminus of Xyn-CDBFV. The extracellular β-mannanase activities of the IMPX and IMPαX strains were 21.34 and 15.50 U/mL, respectively, but the extracellular β-xylanase activity of IMPαX strain was much higher than that of the IMPX strain, which was 136.17 and 42.07 U/mL, respectively. Subsequently, two recombinant strains, the IXPαR and IMPαXPαR, were constructed to coordinately and secretorily express two xylantic enzymes, Xyn-CDBFV and β-D-xylosidase RuXyn1, or three hemicellulolytic enzymes including M330, Xyn-CDBFV and RuXyn1. In fed-batch fermentation, extracellular activities of β-xylanase and β-xylosidase in the IXPαR strain were 1664.2 and 0.90 U/mL. Similarly, the IMPαXPαR strain secreted the three enzymes, β-mannanase, β-xylanase, and β-xylosidase, with the activities of 159.8, 2210.5, and 1.25 U/mL, respectively. Hemicellulolases of both strains enhanced the yields of glucose and xylose from diluted acid pretreated (DAP) corncobs when acted synergistically with commercial cellulases. In hybrid saccharification and fermentation (HSF) of DAP corncobs, hemicellulases of the IMPαXPαR strain increased the ethanol yield by 8.7% at 144 h compared with the control. However, both ethanol and xylose yields were increased by 12.7 and 18.2%, respectively, at 120 h in HSF of aqueous ammonia pretreated (AAP) corncobs with this strain. Our results indicated that coordinate expression of hemicellulolytic enzymes in K. marxianus promoted the saccharification and ethanol production from corncobs. CONCLUSIONS The FMDV P2A sequence showed high efficiency in self-cleavage of polyproteins in K. marxianus and could be used for secretory expression of multiple enzymes in the presence of their signal sequences. The IMPαXPαR strain coexpressed three hemicellulolytic enzymes improved the saccharification and ethanol production from corncobs, and could be used as a promising strain for ethanol production from lignocelluloses.
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Affiliation(s)
- Qing Lan
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
| | - Yitong Duan
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
| | - Pingping Wu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
| | - Xueyin Li
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
| | - Yao Yu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China
| | - Bo Shi
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, 12 Zhongguancun South Street, Beijing, 100081, People's Republic of China
| | - Jungang Zhou
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China.
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China.
| | - Hong Lu
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China.
- Shanghai Engineering Research Center of Industrial Microorganisms, Fudan University, 2005 Songhu Road, Shanghai, 200438, People's Republic of China.
- Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, People's Republic of China.
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Sun D, Zhang J, Li C, Wang TF, Qin HM. Biochemical and structural characterization of a novel thermophilic and acidophilic β-mannanase from Aspergillus calidoustus. Enzyme Microb Technol 2021; 150:109891. [PMID: 34489044 DOI: 10.1016/j.enzmictec.2021.109891] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 07/31/2021] [Accepted: 08/02/2021] [Indexed: 01/09/2023]
Abstract
β-Mannanases hydrolyze lignocellulosic biomass with the release of mannan oligosaccharides, which are considered as renewable resource in higher plants. Here, we cloned, expressed and characterized a novel endo-β-mannanase (ManAC) from Aspergillus calidoustus. Homology alignment analysis indicated that ManAC belonged to glycosyl hydrolase (GH) 5 family members. The analysis of structural homologous model revealed that five residues, Arg116, Asn231, His305, Tyr307, and Trp370, constituted the active site of ManAC. Glu232 and Glu340, proton donor and nucleophile, formed the catalytic residues of ManAC. The recombinant ManAC exhibited maximal activity at pH 2.5 and 70 °C, and it was acid tolerant at a pH range of 2.0-6.0 and thermostable under 60 °C. Meanwhile, the activity of ManAC was not significantly affected by various metal ions, except for Mg2+ and Ag2+. The recombinant ManAC exhibited the highest β-mannanase activity towards locust bean gum (669.7 U/mg) with the Km and Vmax values of 3.4 mg/mL and 982.4 μmol/min/mg, respectively. These thermophilic and acidophilicc characteristics is better than most extreme β-mannanase. As the first reported mannanse from Aspergillus calidoustus (ManAC), these excellent properties of ManAC strongly promote the synthesis of mannooligosaccharides which have potential for food and feed industrial applications.
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Affiliation(s)
- Dengyue Sun
- State Key Laboratory of Biobased Material and Green Papermaking, College of Bioengineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan, 250100, PR China
| | - Jie Zhang
- State Key Laboratory of Biobased Material and Green Papermaking, College of Bioengineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan, 250100, PR China
| | - Chao Li
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, PR China
| | - Teng-Fei Wang
- State Key Laboratory of Biobased Material and Green Papermaking, College of Bioengineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan, 250100, PR China.
| | - Hui-Min Qin
- State Key Laboratory of Biobased Material and Green Papermaking, College of Bioengineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan, 250100, PR China; College of Biotechnology, Tianjin University of Science and Technology, Tianjin, 300457, PR China.
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A Thermophilic GH5 Endoglucanase from Aspergillus fumigatus and Its Synergistic Hydrolysis of Mannan-Containing Polysaccharides. Catalysts 2021. [DOI: 10.3390/catal11070862] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In this study, we isolated and identified a thermophilic strain of Aspergillus fumigatus from the “Daqu” samples. Transcriptomic analysis of A. fumigatus identified 239 carbohydrate-active enzymes (CAZy)-encoding genes, including 167 glycoside hydrolase (GH)-encoding genes, 58 glycosyltransferase (GT)-encoding genes, 2 polysaccharide lyase (PLs)-encoding genes and 12 carbohydrate esterase (CEs)-encoding genes, which indicates that the strain has a strong potential for application for enzyme production. Furthermore, we also identified a novel endoglucanase gene (AfCel5A), which was expressed in Pichia pastoris and characterized. The novel endoglucanase AfCel5A exhibited the highest hydrolytic activity against CMC-Na and the optimal activity at 80 °C and pH 4.0 and also showed good stability at pH 3.0–11.0 and below 70 °C. The Km and Vmax values of AfCel5 were 0.16 ± 0.05 mg·mL−1 and 7.23 ± 0.33 mol mg−1·min−1, respectively, using CMC-Na as a substrate. Further, the endoglucanase exhibited a high tolerance toward NaCl as well as glucose. In addition, the finding that the endoglucanase AfCel5A in combination with β-mannanse (ManBK) clearly increased the release of total reducing sugars of glucomannan by up to 74% is significant.
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17
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Lignocellulolytic bacteria isolated from organic rice field soils for enzyme production using agricultural wastes: Screening, medium optimization, and co-culture. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2021. [DOI: 10.1016/j.bcab.2021.101988] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Lee DS, Lee YG, Cho EJ, Song Y, Bae HJ. Hydrolysis pattern analysis of xylem tissues of woody plants pretreated with hydrogen peroxide and acetic acid: rapid saccharification of softwood for economical bioconversion. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:37. [PMID: 33549141 PMCID: PMC7866737 DOI: 10.1186/s13068-021-01889-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 01/25/2021] [Indexed: 05/20/2023]
Abstract
BACKGROUND Woody plants with high glucose content are alternative bioresources for the production of biofuels and biochemicals. Various pretreatment methods may be used to reduce the effects of retardation factors such as lignin interference and cellulose structural recalcitrance on the degradation of the lignocellulose material of woody plants. RESULTS A hydrogen peroxide-acetic acid (HPAC) pretreatment was used to reduce the lignin content of several types of woody plants, and the effect of the cellulose structural recalcitrance on the enzymatic hydrolysis was analyzed. The cellulose structural recalcitrance and the degradation patterns of the wood fibers in the xylem tissues of Quercus acutissima (hardwood) resulted in greater retardation in the enzymatic saccharification than those in the tracheids of Pinus densiflora (softwood). In addition to the HPAC pretreatment, the application of supplementary enzymes (7.5 FPU cellulase for 24 h) further increased the hydrolysis rate of P. densiflora from 61.42 to 91.94% whereas the same effect was not observed for Q. acutissima. It was also observed that endoxylanase synergism significantly affected the hydrolysis of P. densiflora. However, this synergistic effect was lower for other supplementary enzymes. The maximum concentration of the reducing sugars produced from 10% softwood was 89.17 g L-1 after 36 h of hydrolysis with 15 FPU cellulase and other supplementary enzymes. Approximately 80 mg mL-1 of reducing sugars was produced with the addition of 7.5 FPU cellulase and other supplementary enzymes after 36 h, achieving rapid saccharification. CONCLUSION HPAC pretreatment removed the interference of lignin, reduced structural recalcitrance of cellulose in the P. densiflora, and enabled rapid saccharification of the woody plants including a high concentration of insoluble substrates with only low amounts of cellulase. HPAC pretreatment may be a viable alternative for the cost-efficient production of biofuels or biochemicals from softwood plant tissues.
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Affiliation(s)
- Dae-Seok Lee
- Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Yoon-Gyo Lee
- Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Eun Jin Cho
- Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Younho Song
- Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757, Republic of Korea
| | - Hyeun-Jong Bae
- Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757, Republic of Korea.
- Department of Bioenergy Science and Technology, College of Agriculture and Life Sciences, Chonnam National University, Gwangju, 500-757, Republic of Korea.
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Ouyang S, Shi J, Qiao H, Zheng Z, Ouyang J, Lai C. The key role of delignification in overcoming the inherent recalcitrance of Chinese fir for biorefining. BIORESOURCE TECHNOLOGY 2021; 319:124154. [PMID: 33011629 DOI: 10.1016/j.biortech.2020.124154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/14/2020] [Accepted: 09/17/2020] [Indexed: 06/11/2023]
Abstract
The enzymatic digestibility of softwood is hindered for its highly recalcitrant nature to enzymatic attack. In this study, the effects of dilute sulfuric acid pretreatment (DSAP), acidic sodium chlorite pretreatment (SCP), and their combined pretreatments (DSA-SCP and SC-DSAP) on Chinese fir sawdust were investigated, respectively. Results demonstrated that lignin was the most important obstacle, and digestibility increased linearly with lignin removal yield. Furthermore, the results revealed that the order of sequential pretreatment significantly affected the delignification, and hemicellulose should be removed first. Compared to SC-DSAP, DSA-SCP involving the hemicellulose-removal-first strategy exhibited higher delignification efficiency. DSA-SCP caused lignin removal of 92.3% and the enzymatic hydrolysis was high of 97.9%. Finally, a regression model with high reliability was established to quickly evaluate pretreatment process. In summary, this study highlighted the importance of delignification for saccharification of softwood and unveiled the effect of hemicellulose on delignification.
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Affiliation(s)
- Shuiping Ouyang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Jinjie Shi
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Hui Qiao
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Zhaojuan Zheng
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Jia Ouyang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China.
| | - Chenhuan Lai
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
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20
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Chettri D, Verma AK, Verma AK. Innovations in CAZyme gene diversity and its modification for biorefinery applications. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2020; 28:e00525. [PMID: 32963975 PMCID: PMC7490808 DOI: 10.1016/j.btre.2020.e00525] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/04/2020] [Accepted: 08/30/2020] [Indexed: 02/07/2023]
Abstract
For sustainable growth, concept of biorefineries as recourse to the "fossil derived" energy source is important. Here, the Carbohydrate Active enZymes (CAZymes) play decisive role in generation of biofuels and related sugar-based products utilizing lignocellulose as a carbon source. Given their industrial significance, extensive studies on the evolution of CAZymes have been carried out. Various bacterial and fungal organisms have been scrutinized for the development of CAZymes, where advance techniques for strain enhancement such as CRISPR and analysis of specific expression systems have been deployed. Specific Omic-based techniques along with protein engineering have been adopted to unearth novel CAZymes and improve applicability of existing enzymes. In-Silico computational research and functional annotation of new CAZymes to synergy experiments are being carried out to devise cocktails of enzymes for use in biorefineries. Thus, with the establishment of these technologies, increased diversity of CAZymes with broad span of functions and applications is seen.
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21
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Combination of CTec2 and GH5 or GH26 Endo-Mannanases for Effective Lignocellulosic Biomass Degradation. Catalysts 2020. [DOI: 10.3390/catal10101193] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Among endo-mannanases, glycoside hydrolase (GH) family 26 enzymes have been shown to be more catalytically active than GH5 enzymes on mannans. However, only GH5 endo-mannanases have been used for the formulation of enzyme cocktails. In this study, Bacillus sp.-derived GH5 and GH26 endo-mannanases were comparatively analysed biochemically for their synergistic action with a commercial cellulase blend, CTec2, during pre-treated lignocellulose degradation. Substrate specificity and thermo-stability studies on mannan substrates showed that GH26 endo-mannanase was more catalytically active and stable than GH5. GH26 also exhibited higher binding affinity for mannan than GH5, while GH5 showed more affinity for lignocellulosic substrates than GH26. Applying the endo-mannanases in combination with CTec2 for lignocellulose degradation led to synergism with a 1.3-fold increase in reducing sugar release compared to when CTec2 was used alone. This study showed that using the activity of endo-mannanases displayed with model substrates is a poor predictor of their activity and synergism on complex lignocelluloses.
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22
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Østby H, Hansen LD, Horn SJ, Eijsink VGH, Várnai A. Enzymatic processing of lignocellulosic biomass: principles, recent advances and perspectives. J Ind Microbiol Biotechnol 2020; 47:623-657. [PMID: 32840713 PMCID: PMC7658087 DOI: 10.1007/s10295-020-02301-8] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 07/30/2020] [Indexed: 02/06/2023]
Abstract
Efficient saccharification of lignocellulosic biomass requires concerted development of a pretreatment method, an enzyme cocktail and an enzymatic process, all of which are adapted to the feedstock. Recent years have shown great progress in most aspects of the overall process. In particular, increased insights into the contributions of a wide variety of cellulolytic and hemicellulolytic enzymes have improved the enzymatic processing step and brought down costs. Here, we review major pretreatment technologies and different enzyme process setups and present an in-depth discussion of the various enzyme types that are currently in use. We pay ample attention to the role of the recently discovered lytic polysaccharide monooxygenases (LPMOs), which have led to renewed interest in the role of redox enzyme systems in lignocellulose processing. Better understanding of the interplay between the various enzyme types, as they may occur in a commercial enzyme cocktail, is likely key to further process improvements.
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Affiliation(s)
- Heidi Østby
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Line Degn Hansen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Svein J Horn
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway
| | - Anikó Várnai
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, 1432, Aas, Norway.
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Jiang S, Zheng X, Li L. De novo assembly of Auricularia polytricha transcriptome and discovery of genes involved in the degradation of lignocellulose. Biotechnol Appl Biochem 2020; 68:983-991. [PMID: 32786100 DOI: 10.1002/bab.2005] [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: 03/15/2020] [Accepted: 07/27/2020] [Indexed: 11/10/2022]
Abstract
Auricularia polytricha belonging to Basidiomycota has the ability to degrade lignocellulose. However, there has been no resource in public databases examining the transcriptome of A. polytricha. In this study, high-throughput sequencing platform BGISEQ-500 was used to generate large amount of transcript sequences from A. polytricha for gene discovery and molecular marker development. A total of 28,102 unigenes were discovered from the assembly of clean reads. In addition, functional categorization of the gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) metabolic pathways revealed several important biological processes. GO annotation analysis presented 47 categories, with the major subcategories being catalytic activity, binding, cellular process, metabolic process, and cell. Among the five functional categories and 21 subcategories of processes discovered from KEGG, global and overview maps, carbohydrate metabolism, transport, and catabolism are the main subcategories. Furthermore, among the unigenes related to lignocellulosic degradation discovered by KEGG pathway enrichment analysis, 2, 5, and 16 unigenes in de novo assembly of A. polytricha transcriptome were found to relate to cellulose, hemicellulose, and lignin degradation, respectively. The study provided valuable information on the degradation of lignocellulose to facilitate research on the degradation mechanism, molecular marker, functional research, gene mapping, and other multigenomic studies of species containing lignocellulose.
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Affiliation(s)
- Shiyu Jiang
- College of Grain and Food science, Henan University of Technology, Zhengzhou, Henan, People's Republic of China
| | - Xueling Zheng
- College of Grain and Food science, Henan University of Technology, Zhengzhou, Henan, People's Republic of China
| | - Li Li
- College of Grain and Food science, Henan University of Technology, Zhengzhou, Henan, People's Republic of China
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Kumar A, Chandra R. Ligninolytic enzymes and its mechanisms for degradation of lignocellulosic waste in environment. Heliyon 2020; 6:e03170. [PMID: 32095645 PMCID: PMC7033530 DOI: 10.1016/j.heliyon.2020.e03170] [Citation(s) in RCA: 158] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Revised: 10/04/2019] [Accepted: 12/31/2019] [Indexed: 12/30/2022] Open
Abstract
Ligninolytic enzymes play a key role in degradation and detoxification of lignocellulosic waste in environment. The major ligninolytic enzymes are laccase, lignin peroxidase, manganese peroxidase, and versatile peroxidase. The activities of these enzymes are enhanced by various mediators as well as some other enzymes (feruloyl esterase, aryl-alcohol oxidase, quinone reductases, lipases, catechol 2, 3-dioxygenase) to facilitate the process for degradation and detoxification of lignocellulosic waste in environment. The structurally laccase is isoenzymes with monomeric or dimeric and glycosylation levels (10–45%). This contains four copper ions of three different types. The enzyme catalyzes the overall reaction: 4 benzenediol + O2 to 4 benzosemiquinone + 2H2O. While, lignin peroxidase is a glycoprotein molecular mass of 38–46 kDa containing one mole of iron protoporphyrin IX per one mol of protein, catalyzes the H2O2 dependent oxidative depolymerization of lignin. The manganese peroxidase is a glycosylated heme protein with molecular mass of 40–50kDa. It depolymerizes the lignin molecule in the presence of manganese ion. The versatile peroxidase has broad range substrate sharing typical features of the manganese and lignin peroxidase families. Although ligninolytic enzymes have broad range of industrial application specially the degradation and detoxification of lignocellulosic waste discharged from various industrial activities, its large scale application is still limited due to lack of limited production. Further, the extremophilic properties of ligninolytic enzymes indicated their broad prospects in varied environmental conditions. Therefore it needs more extensive research for understanding its structure and mechanisms for broad range commercial applications.
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Affiliation(s)
- Adarsh Kumar
- Department of Environmental Microbiology, School for Environmental Sciences, Babasaheb Bhimrao Ambedkar (A Central) University, Vidya Vihar, Raebareli Road, Lucknow, Uttar Pradesh, 226025, India
| | - Ram Chandra
- Department of Environmental Microbiology, School for Environmental Sciences, Babasaheb Bhimrao Ambedkar (A Central) University, Vidya Vihar, Raebareli Road, Lucknow, Uttar Pradesh, 226025, India
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25
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Tang S, Liu W, Huang C, Lai C, Fan Y, Yong Q. Improving the enzymatic hydrolysis of larch by coupling water pre-extraction with alkaline hydrogen peroxide post-treatment and adding enzyme cocktail. BIORESOURCE TECHNOLOGY 2019; 285:121322. [PMID: 30965281 DOI: 10.1016/j.biortech.2019.121322] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/02/2019] [Accepted: 04/03/2019] [Indexed: 06/09/2023]
Abstract
Soluble arabinogalactan (AG) in larch leads to reagent waste during its biorefining using oxidative pretreatment strategies. A two-stage pretreatment of water pre-extraction followed by alkaline hydrogen peroxide (AHP) pretreatment was investigated to more efficiently convert larch cellulose into glucose, while also obtaining a value-added AG product stream. The results showed that water pre-extraction increases the lignin selectivity of both NaOH and H2O2 reagents, translating to improved lignin removal and enzymatic hydrolysis yields. This was found to be related to cellulose accessibility alongside the effective consumption of the reagents. Moreover, the addition of mannanase also significantly enhanced enzymatic digestibility of pretreated solid from 81.0% to 97.7% (4% H2O2 charge and 180 °C) when 40 U/g mannanase was supplemented with 20 FPU/g cellulase. In all, it was demonstrated that coupling mannanase with cellulase could improve larch's enzymatic digestibility and overall viability for biorefining processes.
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Affiliation(s)
- Shuo Tang
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China
| | - Wanying Liu
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China
| | - Caoxing Huang
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China
| | - Chenhuan Lai
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China
| | - Yimin Fan
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China
| | - Qiang Yong
- Key Laboratory of Forestry Genetics & Biotechnology (Nanjing Forestry University), Ministry of Education, Nanjing 210037, People's Republic of China; Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Jiangsu Province Key Laboratory of Green Biomass-based Fuels and Chemicals, Nanjing 210037, People's Republic of China.
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Chylenski P, Bissaro B, Sørlie M, Røhr ÅK, Várnai A, Horn SJ, Eijsink VG. Lytic Polysaccharide Monooxygenases in Enzymatic Processing of Lignocellulosic Biomass. ACS Catal 2019. [DOI: 10.1021/acscatal.9b00246] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Piotr Chylenski
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, N-1432 Ås, Norway
| | - Bastien Bissaro
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, N-1432 Ås, Norway
| | - Morten Sørlie
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, N-1432 Ås, Norway
| | - Åsmund K. Røhr
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, N-1432 Ås, Norway
| | - Anikó Várnai
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, N-1432 Ås, Norway
| | - Svein J. Horn
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, N-1432 Ås, Norway
| | - Vincent G.H. Eijsink
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), P.O. Box 5003, N-1432 Ås, Norway
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von Freiesleben P, Spodsberg N, Stenbæk A, Stålbrand H, Krogh KBRM, Meyer AS. Boosting of enzymatic softwood saccharification by fungal GH5 and GH26 endomannanases. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:194. [PMID: 30026809 PMCID: PMC6048861 DOI: 10.1186/s13068-018-1184-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 06/21/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Softwood is a promising feedstock for lignocellulosic biorefineries, but as it contains galactoglucomannan efficient mannan-degrading enzymes are required to unlock its full potential. RESULTS Boosting of the saccharification of pretreated softwood (Canadian lodgepole pine) was investigated for 10 fungal endo-β(1→4)-mannanases (endomannanases) from GH5 and GH26, including 6 novel GH26 enzymes. The endomannanases from Trichoderma reesei (TresMan5A) and Podospora anserina (PansMan26) were investigated with and without their carbohydrate-binding module (CBM). The pH optimum and initial rates of enzyme catalysed hydrolysis were determined on pure β-mannans, including acetylated and deacetylated spruce galactoglucomannan. Melting temperature (Tm) and stability of the endomannanases during prolonged incubations were also assessed. The highest initial rates on the pure mannans were attained by GH26 endomannanases. Acetylation tended to decrease the enzymatic rates to different extents depending on the enzyme. Despite exhibiting low rates on the pure mannan substrates, TresMan5A with CBM1 catalysed highest release among the endomannanases of both mannose and glucose during softwood saccharification. The presence of the CBM1 as well as the catalytic capability of the TresMan5A core module itself seemed to allow fast and more profound degradation of portions of the mannan that led to better cellulose degradation. In contrast, the presence of the CBM35 did not change the performance of PansMan26 in softwood saccharification. CONCLUSIONS This study identified TresMan5A as the best endomannanase for increasing cellulase catalysed glucose release from softwood. Except for the superior performance of TresMan5A, the fungal GH5 and GH26 endomannanases generally performed on par on the lignocellulosic matrix. The work also illustrated the importance of using genuine lignocellulosic substrates rather than simple model substrates when selecting enzymes for industrial biomass applications.
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Affiliation(s)
- Pernille von Freiesleben
- Novozymes A/S, Krogshøjvej 36, 2880 Bagsværd, Denmark
- Protein Chemistry & Enzyme Technology, DTU Bioengineering, Technical University of Denmark, Building 221, 2800 Kgs. Lyngby, Denmark
| | | | - Anne Stenbæk
- Novozymes A/S, Krogshøjvej 36, 2880 Bagsværd, Denmark
| | - Henrik Stålbrand
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, PO Box 124, 221 00 Lund, Sweden
| | | | - Anne S. Meyer
- Protein Chemistry & Enzyme Technology, DTU Bioengineering, Technical University of Denmark, Building 221, 2800 Kgs. Lyngby, Denmark
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28
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Penttilä PA, Imai T, Hemming J, Willför S, Sugiyama J. Enzymatic hydrolysis of biomimetic bacterial cellulose-hemicellulose composites. Carbohydr Polym 2018; 190:95-102. [PMID: 29628264 DOI: 10.1016/j.carbpol.2018.02.051] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 02/05/2018] [Accepted: 02/18/2018] [Indexed: 11/17/2022]
Abstract
The production of biofuels and other chemicals from lignocellulosic biomass is limited by the inefficiency of enzymatic hydrolysis. Here a biomimetic composite material consisting of bacterial cellulose and wood-based hemicelluloses was used to study the effects of hemicelluloses on the enzymatic hydrolysis with a commercial cellulase mixture. Bacterial cellulose synthesized in the presence of hemicelluloses, especially xylan, was found to be more susceptible to enzymatic hydrolysis than hemicellulose-free bacterial cellulose. The reason for the easier hydrolysis could be related to the nanoscale structure of the substrate, particularly the packing of cellulose microfibrils into ribbons or bundles. In addition, small-angle X-ray scattering was used to show that the average nanoscale morphology of bacterial cellulose remained unchanged during the enzymatic hydrolysis. The reported easier enzymatic hydrolysis of bacterial cellulose produced in the presence of wood-based xylan offers new insights to overcome biomass recalcitrance through genetic engineering.
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Affiliation(s)
- Paavo A Penttilä
- Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, 611-0011 Uji, Japan.
| | - Tomoya Imai
- Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, 611-0011 Uji, Japan
| | - Jarl Hemming
- Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Porthansgatan 3-5, 20500 Turku, Finland
| | - Stefan Willför
- Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Porthansgatan 3-5, 20500 Turku, Finland
| | - Junji Sugiyama
- Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, 611-0011 Uji, Japan
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29
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Prajapati BP, Kumar Suryawanshi R, Agrawal S, Ghosh M, Kango N. Characterization of cellulase from Aspergillus tubingensis NKBP-55 for generation of fermentable sugars from agricultural residues. BIORESOURCE TECHNOLOGY 2018; 250:733-740. [PMID: 29223094 DOI: 10.1016/j.biortech.2017.11.099] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 11/28/2017] [Accepted: 11/29/2017] [Indexed: 06/07/2023]
Abstract
The aim of this work was to characterize cellulase from Aspergillus tubingensis NKBP-55 for generation of fermentable sugars from agricultural residues. The strain produced high titres of cellulase (750 U/gds) on copra meal in solid state fermentation (SSF). The enzyme preparation also showed hemicellulolytic activities (U/gds) viz. endo-mannanase (1023), endo-xylanase (167), β-glucosidase (72) and α-galactosidase (54). Zymography revealed presence of six cellulases, six mannanases and one β-glucosidase. It effectively degraded sugarcane bagasse (SCB) and rice straw (RS) releasing xylose, glucose and cellobiose. One cellulase (Cat 1, Mr ∼65 kDa) was purified and characterized. It retained more than 50% activity at 70 °C after 150 mins and its activity was enhanced in the presence of Mn2+ ions (130%) and β-mercaptoethanol (140%). FTIR and 13C CP/MAS NMR analysis of the enzyme treated SCB and RS revealed degradation of cellulose and hemicellulose, while 1H and 13C liquid state NMR experiments confirmed release of glucose.
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Affiliation(s)
- Bhanu Pratap Prajapati
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, MP 470003, India
| | - Rahul Kumar Suryawanshi
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, MP 470003, India
| | - Sarika Agrawal
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, MP 470003, India
| | - Manasi Ghosh
- Department of Physics, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, MP 470003, India
| | - Naveen Kango
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, MP 470003, India.
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Wang Y, Shao Y, Zou X, Yang M, Guo L. Synergistic action between extracellular products from white-rot fungus and cellulase significantly improves enzymatic hydrolysis. Bioengineered 2018; 9:178-185. [PMID: 28384075 PMCID: PMC5972936 DOI: 10.1080/21655979.2017.1308991] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
With a set of perfect extracellular lignocellulolytic enzymes, white-rot fungus has been recognized as playing an important role in the degradation of lignocellulose materials, which leads to the possibility of creating a composite enzymatic system with high hydrolysis efficiency in vitro. Echinodontium taxodii is a promising white-rot fungus for biologic pretreatment. In this study, we extracted the extracellular products of E. taxodii under solid-state fermentation conditions, mixed the extracellular products with cellulase to build a composite enzymatic system, and systematically evaluated the effect of this system on the hydrolysis of acid-pretreated and raw maize stovers. We found that the extracellular products from E. taxodii could significantly improve the hydrolysis efficiency of cellulase, with a synergistic action between the extracellular products and cellulase. Corn stovers treated with extracellular products were suitable for the enzymatic hydrolysis of cellulase. Furthermore, we found that pure proteins from the extracellular products were not sufficient to generate synergistic action. This finding suggests that non-protein substances may also be involved in the synergistic action between the extracellular products and cellulase.
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Affiliation(s)
- Yushan Wang
- a Department of Biotechnology , Heilongjiang Vocational Institute of Ecological Engineering, Heilongjiang Province , China
| | - Yang Shao
- a Department of Biotechnology , Heilongjiang Vocational Institute of Ecological Engineering, Heilongjiang Province , China
| | - Xinyue Zou
- a Department of Biotechnology , Heilongjiang Vocational Institute of Ecological Engineering, Heilongjiang Province , China
| | - Mandi Yang
- a Department of Biotechnology , Heilongjiang Vocational Institute of Ecological Engineering, Heilongjiang Province , China
| | - Lin Guo
- a Department of Biotechnology , Heilongjiang Vocational Institute of Ecological Engineering, Heilongjiang Province , China
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31
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Arnling Bååth J, Martínez-Abad A, Berglund J, Larsbrink J, Vilaplana F, Olsson L. Mannanase hydrolysis of spruce galactoglucomannan focusing on the influence of acetylation on enzymatic mannan degradation. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:114. [PMID: 29713374 PMCID: PMC5907293 DOI: 10.1186/s13068-018-1115-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 04/10/2018] [Indexed: 05/14/2023]
Abstract
BACKGROUND Galactoglucomannan (GGM) is the most abundant hemicellulose in softwood, and consists of a backbone of mannose and glucose units, decorated with galactose and acetyl moieties. GGM can be hydrolyzed into fermentable sugars, or used as a polymer in films, gels, and food additives. Endo-β-mannanases, which can be found in the glycoside hydrolase families 5 and 26, specifically cleave the mannan backbone of GGM into shorter oligosaccharides. Information on the activity and specificity of different mannanases on complex and acetylated substrates is still lacking. The aim of this work was to evaluate and compare the modes of action of two mannanases from Cellvibrio japonicus (CjMan5A and CjMan26A) on a variety of mannan substrates, naturally and chemically acetylated to varying degrees, including naturally acetylated spruce GGM. Both enzymes were evaluated in terms of cleavage patterns and their ability to accommodate acetyl substitutions. RESULTS CjMan5A and CjMan26A demonstrated different substrate preferences on mannan substrates with distinct backbone and decoration structures. CjMan5A action resulted in higher amounts of mannotriose and mannotetraose than that of CjMan26A, which mainly generated mannose and mannobiose as end products. Mass spectrometric analysis of products from the enzymatic hydrolysis of spruce GGM revealed that an acetylated hexotriose was the shortest acetylated oligosaccharide produced by CjMan5A, whereas CjMan26A generated acetylated hexobiose as well as diacetylated oligosaccharides. A low degree of native acetylation did not significantly inhibit the enzymatic action. However, a high degree of chemical acetylation resulted in decreased hydrolyzability of mannan substrates, where reduced substrate solubility seemed to reduce enzyme activity. CONCLUSIONS Our findings demonstrate that the two mannanases from C. japonicus have different cleavage patterns on linear and decorated mannan polysaccharides, including the abundant and industrially important resource spruce GGM. CjMan26A released higher amounts of fermentable sugars suitable for biofuel production, while CjMan5A, producing higher amounts of oligosaccharides, could be a good candidate for the production of oligomeric platform chemicals and food additives. Furthermore, chemical acetylation of mannan polymers was found to be a potential strategy for limiting the biodegradation of mannan-containing materials.
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Affiliation(s)
- Jenny Arnling Bååth
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Antonio Martínez-Abad
- Division of Glycoscience, Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 100 44 Stockholm, Sweden
- Present Address: Department of Analytical Chemistry, Nutrition and Food Sciences, University of Alicante, 03690 Alicante, Spain
| | - Jennie Berglund
- Wallenberg Wood Science Center, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 100 44 Stockholm, Sweden
| | - Johan Larsbrink
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Francisco Vilaplana
- Division of Glycoscience, Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 100 44 Stockholm, Sweden
- Wallenberg Wood Science Center, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 100 44 Stockholm, Sweden
| | - Lisbeth Olsson
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, 412 96 Gothenburg, Sweden
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32
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Action of lytic polysaccharide monooxygenase on plant tissue is governed by cellular type. Sci Rep 2017; 7:17792. [PMID: 29259205 PMCID: PMC5736606 DOI: 10.1038/s41598-017-17938-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 11/28/2017] [Indexed: 11/08/2022] Open
Abstract
Lignocellulosic biomass bioconversion is hampered by the structural and chemical complexity of the network created by cellulose, hemicellulose and lignin. Biological conversion of lignocellulose involves synergistic action of a large array of enzymes including the recently discovered lytic polysaccharide monooxygenases (LPMOs) that perform oxidative cleavage of cellulose. Using in situ imaging by synchrotron UV fluorescence, we have shown that the addition of AA9 LPMO (from Podospora anserina) to cellulases cocktail improves the progression of enzymes in delignified Miscanthus x giganteus as observed at tissular levels. In situ chemical monitoring of cell wall modifications performed by synchrotron infrared spectroscopy during enzymatic hydrolysis demonstrated that the boosting effect of the AA9 LPMO was dependent on the cellular type indicating contrasted recalcitrance levels in plant tissues. Our study provides a useful strategy for investigating enzyme dynamics and activity in plant cell wall to improve enzymatic cocktails aimed at expanding lignocelluloses biorefinery.
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33
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Bombeck PL, Khatri V, Meddeb-Mouelhi F, Montplaisir D, Richel A, Beauregard M. Predicting the most appropriate wood biomass for selected industrial applications: comparison of wood, pulping, and enzymatic treatments using fluorescent-tagged carbohydrate-binding modules. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:293. [PMID: 29225698 PMCID: PMC5718010 DOI: 10.1186/s13068-017-0980-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/26/2017] [Indexed: 05/11/2023]
Abstract
BACKGROUND Lignocellulosic biomass will progressively become the main source of carbon for a number of products as the Earth's oil reservoirs disappear. Technology for conversion of wood fiber into bioproducts (wood biorefining) continues to flourish, and access to reliable methods for monitoring modification of such fibers is becoming an important issue. Recently, we developed a simple, rapid approach for detecting four different types of polymer on the surface of wood fibers. Named fluorescent-tagged carbohydrate-binding module (FTCM), this method is based on the fluorescence signal from carbohydrate-binding modules-based probes designed to recognize specific polymers such as crystalline cellulose, amorphous cellulose, xylan, and mannan. RESULTS Here we used FTCM to characterize pulps made from softwood and hardwood that were prepared using Kraft or chemical-thermo-mechanical pulping. Comparison of chemical analysis (NREL protocol) and FTCM revealed that FTCM results were consistent with chemical analysis of the hemicellulose composition of both hardwood and softwood samples. Kraft pulping increased the difference between softwood and hardwood surface mannans, and increased xylan exposure. This suggests that Kraft pulping leads to exposure of xylan after removal of both lignin and mannan. Impact of enzyme cocktails from Trichoderma reesei (Celluclast 1.5L) and from Aspergillus sp. (Carezyme 1000L) was investigated by analysis of hydrolyzed sugars and by FTCM. Both enzymes preparations released cellobiose and glucose from pulps, with the cocktail from Trichoderma being the most efficient. Enzymatic treatments were not as effective at converting chemical-thermomechanical pulps to simple sugars, regardless of wood type. FTCM revealed that amorphous cellulose was the primary target of either enzyme preparation, which resulted in a higher proportion of crystalline cellulose on the surface after enzymatic treatment. FTCM confirmed that enzymes from Aspergillus had little impact on exposed hemicelluloses, but that enzymes from the more aggressive Trichoderma cocktail reduced hemicelluloses at the surface. CONCLUSIONS Overall, this study indicates that treatment with enzymes from Trichoderma is appropriate for generating crystalline cellulose at fiber surface. Applications such as nanocellulose or composites requiring chemical resistance would benefit from this enzymatic treatment. The milder enzyme mixture from Aspergillus allowed for removal of amorphous cellulose while preserving hemicelluloses at fiber surface, which makes this treatment appropriate for new paper products where surface chemical responsiveness is required.
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Affiliation(s)
- Pierre-Louis Bombeck
- AgroBioChem Department, Laboratory of Biomass and Green Technologies, University of Liège, Gembloux Agro-Bio Tech, 5030 Gembloux, Belgium
| | - Vinay Khatri
- Université du Québec à Trois-Rivières, Centre de Recherche sur les Matériaux Lignocellulosiques, C.P. 500, Trois-Rivières, QC G9A 5H7 Canada
- PROTEO, Université Laval, Québec, QC G1V 0A6 Canada
| | - Fatma Meddeb-Mouelhi
- Université du Québec à Trois-Rivières, Centre de Recherche sur les Matériaux Lignocellulosiques, C.P. 500, Trois-Rivières, QC G9A 5H7 Canada
- PROTEO, Université Laval, Québec, QC G1V 0A6 Canada
| | - Daniel Montplaisir
- Département de Chimie, Biochimie et Physique, Université du Québec à Trois-Rivières, C.P. 500, Trois-Rivières, QC G9A 5H7 Canada
| | - Aurore Richel
- AgroBioChem Department, Laboratory of Biomass and Green Technologies, University of Liège, Gembloux Agro-Bio Tech, 5030 Gembloux, Belgium
| | - Marc Beauregard
- Université du Québec à Trois-Rivières, Centre de Recherche sur les Matériaux Lignocellulosiques, C.P. 500, Trois-Rivières, QC G9A 5H7 Canada
- PROTEO, Université Laval, Québec, QC G1V 0A6 Canada
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Cortes-Tolalpa L, Salles JF, van Elsas JD. Bacterial Synergism in Lignocellulose Biomass Degradation - Complementary Roles of Degraders As Influenced by Complexity of the Carbon Source. Front Microbiol 2017; 8:1628. [PMID: 29067002 PMCID: PMC5641323 DOI: 10.3389/fmicb.2017.01628] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 08/10/2017] [Indexed: 01/23/2023] Open
Abstract
Lignocellulosic biomass (LCB) is an attractive source of carbon for the production of sugars and other chemicals. Due to its inherent complexity and heterogeneity, efficient biodegradation requires the actions of different types of hydrolytic enzymes. In nature, complex microbial communities that work efficiently and often synergistically accomplish degradation. Studying such synergisms in LCB degradation is fundamental for the establishment of an optimal biological degradation process. Here, we examine the wheat straw degradation potential of synthetic microbial consortia composed of bacteria and fungi. Growth of, and enzyme secretion by, monocultures of degrader strains were studied in aerobic cultures using wheat straw as the sole carbon and energy source. To investigate synergism, co-cultures were constructed from selected strains and their performance was tested in comparison with the respective monocultures. In monoculture, each organism – with a typical enzymatic profile – was found to mainly consume the cellulose part of the substrate. One strain, Flavobacterium ginsengisoli so9, displayed an extremely high degradation capacity, as measured by its secreted enzymes. Among 13 different co-cultures, five presented synergisms. These included four bacterial bicultures and one bacterial–fungal triculture. The highest level of synergism was found in a Citrobacter freundii/Sphingobacterium multivorum biculture, which revealed an 18.2-fold increase of the produced biomass. As compared to both monocultures, this bacterial pair showed significantly increased enzymatic activities, in particular of cellobiohydrolases, mannosidases, and xylosidases. Moreover, the synergism was unique to growth on wheat straw, as it was completely absent in glucose-grown bicultures. Spent supernatants of either of the two partners were found to stimulate the growth on wheat straw of the counterpart organism, in a directional manner. Thus, the basis of the LCB-specific synergism might lie in the specific release of compounds or agents by S. multivorum w15 that promote the activity of C. freundii so4 and vice versa.
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Affiliation(s)
- Larisa Cortes-Tolalpa
- Department of Microbial Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, Netherlands
| | - Joana F Salles
- Department of Microbial Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, Netherlands
| | - Jan Dirk van Elsas
- Department of Microbial Ecology, Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, Netherlands
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Malgas S, Thoresen M, van Dyk JS, Pletschke BI. Time dependence of enzyme synergism during the degradation of model and natural lignocellulosic substrates. Enzyme Microb Technol 2017; 103:1-11. [DOI: 10.1016/j.enzmictec.2017.04.007] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 04/18/2017] [Accepted: 04/21/2017] [Indexed: 10/19/2022]
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Abstract
Fungi and fungal enzymes play important roles in the new bioeconomy. Enzymes from filamentous fungi can unlock the potential of recalcitrant lignocellulose structures of plant cell walls as a new resource, and fungi such as yeast can produce bioethanol from the sugars released after enzyme treatment. Such processes reflect inherent characteristics of the fungal way of life, namely, that fungi as heterotrophic organisms must break down complex carbon structures of organic materials to satisfy their need for carbon and nitrogen for growth and reproduction. This chapter describes major steps in the conversion of plant biomass to value-added products. These products provide a basis for substituting fossil-derived fuels, chemicals, and materials, as well as unlocking the biomass potential of the agricultural harvest to yield more food and feed. This article focuses on the mycological basis for the fungal contribution to biorefinery processes, which are instrumental for improved resource efficiency and central to the new bioeconomy. Which types of processes, inherent to fungal physiology and activities in nature, are exploited in the new industrial processes? Which families of the fungal kingdom and which types of fungal habitats and ecological specializations are hot spots for fungal biomass conversion? How can the best fungal enzymes be found and optimized for industrial use? How can they be produced most efficiently-in fungal expression hosts? How have industrial biotechnology and biomass conversion research contributed to mycology and environmental research? Future perspectives and approaches are listed, highlighting the importance of fungi in development of the bioeconomy.
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Identification of multienzymatic complexes in the Clonostachys byssicola secretomes produced in response to different lignocellulosic carbon sources. J Biotechnol 2017; 254:51-58. [PMID: 28610997 DOI: 10.1016/j.jbiotec.2017.06.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 05/26/2017] [Accepted: 06/05/2017] [Indexed: 01/29/2023]
Abstract
Multienzymatic complexes with plant lignocellulose-degrading activities have recently been identified in filamentous fungi secretomes. Such complexes have potential biotechnological applications in the degradation of agro-industrial residues. Fungal species from the Clonostachys genus have been intensively investigated as biocontrol agents; however so far their use as producers of lignocellulose-degrading enzymes has not been extensively explored. Secretomes of Clonostachys byssicola following growth on different carbon sources (passion fruit peel, soybean hulls, cotton gin trash, banana stalk, sugarcane bagasse, orange peel, and a composition of soybean hulls: cotton gin trash:orange peel) were subjected to enzymatic assays. Remarkable differences were observed among the samples, especially regarding levels of mannanase and pectinase activities. Secretomes were then subjected to Blue Native PAGE in order to resolve putative protein complexes which subsequently had their composition revealed by trypsin digestion followed by LC-MS/MS analysis. The protein bands (named I, II, III and IV) were shown to be composed by holocellulolytic enzymes, mainly cellulases and xylanases as well as proteins involved in biocontrol processes, such as chitinases and proteases. The high diversity of proteins found in these multicatalytic assemblies confirms C. byssicola as a novel source of plant biomass-degrading enzymes.
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Chylenski P, Forsberg Z, Ståhlberg J, Várnai A, Lersch M, Bengtsson O, Sæbø S, Horn SJ, Eijsink VGH. Development of minimal enzyme cocktails for hydrolysis of sulfite-pulped lignocellulosic biomass. J Biotechnol 2017; 246:16-23. [PMID: 28219736 DOI: 10.1016/j.jbiotec.2017.02.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 01/26/2017] [Accepted: 02/13/2017] [Indexed: 01/02/2023]
Abstract
Despite recent progress, saccharification of lignocellulosic biomass is still a major cost driver in biorefining. In this study, we present the development of minimal enzyme cocktails for hydrolysis of Norway spruce and sugarcane bagasse, which were pretreated using the so-called BALI™ process, which is based on sulfite pulping technology. Minimal enzyme cocktails were composed using several glycoside hydrolases purified from the industrially relevant filamentous fungus Trichoderma reesei and a purified commercial β-glucosidase from Aspergillus niger. The contribution of in-house expressed lytic polysaccharide monooxygenases (LPMOs) was also tested, since oxidative cleavage of cellulose by such LPMOs is known to be beneficial for conversion efficiency. We show that the optimized cocktails permit efficient saccharification at reasonable enzyme loadings and that the effect of the LPMOs is substrate-dependent. Using a cocktail comprising only four enzymes, glucan conversion for Norway spruce reached >80% at enzyme loadings of 8mg/g glucan, whereas almost 100% conversion was achieved at 16mg/g.
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Affiliation(s)
- Piotr Chylenski
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Zarah Forsberg
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Jerry Ståhlberg
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Anikó Várnai
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | | | | | - Solve Sæbø
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Svein Jarle Horn
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Vincent G H Eijsink
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway.
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Kameshwar AKS, Qin W. Metadata Analysis of Phanerochaete chrysosporium Gene Expression Data Identified Common CAZymes Encoding Gene Expression Profiles Involved in Cellulose and Hemicellulose Degradation. Int J Biol Sci 2017; 13:85-99. [PMID: 28123349 PMCID: PMC5264264 DOI: 10.7150/ijbs.17390] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 10/10/2016] [Indexed: 01/04/2023] Open
Abstract
In literature, extensive studies have been conducted on popular wood degrading white rot fungus, Phanerochaete chrysosporium about its lignin degrading mechanisms compared to the cellulose and hemicellulose degrading abilities. This study delineates cellulose and hemicellulose degrading mechanisms through large scale metadata analysis of P. chrysosporium gene expression data (retrieved from NCBI GEO) to understand the common expression patterns of differentially expressed genes when cultured on different growth substrates. Genes encoding glycoside hydrolase classes commonly expressed during breakdown of cellulose such as GH-5,6,7,9,44,45,48 and hemicellulose are GH-2,8,10,11,26,30,43,47 were found to be highly expressed among varied growth conditions including simple customized and complex natural plant biomass growth mediums. Genes encoding carbohydrate esterase class enzymes CE (1,4,8,9,15,16) polysaccharide lyase class enzymes PL-8 and PL-14, and glycosyl transferases classes GT (1,2,4,8,15,20,35,39,48) were differentially expressed in natural plant biomass growth mediums. Based on these results, P. chrysosporium, on natural plant biomass substrates was found to express lignin and hemicellulose degrading enzymes more than cellulolytic enzymes except GH-61 (LPMO) class enzymes, in early stages. It was observed that the fate of P. chrysosporium transcriptome is significantly affected by the wood substrate provided. We believe, the gene expression findings in this study plays crucial role in developing genetically efficient microbe with effective cellulose and hemicellulose degradation abilities.
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Affiliation(s)
| | - Wensheng Qin
- Department of Biology, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, P7B 5E1, Canada
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Arola S, Linder MB. Binding of cellulose binding modules reveal differences between cellulose substrates. Sci Rep 2016; 6:35358. [PMID: 27748440 PMCID: PMC5066208 DOI: 10.1038/srep35358] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 09/28/2016] [Indexed: 11/20/2022] Open
Abstract
The interaction between cellulase enzymes and their substrates is of central importance to several technological and scientific challenges. Here we report that the binding of cellulose binding modules (CBM) from Trichoderma reesei cellulases Cel6A and Cel7A show a major difference in how they interact with substrates originating from wood compared to bacterial cellulose. We found that the CBM from TrCel7A recognizes the two substrates differently and as a consequence shows an unexpected way of binding. We show that the substrate has a large impact on the exchange rate of the studied CBM, and moreover, CBM-TrCel7A seems to have an additional mode of binding on wood derived cellulose but not on cellulose originating from bacterial source. This mode is not seen in double CBM (DCBM) constructs comprising both CBM-TrCel7A and CBM-TrCel6A. The linker length of DCBMs affects the binding properties, and slows down the exchange rates of the proteins and thus, can be used to analyze the differences between the single CBM. These results have impact on the cellulase research and offer new understanding on how these industrially relevant enzymes act.
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Affiliation(s)
- Suvi Arola
- School of Science, Aalto University, P. O. Box 11100, FI-00076, Aalto, Finland
- School of Chemical Technology, Aalto University, P.O. Box 16100, FI-00076, Aalto, Finland
- VTT, Technical Research Centre of Finland, Bio and process technology, P.O.Box 1000, FIN–02044 VTT, Finland
| | - Markus B. Linder
- School of Chemical Technology, Aalto University, P.O. Box 16100, FI-00076, Aalto, Finland
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Tonin F, Rosini E, Piubelli L, Sanchez-Amat A, Pollegioni L. Different recombinant forms of polyphenol oxidase A, a laccase from Marinomonas mediterranea. Protein Expr Purif 2016; 123:60-9. [DOI: 10.1016/j.pep.2016.03.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 03/23/2016] [Accepted: 03/29/2016] [Indexed: 11/25/2022]
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Maitan-Alfenas GP, Oliveira MB, Nagem RAP, de Vries RP, Guimarães VM. Characterization and biotechnological application of recombinant xylanases from Aspergillus nidulans. Int J Biol Macromol 2016; 91:60-7. [PMID: 27235731 DOI: 10.1016/j.ijbiomac.2016.05.065] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/14/2016] [Accepted: 05/17/2016] [Indexed: 02/06/2023]
Abstract
Two xylanases from Aspergillus nidulans, XlnB and XlnC, were expressed in Pichia pastoris, purified and characterized. XlnB and XlnC achieved maximal activities at 60°C and pH 7.5 and at 50°C and pH 6.0, respectively. XlnB showed to be very thermostable by maintaining 50% of its original activity after 49h incubated at 50°C. XlnB had its highest activity against wheat arabinoxylan while XlnC had the best activity against beechwood xylan. Both enzymes were completely inhibited by SDS and HgCl2. Xylotriose at 1mg/ml also totally inibited XlnB activity. TLC analysis showed that the main product of beechwood xylan hydrolysis by XlnB and XlnC was xylotetraose. An additive effect was shown between XlnB and XlnC and the xylanases of two tested commercial cocktails. Sugarcane bagasse saccharification results showed that these two commercial enzymatic cocktails were able to release more glucose and xylose after supplementation with XlnB and XlnC.
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Affiliation(s)
- Gabriela P Maitan-Alfenas
- Department of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, MG, Brazil; Fungal Physiology, CBS-KNAW Fungal Biodiversity Centre & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands.
| | - Mariana B Oliveira
- Department of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, MG, Brazil; Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Ronaldo A P Nagem
- Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Ronald P de Vries
- Fungal Physiology, CBS-KNAW Fungal Biodiversity Centre & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Valéria M Guimarães
- Department of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, MG, Brazil
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Katsimpouras C, Dimarogona M, Petropoulos P, Christakopoulos P, Topakas E. A thermostable GH26 endo-β-mannanase from Myceliophthora thermophila capable of enhancing lignocellulose degradation. Appl Microbiol Biotechnol 2016; 100:8385-97. [PMID: 27193267 DOI: 10.1007/s00253-016-7609-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 04/24/2016] [Accepted: 05/01/2016] [Indexed: 10/21/2022]
Abstract
The endomannanase gene em26a from the thermophilic fungus Myceliophthora thermophila, belonging to the glycoside hydrolase family 26, was functionally expressed in the methylotrophic yeast Pichia pastoris. The putative endomannanase, dubbed MtMan26A, was purified to homogeneity (60 kDa) and subsequently characterized. The optimum pH and temperature for the enzymatic activity of MtMan26A were 6.0 and 60 °C, respectively. MtMan26A showed high specific activity against konjac glucomannan and carob galactomannan, while it also exhibited high thermal stability with a half-life of 14.4 h at 60 °C. Thermostability is of great importance, especially in industrial processes where harsh conditions are employed. With the aim of better understanding its structure-function relationships, a homology model of MtMan26A was constructed, based on the crystallographic structure of a close homologue. Finally, the addition of MtMan26A as a supplement to the commercial enzyme mixture Celluclast® 1.5 L and Novozyme® 188 resulted in enhanced enzymatic hydrolysis of pretreated beechwood sawdust, improving the release of total reducing sugars and glucose by 13 and 12 %, respectively.
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Affiliation(s)
- Constantinos Katsimpouras
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens, 15780, Greece
| | - Maria Dimarogona
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens, 15780, Greece
| | - Pericles Petropoulos
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens, 15780, Greece
| | - Paul Christakopoulos
- Biochemical and Chemical Process Engineering, Division of Sustainable Process Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187, Luleå, Sweden
| | - Evangelos Topakas
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens, 15780, Greece.
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Li Y, Sun Z, Ge X, Zhang J. Effects of lignin and surfactant on adsorption and hydrolysis of cellulases on cellulose. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:20. [PMID: 26816530 PMCID: PMC4727347 DOI: 10.1186/s13068-016-0434-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/08/2016] [Indexed: 05/03/2023]
Abstract
BACKGROUND Considerable works have been reported concerning the obstruction of enzymatic hydrolysis efficiency by lignin. However, there is a lack of information about the influence of lignin on the adsorption of cellulases on cellulose, along with the hydrolytic activity of the cellulases adsorbed on lignin. In addition, limited discovery has been reported about the influence of additives on cellulase desorption from lignin and lignocellulosic materials. In this work, the effects of lignin on cellulase adsorption and hydrolysis of Avicel were investigated and the effects of Tween 80 on cellulases adsorption and desorption on/from lignin and corn stover were explored. RESULTS The results showed that the maximum adsorption capacity of Avicel reduced from 276.9 to 179.7 and 112.1 mg/g cellulose with the addition of 1 and 10 mg lignin per gram Avicel, which indicated that lignin adsorbed on Avicel reduced surface area of cellulose and lignin available for cellulases. Cellulases adsorbed on lignin could be released by reaching new adsorption equilibrium between lignin and supernatants. In addition, cellulases desorbed from lignin still possess hydrolytic capacity. Tween 80 could adsorb onto both lignin and corn stover, and reduce the cellulase adsorption on them. Furthermore, Tween 80 could enhance desorption of cellulases from both lignin and corn stover, which might be due to the competitive adsorption between cellulases and Tween 80 on them. CONCLUSIONS The presence of lignin decreased the maximum adsorption capacity of cellulases on cellulose and the cellulases adsorbed on lignin could be released to supernatant, exhibiting hydrolytic activity. Tween 80 could alleviate the adsorption of cellulases and enhanced desorption of cellulases on/from lignin and corn stover. The conclusions of this work help us further understanding the role of lignin in the reduction of adsorption of cellulases on substrates, and the function of additives in cellulases adsorption and desorption on/from lignin and substrates.
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Affiliation(s)
- Yanfei Li
- College of Forestry, Northwest A and F University, 3 Taicheng Road, Yangling, 712100 China
| | - Zongping Sun
- College of Forestry, Northwest A and F University, 3 Taicheng Road, Yangling, 712100 China
| | - Xiaoyan Ge
- College of Forestry, Northwest A and F University, 3 Taicheng Road, Yangling, 712100 China
| | - Junhua Zhang
- College of Forestry, Northwest A and F University, 3 Taicheng Road, Yangling, 712100 China
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Rytioja J, Hildén K, Mäkinen S, Vehmaanperä J, Hatakka A, Mäkelä MR. Saccharification of Lignocelluloses by Carbohydrate Active Enzymes of the White Rot Fungus Dichomitus squalens. PLoS One 2015; 10:e0145166. [PMID: 26660105 PMCID: PMC4682842 DOI: 10.1371/journal.pone.0145166] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 11/30/2015] [Indexed: 01/11/2023] Open
Abstract
White rot fungus Dichomitus squalens is an efficient lignocellulose degrading basidiomycete and a promising source for new plant cell wall polysaccharides depolymerizing enzymes. In this work, we focused on cellobiohydrolases (CBHs) of D. squalens. The native CBHI fraction of the fungus, consisting three isoenzymes, was purified and it maintained the activity for 60 min at 50°C, and was stable in acidic pH. Due to the lack of enzyme activity assay for detecting only CBHII activity, CBHII of D. squalens was produced recombinantly in an industrially important ascomycete host, Trichoderma reesei. CBH enzymes of D. squalens showed potential in hydrolysis of complex lignocellulose substrates sugar beet pulp and wheat bran, and microcrystalline cellulose, Avicel. Recombinant CBHII (rCel6A) of D. squalens hydrolysed all the studied plant biomasses. Compared to individual activities, synergistic effect between rCel6A and native CBHI fraction of D. squalens was significant in the hydrolysis of Avicel. Furthermore, the addition of laccase to the mixture of CBHI fraction and rCel6A significantly enhanced the amount of released reducing sugars from sugar beet pulp. Especially, synergy between individual enzymes is a crucial factor in the tailor-made enzyme mixtures needed for hydrolysis of different plant biomass feedstocks. Our data supports the importance of oxidoreductases in improved enzyme cocktails for lignocellulose saccharification.
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Affiliation(s)
- Johanna Rytioja
- Department of Food and Environmental Sciences, Division of Microbiology and Biotechnology, University of Helsinki, Helsinki, Finland
| | - Kristiina Hildén
- Department of Food and Environmental Sciences, Division of Microbiology and Biotechnology, University of Helsinki, Helsinki, Finland
| | | | | | - Annele Hatakka
- Department of Food and Environmental Sciences, Division of Microbiology and Biotechnology, University of Helsinki, Helsinki, Finland
| | - Miia R. Mäkelä
- Department of Food and Environmental Sciences, Division of Microbiology and Biotechnology, University of Helsinki, Helsinki, Finland
- * E-mail:
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Laothanachareon T, Bunterngsook B, Suwannarangsee S, Eurwilaichitr L, Champreda V. Synergistic action of recombinant accessory hemicellulolytic and pectinolytic enzymes to Trichoderma reesei cellulase on rice straw degradation. BIORESOURCE TECHNOLOGY 2015; 198:682-690. [PMID: 26433794 DOI: 10.1016/j.biortech.2015.09.053] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 09/12/2015] [Accepted: 09/14/2015] [Indexed: 06/05/2023]
Abstract
Synergism between core cellulases and accessory hydrolytic/non-hydrolytic enzymes is the basis of efficient hydrolysis of lignocelluloses. In this study, the synergistic action of three recombinant accessory enzymes, namely GH62 α-l-arabinofuranosidase (ARA), CE8 pectin esterase (PET), and GH10 endo-1,4-beta-xylanase (XYL) from Aspergillus aculeatus expressed in Pichia pastoris to a commercial Trichoderma reesei cellulase (Accellerase® 1500; ACR) on hydrolysis of alkaline pretreated rice straw was studied using a mixture design approach. Applying the full cubic model, the optimal ratio of quaternary enzyme mixture was predicted to be ACR:ARA:PET:XYL of 0.171:0.079:0.100:0.150, which showed a glucose releasing efficiency of 0.173 gglc/FPU, higher than the binary ACR:XYL mixture (0.122 gglc/FPU) and ACR alone (0.081 gglc/FPU) leading to a 47.3% increase in glucose yield compared with that from ACR at the same cellulase dosage. The result demonstrates the varying degree of synergism of accessory enzymes to cellulases useful for developing tailor-made enzyme systems for bio-industry.
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Affiliation(s)
- Thanaporn Laothanachareon
- Enzyme Technology Laboratory and Integrative Biorefinery Laboratory, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, Thailand Science Park, 113 Pahonyothin Road, Pathumthani 12120, Thailand
| | - Benjarat Bunterngsook
- Enzyme Technology Laboratory and Integrative Biorefinery Laboratory, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, Thailand Science Park, 113 Pahonyothin Road, Pathumthani 12120, Thailand
| | - Surisa Suwannarangsee
- Enzyme Technology Laboratory and Integrative Biorefinery Laboratory, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, Thailand Science Park, 113 Pahonyothin Road, Pathumthani 12120, Thailand
| | - Lily Eurwilaichitr
- Enzyme Technology Laboratory and Integrative Biorefinery Laboratory, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, Thailand Science Park, 113 Pahonyothin Road, Pathumthani 12120, Thailand
| | - Verawat Champreda
- Enzyme Technology Laboratory and Integrative Biorefinery Laboratory, National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency, Thailand Science Park, 113 Pahonyothin Road, Pathumthani 12120, Thailand.
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Wang Y, Song X, Zhang S, Li J, Shu Z, He C, Huang Q, Yao L. Improving the activity of Trichoderma reesei cel7B through stabilizing the transition state. Biotechnol Bioeng 2015; 113:1171-7. [PMID: 26616246 DOI: 10.1002/bit.25887] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Revised: 11/11/2015] [Accepted: 11/17/2015] [Indexed: 11/10/2022]
Abstract
Trichoderma reesei (Tr.) cellulases, which convert cellulose to reducing sugars, are a promising catalyst used in the lignocellulosic biofuel production. Improving Tr. cellulases activity, though very difficult, is highly desired due to the recalcitrance of lignocellulose. Meanwhile, it is preferable to enhance the cellulase's promiscuity so that substrates other than cellulose can also be hydrolyzed. In this work, an attempt is made to improve the catalytic activity of a major endogluanase Tr. Cel7B against xylan which crosslinks with cellulose in lignocellulose. By using quantum mechanics/molecular mechanics (QM/MM) molecular dynamics (MD) simulations, the transition state of the xylo-oligosaccharide hydrolysis is identified. Then, mutations are introduced and their effect on the transition state stabilization is ranked based on the free energy calculations. Seven top ranked mutants are evaluated experimentally. Three mutants A208Q, A222D, and G230R show a higher activity than the wild-type Tr. Cel7B in the hydrolysis of xylan (by up to 47%) as well as filter paper (by up to 50%). The combination of the single mutants can further improve the enzyme activity. Our work demonstrates that the free energy method is effective in engineering the Tr. Cel7B activity against xylan and cellulose, and thus may also be useful for improving the activity of other Tr. cellulases. Biotechnol. Bioeng. 2016;113: 1171-1177. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Yefei Wang
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.,Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China
| | - Xiangfei Song
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.,Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China
| | - Shujun Zhang
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.,Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China
| | - Jingwen Li
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.,Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China
| | - Zhiyu Shu
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.,Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China
| | - Chunyan He
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.,Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China
| | - Qingshan Huang
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.,Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China
| | - Lishan Yao
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China. .,Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266061, China.
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von Freiesleben P, Spodsberg N, Blicher TH, Anderson L, Jørgensen H, Stålbrand H, Meyer AS, Krogh KBRM. An Aspergillus nidulans GH26 endo-β-mannanase with a novel degradation pattern on highly substituted galactomannans. Enzyme Microb Technol 2015; 83:68-77. [PMID: 26777252 DOI: 10.1016/j.enzmictec.2015.10.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 10/04/2015] [Accepted: 10/31/2015] [Indexed: 01/17/2023]
Abstract
The activity and substrate degradation pattern of a novel Aspergillus nidulans GH26 endo-β-mannanase (AnMan26A) was investigated using two galactomannan substrates with varying amounts of galactopyranosyl residues. The AnMan26A was characterized in parallel with the GH26 endomannanase from Podospora anserina (PaMan26A) and three GH5 endomannanases from A. nidulans and Trichoderma reesei (AnMan5A, AnMan5C and TrMan5A). The initial rates and the maximal degree of enzymatically catalyzed conversion of locust bean gum and guar gum galactomannans were determined. The hydrolysis product profile at maximal degree of conversion was determined using DNA sequencer-Assisted Saccharide analysis in High throughput (DASH). This is the first reported use of this method for analyzing galactomannooligosaccharides. AnMan26A and PaMan26A were found to have a novel substrate degradation pattern on the two galactomannan substrates. On the highly substituted guar gum AnMan26A and PaMan26A reached 35-40% as their maximal degree of conversion whereas the three tested GH5 endomannanases only reached 8-10% as their maximal degree of conversion. α-Galactosyl-mannose was identified as the dominant degradation product resulting from AnMan26A and PaMan26A action on guar gum, strongly indicating that these two enzymes can accommodate galactopyranosyl residues in the -1 and in the +1 subsite. The degradation of α-6(4)-6(3)-di-galactosyl-mannopentaose by AnMan26A revealed accommodation of galactopyranosyl residues in the -2, -1 and +1 subsite of the enzyme. Accommodation of galactopyranosyl residues in subsites -2 and +1 has not been observed for other characterized endomannanases to date. Docking analysis of galactomannooligosaccharides in available crystal structures and homology models supported the conclusions drawn from the experimental results. This newly discovered diversity of substrate degradation patterns demonstrates an expanded functionality of fungal endomannanases, than hitherto reported.
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Affiliation(s)
- Pernille von Freiesleben
- Novozymes A/S, Krogshøjvej 36, 2880 Bagsværd, Denmark; Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Building 229, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | | | | | - Lars Anderson
- Novozymes A/S, Krogshøjvej 36, 2880 Bagsværd, Denmark
| | - Henning Jørgensen
- Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Building 229, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Henrik Stålbrand
- Department of Biochemistry and Structural Biology, Center for Molecular Protein Science, Lund University, PO Box 124, SE-221 00 Lund, Sweden
| | - Anne S Meyer
- Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Building 229, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.
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49
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Maitan-Alfenas GP, Visser EM, Alfenas RF, Nogueira BRG, de Campos GG, Milagres AF, de Vries RP, Guimarães VM. The influence of pretreatment methods on saccharification of sugarcane bagasse by an enzyme extract from Chrysoporthe cubensis and commercial cocktails: A comparative study. BIORESOURCE TECHNOLOGY 2015; 192:670-676. [PMID: 26094192 DOI: 10.1016/j.biortech.2015.05.109] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 05/27/2015] [Accepted: 05/28/2015] [Indexed: 06/04/2023]
Abstract
Biomass enzymatic hydrolysis depends on the pretreatment methods employed, the composition of initial feedstock and the enzyme cocktail used to release sugars for subsequent fermentation into ethanol. In this study, sugarcane bagasse was pretreated with 1% H2SO4 and 1% NaOH and the biomass saccharification was performed with 8% solids loading using 10 FPase units/g of bagasse of the enzymatic extract from Chrysoporthe cubensis and three commercial cocktails for a comparative study. Overall, the best glucose and xylose release was obtained from alkaline pretreated sugarcane bagasse. The C. cubensis extract promoted higher release of glucose (5.32 g/L) and xylose (9.00 g/L) than the commercial mixtures. Moreover, the C. cubensis extract presented high specific enzyme activities when compared to commercial cocktails mainly concerning to endoglucanase (331.84 U/mg of protein), β-glucosidase (29.48 U/mg of protein), β-xylosidase (2.95 U/mg of protein), pectinase (127.46 U/mg of protein) and laccase (2.49 U/mg of protein).
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Affiliation(s)
- Gabriela Piccolo Maitan-Alfenas
- Department of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Av. PH Rolfs, s/n, 36570-900 Viçosa, MG, Brazil; CBS-KNAW Fungal Biodiversity Centre, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Evan Michael Visser
- Department of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Av. PH Rolfs, s/n, 36570-900 Viçosa, MG, Brazil
| | - Rafael Ferreira Alfenas
- Department of Forest Engineering, Universidade Federal de Mato Grosso, Av. Alexandre Ferronato, 1200, 78557-267 Sinop, MT, Brazil
| | - Bráulio Ris G Nogueira
- Department of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Av. PH Rolfs, s/n, 36570-900 Viçosa, MG, Brazil
| | - Guilherme Galvão de Campos
- Department of Biotechnology, Escola de Engenharia de Lorena, Universidade de São Paulo, 12602-810 Lorena, SP, Brazil
| | - Adriane Ferreira Milagres
- Department of Biotechnology, Escola de Engenharia de Lorena, Universidade de São Paulo, 12602-810 Lorena, SP, Brazil
| | - Ronald P de Vries
- CBS-KNAW Fungal Biodiversity Centre, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Valéria Monteze Guimarães
- Department of Biochemistry and Molecular Biology, Universidade Federal de Viçosa, Av. PH Rolfs, s/n, 36570-900 Viçosa, MG, Brazil.
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50
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Recombinant Trichoderma harzianum endoglucanase I (Cel7B) is a highly acidic and promiscuous carbohydrate-active enzyme. Appl Microbiol Biotechnol 2015; 99:9591-604. [DOI: 10.1007/s00253-015-6772-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 06/09/2015] [Accepted: 06/12/2015] [Indexed: 12/11/2022]
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