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Thongbunrod N, Chaiprasert P. Efficient methane production from agro-industrial residues using anaerobic fungal-rich consortia. World J Microbiol Biotechnol 2024; 40:239. [PMID: 38862848 DOI: 10.1007/s11274-024-04050-7] [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: 04/02/2024] [Accepted: 06/09/2024] [Indexed: 06/13/2024]
Abstract
Anaerobic digestion (AD) emerges as a pivotal technique in climate change mitigation, transforming organic materials into biogas, a renewable energy form. This process significantly impacts energy production and waste management, influencing greenhouse gas emissions. Traditional research has largely focused on anaerobic bacteria and methanogens for methane production. However, the potential of anaerobic lignocellulolytic fungi for degrading lignocellulosic biomass remains less explored. In this study, buffalo rumen inocula were enriched and acclimatized to improve lignocellulolytic hydrolysis activity. Two consortia were established: the anaerobic fungi consortium (AFC), selectively enriched for fungi, and the anaerobic lignocellulolytic microbial consortium (ALMC). The consortia were utilized to create five distinct microbial cocktails-AF0, AF20, AF50, AF80, and AF100. These cocktails were formulated based on varying of AFC and ALMC by weights (w/w). Methane production from each cocktail of lignocellulosic biomasses (cassava pulp and oil palm residues) was evaluated. The highest methane yields of CP, EFB, and MFB were obtained at 337, 215, and 54 mL/g VS, respectively. Cocktails containing a mix of anaerobic fungi, hydrolytic bacteria (Sphingobacterium sp.), syntrophic bacteria (Sphaerochaeta sp.), and hydrogenotrophic methanogens produced 2.1-2.6 times higher methane in cassava pulp and 1.1-1.2 times in oil palm empty fruit bunch compared to AF0. All cocktails effectively produced methane from oil palm empty fruit bunch due to its lipid content. However, methane production ceased after 3 days when oil palm mesocarp fiber was used, due to long-chain fatty acid accumulation. Anaerobic fungi consortia showed effective lignocellulosic and starchy biomass degradation without inhibition due to organic acid accumulation. These findings underscore the potential of tailored microbial cocktails for enhancing methane production from diverse lignocellulosic substrates.
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Affiliation(s)
- Nitiya Thongbunrod
- Biotechnology Program, School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Pawinee Chaiprasert
- Biotechnology Program, School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand.
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2
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Riyadi FA, Azman NF, Nadia Md Akhir F, Othman N, Hara H. Identification and characterization of lignin depolymerization enzymes in Bacillus subtilis strain S11Y isolated from a tropical environment in Malaysia. J GEN APPL MICROBIOL 2024; 69:278-286. [PMID: 37612074 DOI: 10.2323/jgam.2023.08.003] [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] [Indexed: 08/25/2023]
Abstract
Biological pretreatment using microbial enzymes appears to be the most promising pre-treatment technology for the breakdown of recalcitrant lignin structure. This research focuses on the identification and characterization of lignin-depolymerizing enzymes in Bacillus subtilis strain S11Y, previously isolated from palm oil wastes in Malaysia. The draft genome sequences of this highly lignin-depolymerizing strain revealed that the genome lacked any of the well-known dye-decolorizing peroxidase or catalase-peroxidase that are commonly reported to be involved in lignin depolymerization by bacteria, indicating that strain S11Y has distinct sets of potential lignin depolymerization genes. The oxidative stress-related enzymes Cu/Zn type-superoxide dismutase (Sod2) and a heme-containing monofunctional catalase (Kat2) were identified in the genome sequences that are of interest. Their lignin-depolymerizing ability were evaluated by treating Alkali lignin (AL) with each enzyme and their degradation ability were evaluated using gel-permeation chromatography (GPC), ultrahigh-pressure liquid chromatography-mass spectrometry (UHPLC/MS), and gas chromatography-mass spectrometry (GC/MS), which successfully proved lignin depolymerizing ability. Successful evaluation of lignin depolymerizing enzymes can be applicable for lignin pretreatment process in green energy production and generation of valuable chemicals in bio-refinery.
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Affiliation(s)
- Fatimah Azizah Riyadi
- Department of Chemical Engineering, Faculty of Engineering, Universitas Indonesia
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia
| | - Nadia Farhana Azman
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia
| | - Fazrena Nadia Md Akhir
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia
| | - Nor'azizi Othman
- Department of Mechanical Precision Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia
| | - Hirofumi Hara
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo
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3
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Bugg TDH. The chemical logic of enzymatic lignin degradation. Chem Commun (Camb) 2024; 60:804-814. [PMID: 38165282 PMCID: PMC10795516 DOI: 10.1039/d3cc05298b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024]
Abstract
Lignin is an aromatic heteropolymer, found in plant cell walls as 20-30% of lignocellulose. It represents the most abundant source of renewable aromatic carbon in the biosphere, hence, if it could be depolymerised efficiently, then it would be a highly valuable source of renewable aromatic chemicals. However, lignin presents a number of difficulties for biocatalytic or chemocatalytic breakdown. Research over the last 10 years has led to the identification of new bacterial enzymes for lignin degradation, and the use of metabolic engineering to generate useful bioproducts from microbial lignin degradation. The aim of this article is to discuss the chemical mechanisms used by lignin-degrading enzymes and microbes to break down lignin, and to describe current methods for generating aromatic bioproducts from lignin using enzymes and engineered microbes.
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Affiliation(s)
- Timothy D H Bugg
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, UK.
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4
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Yang L, Wei J, Feng W. Co-immobilization of galactose oxidase, catalase, and Mn-superoxide dismutase for efficient conversion of 5-hydroxymethylfurfural to 2,5-diformylfuran in water. Colloids Surf B Biointerfaces 2023; 231:113541. [PMID: 37722253 DOI: 10.1016/j.colsurfb.2023.113541] [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: 07/01/2023] [Revised: 09/02/2023] [Accepted: 09/10/2023] [Indexed: 09/20/2023]
Abstract
The three enzymes galactose oxidase (GO), catalase (CAT), and Mn-superoxide dismutase (SOD) were simultaneously immobilized by coordinating to CuII in phosphate buffer saline. The biocatalyst GO&CAT&SOD@CuII was used for the conversion of 5-hydroxymethylfurfural (HMF). The immobilized GO catalyzes the oxidation of HMF to 2,5-diformylfuran (DFF), concomitantly the co-substrate O2 is reduced to hydrogen peroxide (H2O2). A portion of the byproduct H2O2 is broken down to O2 and H2O by the co-immobilized CAT, and the evolved O2 can be recycled and used as the co-substrate. A portion of the byproduct H2O2 is broken down to produce hydroxyl radicals •OH under the synergistic catalysis of the immobilized SOD and coordinated CuII, and the produced •OH can reactivate the immobilized galactose oxidase. Two aspects contribute to the high catalytic efficiency by GO&CAT&SOD@CuII: the reactivation of the immobilized galactose oxidase by producing •OH and the enrichment of the co-substate O2 by recycling the produced O2. For the conversion of 10 mM HMF, GO&CAT&SOD@CuII (with encapsulated GO 0.2 mg/mL) achieved 97% HMF conversion within 2 h reaction. In contrast, free galactose oxidase M3-5 variant (ACS Catalysis 2018, 8, 4025) (0.2 mg/mL) achieved 25.3% HMF conversion within 2 h reaction. All the reactions were carried out in pure water, not in PBS.
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Affiliation(s)
- Lu Yang
- Department of Biological Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Jiaxing Wei
- Department of Biological Engineering, Beijing University of Chemical Technology, Beijing, China
| | - Wei Feng
- Department of Biological Engineering, Beijing University of Chemical Technology, Beijing, China.
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Kariuki EG, Kibet C, Paredes JC, Mboowa G, Mwaura O, Njogu J, Masiga D, Bugg TDH, Tanga CM. Metatranscriptomic analysis of the gut microbiome of black soldier fly larvae reared on lignocellulose-rich fiber diets unveils key lignocellulolytic enzymes. Front Microbiol 2023; 14:1120224. [PMID: 37180276 PMCID: PMC10171111 DOI: 10.3389/fmicb.2023.1120224] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 04/03/2023] [Indexed: 05/16/2023] Open
Abstract
Recently, interest in the black soldier fly larvae (BSFL) gut microbiome has received increased attention primarily due to their role in waste bioconversion. However, there is a lack of information on the positive effect on the activities of the gut microbiomes and enzymes (CAZyme families) acting on lignocellulose. In this study, BSFL were subjected to lignocellulose-rich diets: chicken feed (CF), chicken manure (CM), brewers' spent grain (BSG), and water hyacinth (WH). The mRNA libraries were prepared, and RNA-Sequencing was conducted using the PCR-cDNA approach through the MinION sequencing platform. Our results demonstrated that BSFL reared on BSG and WH had the highest abundance of Bacteroides and Dysgonomonas. The presence of GH51 and GH43_16 enzyme families in the gut of BSFL with both α-L-arabinofuranosidases and exo-alpha-L-arabinofuranosidase 2 were common in the BSFL reared on the highly lignocellulosic WH and BSG diets. Gene clusters that encode hemicellulolytic arabinofuranosidases in the CAZy family GH51 were also identified. These findings provide novel insight into the shift of gut microbiomes and the potential role of BSFL in the bioconversion of various highly lignocellulosic diets to fermentable sugars for subsequent value-added products (bioethanol). Further research on the role of these enzymes to improve existing technologies and their biotechnological applications is crucial.
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Affiliation(s)
- Eric G. Kariuki
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
- Department of Immunology and Molecular Biology, Makerere University, Kampala, Uganda
| | - Caleb Kibet
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Juan C. Paredes
- Department of Immunology and Molecular Biology, Makerere University, Kampala, Uganda
| | - Gerald Mboowa
- Department of Immunology and Molecular Biology, Makerere University, Kampala, Uganda
| | - Oscar Mwaura
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - John Njogu
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Daniel Masiga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
| | - Timothy D. H. Bugg
- Department of Chemistry, School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Chrysantus M. Tanga
- International Centre of Insect Physiology and Ecology (icipe), Nairobi, Kenya
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Du B, Li W, Zhu H, Xu J, Wang Q, Shou X, Wang X, Zhou J. A functional lignin for heavy metal ions adsorption and wound care dressing. Int J Biol Macromol 2023; 239:124268. [PMID: 37003375 DOI: 10.1016/j.ijbiomac.2023.124268] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 03/15/2023] [Accepted: 03/27/2023] [Indexed: 04/03/2023]
Abstract
Recently, the application of lignin activation by demethylation to improve reactivity and enrich multiple functions has intensively attracted attention. However, it is still challenge up to now due to the low reactivity and complexity of lignin structure. Here, an effective demethylation way was explored by microwave-assisted method for substantially enhancing the hydroxyl (-OH) content and retaining the structure of lignin. Then, the optimum demethylated lignin was used to removal heavy metal ions and promote wound healing, respectively. In detail, for microwave-assisted demethylated poplar lignin (M-DPOL), the contents of phenolic (Ar-OH) and total hydroxyl (Tot-OH) groups reached the maximum for 60 min at 90 °C in DMF with 7.38 and 9.13 mmol/g, respectively. After demethylation, with this M-DPOL as lignin-based adsorbent, the maximum adsorption capacity (Qmax) for Pb2+ ions reached 104.16 mg/g. Based on the isotherm, kinetic and thermodynamic models analyses, the chemisorption occurred in monolayer on the surface of M-DPOL, and all adsorption processes were endothermic and spontaneous. Meanwhile, M-DPOL as a wound dressing had excellent antioxidant property, outstanding bactericidal activity and remarkable biocompatibility, suggesting that it did not interfere with cell proliferation. Besides, the wounded rats treated with M-DPOL significantly promoted its formation of re-epithelialization and wound healing of full-thickness skin defects. Overall, microwave-assisted method of demethylated lignin can offer great advantages for heavy metal ions removal and wound care dressing, which facilitates high value application of lignin.
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Affiliation(s)
- Boyu Du
- Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, Dalian Polytechnic University, Dalian, Liaoning 116034, China
| | - Wanjing Li
- Department of Cardiology, Shaanxi Province People's Hospital and The Third Affiliated Hospital Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710018, China
| | - Hongwei Zhu
- Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, Dalian Polytechnic University, Dalian, Liaoning 116034, China
| | - Jingyu Xu
- Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, Dalian Polytechnic University, Dalian, Liaoning 116034, China
| | - Qingyu Wang
- Institute for Catalysis (ICAT) and Graduate School of Chemical Sciences and Engineering, Hokkaido University, N21W10, Kita-ku, Sapporo 001-0021, Japan
| | - Xiling Shou
- Department of Cardiology, Shaanxi Province People's Hospital and The Third Affiliated Hospital Medical College of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710018, China.
| | - Xing Wang
- Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, Dalian Polytechnic University, Dalian, Liaoning 116034, China.
| | - Jinghui Zhou
- Liaoning Key Laboratory of Lignocellulose Chemistry and Biomaterials, Dalian Polytechnic University, Dalian, Liaoning 116034, China.
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Li J, Dong C, Sen B, Lai Q, Gong L, Wang G, Shao Z. Lignin-oxidizing and xylan-hydrolyzing Vibrio involved in the mineralization of plant detritus in the continental slope. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 854:158714. [PMID: 36113801 DOI: 10.1016/j.scitotenv.2022.158714] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 09/04/2022] [Accepted: 09/08/2022] [Indexed: 06/15/2023]
Abstract
A large amount of terrigenous organic matter (TOM) is constantly transported to the deep sea. However, relatively little is known about the microbial mineralization of TOM therein. Our recent in situ enrichment experiments revealed that Vibrio is especially enriched as one of the predominant taxa in the cultures amended with natural plant materials in the deep sea. Yet their role in the mineralization of plant-derived TOM in the deep sea remains largely unknown. Here we isolated Vibrio strains representing dominant members of the enrichments and verified their potential to degrade lignin and xylan. The isolated strains were closely related to Vibrio harveyi, V. alginolyticus, V. diabolicus, and V. parahaemolyticus. Extracellular enzyme assays, and genome and transcriptome analyses revealed diverse peroxidases, including lignin peroxidase (LiP), catalase-peroxidase (KatG), and decolorizing peroxidase (DyP), which played an important role in the depolymerization and oxidation of lignin. Superoxide dismutase was found to likely promote lignin oxidation by supplying H2O2 to LiP, DyP, and KatG. Interestingly, these deep-sea Vibrio strains could oxidize lignin and hydrolyze xylan not only through aerobic pathway, but also through anaerobic pathway. Genome analysis revealed multiple anaerobic respiratory mechanisms, including the reductions of nitrate, arsenate, tetrathionate, and dimethyl sulfoxide. The strains showed the potential to anaerobically reduce sulfite and metal oxides of iron and manganese, in contrast the non-deep-sea Vibrio strains were not retrieved of genes involved in reduction of metal oxides. This is the first report about the lignin oxidation mechanisms in Vibrio and their role in TOM mineralization in anoxic and oxic environments of the marginal sea.
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Affiliation(s)
- Jianyang Li
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300387, PR China; Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources of PR China, Xiamen 361005, PR China; State Key Laboratory Breeding Base of Marine Genetic Resources, Key Laboratory of Marine Genetic Resources of Fujian Province, Xiamen 361005, PR China; MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Chunming Dong
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources of PR China, Xiamen 361005, PR China; State Key Laboratory Breeding Base of Marine Genetic Resources, Key Laboratory of Marine Genetic Resources of Fujian Province, Xiamen 361005, PR China
| | - Biswarup Sen
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300387, PR China
| | - Qiliang Lai
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources of PR China, Xiamen 361005, PR China; State Key Laboratory Breeding Base of Marine Genetic Resources, Key Laboratory of Marine Genetic Resources of Fujian Province, Xiamen 361005, PR China
| | - Linfeng Gong
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources of PR China, Xiamen 361005, PR China; State Key Laboratory Breeding Base of Marine Genetic Resources, Key Laboratory of Marine Genetic Resources of Fujian Province, Xiamen 361005, PR China
| | - Guangyi Wang
- Center for Marine Environmental Ecology, School of Environmental Science and Engineering, Tianjin University, Tianjin 300387, PR China
| | - Zongze Shao
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources of PR China, Xiamen 361005, PR China; State Key Laboratory Breeding Base of Marine Genetic Resources, Key Laboratory of Marine Genetic Resources of Fujian Province, Xiamen 361005, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, PR China.
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Frequent Occurrence and Metabolic Versatility of Marinifilaceae Bacteria as Key Players in Organic Matter Mineralization in Global Deep Seas. mSystems 2022; 7:e0086422. [PMID: 36342154 PMCID: PMC9765461 DOI: 10.1128/msystems.00864-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Transfer of animal and plant detritus of both terrestrial and marine origins to the deep sea occurs on a global scale. Microorganisms play an important role in mineralizing them therein, but these are yet to be identified in situ. To observe key bacteria involved, we conducted long-term in situ incubation and found that members of the family Marinifilaceae (MF) occurred as some of the most predominant bacteria thriving on the new inputs of plant and animal biomasses in the deep sea in both marginal and oceanic areas. This taxon is diverse and ubiquitous in marine environments. A total of 11 MAGs belonging to MF were retrieved from metagenomic data and diverged into four subgroups in the phylogenomic tree. Based on metagenomic and metatranscriptomic analyses, we described the metabolic features and in situ metabolizing activities of different subgroups. The MF-2 subgroup, which dominates plant detritus-enriched cultures, specializes in polysaccharide degradation and lignin oxidation and has high transcriptional activities of related genes in situ. Intriguingly, members of this subgroup encode a nitrogen fixation pathway to compensate for the shortage of nitrogen sources inside the plant detritus. In contrast, other subgroups dominating the animal tissue-supported microbiomes are distinguished from MF-2 with regard to carbon and nitrogen metabolism and exhibit high transcriptional activity for proteolysis in situ. Despite these metabolic divergences of MF lineages, they show high in situ transcriptional activities for organic fermentation and anaerobic respiration (reductions of metal and/or dimethyl sulfoxide). These results highlight the role of previously unrecognized Marinifilaceae bacteria in organic matter mineralization in marine environments by coupling carbon and nitrogen cycling with metal and sulfur. IMPORTANCE Microbial mineralization of organic matter has a significant impact on the global biogeochemical cycle. This report confirms the role of Marinifilaceae in organic degradation in the oceans, with a contribution to ocean carbon cycling that has previously been underestimated. It was the dominant taxon thriving on plant and animal biomasses in our in situ incubator, as well as in whale falls and wood falls. At least 9 subgroups were revealed, and they were widely distributed in oceans globally but predominant in organic-matter-rich environments, with an average relative abundance of 8.3%. Different subgroups display a preference for the degradation of different macromolecules (polysaccharides, lignin, and protein) and adapt to their environments via special metabolic mechanisms.
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Preparation of activated lignin with high hydroxyl content using lewis acid as demethylation reagent. Int J Biol Macromol 2022; 222:2571-2580. [DOI: 10.1016/j.ijbiomac.2022.10.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 09/22/2022] [Accepted: 10/06/2022] [Indexed: 11/05/2022]
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Franco Cairo JPL, Mandelli F, Tramontina R, Cannella D, Paradisi A, Ciano L, Ferreira MR, Liberato MV, Brenelli LB, Gonçalves TA, Rodrigues GN, Alvarez TM, Mofatto LS, Carazzolle MF, Pradella JGC, Paes Leme AF, Costa-Leonardo AM, Oliveira-Neto M, Damasio A, Davies GJ, Felby C, Walton PH, Squina FM. Oxidative cleavage of polysaccharides by a termite-derived superoxide dismutase boosts the degradation of biomass by glycoside hydrolases. GREEN CHEMISTRY : AN INTERNATIONAL JOURNAL AND GREEN CHEMISTRY RESOURCE : GC 2022; 24:4845-4858. [PMID: 35813357 PMCID: PMC9208272 DOI: 10.1039/d1gc04519a] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 05/07/2022] [Indexed: 05/31/2023]
Abstract
Wood-feeding termites effectively degrade plant biomass through enzymatic degradation. Despite their high efficiencies, however, individual glycoside hydrolases isolated from termites and their symbionts exhibit anomalously low effectiveness in lignocellulose degradation, suggesting hereto unknown enzymatic activities in their digestome. Herein, we demonstrate that an ancient redox-active enzyme encoded by the lower termite Coptotermes gestroi, a Cu/Zn superoxide dismutase (CgSOD-1), plays a previously unknown role in plant biomass degradation. We show that CgSOD-1 transcripts and peptides are up-regulated in response to an increased level of lignocellulose recalcitrance and that CgSOD-1 localizes in the lumen of the fore- and midguts of C. gestroi together with termite main cellulase, CgEG-1-GH9. CgSOD-1 boosts the saccharification of polysaccharides by CgEG-1-GH9. We show that the boosting effect of CgSOD-1 involves an oxidative mechanism of action in which CgSOD-1 generates reactive oxygen species that subsequently cleave the polysaccharide. SOD-type enzymes constitute a new addition to the growing family of oxidases, ones which are up-regulated when exposed to recalcitrant polysaccharides, and that are used by Nature for biomass degradation.
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Affiliation(s)
- João Paulo L Franco Cairo
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP) Campinas São Paulo Brazil
- Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen Rolighedsvej 23 DK-1958 Frederiksberg C Denmark
- Department of Chemistry, University of York York YO10 5DD UK
| | - Fernanda Mandelli
- Brazilian Biorenewables National Laboratory, Brazilian Center for Research in Energy and Materials Campinas São Paulo Brazil
| | - Robson Tramontina
- Programa de Processos Tecnológicos e Ambientais da Universidade de Sorocaba (UNISO) Sorocaba SP Brazil
| | - David Cannella
- Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen Rolighedsvej 23 DK-1958 Frederiksberg C Denmark
| | | | - Luisa Ciano
- Department of Chemistry, University of York York YO10 5DD UK
| | - Marcel R Ferreira
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista, UNESP Botucatu São Paulo Brasil
| | - Marcelo V Liberato
- Programa de Processos Tecnológicos e Ambientais da Universidade de Sorocaba (UNISO) Sorocaba SP Brazil
| | - Lívia B Brenelli
- Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen Rolighedsvej 23 DK-1958 Frederiksberg C Denmark
- Brazilian Biorenewables National Laboratory, Brazilian Center for Research in Energy and Materials Campinas São Paulo Brazil
| | - Thiago A Gonçalves
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP) Campinas São Paulo Brazil
| | - Gisele N Rodrigues
- Brazilian Biorenewables National Laboratory, Brazilian Center for Research in Energy and Materials Campinas São Paulo Brazil
| | - Thabata M Alvarez
- Programa de Mestrado e Doutorado em Biotecnologia Industrial, Universidade Positivo Curitiba PR Brasil
| | - Luciana S Mofatto
- Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade de Campinas, UNICAMP Campinas São Paulo Brasil
| | - Marcelo F Carazzolle
- Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade de Campinas, UNICAMP Campinas São Paulo Brasil
| | - José G C Pradella
- Brazilian Biorenewables National Laboratory, Brazilian Center for Research in Energy and Materials Campinas São Paulo Brazil
| | - Adriana F Paes Leme
- Laboratório Nacional de Biociências (LNBio) do Centro Nacional de Pesquisa em Energia e Materiais (CNPEM) Campinas São Paulo Brasil
| | - Ana M Costa-Leonardo
- Laboratório de Cupins, Departamento de Biologia Geral e Aplicada, Instituto de Biociências, Universidade Estadual Paulista, UNESP Rio Claro São Paulo Brasil
| | - Mário Oliveira-Neto
- Departamento de Física e Biofísica, Instituto de Biociências, Universidade Estadual Paulista, UNESP Botucatu São Paulo Brasil
| | - André Damasio
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP) Campinas São Paulo Brazil
| | - Gideon J Davies
- Department of Chemistry, University of York York YO10 5DD UK
| | - Claus Felby
- Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen Rolighedsvej 23 DK-1958 Frederiksberg C Denmark
| | - Paul H Walton
- Department of Chemistry, University of York York YO10 5DD UK
| | - Fabio M Squina
- Programa de Processos Tecnológicos e Ambientais da Universidade de Sorocaba (UNISO) Sorocaba SP Brazil
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Liu H, Liu ZH, Zhang RK, Yuan JS, Li BZ, Yuan YJ. Bacterial conversion routes for lignin valorization. Biotechnol Adv 2022; 60:108000. [DOI: 10.1016/j.biotechadv.2022.108000] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 05/31/2022] [Accepted: 05/31/2022] [Indexed: 12/12/2022]
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Jiang X, Tian Z, Ji X, Ma H, Yang G, He M, Dai L, Xu T, Si C. Alkylation modification for lignin color reduction and molecular weight adjustment. Int J Biol Macromol 2022; 201:400-410. [PMID: 34995668 DOI: 10.1016/j.ijbiomac.2021.12.162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/21/2021] [Accepted: 12/25/2021] [Indexed: 01/04/2023]
Abstract
The application of industrial kraft lignin is limited by its low molecular weight, dark color, and low solubility. In this work, an efficient crosslinking reaction with N,N-Dimethylformamide (DMF) and 1,6-dibromohexane was proposed for adjusting the molecular weight and color of lignin. The chemical structure of alkylation lignin was systematically investigated by gel permeation chromatography (GPC), ultraviolet spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and 2D heteronuclear single quantum correlation nuclear magnetic resonance (HSQC NMR) spectra. After the alkylation modification, the molecular weights of the lignin were increased to 1643%. The resinol (β-β), β-aryl ether (β-O-4), and phenylcoumaran (β-5) linkages were still the main types of the linkages. The formation of β-β linkage would be inhibited at high temperatures. The color reduction of lignin can be attributed to the low content of chromophores and low packing density. This alkylation lignin will be a new and general approach for developing molecular weight-controlled and light-colored lignins, which can find more applications in cosmetics, packing, and other fields.
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Affiliation(s)
- Xiao Jiang
- State Key Laboratory of Bio-based Materials and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan 250353, China; Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
| | - Zhongjian Tian
- State Key Laboratory of Bio-based Materials and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan 250353, China; Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.
| | - Xingxiang Ji
- State Key Laboratory of Bio-based Materials and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan 250353, China; Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.
| | - Hao Ma
- State Key Laboratory of Bio-based Materials and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan 250353, China
| | - Guihua Yang
- State Key Laboratory of Bio-based Materials and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan 250353, China
| | - Ming He
- State Key Laboratory of Bio-based Materials and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan 250353, China
| | - Lin Dai
- State Key Laboratory of Bio-based Materials and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan 250353, China; Tianjin Key Laboratory of Pulp and Paper, College of Light Industry and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Ting Xu
- Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China; Tianjin Key Laboratory of Pulp and Paper, College of Light Industry and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Chuanling Si
- State Key Laboratory of Bio-based Materials and Green Papermaking, Qilu University of Technology (Shandong Academy of Sciences), 3501 Daxue Road, Jinan 250353, China; Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China; Tianjin Key Laboratory of Pulp and Paper, College of Light Industry and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China.
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The Termite Fungal Cultivar Termitomyces Combines Diverse Enzymes and Oxidative Reactions for Plant Biomass Conversion. mBio 2021; 12:e0355120. [PMID: 34126770 PMCID: PMC8262964 DOI: 10.1128/mbio.03551-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Macrotermitine termites have domesticated fungi in the genus Termitomyces as their primary food source using predigested plant biomass. To access the full nutritional value of lignin-enriched plant biomass, the termite-fungus symbiosis requires the depolymerization of this complex phenolic polymer. While most previous work suggests that lignocellulose degradation is accomplished predominantly by the fungal cultivar, our current understanding of the underlying biomolecular mechanisms remains rudimentary. Here, we provide conclusive omics and activity-based evidence that Termitomyces employs not only a broad array of carbohydrate-active enzymes (CAZymes) but also a restricted set of oxidizing enzymes (manganese peroxidase, dye decolorization peroxidase, an unspecific peroxygenase, laccases, and aryl-alcohol oxidases) and Fenton chemistry for biomass degradation. We propose for the first time that Termitomyces induces hydroquinone-mediated Fenton chemistry (Fe2+ + H2O2 + H+ → Fe3+ + •OH + H2O) using a herein newly described 2-methoxy-1,4-dihydroxybenzene (2-MH2Q, compound 19)-based electron shuttle system to complement the enzymatic degradation pathways. This study provides a comprehensive depiction of how efficient biomass degradation by means of this ancient insect’s agricultural symbiosis is accomplished.
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Venkatesagowda B, Dekker RFH. Microbial demethylation of lignin: Evidence of enzymes participating in the removal of methyl/methoxyl groups. Enzyme Microb Technol 2021; 147:109780. [PMID: 33992403 DOI: 10.1016/j.enzmictec.2021.109780] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 02/27/2021] [Accepted: 03/11/2021] [Indexed: 11/30/2022]
Abstract
Lignin is an abundant natural plant aromatic biopolymer containing various functional groups that can be exploited for activating lignin for potential commercial applications. Applications are hindered due to the presence of a high content of methyl/methoxyl groups that affects reactiveness. Various chemical and enzymatic approaches have been investigated to increase the functionality in transforming lignin. Among these is demethylation/demethoxylation, which increases the potential numbers of vicinal hydroxyl groups for applications as phenol-formaldehyde resins. Although the chemical route to lignin demethylation is well-studied, the biological route is still poorly explored. Bacteria and fungi have the ability to demethylate lignin and lignin-related compounds. Considering that appropriate microorganisms possess the biochemical machinery to demethylate lignin by cleaving O-methyl groups liberating methanol, and modify lignin by increasing the vicinal diol content that allows lignin to substitute for phenol in organic polymer syntheses. Certain bacteria through the actions of specific O-demethylases can modify various lignin-related compounds generating vicinal diols and liberating methanol or formaldehyde as end-products. The enzymes include: cytochrome P450-aryl-O-demethylase, monooxygenase, veratrate 3-O-demethylase, DDVA O-demethylase (LigX; lignin-related biphenyl 5,5'-dehydrodivanillate (DDVA)), vanillate O-demethylase, syringate O-demethylase, and tetrahydrofolate-dependent-O-demethylase. Although, the fungal counterparts have not been investigated in depth as in bacteria, O-demethylases, nevertheless, have been reported in demethylating various lignin substrates providing evidence of a fungal enzyme system. Few fungi appear to have the ability to secrete O-demethylases. The fungi can mediate lignin demethylation enzymatically (laccase, lignin peroxidase, manganese peroxidase, O-demethylase), or non-enzymatically in brown-rot fungi through the Fenton reaction. This review discusses details on the aspects of microbial (bacterial and fungal) demethylation of lignins and lignin-model compounds and provides evidence of enzymes identified as specific O-demethylases involved in demethylation.
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Affiliation(s)
- Balaji Venkatesagowda
- Biorefining Research Institute, Lakehead University, Thunder Bay, Ontario, P7B 5E1, Canada.
| | - Robert F H Dekker
- Biorefining Research Institute, Lakehead University, Thunder Bay, Ontario, P7B 5E1, Canada; Universidade Tecnológica Federal do Paraná, Programa de Pós-Graduação em Engenharia Ambiental, Câmpus Londrina, CEP: 86036-370, Londrina, PR, Brazil.
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15
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Comparing Ligninolytic Capabilities of Bacterial and Fungal Dye-Decolorizing Peroxidases and Class-II Peroxidase-Catalases. Int J Mol Sci 2021; 22:ijms22052629. [PMID: 33807844 PMCID: PMC7961821 DOI: 10.3390/ijms22052629] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 02/27/2021] [Accepted: 02/28/2021] [Indexed: 11/17/2022] Open
Abstract
We aim to clarify the ligninolytic capabilities of dye-decolorizing peroxidases (DyPs) from bacteria and fungi, compared to fungal lignin peroxidase (LiP) and versatile peroxidase (VP). With this purpose, DyPs from Amycolatopsis sp., Thermomonospora curvata, and Auricularia auricula-judae, VP from Pleurotus eryngii, and LiP from Phanerochaete chrysosporium were produced, and their kinetic constants and reduction potentials determined. Sharp differences were found in the oxidation of nonphenolic simple (veratryl alcohol, VA) and dimeric (veratrylglycerol-β- guaiacyl ether, VGE) lignin model compounds, with LiP showing the highest catalytic efficiencies (around 15 and 200 s−1·mM−1 for VGE and VA, respectively), while the efficiency of the A. auricula-judae DyP was 1–3 orders of magnitude lower, and no activity was detected with the bacterial DyPs. VP and LiP also showed the highest reduction potential (1.28–1.33 V) in the rate-limiting step of the catalytic cycle (i.e., compound-II reduction to resting enzyme), estimated by stopped-flow measurements at the equilibrium, while the T. curvata DyP showed the lowest value (1.23 V). We conclude that, when using realistic enzyme doses, only fungal LiP and VP, and in much lower extent fungal DyP, oxidize nonphenolic aromatics and, therefore, have the capability to act on the main moiety of the native lignin macromolecule.
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Cattò C, Sanmartín P, Gulotta D, Troiano F, Cappitelli F. Bioremoval of graffiti using novel commercial strains of bacteria. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 756:144075. [PMID: 33280882 DOI: 10.1016/j.scitotenv.2020.144075] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 11/18/2020] [Accepted: 11/21/2020] [Indexed: 06/12/2023]
Abstract
Previous studies have provided evidence that bioremediation deals a novel approach to graffiti removal, thereby overcoming well-known limitations of current cleaning methods. In the present study eight bacteria aerobic, mesophilic and culturable from the American ATCC and the German DSMZ collections of microorganisms, some isolated from car paint waste, colored deposits in a pulp dryer and wastewater from dye works, were tested in the removal of silver and black graffiti spray paints using immersion strategies with glass slides. Absorbance at 600 nm and live/dead assays were performed to estimate bacterial density and activity in all samples. Also, pH and dissolved organic carbon (DOC) and inorganic carbon (DIC) measurements in the liquid media were made, as well as, thickness, colorimetric and infrared (FTIR) spectroscopy measurements in graffiti paint layers were used to evaluate the presence of the selected bacteria in the samples and the graffiti bioremoval capacity of bacteria. Data demonstrated that of the eight bacteria studied, Enterobacter aerogenes, Comamonas sp. and a mixture of Bacillus sp., Delftia lacustris, Sphingobacterium caeni, and Ochrobactrum anthropi were the most promising for bioremoval of graffiti. According to significant changes in FTIR spectra, indicating an alteration of the paint polymeric structure, coupled with the presence of a consistent quantity of live bacteria in the medium as well as a significant increase of DIC (a measure of metabolic activity) and a change in paint color.
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Affiliation(s)
- Cristina Cattò
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy.
| | - Patricia Sanmartín
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy; Departamento de Edafoloxía e Química Agrícola, Facultade de Farmacia, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
| | - Davide Gulotta
- Getty Conservation Institute, Science Department, 1200 Getty Center Drive, Los Angeles, CA 90049, USA.
| | - Federica Troiano
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy.
| | - Francesca Cappitelli
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy.
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Díaz-García L, Bugg TDH, Jiménez DJ. Exploring the Lignin Catabolism Potential of Soil-Derived Lignocellulolytic Microbial Consortia by a Gene-Centric Metagenomic Approach. MICROBIAL ECOLOGY 2020; 80:885-896. [PMID: 32572536 DOI: 10.1007/s00248-020-01546-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 06/15/2020] [Indexed: 05/25/2023]
Abstract
An exploration of the ligninolytic potential of lignocellulolytic microbial consortia can improve our understanding of the eco-enzymology of lignin conversion in nature. In this study, we aimed to detect enriched lignin-transforming enzymes on metagenomes from three soil-derived microbial consortia that were cultivated on "pre-digested" plant biomass (wheat straw, WS1-M; switchgrass, SG-M; and corn stover, CS-M). Of 60 selected enzyme-encoding genes putatively involved in lignin catabolism, 20 genes were significantly abundant in WS1-M, CS-M, and/or SG-M consortia compared with the initial forest soil inoculum metagenome (FS1). These genes could be involved in lignin oxidation (e.g., superoxide dismutases), oxidative stress responses (e.g., catalase/peroxidases), generation of protocatechuate (e.g., vanAB genes), catabolism of gentisate, catechol and 3-phenylpropionic acid (e.g., gentisate 1,2-dioxygenases, muconate cycloisomerases, and hcaAB genes), the beta-ketoadipate pathway (e.g., pcaIJ genes), and tolerance to lignocellulose-derived inhibitors (e.g., thymidylate synthases). The taxonomic affiliation of 22 selected lignin-transforming enzymes from WS1-M and CS-M consortia metagenomes revealed that Pseudomonadaceae, Alcaligenaceae, Sphingomonadaceae, Caulobacteraceae, Comamonadaceae, and Xanthomonadaceae are the key bacterial families in the catabolism of lignin. A predictive "model" was sketched out, where each microbial population has the potential to metabolize an array of aromatic compounds through different pathways, suggesting that lignin catabolism can follow a "task division" strategy. Here, we have established an association between functions and taxonomy, allowing a better understanding of lignin transformations in soil-derived lignocellulolytic microbial consortia, and pinpointing some bacterial taxa and catabolic genes as ligninolytic trait-markers.
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Affiliation(s)
- Laura Díaz-García
- Microbiomes and Bioenergy Research Group, Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia
| | | | - Diego Javier Jiménez
- Microbiomes and Bioenergy Research Group, Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia.
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Tramontina R, Brenelli LB, Sodré V, Franco Cairo JP, Travália BM, Egawa VY, Goldbeck R, Squina FM. Enzymatic removal of inhibitory compounds from lignocellulosic hydrolysates for biomass to bioproducts applications. World J Microbiol Biotechnol 2020; 36:166. [PMID: 33000321 DOI: 10.1007/s11274-020-02942-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 09/25/2020] [Indexed: 01/04/2023]
Abstract
The physicochemical pretreatment is an important step to reduce biomass recalcitrance and facilitate further processing of plant lignocellulose into bioproducts. This process results in soluble and insoluble biomass fractions, and both may contain by-products that inhibit enzymatic biocatalysts and microbial fermentation. These fermentation inhibitory compounds (ICs) are produced during the degradation of lignin and sugars, resulting in phenolic and furanic compounds, and carboxylic acids. Therefore, detoxification steps may be required to improve lignocellulose conversion by microoganisms. Several physical and chemical methods, such as neutralization, use of activated charcoal and organic solvents, have been developed and recommended for removal of ICs. However, biological processes, especially enzyme-based, have been shown to efficiently remove ICs with the advantage of minimizing environmental issues since they are biogenic catalysts and used in low quantities. This review focuses on describing several enzymatic approaches to promote detoxification of lignocellulosic hydrolysates and improve the performance of microbial fermentation for the generation of bioproducts. Novel strategies using classical carbohydrate active enzymes (CAZymes), such as laccases (AA1) and peroxidases (AA2), as well as more advanced strategies using prooxidant, antioxidant and detoxification enzymes (dubbed as PADs), i.e. superoxide dismutases, are discussed as perspectives in the field.
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Affiliation(s)
- Robson Tramontina
- Programa de Pós-Graduação em Biociências e Tecnologia de Produtos Bioativos (BTPB), Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil
- School of Food Engineering, State University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Lívia Beatriz Brenelli
- Interdisciplinary Center of Energy Planning (NIPE), State University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Victoria Sodré
- Programa de Processos Tecnológicos e Ambientais, Universidade de Sorocaba (UNISO), Sorocaba, São Paulo, Brazil
- Programa de Pós-Graduação em Biologia Funcional e Molecular (BFM), Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - João Paulo Franco Cairo
- Programa de Processos Tecnológicos e Ambientais, Universidade de Sorocaba (UNISO), Sorocaba, São Paulo, Brazil
| | | | - Viviane Yoshimi Egawa
- School of Agriculture, São Paulo State University (UNESP), Botucatu, São Paulo, Brazil
| | - Rosana Goldbeck
- School of Food Engineering, State University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Fabio Marcio Squina
- Programa de Processos Tecnológicos e Ambientais, Universidade de Sorocaba (UNISO), Sorocaba, São Paulo, Brazil.
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Bacterial enzymes for lignin depolymerisation: new biocatalysts for generation of renewable chemicals from biomass. Curr Opin Chem Biol 2020; 55:26-33. [PMID: 31918394 DOI: 10.1016/j.cbpa.2019.11.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 10/17/2019] [Accepted: 11/19/2019] [Indexed: 11/20/2022]
Abstract
The conversion of polymeric lignin from plant biomass into renewable chemicals is an important unsolved problem in the biorefinery concept. This article summarises recent developments in the discovery of bacterial enzymes for lignin degradation, our current understanding of their molecular mechanism of action, and their use to convert lignin or lignocellulose into aromatic chemicals. The review also discusses the recent developments in screening of metagenomic libraries for new biocatalysts, and the use of protein engineering to enhance lignin degradation activity.
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Tramontina R, Brenelli LB, Sousa A, Alves R, Zetty Arenas AM, Nascimento VM, Rabelo SC, Freitas S, Ruller R, Squina FM. Designing a cocktail containing redox enzymes to improve hemicellulosic hydrolysate fermentability by microorganisms. Enzyme Microb Technol 2019; 135:109490. [PMID: 32146936 DOI: 10.1016/j.enzmictec.2019.109490] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 11/07/2019] [Accepted: 12/09/2019] [Indexed: 12/22/2022]
Abstract
Bioproducts production using monomeric sugars derived from lignocellulosic biomass presents several challenges, such as to require a physicochemical pretreatment to improve its conversion yields. Hydrothermal lignocellulose pretreatment has several advantages and results in solid and liquid streams. The former is called hemicellulosic hydrolysate (HH), which contains inhibitory phenolic compounds and sugar degradation products that hinder microbial fermentation products from pentose sugars. Here, we developed and applied a novel enzyme process to detoxify HH. Initially, the design of experiments with different redox activities enzymes was carried out. The enzyme mixture containing the peroxidase (from Armoracia rusticana) together with superoxide dismutase (from Coptotermes gestroi) are the most effective to detoxify HH derived from sugarcane bagasse. Butanol fermentation by the bacteria Clostridium saccharoperbutylacetonicum and ethanol production by the yeast Scheffersomyces stipitis increased by 24.0× and 2.4×, respectively, relative to the untreated hemicellulosic hydrolysates. Detoxified HH was analyzed by chromatographic and spectrometric methods elucidating the mechanisms of phenolic compound modifications by enzymatic treatment. The enzyme mixture degraded and reduced the hydroxyphenyl- and feruloyl-derived units and polymerized the lignin fragments. This strategy uses biocatalysts under environmentally friendly conditions and could be applied in the fuel, food, and chemical industries.
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Affiliation(s)
- Robson Tramontina
- Laboratório Nacional de Biorrenováveis (LNBR) Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil; Programa em Biociências e Tecnologia de Produtos Bioativos (BTPB), Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil
| | - Lívia Beatriz Brenelli
- Laboratório Nacional de Biorrenováveis (LNBR) Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil
| | - Amanda Sousa
- Laboratório Nacional de Biorrenováveis (LNBR) Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil
| | | | - Ana Maria Zetty Arenas
- Laboratório Nacional de Biorrenováveis (LNBR) Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil; Programa em Bioenergia, Faculdade de Engenharia de Alimentos, Universidade Estadual de Campinas, (UNICAMP), Campinas, SP, Brazil
| | - Viviane Marcos Nascimento
- Laboratório Nacional de Biorrenováveis (LNBR) Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil
| | - Sarita Cândida Rabelo
- Departamento de Bioprocessos e Biotecnologia, Faculdade de Ciências Agronômicas, Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Botucatu, São Paulo, Brazil
| | - Sindélia Freitas
- Laboratório Nacional de Biorrenováveis (LNBR) Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas, SP, Brazil; Programa em Bioenergia, Faculdade de Engenharia de Alimentos, Universidade Estadual de Campinas, (UNICAMP), Campinas, SP, Brazil; Faculdade de Engenharia Química (FEQ), Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil
| | - Roberto Ruller
- Laboratório de Bioquimica Geral e de Microorganismos, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, MS, Brazil; Instituto de Biociências, Letras e Ciências Exatas (IBILCE), Universidade Estadual Paulista, São José do Rio Preto, SP, Brazil
| | - Fabio Marcio Squina
- Programa em Processos Tecnológicos e Ambientais, Universidade de Sorocaba (UNISO), Sorocaba, SP, Brazil.
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Morya R, Kumar M, Singh SS, Thakur IS. Genomic analysis of Burkholderia sp. ISTR5 for biofunneling of lignin-derived compounds. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:277. [PMID: 31788027 PMCID: PMC6880542 DOI: 10.1186/s13068-019-1606-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 10/29/2019] [Indexed: 05/25/2023]
Abstract
BACKGROUND Lignin is the second most abundant natural polymer on earth. Industries using lignocellulosic biomass as feedstock generate a considerable amount of lignin as a byproduct with minimal usage. For a sustainable biorefinery, the lignin must be utilized in improved ways. Lignin is recalcitrant to degradation due to the complex and heterogeneous structure. The depolymerization of lignin and its conversion into specific product stream are the major challenges associated with lignin valorization. The blend of oligomeric, dimeric and monomeric lignin-derived compounds (LDCs) generated during depolymerization can be utilized by microbes for production of bioproducts. RESULTS In the present study, a novel bacterium Burkholderia sp. strain ISTR5 (R5), a proteobacteria belonging to class betaproteobacteria, order Burkholderiales and family Burkholderiaceae, was isolated and characterized for the degradation of LDCs. R5 strain was cultured on 12 LDCs in mineral salt medium (MSM) supplemented with individual compounds such as syringic acid, p-coumaric acid, ferulic acid, vanillin, vanillic acid, guaiacol, 4-hydroxybenzoic acid, gallic acid, benzoic acid, syringaldehyde, veratryl alcohol and catechol. R5 was able to grow and utilize all the selected LDCs. The degradation of selected LDCs was monitored by bacterial growth, total organic carbon (TOC) removal and UV-Vis absorption spectra in scan mode. TOC reduction shown in the sample contains syringic acid 80.7%, ferulic acid 84.1%, p-coumaric acid 85.9% and benzoic acid 83.2%. In UV-Vis absorption spectral scan, most of the lignin-associated peaks were found at or near 280 nm wavelength in the obtained absorption spectra. Enzyme assay for the ligninolytic enzymes was also performed, and it was observed that lignin peroxidase and laccase were predominantly expressed. Furthermore, the GC-MS analysis of LDCs was performed to identify the degradation intermediates from these compounds. The genomic analysis showed the robustness of this strain and identified various candidate genes responsible for the degradation of aromatic or lignin derivatives, detoxification mechanism, oxidative stress response and fatty acid synthesis. The presence of peroxidases (13%), laccases (4%), monooxygenases (23%), dioxygenase (44%), NADPH: quinone oxidoreductases (16%) and many other related enzymes supported the degradation of LDCs. CONCLUSION Numerous pathway intermediates were observed during experiment. Vanillin was found during growth on syringic acid, ferulic acid and p-coumaric acid. Some other intermediates like catechol, acetovanillone, syringaldehyde and 3,4-dihydroxybenzaldehyde from the recognized bacterial metabolic pathways existed during growth on the LDCs. The ortho- and meta cleavage pathway enzymes, such as the catechol-1,2-dioxygenase, protocatechuate 3,4-dioxygenase, catechol-2,3-dioxygenase and toluene-2,3-dioxygenase, were observed in the genome. In addition to the common aromatic degradation pathways, presence of the epoxyqueuosine reductase, 1,2-epoxyphenylacetyl-CoA isomerase in the genome advocates that this strain may follow the epoxy Coenzyme A thioester pathway for degradation.
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Affiliation(s)
- Raj Morya
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Madan Kumar
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Shashi Shekhar Singh
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
| | - Indu Shekhar Thakur
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
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22
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Venkatesagowda B. Enzymatic demethylation of lignin for potential biobased polymer applications. FUNGAL BIOL REV 2019. [DOI: 10.1016/j.fbr.2019.06.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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