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Kracher D, Lanzmaier T, Carneiro LV. Active roles of lytic polysaccharide monooxygenases in human pathogenicity. BIOCHIMICA ET BIOPHYSICA ACTA. PROTEINS AND PROTEOMICS 2024; 1872:141012. [PMID: 38492831 DOI: 10.1016/j.bbapap.2024.141012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/22/2024] [Accepted: 03/11/2024] [Indexed: 03/18/2024]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are redox enzymes widely studied for their involvement in microbial and fungal biomass degradation. The catalytic versatility of these enzymes is demonstrated by the recent discovery of LPMOs in arthropods, viruses, insects and ferns, where they fulfill diverse functions beyond biomass conversion. This mini-review puts a spotlight on a recently recognized aspect of LPMOs: their role in infectious processes in human pathogens. It discusses the occurrence and potential biological mechanisms of LPMOs associated with human pathogens and provides an outlook on future avenues in this emerging and exciting research field.
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Affiliation(s)
- Daniel Kracher
- Institute of Molecular Biotechnology, Graz University of Technology, Petersgasse 14, 8010 Graz, Austria; BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria.
| | - Tina Lanzmaier
- Institute of Molecular Biotechnology, Graz University of Technology, Petersgasse 14, 8010 Graz, Austria; BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria
| | - Leonor Vieira Carneiro
- Institute of Molecular Biotechnology, Graz University of Technology, Petersgasse 14, 8010 Graz, Austria; BioTechMed-Graz, Mozartgasse 12/II, 8010 Graz, Austria
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2
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Isaksen I, Jana S, Payne CM, Bissaro B, Røhr ÅK. The rotamer of the second-sphere histidine in AA9 lytic polysaccharide monooxygenase is pH dependent. Biophys J 2024; 123:1139-1151. [PMID: 38571309 PMCID: PMC11079946 DOI: 10.1016/j.bpj.2024.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 03/10/2024] [Accepted: 04/01/2024] [Indexed: 04/05/2024] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) catalyze a reaction that is crucial for the biological decomposition of various biopolymers and for the industrial conversion of plant biomass. Despite the importance of LPMOs, the exact molecular-level nature of the reaction mechanism is still debated today. Here, we investigated the pH-dependent conformation of a second-sphere histidine (His) that we call the stacking histidine, which is conserved in fungal AA9 LPMOs and is speculated to assist catalysis in several of the LPMO reaction pathways. Using constant-pH and accelerated molecular dynamics simulations, we monitored the dynamics of the stacking His in different protonation states for both the resting Cu(II) and active Cu(I) forms of two fungal LPMOs. Consistent with experimental crystallographic and neutron diffraction data, our calculations suggest that the side chain of the protonated and positively charged form is rotated out of the active site toward the solvent. Importantly, only one of the possible neutral states of histidine (HIE state) is observed in the stacking orientation at neutral pH or when bound to cellulose. Our data predict that, in solution, the stacking His may act as a stabilizer (via hydrogen bonding) of the Cu(II)-superoxo complex after the LPMO-Cu(I) has reacted with O2 in solution, which, in fine, leads to H2O2 formation. Also, our data indicate that the HIE-stacking His is a poor acid/base catalyst when bound to the substrate and, in agreement with the literature, may play an important stabilizing role (via hydrogen bonding) during the peroxygenase catalysis. Our study reveals the pH titration midpoint values of the pH-dependent orientation of the stacking His should be considered when modeling and interpreting LPMO reactions, whether it be for classical LPMO kinetics or in industry-oriented enzymatic cocktails, and for understanding LPMO behavior in slightly acidic natural processes such as fungal wood decay.
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Affiliation(s)
- Ingvild Isaksen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Suvamay Jana
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky
| | - Christina M Payne
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky
| | - Bastien Bissaro
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway; INRAE, Aix Marseille University, UMR1163 Biodiversité et Biotechnologie Fongiques, Marseille, France.
| | - Åsmund K Røhr
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway.
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3
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Decembrino D, Cannella D. The thin line between monooxygenases and peroxygenases. P450s, UPOs, MMOs, and LPMOs: A brick to bridge fields of expertise. Biotechnol Adv 2024; 72:108321. [PMID: 38336187 DOI: 10.1016/j.biotechadv.2024.108321] [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: 10/31/2023] [Revised: 02/04/2024] [Accepted: 02/06/2024] [Indexed: 02/12/2024]
Abstract
Many scientific fields, although driven by similar purposes and dealing with similar technologies, often appear so isolated and far from each other that even the vocabularies to describe the very same phenomenon might differ. Concerning the vast field of biocatalysis, a special role is played by those redox enzymes that employ oxygen-based chemistry to unlock transformations otherwise possible only with metal-based catalysts. As such, greener chemical synthesis methods and environmentally-driven biotechnological approaches were enabled over the last decades by the use of several enzymes and ultimately resulted in the first industrial applications. Among what can be called today the environmental biorefinery sector, biomass transformation, greenhouse gas reduction, bio-gas/fuels production, bioremediation, as well as bulk or fine chemicals and even pharmaceuticals manufacturing are all examples of fields in which successful prototypes have been demonstrated employing redox enzymes. In this review we decided to focus on the most prominent enzymes (MMOs, LPMO, P450 and UPO) capable of overcoming the ∼100 kcal mol-1 barrier of inactivated CH bonds for the oxyfunctionalization of organic compounds. Harnessing the enormous potential that lies within these enzymes is of extreme value to develop sustainable industrial schemes and it is still deeply coveted by many within the aforementioned fields of application. Hence, the ambitious scope of this account is to bridge the current cutting-edge knowledge gathered upon each enzyme. By creating a broad comparison, scientists belonging to the different fields may find inspiration and might overcome obstacles already solved by the others. This work is organised in three major parts: a first section will be serving as an introduction to each one of the enzymes regarding their structural and activity diversity, whereas a second one will be encompassing the mechanistic aspects of their catalysis. In this regard, the machineries that lead to analogous catalytic outcomes are depicted, highlighting the major differences and similarities. Finally, a third section will be focusing on the elements that allow the oxyfunctionalization chemistry to occur by delivering redox equivalents to the enzyme by the action of diverse redox partners. Redox partners are often overlooked in comparison to the catalytic counterparts, yet they represent fundamental elements to better understand and further develop practical applications based on mono- and peroxygenases.
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Affiliation(s)
- Davide Decembrino
- Photobiocatalysis Unit - Crop Production and Biostimulation Lab (CPBL), and Biomass Transformation Lab (BTL), École Interfacultaire de Bioingénieurs, Université Libre de Bruxelles, Belgium.
| | - David Cannella
- Photobiocatalysis Unit - Crop Production and Biostimulation Lab (CPBL), and Biomass Transformation Lab (BTL), École Interfacultaire de Bioingénieurs, Université Libre de Bruxelles, Belgium.
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4
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Wieduwilt EK, Lo Leggio L, Hedegård ED. A frontier-orbital view of the initial steps of lytic polysaccharide monooxygenase reactions. Dalton Trans 2024; 53:5796-5807. [PMID: 38445349 DOI: 10.1039/d3dt04275h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are copper enzymes that oxidatively cleave the strong C-H bonds in recalcitrant polysaccharide substrates, thereby playing a crucial role in biomass degradation. Recently, LPMOs have also been shown to be important for several pathogens. It is well established that the Cu(II) resting state of LPMOs is inactive, and the electronic structure of the active site needs to be altered to transform the enzyme into an active form. Whether this transformation occurs due to substrate binding or due to a unique priming reduction has remained speculative. Starting from four different crystal structures of the LPMO LsAA9A with well-defined oxidation states, we use a frontier molecular orbital approach to elucidate the initial steps of the LPMO reaction. We give an explanation for the requirement of the unique priming reduction and analyse electronic structure changes upon substrate binding. We further investigate how the presence of the substrate could facilitate an electron transfer from the copper active site to an H2O2 co-substrate. Our findings could help to control experimental LPMO reactions.
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Affiliation(s)
- Erna Katharina Wieduwilt
- Department of Physics, Chemistry, and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark.
| | - Leila Lo Leggio
- Department of Chemistry, University of Copenhagen, 2100 Copenhagen, Denmark
| | - Erik Donovan Hedegård
- Department of Physics, Chemistry, and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark.
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5
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Hu Y, Lin Y, Craig SL. Mechanically Triggered Polymer Deconstruction through Mechanoacid Generation and Catalytic Enol Ether Hydrolysis. J Am Chem Soc 2024; 146:2876-2881. [PMID: 38265762 DOI: 10.1021/jacs.3c10153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Polymers that amplify a transient external stimulus into changes in their morphology, physical state, or properties continue to be desirable targets for a range of applications. Here, we report a polymer comprising an acid-sensitive, hydrolytically unstable enol ether backbone onto which is embedded gem-dichlorocyclopropane (gDCC) mechanophores through a single postsynthetic modification. The gDCC mechanophore releases HCl in response to large forces of tension along the polymer backbone, and the acid subsequently catalyzes polymer deconstruction at the enol ether sites. Pulsed sonication of a 61 kDa PDHF with 77% gDCC on the backbone in THF with 100 mM H2O for 10 min triggers the subsequent degradation of the polymer to a final molecular weight of less than 3 kDa after 24 h of standing, whereas controls lacking either the gDCC or the enol ether reach final molecular weights of 38 and 27 kDa, respectively. The process of sonication, along with the presence of water and the existence of gDCC on the backbone, significantly accelerates the rate of polymer chain deconstruction. Both acid generation and the resulting triggered polymer deconstruction are translated to bulk, cross-linked polymer networks. Networks formed via thiol-ene cross-linking and subjected to unconstrained quasi-static uniaxial compression dissolve on time scales that are at least 3 times faster than controls where the mechanophore is not covalently coupled to the network. We anticipate that this concept can be extended to other acid-sensitive polymer networks for the stress-responsive deconstruction of gels and solvent-free elastomers.
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Affiliation(s)
- Yixin Hu
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Yangju Lin
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Stephen L Craig
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
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6
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Munzone A, Eijsink VGH, Berrin JG, Bissaro B. Expanding the catalytic landscape of metalloenzymes with lytic polysaccharide monooxygenases. Nat Rev Chem 2024; 8:106-119. [PMID: 38200220 DOI: 10.1038/s41570-023-00565-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/20/2023] [Indexed: 01/12/2024]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) have an essential role in global carbon cycle, industrial biomass processing and microbial pathogenicity by catalysing the oxidative cleavage of recalcitrant polysaccharides. Despite initially being considered monooxygenases, experimental and theoretical studies show that LPMOs are essentially peroxygenases, using a single copper ion and H2O2 for C-H bond oxygenation. Here, we examine LPMO catalysis, emphasizing key studies that have shaped our comprehension of their function, and address side and competing reactions that have partially obscured our understanding. Then, we compare this novel copper-peroxygenase reaction with reactions catalysed by haem iron enzymes, highlighting the different chemistries at play. We conclude by addressing some open questions surrounding LPMO catalysis, including the importance of peroxygenase and monooxygenase reactions in biological contexts, how LPMOs modulate copper site reactivity and potential protective mechanisms against oxidative damage.
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Affiliation(s)
- Alessia Munzone
- UMR1163 Biodiversité et Biotechnologie Fongiques, INRAE, Aix Marseille University, Marseille, France
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology, and Food Science, The Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Jean-Guy Berrin
- UMR1163 Biodiversité et Biotechnologie Fongiques, INRAE, Aix Marseille University, Marseille, France
| | - Bastien Bissaro
- UMR1163 Biodiversité et Biotechnologie Fongiques, INRAE, Aix Marseille University, Marseille, France.
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Gao W, Li T, Zhou H, Ju J, Yin H. Carbohydrate-binding modules enhance H 2O 2 tolerance by promoting lytic polysaccharide monooxygenase active site H 2O 2 consumption. J Biol Chem 2024; 300:105573. [PMID: 38122901 PMCID: PMC10825053 DOI: 10.1016/j.jbc.2023.105573] [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: 09/12/2023] [Revised: 11/26/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) oxidatively depolymerize recalcitrant polysaccharides, which is important for biomass conversion. The catalytic domains of many LPMOs are linked to carbohydrate-binding modules (CBMs) through flexible linkers, but the function of these CBMs in LPMO catalysis is not well understood. In this study, we utilized MtLPMO9L and MtLPMO9G derived from Myceliophthora thermophila to investigate the impact of CBMs on LPMO activity, with particular emphasis on their influence on H2O2 tolerance. Using truncated forms of MtLPMO9G generated by removing the CBM, we found reduced substrate binding affinity and enzymatic activity. Conversely, when the CBM was fused to the C terminus of the single-domain MtLPMO9L to create MtLPMO9L-CBM, we observed a substantial improvement in substrate binding affinity, enzymatic activity, and notably, H2O2 tolerance. Furthermore, molecular dynamics simulations confirmed that the CBM fusion enhances the proximity of the active site to the substrate, thereby promoting multilocal cleavage and impacting the exposure of the copper active site to H2O2. Importantly, the fusion of CBM resulted in more efficient consumption of H2O2 by LPMO, leading to improved enzymatic activity and reduced auto-oxidative damage of the copper active center.
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Affiliation(s)
- Wa Gao
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China; University of Chinese Academy of Sciences, Beijing, China
| | - Tang Li
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China
| | - Haichuan Zhou
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China
| | - Jiu Ju
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China
| | - Heng Yin
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Dalian Technology Innovation Center for Green Agriculture, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China; University of Chinese Academy of Sciences, Beijing, China.
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8
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Sun N, Wang J, Shi H, Li X, Guo S, Wang Y, Hu S, Liu R, Gao C. Compound effect and mechanism of oxidative damage induced by nanoplastics and benzo [a] pyrene. JOURNAL OF HAZARDOUS MATERIALS 2023; 460:132513. [PMID: 37708649 DOI: 10.1016/j.jhazmat.2023.132513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 09/03/2023] [Accepted: 09/07/2023] [Indexed: 09/16/2023]
Abstract
Nanoplastics and polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in soil environments. In order to objectively evaluate the toxic interaction between polystyrene nanoplastics (PS NPs) and benzo [a] pyrene (BaP), oxidative damage at the level of earthworm cells and biomacromolecules was investigated by experiments combined with molecular dynamics simulation. Studies on cells reveal that PS NPs and BaP had synergistic toxicity when it came to causing oxidative stress. Cellular reactive oxygen species (ROS) levels under combined pollutant exposure were 24% and 19% higher, respectively than when PS NPs and BaP were exposed alone (compared to the blank group). In addition, BaP and PS NPs inhibited the ability of CAT to decompose H2O2 by affecting the structure of the proximal amino acid Tyr 357 in the active center of CAT, which exacerbated oxidative stress to a certain extent. Therefore, the synergistic toxic effect of BaP and PS NPs is due to the mutual complement of the two to the induction of protein structural looseness, and the strengthening of the stability of the conjugate (CAT-BaP-PS) under the weak interaction. This work provides a new perspective and approach on how to talk about the toxicity of combined pollutants.
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Affiliation(s)
- Ning Sun
- School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China
| | - Jinhu Wang
- College of Chemistry, Chemical Engineering and Material Science, Zaozhuang University, Zaozhuang, Shandong Province 277160, PR China
| | - Huijian Shi
- School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China
| | - Xiangxiang Li
- School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China
| | - Shuqi Guo
- School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China
| | - Yaoyue Wang
- School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China
| | - Shaoyang Hu
- School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China
| | - Rutao Liu
- School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China.
| | - Canzhu Gao
- School of Environmental Science and Engineering, Shandong University, China-America CRC for Environment & Health, Shandong Province, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China.
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Hamre AG, Al-Sadawi R, Johannesen KM, Bisarro B, Kjendseth ÅR, Leiros HKS, Sørlie M. Initial characterization of an iron superoxide dismutase from Thermobifida fusca. J Biol Inorg Chem 2023; 28:689-698. [PMID: 37725277 PMCID: PMC10520107 DOI: 10.1007/s00775-023-02019-9] [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: 11/16/2022] [Accepted: 08/24/2023] [Indexed: 09/21/2023]
Abstract
Superoxide dismutases (SODs) are enzymes that catalyze the dismutation of the superoxide radical anion into O2 and H2O2 in a two-step reaction. They are ubiquitous to all forms of life and four different types of metal centers are detected, dividing this class of enzymes into Cu-/Zn-, Ni-, Mn-, and Fe-SODs. In this study, a superoxide dismutase from the thermophilic bacteria Thermobifida fusca (TfSOD) was cloned and expressed before the recombinant enzyme was characterized. The enzyme was found to be active for superoxide dismutation measured by inhibition of cytochrome c oxidation and the inhibition of the autoxidation of pyrogallol. Its pH-optimum was determined to be 7.5, while it has a broad temperature optimum ranging from 20 to 90 °C. Combined with the Tm that was found to be 78.5 ± 0.5 °C at pH 8.0, TfSOD can be defined as a thermostable enzyme. Moreover, the crystal structure of TfSOD was determined and refined to 1.25 Å resolution. With electron paramagnetic resonance spectroscopy, it was confirmed that iron is the metal co-factor of TfSOD. The cell potential (Em) for the TfSOD-Fe3+/TfSOD-Fe2+ redox couple was determined to be 287 mV.
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Affiliation(s)
- Anne Grethe Hamre
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Rim Al-Sadawi
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Kirsti Merete Johannesen
- Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, 9037, Tromsö, Norway
| | - Bastien Bisarro
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Åsmund Røhr Kjendseth
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Hanna-Kirsti S Leiros
- Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, 9037, Tromsö, Norway
| | - Morten Sørlie
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway.
- Department for Physics and Technology, Faculty of Science and Technology, UiT The Arctic University of Norway, 9037, Tromsö, Norway.
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10
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Kuusk S, Eijsink VGH, Väljamäe P. The "life-span" of lytic polysaccharide monooxygenases (LPMOs) correlates to the number of turnovers in the reductant peroxidase reaction. J Biol Chem 2023; 299:105094. [PMID: 37507015 PMCID: PMC10458328 DOI: 10.1016/j.jbc.2023.105094] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 07/02/2023] [Accepted: 07/22/2023] [Indexed: 07/30/2023] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are monocopper enzymes that degrade the insoluble crystalline polysaccharides cellulose and chitin. Besides the H2O2 cosubstrate, the cleavage of glycosidic bonds by LPMOs depends on the presence of a reductant needed to bring the enzyme into its reduced, catalytically active Cu(I) state. Reduced LPMOs that are not bound to substrate catalyze reductant peroxidase reactions, which may lead to oxidative damage and irreversible inactivation of the enzyme. However, the kinetics of this reaction remain largely unknown, as do possible variations between LPMOs belonging to different families. Here, we describe the kinetic characterization of two fungal family AA9 LPMOs, TrAA9A of Trichoderma reesei and NcAA9C of Neurospora crassa, and two bacterial AA10 LPMOs, ScAA10C of Streptomyces coelicolor and SmAA10A of Serratia marcescens. We found peroxidation of ascorbic acid and methyl-hydroquinone resulted in the same probability of LPMO inactivation (pi), suggesting that inactivation is independent of the nature of the reductant. We showed the fungal enzymes were clearly more resistant toward inactivation, having pi values of less than 0.01, whereas the pi for SmAA10A was an order of magnitude higher. However, the fungal enzymes also showed higher catalytic efficiencies (kcat/KM(H2O2)) for the reductant peroxidase reaction. This inverse linear correlation between the kcat/KM(H2O2) and pi suggests that, although having different life spans in terms of the number of turnovers in the reductant peroxidase reaction, LPMOs that are not bound to substrates have similar half-lives. These findings have not only potential biological but also industrial implications.
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Affiliation(s)
- Silja Kuusk
- Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Sciences, Ås, Norway
| | - Priit Väljamäe
- Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia.
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11
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Tuveng TR, Østby H, Tamburrini KC, Bissaro B, Hegnar OA, Stepnov AA, Várnai A, Berrin JG, Eijsink VGH. Revisiting the AA14 family of lytic polysaccharide monooxygenases and their catalytic activity. FEBS Lett 2023; 597:2086-2102. [PMID: 37418595 DOI: 10.1002/1873-3468.14694] [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: 03/31/2023] [Revised: 06/08/2023] [Accepted: 06/26/2023] [Indexed: 07/09/2023]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) belonging to the AA14 family are believed to contribute to the enzymatic degradation of lignocellulosic biomass by specifically acting on xylan in recalcitrant cellulose-xylan complexes. Functional characterization of an AA14 LPMO from Trichoderma reesei, TrAA14A, and a re-evaluation of the properties of the previously described AA14 from Pycnoporus coccineus, PcoAA14A, showed that these proteins have oxidase and peroxidase activities that are common for LPMOs. However, we were not able to detect activity on cellulose-associated xylan or any other tested polysaccharide substrate, meaning that the substrate of these enzymes remains unknown. Next to raising questions regarding the true nature of AA14 LPMOs, the present data illustrate possible pitfalls in the functional characterization of these intriguing enzymes.
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Affiliation(s)
- Tina R Tuveng
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Heidi Østby
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Ketty C Tamburrini
- INRAE, Aix Marseille Univ, UMR1163 Biodiversité et Biotechnologie Fongiques, Marseille, France
| | - Bastien Bissaro
- INRAE, Aix Marseille Univ, UMR1163 Biodiversité et Biotechnologie Fongiques, Marseille, France
| | - Olav A Hegnar
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Anton A Stepnov
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Anikó Várnai
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Jean-Guy Berrin
- INRAE, Aix Marseille Univ, UMR1163 Biodiversité et Biotechnologie Fongiques, Marseille, France
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology, and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
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12
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Berhe MH, Song X, Yao L. Improving the Enzymatic Activity and Stability of a Lytic Polysaccharide Monooxygenase. Int J Mol Sci 2023; 24:ijms24108963. [PMID: 37240310 DOI: 10.3390/ijms24108963] [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: 03/16/2023] [Revised: 05/12/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
Lytic Polysaccharide Monooxygenases (LPMOs) are copper-dependent enzymes that play a pivotal role in the enzymatic conversion of the most recalcitrant polysaccharides, such as cellulose and chitin. Hence, protein engineering is highly required to enhance their catalytic efficiencies. To this effect, we optimized the protein sequence encoding for an LPMO from Bacillus amyloliquefaciens (BaLPMO10A) using the sequence consensus method. Enzyme activity was determined using the chromogenic substrate 2,6-Dimethoxyphenol (2,6-DMP). Compared with the wild type (WT), the variants exhibit up to a 93.7% increase in activity against 2,6-DMP. We also showed that BaLPMO10A can hydrolyze p-nitrophenyl-β-D-cellobioside (PNPC), carboxymethylcellulose (CMC), and phosphoric acid-swollen cellulose (PASC). In addition to this, we investigated the degradation potential of BaLPMO10A against various substrates such as PASC, filter paper (FP), and Avicel, in synergy with the commercial cellulase, and it showed up to 2.7-, 2.0- and 1.9-fold increases in production with the substrates PASC, FP, and Avicel, respectively, compared to cellulase alone. Moreover, we examined the thermostability of BaLPMO10A. The mutants exhibited enhanced thermostability with an apparent melting temperature increase of up to 7.5 °C compared to the WT. The engineered BaLPMO10A with higher activity and thermal stability provides a better tool for cellulose depolymerization.
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Affiliation(s)
- Miesho Hadush Berhe
- Qingdao New Energy Shandong Laboratory, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- Shandong Energy Institute, Qingdao 266101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Department of Biotechnology, College of Natural and Computational Sciences, Aksum University, Axum 1010, Ethiopia
| | - Xiangfei Song
- Qingdao New Energy Shandong Laboratory, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- Shandong Energy Institute, Qingdao 266101, China
| | - Lishan Yao
- Qingdao New Energy Shandong Laboratory, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China
- Shandong Energy Institute, Qingdao 266101, China
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13
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Liu Y, Ma W, Fang X. The Role of the Residue at Position 2 in the Catalytic Activity of AA9 Lytic Polysaccharide Monooxygenases. Int J Mol Sci 2023; 24:ijms24098300. [PMID: 37176008 PMCID: PMC10179388 DOI: 10.3390/ijms24098300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/18/2023] [Accepted: 04/27/2023] [Indexed: 05/15/2023] Open
Abstract
AA9 lytic polysaccharide monooxygenases (LPMOs) are copper-dependent metalloenzymes that play a major role in cellulose degradation and plant infection. Understanding the AA9 LPMO mechanism would facilitate the improvement of plant pathogen control and the industrial application of LPMOs. Herein, via point mutation, we investigated the role of glycine 2 residue in cellulose degradation by Thermoascus aurantiacus AA9 LPMOs (TaAA9). A computational simulation showed that increasing the steric properties of this residue by replacing glycine with threonine or tyrosine altered the H-bonding network of the copper center and copper coordination geometry, decreased the surface charge of the catalytic center, weakened the TaAA9-substrate interaction, and enhanced TaAA9-product binding. Compared with wild-type TaAA9, G2T-TaAA9 and G2Y-TaAA9 variants showed attenuated copper affinity, reduced oxidative product diversity and decreased substrate Avicel binding, as determined using ITC, MALDI-TOF/TOF MS and cellulose binding analyses, respectively. Consistently, the enzymatic activity and synergy with cellulase of the G2T-TaAA9 and G2Y-TaAA9 variants were lower than those of TaAA9. Hence, the investigated residue crucially affects the catalytic activity of AA9 LPMOs, and we propose that the electropositivity of copper may correlate with AA9 LPMO activity. Thus, the relationship among the amino acid at position 2, surface charge and catalytic activity may facilitate an understanding of the proteins in AA9 LPMOs.
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Affiliation(s)
- Yucui Liu
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao 266237, China
| | - Wei Ma
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao 266237, China
| | - Xu Fang
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao 266237, China
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14
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Yu X, Zhao Y, Yu J, Wang L. Recent advances in the efficient degradation of lignocellulosic metabolic networks by lytic polysaccharide monooxygenase. Acta Biochim Biophys Sin (Shanghai) 2023; 55:529-539. [PMID: 37036250 DOI: 10.3724/abbs.2023059] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2023] Open
Abstract
Along with long-term evolution, the plant cell wall generates lignocellulose and other anti-degradation barriers to confront hydrolysis by fungi. Lytic polysaccharide monooxygenase (LPMO) is a newly defined oxidase in lignocellulosic degradation systems that significantly fuels hydrolysis. LPMO accepts electrons from wide sources, such as cellobiose dehydrogenase (CDH), glucose-methanol-choline (GMC) oxidoreductases, and small phenols. In addition, the extracellular cometabolic network formed by cosubstrates improves the degradation efficiency, forming a stable and efficient lignocellulose degradation system. In recent years, using structural proteomics to explore the internal structure and the complex redox system of LPMOs has become a research hotspot. In this review, the diversity of LPMOs, catalytic domains, carbohydrate binding modules, direct electron transfer with CDH, cosubstrates, and degradation networks of LPMOs are explored, which can provide a systematic reference for the application of lignocellulosic degradation systems in industrial approaches.
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Affiliation(s)
- Xinran Yu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Yue Zhao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
| | - Junhong Yu
- State Key Laboratory of Biological Fermentation Engineering of Beer, Qingdao 266035, China
| | - Lushan Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, China
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15
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Wang J, Shirvani H, Zhao H, Kibria MG, Hu J. Lignocellulosic biomass valorization via bio-photo/electro hybrid catalytic systems. Biotechnol Adv 2023; 66:108157. [PMID: 37084800 DOI: 10.1016/j.biotechadv.2023.108157] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 03/23/2023] [Accepted: 04/17/2023] [Indexed: 04/23/2023]
Abstract
Lignocellulosic biomass valorization is regarded as a promising approach to alleviate energy crisis and achieve carbon neutrality. Bioactive enzymes have attracted great attention and been commonly applied for biomass valorization owing to their high selectivity and catalytic efficiency under environmentally benign reaction conditions. Same as biocatalysis, photo-/electro-catalysis also happens at mild conditions (i.e., near ambient temperature and pressure). Therefore, the combination of these different catalytic approaches to benefit from their resulting synergy is appealing. In such hybrid systems, harness of renewable energy from the photo-/electro-catalytic compartment can be combined with the unique selectivity of biocatalysts, therefore providing a more sustainable and greener approach to obtain fuels and value-added chemicals from biomass. In this review, we firstly introduce the pros/cons, classifications, and the applications of photo-/electro-enzyme coupled systems. Then we focus on the fundamentals and comprehensive applications of the most representative biomass-active enzymes including lytic polysaccharide monooxygenases (LPMOs), glucose oxidase (GOD)/dehydrogenase (GDH) and lignin peroxidase (LiP), together with other biomass-active enzymes in the photo-/electro- enzyme coupled systems. Finally, we propose current deficiencies and future perspectives of biomass-active enzymes to be applied in the hybrid catalytic systems for global biomass valorization.
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Affiliation(s)
- Jiu Wang
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive, NW, Calgary, Alberta, Canada
| | - Hamed Shirvani
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive, NW, Calgary, Alberta, Canada
| | - Heng Zhao
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive, NW, Calgary, Alberta, Canada
| | - Md Golam Kibria
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive, NW, Calgary, Alberta, Canada.
| | - Jinguang Hu
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive, NW, Calgary, Alberta, Canada.
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16
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Kommedal EG, Angeltveit CF, Klau LJ, Ayuso-Fernández I, Arstad B, Antonsen SG, Stenstrøm Y, Ekeberg D, Gírio F, Carvalheiro F, Horn SJ, Aachmann FL, Eijsink VGH. Visible light-exposed lignin facilitates cellulose solubilization by lytic polysaccharide monooxygenases. Nat Commun 2023; 14:1063. [PMID: 36828821 PMCID: PMC9958194 DOI: 10.1038/s41467-023-36660-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 02/10/2023] [Indexed: 02/26/2023] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) catalyze oxidative cleavage of crystalline polysaccharides such as cellulose and are crucial for the conversion of plant biomass in Nature and in industrial applications. Sunlight promotes microbial conversion of plant litter; this effect has been attributed to photochemical degradation of lignin, a major redox-active component of secondary plant cell walls that limits enzyme access to the cell wall carbohydrates. Here, we show that exposing lignin to visible light facilitates cellulose solubilization by promoting formation of H2O2 that fuels LPMO catalysis. Light-driven H2O2 formation is accompanied by oxidation of ring-conjugated olefins in the lignin, while LPMO-catalyzed oxidation of phenolic hydroxyls leads to the required priming reduction of the enzyme. The discovery that light-driven abiotic reactions in Nature can fuel H2O2-dependent redox enzymes involved in deconstructing lignocellulose may offer opportunities for bioprocessing and provides an enzymatic explanation for the known effect of visible light on biomass conversion.
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Affiliation(s)
- Eirik G Kommedal
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Camilla F Angeltveit
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Leesa J Klau
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Iván Ayuso-Fernández
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Bjørnar Arstad
- SINTEF Industry, Process Chemistry and Functional Materials, 0373, Oslo, Norway
| | - Simen G Antonsen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Yngve Stenstrøm
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Dag Ekeberg
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Francisco Gírio
- National Laboratory of Energy and Geology (LNEG), 1649-038, Lisboa, Portugal
| | | | - Svein J Horn
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway
| | - Finn Lillelund Aachmann
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432, Ås, Norway.
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17
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Revisiting the role of electron donors in lytic polysaccharide monooxygenase biochemistry. Essays Biochem 2023; 67:585-595. [PMID: 36748351 PMCID: PMC10154616 DOI: 10.1042/ebc20220164] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 02/08/2023]
Abstract
The plant cell wall is rich in carbohydrates and many fungi and bacteria have evolved to take advantage of this carbon source. These carbohydrates are largely locked away in polysaccharides and so these organisms deploy a range of enzymes that can liberate individual sugars from these challenging substrates. Glycoside hydrolases (GHs) are the enzymes that are largely responsible for bringing about this sugar release; however, 12 years ago, a family of enzymes known as lytic polysaccharide monooxygenases (LPMOs) were also shown to be of key importance in this process. LPMOs are copper-dependent oxidative enzymes that can introduce chain breaks within polysaccharide chains. Initial work demonstrated that they could activate O2 to attack the substrate through a reaction that most likely required multiple electrons to be delivered to the enzyme. More recently, it has emerged that LPMO kinetics are significantly improved if H2O2 is supplied to the enzyme as a cosubstrate instead of O2. Only a single electron is required to activate an LPMO and H2O2 cosubstrate and the enzyme has been shown to catalyse multiple turnovers following the initial one-electron reduction of the copper, which is not possible if O2 is used. This has led to further studies of the roles of the electron donor in LPMO biochemistry, and this review aims to highlight recent findings in this area and consider how ongoing research could impact our understanding of the interplay between redox processes in nature.
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18
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Schwaiger L, Zenone A, Csarman F, Ludwig R. Continuous photometric activity assays for lytic polysaccharide monooxygenase-Critical assessment and practical considerations. Methods Enzymol 2022; 679:381-404. [PMID: 36682872 DOI: 10.1016/bs.mie.2022.08.054] [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: 12/31/2022]
Abstract
Lytic polysaccharide monooxygenase (LPMO) is a monocopper-dependent enzyme that cleaves glycosidic bonds by using an oxidative mechanism. In nature, they act in concert with cellobiohydrolases to facilitate the efficient degradation of lignocellulosic biomass. After more than a decade of LPMO research, it has become evident that LPMOs are abundant in all domains of life and fulfill a diverse range of biological functions. Independent of their biological function and the preferred polysaccharide substrate, studying and characterizing LPMOs is tedious and so far mostly relied on the discontinuous analysis of the solubilized reaction products by HPLC/MS-based methods. In the absence of appropriate substrates, LPMOs can engage in two off-pathway reactions, i.e., an oxidase and a peroxidase-like activity. These futile reactions have been exploited to set up easy-to-use continuous spectroscopic assays. As the natural substrates of newly discovered LPMOs are often unknown, widely applicable, simple, reliable, and robust spectroscopic assays are required to monitor LPMO expression and to perform initial biochemical characterizations, e.g., thermal stability measurements. Here we provide detailed descriptions and practical protocols to perform continuous photometric assays using either 2,6-dimethoxyphenol (2,6-DMP) or hydrocoerulignone as colorimetric substrates as a broadly applicable assay for a range of LPMOs. In addition, a turbidimetric measurement is described as the currently only method available to continuously monitor LPMOs acting on amorphous cellulose.
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Affiliation(s)
- Lorenz Schwaiger
- Department of Food Science and Technology, Institute of Food Technology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Alice Zenone
- Department of Food Science and Technology, Institute of Food Technology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Florian Csarman
- Department of Food Science and Technology, Institute of Food Technology, University of Natural Resources and Life Sciences, Vienna, Austria.
| | - Roland Ludwig
- Department of Food Science and Technology, Institute of Food Technology, University of Natural Resources and Life Sciences, Vienna, Austria
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19
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Abstract
Lytic polysaccharide monooxygenases (LPMOs) are unique redox enzymes capable of disrupting the crystalline surfaces of industry-relevant recalcitrant polysaccharides, such as chitin and cellulose. Historically, LPMOs were thought to be slow enzymes relying on O2 as the co-substrate, but it is now clear that these enzymes prefer H2O2, allowing for fast depolymerization of polysaccharides through a peroxygenase reaction. Thus, quantifying H2O2 in LPMO reaction set-ups is of a great interest. The horseradish peroxidase (HRP)/Amplex Red (AR) assay is one of the most popular and accessible tools for measuring hydrogen peroxide. This assay has been used in various types of biological and biochemical studies, including LPMO research, but suffers from pitfalls that need to be accounted for. In this Chapter, we discuss this method and its use for assessing the often rate-limiting in situ formation of H2O2 in LPMO reactions. We show that, after accounting for multiple potential side reactions, quantitative data on H2O2 production obtained with the HRP/Amplex Red assay provide useful clues for understanding the catalytic activity of LPMOs, including the impact of reductants and transition metal ions.
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Affiliation(s)
- Anton A Stepnov
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Ås, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Ås, Norway.
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20
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2019-2020. MASS SPECTROMETRY REVIEWS 2022:e21806. [PMID: 36468275 DOI: 10.1002/mas.21806] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
This review is the tenth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2020. Also included are papers that describe methods appropriate to analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. The review is basically divided into three sections: (1) general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation, quantification and the use of arrays. (2) Applications to various structural types such as oligo- and polysaccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals, and (3) other areas such as medicine, industrial processes and glycan synthesis where MALDI is extensively used. Much of the material relating to applications is presented in tabular form. The reported work shows increasing use of incorporation of new techniques such as ion mobility and the enormous impact that MALDI imaging is having. MALDI, although invented nearly 40 years ago is still an ideal technique for carbohydrate analysis and advancements in the technique and range of applications show little sign of diminishing.
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Affiliation(s)
- David J Harvey
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford, UK
- Department of Chemistry, University of Oxford, Oxford, Oxfordshire, United Kingdom
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21
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Wu S, Tian J, Xie N, Adnan M, Wang J, Liu G. A sensitive, accurate, and high-throughput gluco-oligosaccharide oxidase-based HRP colorimetric method for assaying lytic polysaccharide monooxygenase activity. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:15. [PMID: 35418300 PMCID: PMC8830019 DOI: 10.1186/s13068-022-02112-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 01/28/2022] [Indexed: 11/17/2022]
Abstract
Background The AA9 (auxiliary activities) family of lytic polysaccharide monooxygenases (AA9 LPMOs) is a ubiquitous and diverse group of enzymes in the fungal kingdom. They catalyse the oxidative cleavage of glycosidic bonds in lignocellulose and exhibit great potential for biorefinery applications. Robust, high-throughput and direct methods for assaying AA9 LPMO activity, which are prerequisites for screening LPMOs with excellent properties, are still lacking. Here, we present a gluco-oligosaccharide oxidase (GOOX)-based horseradish peroxidase (HRP) colorimetric method for assaying AA9 LPMO activity. Results We cloned and expressed a GOOX gene from Sarocladium strictum in Trichoderma reesei, purified the recombinant SsGOOX, validated its properties, and developed an SsGOOX-based HRP colorimetric method for assaying cellobiose concentrations. Then, we expressed two AA9 LPMOs from Thielavia terrestris, TtAA9F and TtAA9G, in T. reesei, purified the recombinant proteins, and analysed their product profiles and regioselectivity towards phosphoric acid swollen cellulose (PASC). TtAA9F was characterized as a C1-type (class 1) LPMO, while TtAA9G was characterized as a C4-type (class 2) LPMO. Finally, the SsGOOX-based HRP colorimetric method was used to quantify the total concentration of reducing lytic products from the LPMO reaction, and the activities of both the C1- and C4-type LPMOs were analysed. These LPMOs could be effectively analysed with limits of detection (LoDs) less than 30 nmol/L, and standard curves between the A515 and LPMO concentrations with determination coefficients greater than 0.994 were obtained. Conclusions A novel, sensitive and accurate assay method that directly targets the main activity of both C1- and C4-type AA9 LPMOs was established. This method is easy to use and could be performed on a microtiter plate for high-throughput screening of AA9 LPMOs with desirable properties. Supplementary Information The online version contains supplementary material available at 10.1186/s13068-022-02112-2.
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22
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Controlled depolymerization of cellulose by photoelectrochemical bioreactor using a lytic polysaccharide monooxygenase. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2022.108597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Natural photoredox catalysts promote light-driven lytic polysaccharide monooxygenase reactions and enzymatic turnover of biomass. Proc Natl Acad Sci U S A 2022; 119:e2204510119. [PMID: 35969781 PMCID: PMC9407654 DOI: 10.1073/pnas.2204510119] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) catalyze oxidative cleavage of crystalline polysaccharides such as cellulose and chitin and are important for biomass conversion in the biosphere as well as in biorefineries. The target polysaccharides of LPMOs naturally occur in copolymeric structures such as plant cell walls and insect cuticles that are rich in phenolic compounds, which contribute rigidity and stiffness to these materials. Since these phenolics may be photoactive and since LPMO action depends on reducing equivalents, we hypothesized that LPMOs may enable light-driven biomass conversion. Here, we show that redox compounds naturally present in shed insect exoskeletons enable harvesting of light energy to drive LPMO reactions and thus biomass conversion. The primary underlying mechanism is that irradiation of exoskeletons with visible light leads to the generation of H2O2, which fuels LPMO peroxygenase reactions. Experiments with a cellulose model substrate show that the impact of light depends on both light and exoskeleton dosage and that light-driven LPMO activity is inhibited by a competing H2O2-consuming enzyme. Degradation experiments with the chitin-rich exoskeletons themselves show that solubilization of chitin by a chitin-active LPMO is promoted by light. The fact that LPMO reactions, and likely reactions catalyzed by other biomass-converting redox enzymes, are fueled by light-driven abiotic reactions in nature provides an enzyme-based explanation for the known impact of visible light on biomass conversion.
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Wang D, Kao MR, Li J, Sun P, Meng Q, Vyas A, Liang PH, Wang YS, Hsieh YSY. Novel Two-Step Process in Cellulose Depolymerization: Hematite-Mediated Photocatalysis by Lytic Polysaccharide Monooxygenase and Fenton Reaction. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:9941-9947. [PMID: 35921143 PMCID: PMC9389612 DOI: 10.1021/acs.jafc.2c02445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
To transform cellulose from biomass into fermentable sugars for biofuel production requires efficient enzymatic degradation of cellulosic feedstocks. The recently discovered family of oxidative enzymes, lytic polysaccharide monooxygenase (LPMO), has a high potential for industrial biorefinery, but its energy efficiency and scalability still have room for improvement. Hematite (α-Fe2O3) can act as a photocatalyst by providing electrons to LPMO-catalyzed reactions, is low cost, and is found abundantly on the Earth's surface. Here, we designed a composite enzymatic photocatalysis-Fenton reaction system based on nano-α-Fe2O3. The feasibility of using α-Fe2O3 nanoparticles as a composite catalyst to facilitate LPMO-catalyzed cellulose oxidative degradation in water was tested. Furthermore, a light-induced Fenton reaction was integrated to increase the liquefaction yield of cellulose. The innovative approach finalized the cellulose degradation process with a total liquefaction yield of 93%. Nevertheless, the complex chemical reactions and products involved in this system require further investigation.
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Affiliation(s)
- Damao Wang
- College
of Food Science, Southwest University, Chongqing 400715, PR China
- Division
of Glycoscience, Department of Chemistry, School of Engineering Sciences
in Chemistry, Biotechnology and Health, Royal Institute of Technology (KTH), AlbaNova University Center, Stockholm SE10691, Sweden
- School
of Pharmacy, College of Pharmacy, Taiwan
Medical University, Taipei 110, Taiwan
| | - Mu-Rong Kao
- School
of Pharmacy, College of Pharmacy, Taiwan
Medical University, Taipei 110, Taiwan
| | - Jing Li
- Division
of Glycoscience, Department of Chemistry, School of Engineering Sciences
in Chemistry, Biotechnology and Health, Royal Institute of Technology (KTH), AlbaNova University Center, Stockholm SE10691, Sweden
- College
of Life Sciences, Shanghai Normal University, Shanghai 220234, PR China
| | - Peicheng Sun
- Laboratory
of Food Chemistry, Wageningen University
& Research, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands
| | - Qijun Meng
- Division
of Organic Chemistry, Department of Chemistry, School of Engineering
Sciences in Chemistry, Biotechnology and Health, Royal Institute of Technology (KTH), Stockholm SE1004, Sweden
| | - Anisha Vyas
- Division
of Glycoscience, Department of Chemistry, School of Engineering Sciences
in Chemistry, Biotechnology and Health, Royal Institute of Technology (KTH), AlbaNova University Center, Stockholm SE10691, Sweden
- Institute
of Biotechnology and Biochemical Engineering, Graz University of Technology, 8010 Graz, Austria
| | - Pi-Hui Liang
- College
of Pharmacy, National Taiwan University, Taipei 100, Taiwan
| | - Yane-Shih Wang
- Institute
of Biological Chemistry, Academia Sinica, Taipei 11529, Taiwan
| | - Yves S. Y. Hsieh
- Division
of Glycoscience, Department of Chemistry, School of Engineering Sciences
in Chemistry, Biotechnology and Health, Royal Institute of Technology (KTH), AlbaNova University Center, Stockholm SE10691, Sweden
- School
of Pharmacy, College of Pharmacy, Taiwan
Medical University, Taipei 110, Taiwan
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25
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Long L, Hu Y, Sun F, Gao W, Hao Z, Yin H. Advances in lytic polysaccharide monooxygenases with the cellulose-degrading auxiliary activity family 9 to facilitate cellulose degradation for biorefinery. Int J Biol Macromol 2022; 219:68-83. [PMID: 35931294 DOI: 10.1016/j.ijbiomac.2022.07.240] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 07/29/2022] [Accepted: 07/30/2022] [Indexed: 11/18/2022]
Abstract
One crucial step in processing the recalcitrant lignocellulosic biomass is the fast hydrolysis of natural cellulose to fermentable sugars that can be subsequently converted to biofuels and bio-based chemicals. Recent studies have shown that lytic polysaccharide monooxygenase (LPMOs) with auxiliary activity family 9 (AA9) are capable of efficiently depolymerizing the crystalline cellulose via regioselective oxidation reaction. Intriguingly, the catalysis by AA9 LPMOs requires reductant to provide electrons, and lignin and its phenolic derivatives can be oxidized, releasing reductant to activate the reaction. The activity of AA9 LPMOs can be enhanced by in-situ generation of H2O2 in the presence of O2. Although scientific understanding of these enzymes remains somewhat unknown or controversial, structure modifications on AA9 LPMOs through protein engineering have emerged in recent years, which are prerequisite for their extensive applications in the development of cellulase-mediated lignocellulosic biorefinery processes. In this review, we critically comment on advances in studies for AA9 LPMOs, i.e., characteristic of AA9 LPMOs catalysis, external electron donors to AA9 LPMOs, especially the role of the oxidization of lignin and its derivatives, and AA9 LPMOs protein engineering as well as their extensive applications in the bioprocessing of lignocellulosic biomass. Perspectives are also highlighted for addressing the challenges.
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Affiliation(s)
- Lingfeng Long
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Yun Hu
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Fubao Sun
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
| | - Wa Gao
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS(, Dalian 116023, China
| | - Zhikui Hao
- Institute of Applied Biotechnology, School of Medicine and Pharmaceutical Engineering, Taizhou Vocational and Technical College, Taizhou 318000, China
| | - Heng Yin
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS(, Dalian 116023, China
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Stepnov AA, Eijsink VGH, Forsberg Z. Enhanced in situ H 2O 2 production explains synergy between an LPMO with a cellulose-binding domain and a single-domain LPMO. Sci Rep 2022; 12:6129. [PMID: 35414104 PMCID: PMC9005612 DOI: 10.1038/s41598-022-10096-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 03/29/2022] [Indexed: 02/02/2023] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are mono-copper enzymes that catalyze oxidative depolymerization of recalcitrant substrates such as chitin or cellulose. Recent work has shown that LPMOs catalyze fast peroxygenase reactions and that, under commonly used reaction set-ups, access to in situ generated H2O2 likely limits catalysis. Based on a hypothesis that the impact of a cellulose-binding module (CBM) on LPMO activity could relate to changes in in situ H2O2 production, we have assessed the interplay between CBM-containing ScLPMO10C and its truncated form comprising the catalytic domain only (ScLPMO10CTR). The results show that truncation of the linker and CBM leads to elevated H2O2 production and decreased enzyme stability. Most interestingly, combining the two enzyme forms yields strong synergistic effects, which are due to the combination of high H2O2 generation by ScLPMO10CTR and efficient productive use of H2O2 by the full-length enzyme. Thus, cellulose degradation becomes faster, while enzyme inactivation due to off-pathway reactions with excess H2O2 is reduced. These results underpin the complexity of ascorbic acid-driven LPMO reactions and reveal a potential mechanism for how LPMOs may interact synergistically during cellulose degradation.
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Affiliation(s)
- Anton A Stepnov
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Sciences, 1432, Ås, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Sciences, 1432, Ås, Norway.
| | - Zarah Forsberg
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Sciences, 1432, Ås, Norway.
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Mattila H, Österman-Udd J, Mali T, Lundell T. Basidiomycota Fungi and ROS: Genomic Perspective on Key Enzymes Involved in Generation and Mitigation of Reactive Oxygen Species. FRONTIERS IN FUNGAL BIOLOGY 2022; 3:837605. [PMID: 37746164 PMCID: PMC10512322 DOI: 10.3389/ffunb.2022.837605] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 02/21/2022] [Indexed: 09/26/2023]
Abstract
Our review includes a genomic survey of a multitude of reactive oxygen species (ROS) related intra- and extracellular enzymes and proteins among fungi of Basidiomycota, following their taxonomic classification within the systematic classes and orders, and focusing on different fungal lifestyles (saprobic, symbiotic, pathogenic). Intra- and extracellular ROS metabolism-involved enzymes (49 different protein families, summing 4170 protein models) were searched as protein encoding genes among 63 genomes selected according to current taxonomy. Extracellular and intracellular ROS metabolism and mechanisms in Basidiomycota are illustrated in detail. In brief, it may be concluded that differences between the set of extracellular enzymes activated by ROS, especially by H2O2, and involved in generation of H2O2, follow the differences in fungal lifestyles. The wood and plant biomass degrading white-rot fungi and the litter-decomposing species of Agaricomycetes contain the highest counts for genes encoding various extracellular peroxidases, mono- and peroxygenases, and oxidases. These findings further confirm the necessity of the multigene families of various extracellular oxidoreductases for efficient and complete degradation of wood lignocelluloses by fungi. High variations in the sizes of the extracellular ROS-involved gene families were found, however, among species with mycorrhizal symbiotic lifestyle. In addition, there are some differences among the sets of intracellular thiol-mediation involving proteins, and existence of enzyme mechanisms for quenching of intracellular H2O2 and ROS. In animal- and plant-pathogenic species, extracellular ROS enzymes are absent or rare. In these fungi, intracellular peroxidases are seemingly in minor role than in the independent saprobic, filamentous species of Basidiomycota. Noteworthy is that our genomic survey and review of the literature point to that there are differences both in generation of extracellular ROS as well as in mechanisms of response to oxidative stress and mitigation of ROS between fungi of Basidiomycota and Ascomycota.
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Affiliation(s)
| | | | | | - Taina Lundell
- Department of Microbiology, Faculty of Agriculture and Forestry, Viikki Campus, University of Helsinki, Helsinki, Finland
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Vandhana TM, Reyre JL, Sushmaa D, Berrin JG, Bissaro B, Madhuprakash J. On the expansion of biological functions of lytic polysaccharide monooxygenases. THE NEW PHYTOLOGIST 2022; 233:2380-2396. [PMID: 34918344 DOI: 10.1111/nph.17921] [Citation(s) in RCA: 50] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 11/19/2021] [Indexed: 05/21/2023]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) constitute an enigmatic class of enzymes, the discovery of which has opened up a new arena of riveting research. LPMOs can oxidatively cleave the glycosidic bonds found in carbohydrate polymers enabling the depolymerisation of recalcitrant biomasses, such as cellulose or chitin. While most studies have so far mainly explored the role of LPMOs in a (plant) biomass conversion context, alternative roles and paradigms begin to emerge. In the present review, we propose a historical perspective of LPMO research providing a succinct overview of the major achievements of LPMO research over the past decade. This journey through LPMOs landscape leads us to dive into the emerging biological functions of LPMOs and LPMO-like proteins. We notably highlight roles in fungal and oomycete plant pathogenesis (e.g. potato late blight), but also in mutualistic/commensalism symbiosis (e.g. ectomycorrhizae). We further present the potential importance of LPMOs in other microbial pathogenesis including diseases caused by bacteria (e.g. pneumonia), fungi (e.g. human meningitis), oomycetes and viruses (e.g. entomopox), as well as in (micro)organism development (including several plant pests). Our assessment of the literature leads to the formulation of outstanding questions, promising for the coming years exciting research and discoveries on these moonlighting proteins.
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Affiliation(s)
- Theruvothu Madathil Vandhana
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad, 500046, India
| | - Jean-Lou Reyre
- INRAE, UMR1163 Biodiversité et Biotechnologie Fongiques, Aix Marseille University, 13009, Marseille, France
- IFP Energies Nouvelles, 1 et 4 avenue de Bois-Préau, 92852, Rueil-Malmaison, France
| | - Dangudubiyyam Sushmaa
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad, 500046, India
| | - Jean-Guy Berrin
- INRAE, UMR1163 Biodiversité et Biotechnologie Fongiques, Aix Marseille University, 13009, Marseille, France
| | - Bastien Bissaro
- INRAE, UMR1163 Biodiversité et Biotechnologie Fongiques, Aix Marseille University, 13009, Marseille, France
| | - Jogi Madhuprakash
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Gachibowli, Hyderabad, 500046, India
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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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Kuusk S, Väljamäe P. Kinetics of H 2O 2-driven catalysis by a lytic polysaccharide monooxygenase from the fungus Trichoderma reesei. J Biol Chem 2021; 297:101256. [PMID: 34597668 PMCID: PMC8528726 DOI: 10.1016/j.jbc.2021.101256] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 09/24/2021] [Accepted: 09/25/2021] [Indexed: 01/17/2023] Open
Abstract
Owing to their ability to break glycosidic bonds in recalcitrant crystalline polysaccharides such as cellulose, the catalysis effected by lytic polysaccharide monooxygenases (LPMOs) is of major interest. Kinetics of these reductant-dependent, monocopper enzymes is complicated by the insoluble nature of the cellulose substrate and parallel, enzyme-dependent, and enzyme-independent side reactions between the reductant and oxygen-containing cosubstrates. Here, we provide kinetic characterization of cellulose peroxygenase (oxidative cleavage of glycosidic bonds in cellulose) and reductant peroxidase (oxidation of the reductant) activities of the LPMO TrAA9A of the cellulose-degrading model fungus Trichoderma reesei. The catalytic efficiency (kcat/Km(H2O2)) of the cellulose peroxygenase reaction (kcat = 8.5 s−1, and Km(H2O2)=30μM) was an order of magnitude higher than that of the reductant (ascorbic acid) peroxidase reaction. The turnover of H2O2 in the ascorbic acid peroxidase reaction followed the ping-pong mechanism and led to irreversible inactivation of the enzyme with a probability of 0.0072. Using theoretical analysis, we suggest a relationship between the half-life of LPMO, the values of kinetic parameters, and the concentrations of the reactants.
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Affiliation(s)
- Silja Kuusk
- Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Priit Väljamäe
- Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia.
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Thermostable cellulose saccharifying microbial enzymes: Characteristics, recent advances and biotechnological applications. Int J Biol Macromol 2021; 188:226-244. [PMID: 34371052 DOI: 10.1016/j.ijbiomac.2021.08.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/19/2021] [Accepted: 08/03/2021] [Indexed: 12/12/2022]
Abstract
Cellulases play a promising role in the bioconversion of renewable lignocellulosic biomass into fermentable sugars which are subsequently fermented to biofuels and other value-added chemicals. Besides biofuel industries, they are also in huge demand in textile, detergent, and paper and pulp industries. Low titres of cellulase production and processing are the main issues that contribute to high enzyme cost. The success of ethanol-based biorefinery depends on high production titres and the catalytic efficiency of cellulases functional at elevated temperatures with acid/alkali tolerance and the low cost. In view of their wider application in various industrial processes, stable cellulases that are active at elevated temperatures in the acidic-alkaline pH ranges, and organic solvents and salt tolerance would be useful. This review provides a recent update on the advances made in thermostable cellulases. Developments in their sources, characteristics and mechanisms are updated. Various methods such as rational design, directed evolution, synthetic & system biology and immobilization techniques adopted in evolving cellulases with ameliorated thermostability and characteristics are also discussed. The wide range of applications of thermostable cellulases in various industrial sectors is described.
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Calderaro F, Bevers LE, van den Berg MA. Oxidative Power: Tools for Assessing LPMO Activity on Cellulose. Biomolecules 2021; 11:biom11081098. [PMID: 34439765 PMCID: PMC8391687 DOI: 10.3390/biom11081098] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 07/19/2021] [Accepted: 07/22/2021] [Indexed: 01/22/2023] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) have sparked a lot of research regarding their fascinating mode-of-action. Particularly, their boosting effect on top of the well-known cellulolytic enzymes in lignocellulosic hydrolysis makes them industrially relevant targets. As more characteristics of LPMO and its key role have been elucidated, the need for fast and reliable methods to assess its activity have become clear. Several aspects such as its co-substrates, electron donors, inhibiting factors, and the inhomogeneity of lignocellulose had to be considered during experimental design and data interpretation, as they can impact and often hamper outcomes. This review provides an overview of the currently available methods to measure LPMO activity, including their potential and limitations, and it is illustrated with practical examples.
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Affiliation(s)
- Federica Calderaro
- DSM Biotechnology Center, 2613 AX Delft, The Netherlands; (L.E.B.); (M.A.v.d.B.)
- Molecular Enzymolog y Group, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
- Correspondence: ; Tel.: +31-6-36028569
| | - Loes E. Bevers
- DSM Biotechnology Center, 2613 AX Delft, The Netherlands; (L.E.B.); (M.A.v.d.B.)
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Sethupathy S, Morales GM, Li Y, Wang Y, Jiang J, Sun J, Zhu D. Harnessing microbial wealth for lignocellulose biomass valorization through secretomics: a review. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:154. [PMID: 34225772 PMCID: PMC8256616 DOI: 10.1186/s13068-021-02006-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 06/26/2021] [Indexed: 05/10/2023]
Abstract
The recalcitrance of lignocellulosic biomass is a major constraint to its high-value use at industrial scale. In nature, microbes play a crucial role in biomass degradation, nutrient recycling and ecosystem functioning. Therefore, the use of microbes is an attractive way to transform biomass to produce clean energy and high-value compounds. The microbial degradation of lignocelluloses is a complex process which is dependent upon multiple secreted enzymes and their synergistic activities. The availability of the cutting edge proteomics and highly sensitive mass spectrometry tools make possible for researchers to probe the secretome of microbes and microbial consortia grown on different lignocelluloses for the identification of hydrolytic enzymes of industrial interest and their substrate-dependent expression. This review summarizes the role of secretomics in identifying enzymes involved in lignocelluloses deconstruction, the development of enzyme cocktails and the construction of synthetic microbial consortia for biomass valorization, providing our perspectives to address the current challenges.
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Affiliation(s)
- Sivasamy Sethupathy
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Gabriel Murillo Morales
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Yixuan Li
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Yongli Wang
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Jianxiong Jiang
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Jianzhong Sun
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Daochen Zhu
- School of the Environment and Safety Engineering, Biofuels Institute, Jiangsu University, Zhenjiang, 212013, Jiangsu, China.
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Manavalan T, Stepnov AA, Hegnar OA, Eijsink VGH. Sugar oxidoreductases and LPMOs - two sides of the same polysaccharide degradation story? Carbohydr Res 2021; 505:108350. [PMID: 34049079 DOI: 10.1016/j.carres.2021.108350] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 05/13/2021] [Accepted: 05/14/2021] [Indexed: 12/20/2022]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) catalyze the oxidative cleavage of glycosidic bonds in recalcitrant polysaccharides such as chitin and cellulose and their discovery has revolutionized our understanding of enzymatic biomass conversion. The discovery of LPMOs raises interesting new questions regarding the roles of other oxidoreductases and abiotic redox processes in biomass conversion. LPMOs need reducing power and an oxygen co-substrate and biomass degrading ecosystems contain a multitude of redox enzymes that affect the availability of both. For example, biomass degrading fungi produce multiple sugar oxidoreductases whose biological functions so far have remained somewhat enigmatic. It is now conceivable that these redox enzymes, in particular H2O2-producing sugar oxidases, could play a role in fueling and controlling LPMO reactions. Here, we shortly review contemporary issues in the LPMO field, paying particular attention to the possible roles of sugar oxidoreductases.
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Affiliation(s)
- Tamilvendan Manavalan
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Science, N-1432, Ås, Norway
| | - Anton A Stepnov
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Science, N-1432, Ås, Norway
| | - Olav A Hegnar
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Science, N-1432, Ås, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, NMBU - Norwegian University of Life Science, N-1432, Ås, Norway.
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Zarattini M, Corso M, Kadowaki MA, Monclaro A, Magri S, Milanese I, Jolivet S, de Godoy MO, Hermans C, Fagard M, Cannella D. LPMO-oxidized cellulose oligosaccharides evoke immunity in Arabidopsis conferring resistance towards necrotrophic fungus B. cinerea. Commun Biol 2021; 4:727. [PMID: 34117349 PMCID: PMC8196058 DOI: 10.1038/s42003-021-02226-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 05/12/2021] [Indexed: 12/13/2022] Open
Abstract
Lytic Polysaccharide Monooxygenases (LPMOs) are powerful redox enzymes able to oxidatively cleave recalcitrant polysaccharides. Widely conserved across biological kingdoms, LPMOs of the AA9 family are deployed by phytopathogens to deconstruct cellulose polymers. In response, plants have evolved sophisticated mechanisms to sense cell wall damage and thus self-triggering Damage Triggered Immunity responses. Here, we show that Arabidopsis plants exposed to LPMO products triggered the innate immunity ultimately leading to increased resistance to the necrotrophic fungus Botrytis cinerea. We demonstrated that plants undergo a deep transcriptional reprogramming upon elicitation with AA9 derived cellulose- or cello-oligosaccharides (AA9_COS). To decipher the specific effects of native and oxidized LPMO-generated AA9_COS, a pairwise comparison with cellobiose, the smallest non-oxidized unit constituting cellulose, is presented. Moreover, we identified two leucine-rich repeat receptor-like kinases, namely STRESS INDUCED FACTOR 2 and 4, playing a crucial role in signaling the AA9_COS-dependent responses such as camalexin production. Furthermore, increased levels of ethylene, jasmonic and salicylic acid hormones, along with deposition of callose in the cell wall was observed. Collectively, our data reveal that LPMOs might play a crucial role in plant-pathogen interactions. Zarattini et al. confirm the capacity of Lytic Polysaccharide Monooxygenases (LPMO) active on cellulose to trigger immune responses in Arabidopsis. These results bring insight to the field of cell wall modifying enzymes and their roles in plant defense mechanisms.
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Affiliation(s)
- Marco Zarattini
- PhotoBioCatalysis Unit-BioCat, Crop Production and Biostimulation Laboratory CPBL and BTL, Université libre de Bruxelles, Brussels, Belgium
| | - Massimiliano Corso
- Institut Jean-Pierre Bourgin, Université Paris-Saclay, INRAE, AgroParisTech, Versailles, France
| | - Marco Antonio Kadowaki
- PhotoBioCatalysis Unit-BioCat, Crop Production and Biostimulation Laboratory CPBL and BTL, Université libre de Bruxelles, Brussels, Belgium
| | - Antonielle Monclaro
- PhotoBioCatalysis Unit-BioCat, Crop Production and Biostimulation Laboratory CPBL and BTL, Université libre de Bruxelles, Brussels, Belgium
| | - Silvia Magri
- PhotoBioCatalysis Unit-BioCat, Crop Production and Biostimulation Laboratory CPBL and BTL, Université libre de Bruxelles, Brussels, Belgium
| | - Irma Milanese
- PhotoBioCatalysis Unit-BioCat, Crop Production and Biostimulation Laboratory CPBL and BTL, Université libre de Bruxelles, Brussels, Belgium
| | - Sylvie Jolivet
- Institut Jean-Pierre Bourgin, Université Paris-Saclay, INRAE, AgroParisTech, Versailles, France
| | - Mariana Ortiz de Godoy
- PhotoBioCatalysis Unit-BioCat, Crop Production and Biostimulation Laboratory CPBL and BTL, Université libre de Bruxelles, Brussels, Belgium
| | - Christian Hermans
- Crop Production and Biostimulation Laboratory, Université libre de Bruxelles, Brussels, Belgium
| | - Mathilde Fagard
- Institut Jean-Pierre Bourgin, Université Paris-Saclay, INRAE, AgroParisTech, Versailles, France
| | - David Cannella
- PhotoBioCatalysis Unit-BioCat, Crop Production and Biostimulation Laboratory CPBL and BTL, Université libre de Bruxelles, Brussels, Belgium.
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Mekasha S, Tuveng TR, Vaaje-Kolstad G, Eijsink VGH. Chromatographic Assays for the Enzymatic Degradation of Chitin. Bio Protoc 2021; 11:e4014. [PMID: 34124313 DOI: 10.21769/bioprotoc.4014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 02/28/2021] [Accepted: 03/03/2021] [Indexed: 01/14/2023] Open
Abstract
Chitin is an insoluble linear polymer of β(1→4)-linked N-acetylglucosamine. Enzymatic cleavage of chitin chains can be achieved using hydrolytic enzymes, called chitinases, and/or oxidative enzymes, called lytic polysaccharide monooxygenases (LPMOs). These two groups of enzymes have different modes of action and yield different product types that require different analytical methods for detection and quantitation. While soluble chromogenic substrates are readily available for chitinases, proper insight into the activity of these enzymes can only be obtained by measuring activity toward their polymeric, insoluble substrate, chitin. For LPMOs, only assays using insoluble chitin are possible and relevant. Working with insoluble substrates complicates enzyme assays from substrate preparation to product analysis. Here, we describe typical set-ups for chitin degradation reactions and the chromatographic methods used for product analysis. Graphical abstract: Overview of chromatographic methods for assessing the enzymatic degradation of chitin.
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Affiliation(s)
- Sophanit Mekasha
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Tina R Tuveng
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Gustav Vaaje-Kolstad
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
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Discovery of fungal oligosaccharide-oxidising flavo-enzymes with previously unknown substrates, redox-activity profiles and interplay with LPMOs. Nat Commun 2021; 12:2132. [PMID: 33837197 PMCID: PMC8035211 DOI: 10.1038/s41467-021-22372-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 03/09/2021] [Indexed: 12/14/2022] Open
Abstract
Oxidative plant cell-wall processing enzymes are of great importance in biology and biotechnology. Yet, our insight into the functional interplay amongst such oxidative enzymes remains limited. Here, a phylogenetic analysis of the auxiliary activity 7 family (AA7), currently harbouring oligosaccharide flavo-oxidases, reveals a striking abundance of AA7-genes in phytopathogenic fungi and Oomycetes. Expression of five fungal enzymes, including three from unexplored clades, expands the AA7-substrate range and unveils a cellooligosaccharide dehydrogenase activity, previously unknown within AA7. Sequence and structural analyses identify unique signatures distinguishing the strict dehydrogenase clade from canonical AA7 oxidases. The discovered dehydrogenase directly is able to transfer electrons to an AA9 lytic polysaccharide monooxygenase (LPMO) and fuel cellulose degradation by LPMOs without exogenous reductants. The expansion of redox-profiles and substrate range highlights the functional diversity within AA7 and sets the stage for harnessing AA7 dehydrogenases to fine-tune LPMO activity in biotechnological conversion of plant feedstocks. Microbial oxidoreductases are key in biomass breakdown. Here, the authors expand the specificity and redox scope within fungal auxiliary activity 7 family (AA7) enzymes and show that AA7 oligosaccharide dehydrogenases can directly fuel cellulose degradation by lytic polysaccharide monooxygenases.
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Stepnov AA, Forsberg Z, Sørlie M, Nguyen GS, Wentzel A, Røhr ÅK, Eijsink VGH. Unraveling the roles of the reductant and free copper ions in LPMO kinetics. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:28. [PMID: 33478537 PMCID: PMC7818938 DOI: 10.1186/s13068-021-01879-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Accepted: 01/07/2021] [Indexed: 05/02/2023]
Abstract
BACKGROUND Lytic polysaccharide monooxygenases (LPMOs) are monocopper enzymes that catalyze oxidative depolymerization of industrially relevant crystalline polysaccharides, such as cellulose, in a reaction that depends on an electron donor and O2 or H2O2. While it is well known that LPMOs can utilize a wide variety of electron donors, the variation in reported efficiencies of various LPMO-reductant combinations remains largely unexplained. RESULTS In this study, we describe a novel two-domain cellulose-active family AA10 LPMO from a marine actinomycete, which we have used to look more closely at the effects of the reductant and copper ions on the LPMO reaction. Our results show that ascorbate-driven LPMO reactions are extremely sensitive to very low amounts (micromolar concentrations) of free copper because reduction of free Cu(II) ions by ascorbic acid leads to formation of H2O2, which speeds up the LPMO reaction. In contrast, the use of gallic acid yields steady reactions that are almost insensitive to the presence of free copper ions. Various experiments, including dose-response studies with the enzyme, showed that under typically used reaction conditions, the rate of the reaction is limited by LPMO-independent formation of H2O2 resulting from oxidation of the reductant. CONCLUSION The strong impact of low amounts of free copper on LPMO reactions with ascorbic acid and O2, i.e. the most commonly used conditions when assessing LPMO activity, likely explains reported variations in LPMO rates. The observed differences between ascorbic acid and gallic acid show a way of making LPMO reactions less copper-dependent and illustrate that reductant effects on LPMO action need to be interpreted with great caution. In clean reactions, with minimized generation of H2O2, the (O2-driven) LPMO reaction is exceedingly slow, compared to the much faster peroxygenase reaction that occurs when adding H2O2.
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Affiliation(s)
- Anton A Stepnov
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Ås, Norway
| | - Zarah Forsberg
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Ås, Norway
| | - Morten Sørlie
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Ås, Norway
| | - Giang-Son Nguyen
- Department of Biotechnology and Nanomedicine, SINTEF Industry, Trondheim, Norway
| | - Alexander Wentzel
- Department of Biotechnology and Nanomedicine, SINTEF Industry, Trondheim, Norway
| | - Åsmund K Røhr
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Ås, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Ås, Norway.
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Bernardi AV, Gerolamo LE, de Gouvêa PF, Yonamine DK, Pereira LMS, de Oliveira AHC, Uyemura SA, Dinamarco TM. LPMO AfAA9_B and Cellobiohydrolase AfCel6A from A. fumigatus Boost Enzymatic Saccharification Activity of Cellulase Cocktail. Int J Mol Sci 2020; 22:E276. [PMID: 33383972 PMCID: PMC7795096 DOI: 10.3390/ijms22010276] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 12/21/2020] [Accepted: 12/24/2020] [Indexed: 01/02/2023] Open
Abstract
Cellulose is the most abundant polysaccharide in lignocellulosic biomass, where it is interlinked with lignin and hemicellulose. Bioethanol can be produced from biomass. Since breaking down biomass is difficult, cellulose-active enzymes secreted by filamentous fungi play an important role in degrading recalcitrant lignocellulosic biomass. We characterized a cellobiohydrolase (AfCel6A) and lytic polysaccharide monooxygenase LPMO (AfAA9_B) from Aspergillus fumigatus after they were expressed in Pichia pastoris and purified. The biochemical parameters suggested that the enzymes were stable; the optimal temperature was ~60 °C. Further characterization revealed high turnover numbers (kcat of 147.9 s-1 and 0.64 s-1, respectively). Surprisingly, when combined, AfCel6A and AfAA9_B did not act synergistically. AfCel6A and AfAA9_B association inhibited AfCel6A activity, an outcome that needs to be further investigated. However, AfCel6A or AfAA9_B addition boosted the enzymatic saccharification activity of a cellulase cocktail and the activity of cellulase Af-EGL7. Enzymatic cocktail supplementation with AfCel6A or AfAA9_B boosted the yield of fermentable sugars from complex substrates, especially sugarcane exploded bagasse, by up to 95%. The synergism between the cellulase cocktail and AfAA9_B was enzyme- and substrate-specific, which suggests a specific enzymatic cocktail for each biomass by up to 95%. The synergism between the cellulase cocktail and AfAA9_B was enzyme- and substrate-specific, which suggests a specific enzymatic cocktail for each biomass.
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Affiliation(s)
- Aline Vianna Bernardi
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, Brazil; (A.V.B.); (L.E.G.); (P.F.d.G.); (D.K.Y.); (L.M.S.P.); (A.H.C.d.O.)
| | - Luis Eduardo Gerolamo
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, Brazil; (A.V.B.); (L.E.G.); (P.F.d.G.); (D.K.Y.); (L.M.S.P.); (A.H.C.d.O.)
| | - Paula Fagundes de Gouvêa
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, Brazil; (A.V.B.); (L.E.G.); (P.F.d.G.); (D.K.Y.); (L.M.S.P.); (A.H.C.d.O.)
| | - Deborah Kimie Yonamine
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, Brazil; (A.V.B.); (L.E.G.); (P.F.d.G.); (D.K.Y.); (L.M.S.P.); (A.H.C.d.O.)
| | - Lucas Matheus Soares Pereira
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, Brazil; (A.V.B.); (L.E.G.); (P.F.d.G.); (D.K.Y.); (L.M.S.P.); (A.H.C.d.O.)
| | - Arthur Henrique Cavalcante de Oliveira
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, Brazil; (A.V.B.); (L.E.G.); (P.F.d.G.); (D.K.Y.); (L.M.S.P.); (A.H.C.d.O.)
| | - Sérgio Akira Uyemura
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-903, Brazil;
| | - Taisa Magnani Dinamarco
- Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-901, Brazil; (A.V.B.); (L.E.G.); (P.F.d.G.); (D.K.Y.); (L.M.S.P.); (A.H.C.d.O.)
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40
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Tuveng TR, Jensen MS, Fredriksen L, Vaaje-Kolstad G, Eijsink VGH, Forsberg Z. A thermostable bacterial lytic polysaccharide monooxygenase with high operational stability in a wide temperature range. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:194. [PMID: 33292445 PMCID: PMC7708162 DOI: 10.1186/s13068-020-01834-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 11/16/2020] [Indexed: 06/12/2023]
Abstract
BACKGROUND Lytic polysaccharide monooxygenases (LPMOs) are oxidative, copper-dependent enzymes that function as powerful tools in the turnover of various biomasses, including lignocellulosic plant biomass. While LPMOs are considered to be of great importance for biorefineries, little is known about industrial relevant properties such as the ability to operate at high temperatures. Here, we describe a thermostable, cellulose-active LPMO from a high-temperature compost metagenome (called mgLPMO10). RESULTS MgLPMO10 was found to have the highest apparent melting temperature (83 °C) reported for an LPMO to date, and is catalytically active up to temperatures of at least 80 °C. Generally, mgLPMO10 showed good activity and operational stability over a wide temperature range. The LPMO boosted cellulose saccharification by recombinantly produced GH48 and GH6 cellobiohydrolases derived from the same metagenome, albeit to a minor extent. Cellulose saccharification studies with a commercial cellulase cocktail (Celluclast®) showed that the performance of this thermostable bacterial LPMO is comparable with that of a frequently utilized fungal LPMO from Thermoascus aurantiacus (TaLPMO9A). CONCLUSIONS The high activity and operational stability of mgLPMO10 are of both fundamental and applied interest. The ability of mgLPMO10 to perform oxidative cleavage of cellulose at 80 °C and the clear synergy with Celluclast® make this enzyme an interesting candidate in the development of thermostable enzyme cocktails for use in lignocellulosic biorefineries.
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Affiliation(s)
- Tina Rise Tuveng
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Aas, Norway
| | - Marianne Slang Jensen
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Aas, Norway
| | - Lasse Fredriksen
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Aas, Norway
| | - Gustav Vaaje-Kolstad
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Aas, Norway
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Aas, Norway.
| | - Zarah Forsberg
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Aas, Norway.
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Dodge N, Russo DA, Blossom BM, Singh RK, van Oort B, Croce R, Bjerrum MJ, Jensen PE. Water-soluble chlorophyll-binding proteins from Brassica oleracea allow for stable photobiocatalytic oxidation of cellulose by a lytic polysaccharide monooxygenase. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:192. [PMID: 33292428 PMCID: PMC7708235 DOI: 10.1186/s13068-020-01832-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 11/16/2020] [Indexed: 05/06/2023]
Abstract
BACKGROUND Lytic polysaccharide monooxygenases (LPMOs) are indispensable redox enzymes used in industry for the saccharification of plant biomass. LPMO-driven cellulose oxidation can be enhanced considerably through photobiocatalysis using chlorophyll derivatives and light. Water soluble chlorophyll binding proteins (WSCPs) make it is possible to stabilize and solubilize chlorophyll in aqueous solution, allowing for in vitro studies on photostability and ROS production. Here we aim to apply WSCP-Chl a as a photosensitizing complex for photobiocatalysis with the LPMO, TtAA9. RESULTS We have in this study demonstrated how WSCP reconstituted with chlorophyll a (WSCP-Chl a) can create a stable photosensitizing complex which produces controlled amounts of H2O2 in the presence of ascorbic acid and light. WSCP-Chl a is highly reactive and allows for tightly controlled formation of H2O2 by regulating light intensity. TtAA9 together with WSCP-Chl a shows increased cellulose oxidation under low light conditions, and the WSCP-Chl a complex remains stable after 24 h of light exposure. Additionally, the WSCP-Chl a complex demonstrates stability over a range of temperatures and pH conditions relevant for enzyme activity in industrial settings. CONCLUSION With WSCP-Chl a as the photosensitizer, the need to replenish Chl is greatly reduced, enhancing the catalytic lifetime of light-driven LPMOs and increasing the efficiency of cellulose depolymerization. WSCP-Chl a allows for stable photobiocatalysis providing a sustainable solution for biomass processing.
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Affiliation(s)
- N Dodge
- Department of Food Science, University of Copenhagen, Rolighedsvej 26, 1958, Frederiksberg, Denmark
| | - D A Russo
- Department of Bioorganic Analytics, Institute for Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, Jena, Germany
| | - B M Blossom
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg C, Denmark
| | - R K Singh
- Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - B van Oort
- Biophysics of Photosynthesis, Department of Physics and Astronomy, Faculty of Sciences, and LaserLaB Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - R Croce
- Biophysics of Photosynthesis, Department of Physics and Astronomy, Faculty of Sciences, and LaserLaB Amsterdam, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - M J Bjerrum
- Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - P E Jensen
- Department of Food Science, University of Copenhagen, Rolighedsvej 26, 1958, Frederiksberg, Denmark.
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42
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Kont R, Bissaro B, Eijsink VGH, Väljamäe P. Kinetic insights into the peroxygenase activity of cellulose-active lytic polysaccharide monooxygenases (LPMOs). Nat Commun 2020; 11:5786. [PMID: 33188177 PMCID: PMC7666214 DOI: 10.1038/s41467-020-19561-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 10/13/2020] [Indexed: 01/06/2023] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are widely distributed in Nature, where they catalyze the hydroxylation of glycosidic bonds in polysaccharides. Despite the importance of LPMOs in the global carbon cycle and in industrial biomass conversion, the catalytic properties of these monocopper enzymes remain enigmatic. Strikingly, there is a remarkable lack of kinetic data, likely due to a multitude of experimental challenges related to the insoluble nature of LPMO substrates, like cellulose and chitin, and to the occurrence of multiple side reactions. Here, we employed competition between well characterized reference enzymes and LPMOs for the H2O2 co-substrate to kinetically characterize LPMO-catalyzed cellulose oxidation. LPMOs of both bacterial and fungal origin showed high peroxygenase efficiencies, with kcat/KmH2O2 values in the order of 105-106 M-1 s-1. Besides providing crucial insight into the cellulolytic peroxygenase reaction, these results show that LPMOs belonging to multiple families and active on multiple substrates are true peroxygenases.
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Affiliation(s)
- Riin Kont
- Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia
| | - Bastien Bissaro
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Ås, Norway.,INRAE, Aix Marseille University, UMR1163 Biodiversité et Biotechnologie Fongiques, 13009, Marseille, France
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, NMBU-Norwegian University of Life Sciences, Ås, Norway
| | - Priit Väljamäe
- Institute of Molecular and Cell Biology, University of Tartu, Tartu, Estonia.
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A fast and easy strategy for lytic polysaccharide monooxygenase-cleavable His 6-Tag cloning, expression, and purification. Enzyme Microb Technol 2020; 143:109704. [PMID: 33375972 DOI: 10.1016/j.enzmictec.2020.109704] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 11/02/2020] [Accepted: 11/05/2020] [Indexed: 11/22/2022]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are industrially important enzymes able to enhance the enzymatic lignocellulose saccharification in synergism with classical glycoside hydrolases. Fungal LPMOs have been classified as AA9, AA11, and AA13-16 families showing a diverse specificity for substrates such as soluble and insoluble beta-glucans, chitin, starch, and xylan, besides cellulose. These enzymes are still not fully characterized, and for example this is testify by their mechanism of oxidation regularly reviewed multiple times in the last decade. Noteworthy is that despite the extremely large abundance in the entire Tree of Life, our structural and functional knowledge is based on a restricted pool of LPMO, and probably one of the main reason reside in the challenging posed by their heterologous expression. Notably, the lack of a simple cloning protocol that could be universally applied to LPMO, hinders the conversion of the ever-increasing available genomic information to actual new enzymes. Here, we provide an easy and fast protocol for cloning, expression, and purification of active LPMOs in the following architecture: natural signal peptide, LPMO enzyme, TEV protease site, and His6-Tag. For this purpose, a commercial methanol inducible expression vector was initially modified to allow the LPMO expression containing the above characteristics. Gibson assembly, a one-step isothermal DNA assembly, was adopted for the direct assembly of intron-less or intron-containing genes and the modified expression vector. Moreover, His6-tagged LPMO constructs can be submitted to TEV proteolysis for removal of the questionable C-terminal His6-Tag, obtaining a close-to-native form of LPMO. We successfully applied this method to clone, express, and purify six LPMOs from AA9 family with different regioselectivities. The proposed protocol, provided as step-by-step, could be virtually applied in many laboratories thanks to the choice of popular and commons materials.
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