1
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Zhang X, Chen K, Long L, Ding S. Two C1-oxidizing AA9 lytic polysaccharide monooxygenases from Sordaria brevicollis differ in thermostability, activity, and synergy with cellulase. Appl Microbiol Biotechnol 2021; 105:8739-8759. [PMID: 34748039 DOI: 10.1007/s00253-021-11677-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 10/26/2021] [Accepted: 10/28/2021] [Indexed: 11/24/2022]
Abstract
Cellulolytic fungi usually have multiple genes for C1-oxidizing auxiliary activity 9 (AA9) lytic polysaccharide monooxygenases (LPMOs) in their genomes, but their potential functional differences are less understood. In this study, two C1-oxidizing AA9 LPMOs, SbLPMO9A and SbLPMO9B, were identified from Sordaria brevicollis, and their differences, particularly in terms of thermostability, reducing agent specificity, and synergy with cellulase, were explored. The two enzymes exhibited weak binding to cellulose and intolerance to hydrogen peroxide. Their oxidative activity was influenced by cellulose crystallinity and surface morphology, and both enzymes tended to oxidize celluloses of lower crystallinity and high surface area. Comparably, SbLPMO9A had much better thermostability than SbLPMO9B, which may be attributed to the presence of a carbohydrate binding module 1 (CBM1)-like sequence at its C-terminus. In addition, the two enzymes exhibited different specificities and responsivities toward electron donors. SbLPMO9A and SbLPMO9B were able to boost the catalytic efficiency of endoglucanase I (EGI) on physically and chemically pretreated substrates but with different degrees of synergy. Substrate- and enzyme-specific synergism was observed by comparing the synergistic action of SbLPMO9A or SbLPMO9B with commercial Celluclast 1.5L on three kinds of cellulosic substrates. On regenerated amorphous cellulose and PFI (Papirindustriens Forskningsinstitut)-fibrillated bleached eucalyptus pulp, SbLPMO9B showed a higher synergistic effect than SbLPMO9A, while on delignified wheat straw, the synergistic effect of SbLPMO9A was higher than that of SbLPMO9B. On account of its excellent thermostability and boosting effect on the enzymatic hydrolysis of delignified wheat straw, SbLPMO9A may have high application potential in biorefineries for lignocellulosic biomass. KEY POINTS: • C1-oxidizing SbLPMO9A displayed higher thermostability than SbLPMO9B, probably due to the presence of a CBM1-like module. • The oxidative activity of the two SbLPMO9s on celluloses increased with decreasing cellulose crystallinity or increasing beating degree. • The two SbLPMO9s boosted the catalytic efficiency of cellulase, but the synergistic effect was substrate- and enzyme-specific.
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Affiliation(s)
- Xi Zhang
- The Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Key Lab for the Chemistry & Utilization of Agricultural and Forest Biomass, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Kaixiang Chen
- The Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Key Lab for the Chemistry & Utilization of Agricultural and Forest Biomass, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Liangkun Long
- The Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Key Lab for the Chemistry & Utilization of Agricultural and Forest Biomass, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China
| | - Shaojun Ding
- The Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources, Jiangsu Key Lab for the Chemistry & Utilization of Agricultural and Forest Biomass, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, Jiangsu, China.
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2
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Jagadeeswaran G, Veale L, Mort AJ. Do Lytic Polysaccharide Monooxygenases Aid in Plant Pathogenesis and Herbivory? TRENDS IN PLANT SCIENCE 2021; 26:142-155. [PMID: 33097402 DOI: 10.1016/j.tplants.2020.09.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 09/07/2020] [Accepted: 09/25/2020] [Indexed: 06/11/2023]
Abstract
Lytic polysaccharide monooxygenases (LPMOs), copper-dependent enzymes mainly found in fungi, bacteria, and viruses, are responsible for enabling plant infection and degradation processes. Since their discovery 10 years ago, significant progress has been made in understanding the major role these enzymes play in biomass conversion. The recent discovery of additional LPMO families in fungi and oomycetes (AA16) as well as insects (AA15) strongly suggests that LPMOs might also be involved in biological processes such as overcoming plant defenses. In this review, we aim to give a comprehensive overview of the potential role of different LPMO families from the perspective of plant defense and their multiple implications in devising new strategies for achieving crop protection from plant pathogens and insect pests.
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Affiliation(s)
- Guru Jagadeeswaran
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Lawrie Veale
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Andrew J Mort
- Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK, 74078, USA.
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3
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Gaber Y, Rashad B, Hussein R, Abdelgawad M, Ali NS, Dishisha T, Várnai A. Heterologous expression of lytic polysaccharide monooxygenases (LPMOs). Biotechnol Adv 2020; 43:107583. [DOI: 10.1016/j.biotechadv.2020.107583] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 06/19/2020] [Accepted: 06/20/2020] [Indexed: 12/20/2022]
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4
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Singh RK, Blossom BM, Russo DA, Singh R, Weihe H, Andersen NH, Tiwari MK, Jensen PE, Felby C, Bjerrum MJ. Detection and Characterization of a Novel Copper-Dependent Intermediate in a Lytic Polysaccharide Monooxygenase. Chemistry 2019; 26:454-463. [PMID: 31603264 DOI: 10.1002/chem.201903562] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 10/08/2019] [Indexed: 01/27/2023]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are copper-containing enzymes capable of oxidizing crystalline cellulose which have large practical application in the process of refining biomass. The catalytic mechanism of LPMOs still remains debated despite several proposed reaction mechanisms. Here, we report a long-lived intermediate (t1/2 =6-8 minutes) observed in an LPMO from Thermoascus aurantiacus (TaLPMO9A). The intermediate with a strong absorption around 420 nm is formed when reduced LPMO-CuI reacts with sub-equimolar amounts of H2 O2 . UV/Vis absorption spectroscopy, electron paramagnetic resonance, resonance Raman and stopped-flow spectroscopy suggest that the observed long-lived intermediate involves the copper center and a nearby tyrosine (Tyr175). Additionally, activity assays in the presence of sub-equimolar amounts of H2 O2 showed an increase in the LPMO oxidation of phosphoric acid swollen cellulose. Accordingly, this suggests that the long-lived copper-dependent intermediate could be part of the catalytic mechanism for LPMOs. The observed intermediate offers a new perspective into the oxidative reaction mechanism of TaLPMO9A and hence for the biomass oxidation and the reactivity of copper in biological systems.
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Affiliation(s)
- Raushan K Singh
- Department of Chemistry, University of Copenhagen, DK-2100, Copenhagen, Denmark
| | - Benedikt M Blossom
- Department of Geosciences and Natural Resource Management, University of Copenhagen, DK-1958, Frederiksberg C, Denmark
| | - David A Russo
- Department of Plant and Environmental Sciences, University of Copenhagen, DK-1958, Frederiksberg C, Denmark
- Current address: Institute for Inorganic and Analytical Chemistry, Friedrich Schiller University Jena, 07743, Jena, Germany
| | - Ranjitha Singh
- Department of Chemistry, University of Copenhagen, DK-2100, Copenhagen, Denmark
| | - Høgni Weihe
- Department of Chemistry, University of Copenhagen, DK-2100, Copenhagen, Denmark
| | | | - Manish K Tiwari
- Department of Chemistry, University of Copenhagen, DK-2100, Copenhagen, Denmark
| | - Poul E Jensen
- Department of Plant and Environmental Sciences, University of Copenhagen, DK-1958, Frederiksberg C, Denmark
| | - Claus Felby
- Department of Geosciences and Natural Resource Management, University of Copenhagen, DK-1958, Frederiksberg C, Denmark
| | - Morten J Bjerrum
- Department of Chemistry, University of Copenhagen, DK-2100, Copenhagen, Denmark
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5
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Frandsen KEH, Tovborg M, Jørgensen CI, Spodsberg N, Rosso MN, Hemsworth GR, Garman EF, Grime GW, Poulsen JCN, Batth TS, Miyauchi S, Lipzen A, Daum C, Grigoriev IV, Johansen KS, Henrissat B, Berrin JG, Lo Leggio L. Insights into an unusual Auxiliary Activity 9 family member lacking the histidine brace motif of lytic polysaccharide monooxygenases. J Biol Chem 2019; 294:17117-17130. [PMID: 31471321 DOI: 10.1074/jbc.ra119.009223] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 08/22/2019] [Indexed: 01/13/2023] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are redox-enzymes involved in biomass degradation. All characterized LPMOs possess an active site of two highly conserved histidine residues coordinating a copper ion (the histidine brace), which are essential for LPMO activity. However, some protein sequences that belong to the AA9 LPMO family display a natural N-terminal His to Arg substitution (Arg-AA9). These are found almost entirely in the phylogenetic fungal class Agaricomycetes, associated with wood decay, but no function has been demonstrated for any Arg-AA9. Through bioinformatics, transcriptomic, and proteomic analyses we present data, which suggest that Arg-AA9 proteins could have a hitherto unidentified role in fungal degradation of lignocellulosic biomass in conjunction with other secreted fungal enzymes. We present the first structure of an Arg-AA9, LsAA9B, a naturally occurring protein from Lentinus similis The LsAA9B structure reveals gross changes in the region equivalent to the canonical LPMO copper-binding site, whereas features implicated in carbohydrate binding in AA9 LPMOs have been maintained. We obtained a structure of LsAA9B with xylotetraose bound on the surface of the protein although with a considerably different binding mode compared with other AA9 complex structures. In addition, we have found indications of protein phosphorylation near the N-terminal Arg and the carbohydrate-binding site, for which the potential function is currently unknown. Our results are strong evidence that Arg-AA9s function markedly different from canonical AA9 LPMO, but nonetheless, may play a role in fungal conversion of lignocellulosic biomass.
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Affiliation(s)
- Kristian E H Frandsen
- Department of Chemistry, University of Copenhagen, 2100 Copenhagen, Denmark.,INRA, Aix-Marseille Université, UMR1163 BBF (Biodiversité et Biotechnologie Fongiques), 13009 Marseille, France
| | | | | | | | - Marie-Noëlle Rosso
- INRA, Aix-Marseille Université, UMR1163 BBF (Biodiversité et Biotechnologie Fongiques), 13009 Marseille, France
| | - Glyn R Hemsworth
- School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom.,Department of Chemistry, University of York, York YO10 5DD, United Kingdom
| | - Elspeth F Garman
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Geoffrey W Grime
- The Ion Beam Centre, Advanced Technology Institute, University of Surrey, Guildford GU2 7XH, United Kingdom
| | | | - Tanveer S Batth
- The Novo Nordisk Foundation Center for Protein Research, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Shingo Miyauchi
- INRA, Aix-Marseille Université, UMR1163 BBF (Biodiversité et Biotechnologie Fongiques), 13009 Marseille, France
| | - Anna Lipzen
- United States Department of Energy Joint Genome Institute, Walnut Creek, California 94598
| | - Chris Daum
- United States Department of Energy Joint Genome Institute, Walnut Creek, California 94598
| | - Igor V Grigoriev
- United States Department of Energy Joint Genome Institute, Walnut Creek, California 94598.,Department of Plant and Microbial Biology, University of California Berkeley, Berkeley, California 94720
| | - Katja S Johansen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, 1958 Frederiksberg C, Denmark
| | - Bernard Henrissat
- Architecture et Fonction des Macromolécules Biologiques (AFMB), CNRS, Aix-Marseille Université, 13009 Marseille, France.,INRA, USC 1408 AFMB, 13009 Marseille, France.,Department of Biological Sciences, King Abdulaziz University, 21589 Jeddah, Saudi Arabia
| | - Jean-Guy Berrin
- INRA, Aix-Marseille Université, UMR1163 BBF (Biodiversité et Biotechnologie Fongiques), 13009 Marseille, France
| | - Leila Lo Leggio
- Department of Chemistry, University of Copenhagen, 2100 Copenhagen, Denmark
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6
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Jagadeeswaran G, Gainey L, Mort AJ. An AA9-LPMO containing a CBM1 domain in Aspergillus nidulans is active on cellulose and cleaves cello-oligosaccharides. AMB Express 2018; 8:171. [PMID: 30328527 PMCID: PMC6192940 DOI: 10.1186/s13568-018-0701-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Accepted: 10/10/2018] [Indexed: 11/14/2022] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are copper dependent enzymes that carry out oxidative cleavage of cellulose and other polysaccharides. Aspergillus nidulans, an ascomycete fungus that contains multiple AA9 LPMOs in the genome, offers an excellent model system to study their activity during the oxidative degradation of biomass. AN1602, a dual domain AA9-LPMO in A. nidulans appended with a carbohydrate-binding module, CBM1, was expressed in Pichia pastoris for analyzing oxidative cleavage on cellulosic substrates. The mass spectral and HPAEC analyses showed that the enzyme cleaves phosphoric acid swollen cellulose (PASC) in the presence of a reducing agent, yielding a range of cello-oligosaccharides. In addition to the polymeric substrate cellulose, AN1602 is also active on soluble cellohexaose, a property that is restricted to only a few characterized LPMOs. Product analysis of AN1602 cleaved cellohexaose revealed that C4 was the sole site of oxidation. The sequence and predicted structure of the catalytic domain of AN1602 matched very closely to known C4 cellohexaose active enzymes.
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7
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Urresti S, Cartmell A, Liu F, Walton PH, Davies GJ. Structural studies of the unusual metal-ion site of the GH124 endoglucanase from Ruminiclostridium thermocellum. Acta Crystallogr F Struct Biol Commun 2018; 74:496-505. [PMID: 30084399 PMCID: PMC6096483 DOI: 10.1107/s2053230x18006842] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 05/03/2018] [Indexed: 12/20/2022] Open
Abstract
The recent discovery of `lytic' polysaccharide monooxygenases, copper-dependent enzymes for biomass degradation, has provided new impetus for the analysis of unusual metal-ion sites in carbohydrate-active enzymes. In this context, the CAZY family GH124 endoglucanase from Ruminiclostridium thermocellum contains an unusual metal-ion site, which was originally modelled as a Ca2+ site but features aspartic acid, asparagine and two histidine imidazoles as coordinating residues, which are more consistent with a transition-metal binding environment. It was sought to analyse whether the GH124 metal-ion site might accommodate other metals. It is demonstrated through thermal unfolding experiments that this metal-ion site can accommodate a range of transition metals (Fe2+, Cu2+, Mn2+ and Ni2+), whilst the three-dimensional structure and mass spectrometry show that one of the histidines is partially covalently modified and is present as a 2-oxohistidine residue; a feature that is rarely observed but that is believed to be involved in an `off-switch' to transition-metal binding. Atomic resolution (<1.1 Å) complexes define the metal-ion site and also reveal the binding of an unusual fructosylated oligosaccharide, which was presumably present as a contaminant in the cellohexaose used for crystallization. Although it has not been possible to detect a biological role for the unusual metal-ion site, this work highlights the need to study some of the many metal-ion sites in carbohydrate-active enzymes that have long been overlooked or previously mis-assigned.
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Affiliation(s)
- Saioa Urresti
- York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, England
| | - Alan Cartmell
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE1 7RU, England
| | - Feng Liu
- Department of Chemistry, University of British Columbia, Vancouver V6T 1Z1, Canada
| | - Paul H. Walton
- Department of Chemistry, University of York, York YO10 5DD, England
| | - Gideon J. Davies
- York Structural Biology Laboratory, Department of Chemistry, University of York, York YO10 5DD, England
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8
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Liu B, Kognole AA, Wu M, Westereng B, Crowley MF, Kim S, Dimarogona M, Payne CM, Sandgren M. Structural and molecular dynamics studies of a C1‐oxidizing lytic polysaccharide monooxygenase from
Heterobasidion irregulare
reveal amino acids important for substrate recognition. FEBS J 2018; 285:2225-2242. [DOI: 10.1111/febs.14472] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 03/28/2018] [Accepted: 04/09/2018] [Indexed: 12/29/2022]
Affiliation(s)
- Bing Liu
- Department of Molecular Sciences Swedish University of Agricultural Sciences Uppsala Sweden
| | - Abhishek A. Kognole
- Department of Chemical and Materials Engineering University of Kentucky Lexington KY USA
| | - Miao Wu
- Department of Molecular Sciences Swedish University of Agricultural Sciences Uppsala Sweden
| | - Bjørge Westereng
- Department of Chemistry, Biotechnology, and Food Science Norwegian University of Life Sciences Ås Norway
| | | | - Seonah Kim
- Biosciences Center National Renewable Energy Laboratory Golden CO USA
| | - Maria Dimarogona
- Department of Molecular Sciences Swedish University of Agricultural Sciences Uppsala Sweden
- Department of Chemical Engineering University of Patras Greece
| | - Christina M. Payne
- Department of Chemical and Materials Engineering University of Kentucky Lexington KY USA
- Directorate of Engineering Division of Chemical, Bioengineering, Environmental, and Transport Systems National Science Foundation Alexandria VA USA
| | - Mats Sandgren
- Department of Molecular Sciences Swedish University of Agricultural Sciences Uppsala Sweden
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9
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Liu B, Olson Å, Wu M, Broberg A, Sandgren M. Biochemical studies of two lytic polysaccharide monooxygenases from the white-rot fungus Heterobasidion irregulare and their roles in lignocellulose degradation. PLoS One 2017; 12:e0189479. [PMID: 29228039 PMCID: PMC5724852 DOI: 10.1371/journal.pone.0189479] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 11/27/2017] [Indexed: 12/05/2022] Open
Abstract
Lytic polysaccharide monooxygenases (LPMO) are important redox enzymes produced by microorganisms for the degradation of recalcitrant natural polysaccharides. Heterobasidion irregulare is a white-rot phytopathogenic fungus that causes wood decay in conifers. The genome of this fungus encodes 10 putative Auxiliary Activity family 9 (AA9) LPMOs. We describe the first biochemical characterization of H. irregulare LPMOs through heterologous expression of two CBM-containing LPMOs from this fungus (HiLPMO9H, HiLPMO9I) in Pichia pastoris. The oxidization preferences and substrate specificities of these two enzymes were determined. The two LPMOs were shown to cleave different carbohydrate components of plant cell walls. HiLPMO9H was active on cellulose and oxidized the substrate at the C1 carbon of the pyranose ring at β-1,4-glycosidic linkages, whereas HiLPMO9I cleaved cellulose with strict oxidization at the C4 carbon of glucose unit at internal bonds, and also showed activity against glucomannan. We propose that the two LPMOs play different roles in the plant-cell-wall degrading system of H. irregulare for degradation of softwood and that the lignocellulose degradation mediated by this white-rot fungus may require collective efforts from multi-types of LPMOs.
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Affiliation(s)
- Bing Liu
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Åke Olson
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Miao Wu
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Anders Broberg
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Mats Sandgren
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
- * E-mail:
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10
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Rodrigues KB, Macêdo JKA, Teixeira T, Barros JS, Araújo ACB, Santos FP, Quirino BF, Brasil BSAF, Salum TFC, Abdelnur PV, Fávaro LCL. Recombinant expression of Thermobifida fusca E7 LPMO in Pichia pastoris and Escherichia coli and their functional characterization. Carbohydr Res 2017; 448:175-181. [PMID: 28411891 DOI: 10.1016/j.carres.2017.04.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 04/07/2017] [Accepted: 04/07/2017] [Indexed: 10/19/2022]
Abstract
The discovery of lytic polysaccharides monooxygenases copper dependent (LPMOs) revolutionized the classical concept that the cleavage of cellulose is a hydrolytic process in recent years. These enzymes carry out oxidative cleavage of cellulose (and other polysaccharides), acting synergistically with cellulases and other hydrolases. In fact, LPMOs have the potential for increasing the efficiency of the lignocellulosic biomass conversion in biofuels and high value chemicals. Among a small number of microbial LPMOs that have been characterized, some LPMOs were expressed and characterized biochemically from the bacteria Thermobifida fusca, using the host Escherichia coli. In this work, the E7 LPMO protein of T. fusca was expressed both in E. coli (native DNA sequence) and Pichia pastoris (codon-optimized DNA sequence), for further analysis of oxidative cleavage, with PASC (phosphoric acid swollen cellulose) and Avicel PH-101 substrates, using mass spectrometry analysis. Mass spectra results of Avicel PH-101 and PASC cleavages by purified E7 LPMO expressed in E. coli and in P. pastoris allowed the visualization of compounds corresponding to oxidized and non-oxidized oligosaccharides. Further optimization of reactions will be performed, since it was found only one degree of polymerization (DP 7). This work demonstrated that it is possible to produce the E7 LPMO from T. fusca in the host P. pastoris, and the recombinant protein was shown to be active on cellulose. The approach used in the present work could be an alternative to produce this bacterial LPMO for cellulose cleavage.
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Affiliation(s)
- Kelly B Rodrigues
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil.
| | - Jéssica K A Macêdo
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil
| | - Tallyta Teixeira
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil; Federal University of Tocantins, Campus Gurupi, 77402-970, Gurupi, TO, Brazil
| | - Jéssica S Barros
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil
| | - Ana C B Araújo
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil
| | - Fernanda P Santos
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil; Federal University of Tocantins, Campus Gurupi, 77402-970, Gurupi, TO, Brazil
| | - Betânia F Quirino
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil
| | - Bruno S A F Brasil
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil
| | - Thaís F C Salum
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil
| | - Patrícia V Abdelnur
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil; Institute of Chemistry, Federal University of Goiás, Campus Samambaia, 74690-900, Goiânia, GO, Brazil
| | - Léia C L Fávaro
- Brazilian Agricultural Research Corporation, Embrapa Agroenergy, W3 Norte, PqEB, 70770-901, Brasília, DF, Brazil.
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11
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Osiro KO, de Camargo BR, Satomi R, Hamann PRV, Silva JP, de Sousa MV, Quirino BF, Aquino EN, Felix CR, Murad AM, Noronha EF. Characterization of Clostridium thermocellum (B8) secretome and purified cellulosomes for lignocellulosic biomass degradation. Enzyme Microb Technol 2017; 97:43-54. [DOI: 10.1016/j.enzmictec.2016.11.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Revised: 11/04/2016] [Accepted: 11/05/2016] [Indexed: 11/16/2022]
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12
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Villares A, Moreau C, Bennati-Granier C, Garajova S, Foucat L, Falourd X, Saake B, Berrin JG, Cathala B. Lytic polysaccharide monooxygenases disrupt the cellulose fibers structure. Sci Rep 2017; 7:40262. [PMID: 28071716 PMCID: PMC5223172 DOI: 10.1038/srep40262] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 12/05/2016] [Indexed: 12/28/2022] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are a class of powerful oxidative enzymes that breakdown recalcitrant polysaccharides such as cellulose. Here we investigate the action of LPMOs on cellulose fibers. After enzymatic treatment and dispersion, LPMO-treated fibers show intense fibrillation. Cellulose structure modifications visualized at different scales indicate that LPMO creates nicking points that trigger the disintegration of the cellulose fibrillar structure with rupture of chains and release of elementary nanofibrils. Investigation of LPMO action using solid-state NMR provides direct evidence of modification of accessible and inaccessible surfaces surrounding the crystalline core of the fibrils. The chains breakage likely induces modifications of the cellulose network and weakens fibers cohesion promoting their disruption. Besides the formation of new initiation sites for conventional cellulases, this work provides the first evidence of the direct oxidative action of LPMOs with the mechanical weakening of the cellulose ultrastructure. LPMOs can be viewed as promising biocatalysts for enzymatic modification or degradation of cellulose fibers.
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Affiliation(s)
| | | | - Chloé Bennati-Granier
- Biodiversité et Biotechnologie Fongiques, INRA, Aix Marseille Univ, UMR1163, 13009, Marseille, France
| | - Sona Garajova
- Biodiversité et Biotechnologie Fongiques, INRA, Aix Marseille Univ, UMR1163, 13009, Marseille, France
| | | | | | - Bodo Saake
- Chemical Wood Technology, University of Hamburg, Leuschnerstraße 91b, 21031 Hamburg, Germany
| | - Jean-Guy Berrin
- Biodiversité et Biotechnologie Fongiques, INRA, Aix Marseille Univ, UMR1163, 13009, Marseille, France
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Frandsen KEH, Poulsen JCN, Tovborg M, Johansen KS, Lo Leggio L. Learning from oligosaccharide soaks of crystals of an AA13 lytic polysaccharide monooxygenase: crystal packing, ligand binding and active-site disorder. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2017; 73:64-76. [PMID: 28045386 DOI: 10.1107/s2059798316019641] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 12/08/2016] [Indexed: 01/09/2023]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are a class of copper-dependent enzymes discovered within the last ten years. They oxidatively cleave polysaccharides (chitin, lignocellulose, hemicellulose and starch-derived), presumably making recalcitrant substrates accessible to glycoside hydrolases. Recently, the first crystal structure of an LPMO-substrate complex was reported, giving insights into the interaction of LPMOs with β-linked substrates (Frandsen et al., 2016). The LPMOs acting on α-linked glycosidic bonds (family AA13) display binding surfaces that are quite different from those of LPMOs that act on β-linked glycosidic bonds (families AA9-AA11), as revealed from the first determined structure (Lo Leggio et al., 2015), and thus presumably the AA13s interact with their substrate in a distinct fashion. Here, several new structures of the same AA13 enzyme, Aspergillus oryzae AA13, are presented. Crystals obtained in the presence of high zinc-ion concentrations were used, as they can be obtained more reproducibly than those used to refine the deposited copper-containing structure. One structure with an ordered zinc-bound active site was solved at 1.65 Å resolution, and three structures from crystals soaked with maltooligosaccharides in solutions devoid of zinc ions were solved at resolutions of up to 1.10 Å. Despite similar unit-cell parameters, small rearrangements in the crystal packing occur when the crystals are depleted of zinc ions, resulting in a more occluded substrate-binding surface. In two of the three structures maltooligosaccharide ligands are bound, but not at the active site. Two of the structures presented show a His-ligand conformation that is incompatible with metal-ion binding. In one of these structures this conformation is the principal one (80% occupancy), giving a rare atomic resolution view of a substantially misfolded enzyme that is presumably rendered inactive.
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Affiliation(s)
- Kristian E H Frandsen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | | | | | - Katja S Johansen
- Department of Geoscience and Natural Resource Management, University of Copenhagen, Rolighedsvej 23, Frederiksberg C, 1958 Copenhagen, Denmark
| | - Leila Lo Leggio
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
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Frandsen KEH, Lo Leggio L. Lytic polysaccharide monooxygenases: a crystallographer's view on a new class of biomass-degrading enzymes. IUCRJ 2016; 3:448-467. [PMID: 27840684 PMCID: PMC5094447 DOI: 10.1107/s2052252516014147] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Accepted: 09/05/2016] [Indexed: 05/05/2023]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are a new class of microbial copper enzymes involved in the degradation of recalcitrant polysaccharides. They have only been discovered and characterized in the last 5-10 years and have stimulated strong interest both in biotechnology and in bioinorganic chemistry. In biotechnology, the hope is that these enzymes will finally help to make enzymatic biomass conversion, especially of lignocellulosic plant waste, economically attractive. Here, the role of LPMOs is likely to be in attacking bonds that are not accessible to other enzymes. LPMOs have attracted enormous interest since their discovery. The emphasis in this review is on the past and present contribution of crystallographic studies as a guide to functional understanding, with a final look towards the future.
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Affiliation(s)
- Kristian E. H. Frandsen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Leila Lo Leggio
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
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15
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Abstract
The recent discovery of copper-dependent lytic polysaccharide mono-oxygenases (LPMOs) has opened up a vast area of research covering several fields of application. The biotech company Novozymes A/S holds patents on the use of these enzymes for the conversion of steam-pre-treated plant residues such as straw to free sugars. These patents predate the correct classification of LPMOs and the striking synergistic effect of fungal LPMOs when combined with canonical cellulases was discovered when fractions of fungal secretomes were evaluated in industrially relevant enzyme performance assays. Today, LPMOs are a central component in the Cellic CTec enzyme products which are used in several large-scale plants for the industrial production of lignocellulosic ethanol. LPMOs are characterized by an N-terminal histidine residue which, together with an internal histidine and a tyrosine residue, co-ordinates a single copper atom in a so-called histidine brace. The mechanism by which oxygen binds to the reduced copper atom has been reported and the general mechanism of copper-oxygen-mediated activation of carbon is being investigated in the light of these discoveries. LPMOs are widespread in both the fungal and the bacterial kingdoms, although the range of action of these enzymes remains to be elucidated. However, based on the high abundance of LPMOs expressed by microbes involved in the decomposition of organic matter, the importance of LPMOs in the natural carbon-cycle is predicted to be significant. In addition, it has been suggested that LPMOs play a role in the pathology of infectious diseases such as cholera and to thus be relevant in the field of medicine.
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Corrêa TLR, dos Santos LV, Pereira GAG. AA9 and AA10: from enigmatic to essential enzymes. Appl Microbiol Biotechnol 2016; 100:9-16. [PMID: 26476647 DOI: 10.1007/s00253-015-7040-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 09/20/2015] [Accepted: 09/24/2015] [Indexed: 12/15/2022]
Abstract
The lignocellulosic biomass, comprised mainly of cellulose, hemicellulose, and lignin, is a strong competitor for petroleum to obtain fuels and other products because of its renewable nature, low cost, and non-competitiveness with food production when obtained from agricultural waste. Due to its recalcitrance, lignocellulosic material requires an arsenal of enzymes for its deconstruction and the consequent release of fermentable sugars. In this context, enzymes currently classified as auxiliary activity 9 (AA9/formerly GH61) and 10 (AA10/formerly CBM 33) or lytic polysaccharide monooxygenases (LPMO) have emerged as cellulase boosting enzymes. AA9 and AA10 are the new paradigm for deconstruction of lignocellulosic biomass by enhancing the activity and decreasing the loading of classical enzymes to the reaction and, consequently, reducing costs of the hydrolysis step in the second-generation ethanol production chain. In view of that disclosed above, the goal of this work is to review experimental data that supports the relevance of AA9 and AA10 for the biomass deconstruction field.
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Moses V, Hatherley R, Tastan Bishop Ö. Bioinformatic characterization of type-specific sequence and structural features in auxiliary activity family 9 proteins. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:239. [PMID: 27833654 PMCID: PMC5101804 DOI: 10.1186/s13068-016-0655-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 10/25/2016] [Indexed: 05/22/2023]
Abstract
BACKGROUND Due to the impending depletion of fossil fuels, it has become important to identify alternative energy sources. The biofuel industry has proven to be a promising alternative. However, owing to the complex nature of plant biomass, hence the degradation, biofuel production remains a challenge. The copper-dependent Auxiliary Activity family 9 (AA9) proteins have been found to act synergistically with other cellulose-degrading enzymes resulting in an increased rate of cellulose breakdown. AA9 proteins are lytic polysaccharide monooxygenase (LPMO) enzymes, otherwise known as polysaccharide monooxygenases (PMOs). They are further classified as Type 1, 2 or 3 PMOs, depending on the different cleavage products formed. As AA9 proteins are known to exhibit low sequence conservation, the analysis of unique features of AA9 domains of these enzymes should provide insights for the better understanding of how different AA9 PMO types function. RESULTS Bioinformatics approaches were used to identify features specific to the catalytic AA9 domains of each type of AA9 PMO. Sequence analysis showed the N terminus to be highly variable with type-specific inserts evident in this region. Phylogenetic analysis was performed to cluster AA9 domains based on their types. Motif analysis enabled the identification of sub-groups within each AA9 PMO type with the majority of these motifs occurring within the highly variable N terminus of AA9 domains. AA9 domain structures were manually docked to crystalline cellulose and used to analyze both the type-specific inserts and motifs at a structural level. The results indicated that these regions influence the AA9 domain active site topology and may contribute to the regioselectivity displayed by different AA9 PMO types. Physicochemical property analysis was performed and detected significant differences in aromaticity, isoelectric point and instability index between certain AA9 PMO types. CONCLUSIONS In this study, a type-specific characterisation of AA9 domains was performed using various bioinformatics approaches. These highly variable proteins were found to have a greater degree of conservation within their respective types. Type-specific features were identified for AA9 domains, which could be observed at a sequence, structural and physicochemical level. This provides a basis under which to identify and group new AA9 LPMOs in future.
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Affiliation(s)
- Vuyani Moses
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, 6140 South Africa
| | - Rowan Hatherley
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, 6140 South Africa
| | - Özlem Tastan Bishop
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, 6140 South Africa
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Jung S, Song Y, Kim HM, Bae HJ. Enhanced lignocellulosic biomass hydrolysis by oxidative lytic polysaccharide monooxygenases (LPMOs) GH61 from Gloeophyllum trabeum. Enzyme Microb Technol 2015; 77:38-45. [DOI: 10.1016/j.enzmictec.2015.05.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 05/20/2015] [Accepted: 05/21/2015] [Indexed: 01/13/2023]
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19
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Nam YW, Nihira T, Arakawa T, Saito Y, Kitaoka M, Nakai H, Fushinobu S. Crystal Structure and Substrate Recognition of Cellobionic Acid Phosphorylase, Which Plays a Key Role in Oxidative Cellulose Degradation by Microbes. J Biol Chem 2015; 290:18281-92. [PMID: 26041776 DOI: 10.1074/jbc.m115.664664] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Indexed: 01/02/2023] Open
Abstract
The microbial oxidative cellulose degradation system is attracting significant research attention after the recent discovery of lytic polysaccharide mono-oxygenases. A primary product of the oxidative and hydrolytic cellulose degradation system is cellobionic acid (CbA), the aldonic acid form of cellobiose. We previously demonstrated that the intracellular enzyme belonging to glycoside hydrolase family 94 from cellulolytic fungus and bacterium is cellobionic acid phosphorylase (CBAP), which catalyzes reversible phosphorolysis of CbA into glucose 1-phosphate and gluconic acid (GlcA). In this report, we describe the biochemical characterization and the three-dimensional structure of CBAP from the marine cellulolytic bacterium Saccharophagus degradans. Structures of ligand-free and complex forms with CbA, GlcA, and a synthetic disaccharide product from glucuronic acid were determined at resolutions of up to 1.6 Å. The active site is located near the dimer interface. At subsite +1, the carboxylate group of GlcA and CbA is recognized by Arg-609 and Lys-613. Additionally, one residue from the neighboring protomer (Gln-190) is involved in the carboxylate recognition of GlcA. A mutational analysis indicated that these residues are critical for the binding and catalysis of the aldonic and uronic acid acceptors GlcA and glucuronic acid. Structural and sequence comparisons with other glycoside hydrolase family 94 phosphorylases revealed that CBAPs have a unique subsite +1 with a distinct amino acid residue conservation pattern at this site. This study provides molecular insight into the energetically efficient metabolic pathway of oxidized sugars that links the oxidative cellulolytic pathway to the glycolytic and pentose phosphate pathways in cellulolytic microbes.
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Affiliation(s)
- Young-Woo Nam
- From the Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Takanori Nihira
- Faculty of Agriculture, Niigata University, Niigata 950-2181, Japan, and
| | - Takatoshi Arakawa
- From the Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Yuka Saito
- Faculty of Agriculture, Niigata University, Niigata 950-2181, Japan, and
| | - Motomitsu Kitaoka
- National Food Research Institute, National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-8642, Japan
| | - Hiroyuki Nakai
- Faculty of Agriculture, Niigata University, Niigata 950-2181, Japan, and
| | - Shinya Fushinobu
- From the Department of Biotechnology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan,
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20
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Classification of fungal and bacterial lytic polysaccharide monooxygenases. BMC Genomics 2015; 16:368. [PMID: 25956378 PMCID: PMC4424831 DOI: 10.1186/s12864-015-1601-6] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 04/29/2015] [Indexed: 11/21/2022] Open
Abstract
Background Lytic polysaccharide monooxygenases are important enzymes for the decomposition of recalcitrant biological macromolecules such as plant cell wall and chitin polymers. These enzymes were originally designated glycoside hydrolase family 61 and carbohydrate-binding module family 33 but are now classified as auxiliary activities 9, 10 and 11 in the CAZy database. To obtain a systematic analysis of the divergent families of lytic polysaccharide monooxygenases we used Peptide Pattern Recognition to divide 5396 protein sequences resembling enzymes from families AA9 (1828 proteins), AA10 (2799 proteins) and AA11 (769 proteins) into subfamilies. Results The results showed that the lytic polysaccharide monooxygenases have two conserved regions identified by conserved peptides specific for each AA family. The peptides were used for in silico PCR discovery of the lytic polysaccharide monooxygenases in 79 fungal and 95 bacterial genomes. The bacterial genomes encoded 0 – 7 AA10s (average 0.6). No AA9 or AA11 were found in the bacteria. The fungal genomes encoded 0 – 40 AA9s (average 7) and 0 – 15 AA11s (average 2) and two of the fungi possessed a gene encoding a putative AA10. The AA9s were mainly found in plant cell wall-degrading asco- and basidiomycetes in agreement with the described role of AA9 enzymes. In contrast, the AA11 proteins were found in 36 of the 39 ascomycetes and in only two of the 32 basidiomycetes and their abundance did not correlate to the degradation of cellulose and hemicellulose. Conclusions These results provides an overview of the sequence characteristics and occurrence of the divergent AA9, AA10 and AA11 families and pave the way for systematic investigations of the of lytic polysaccharide monooxygenases and for structure-function studies of these enzymes. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1601-6) contains supplementary material, which is available to authorized users.
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Morgenstern I, Powlowski J, Tsang A. Fungal cellulose degradation by oxidative enzymes: from dysfunctional GH61 family to powerful lytic polysaccharide monooxygenase family. Brief Funct Genomics 2014; 13:471-81. [PMID: 25217478 PMCID: PMC4239789 DOI: 10.1093/bfgp/elu032] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Our understanding of fungal cellulose degradation has shifted dramatically in the past few years with the characterization of a new class of secreted enzymes, the lytic polysaccharide monooxygenases (LPMO). After a period of intense research covering structural, biochemical, theoretical and evolutionary aspects, we have a picture of them as wedge-like copper-dependent metalloenzymes that on reduction generate a radical copper-oxyl species, which cleaves mainly crystalline cellulose. The main biological function lies in the synergism of fungal LPMOs with canonical hydrolytic cellulases in achieving efficient cellulose degradation. Their important role in cellulose degradation is highlighted by the wide distribution and often numerous occurrences in the genomes of almost all plant cell-wall degrading fungi. In this review, we provide an overview of the latest achievements in LPMO research and consider the open questions and challenges that undoubtedly will continue to stimulate interest in this new and exciting group of enzymes.
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Kricka W, Fitzpatrick J, Bond U. Metabolic engineering of yeasts by heterologous enzyme production for degradation of cellulose and hemicellulose from biomass: a perspective. Front Microbiol 2014; 5:174. [PMID: 24795706 PMCID: PMC4001029 DOI: 10.3389/fmicb.2014.00174] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 03/31/2014] [Indexed: 11/13/2022] Open
Abstract
This review focuses on current approaches to metabolic engineering of ethanologenic yeast species for the production of bioethanol from complex lignocellulose biomass sources. The experimental strategies for the degradation of the cellulose and xylose-components of lignocellulose are reviewed. Limitations to the current approaches are discussed and novel solutions proposed.
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Affiliation(s)
- William Kricka
- School of Genetics and Microbiology, Department of Microbiology, Trinity College Dublin Dublin, Ireland
| | - James Fitzpatrick
- School of Genetics and Microbiology, Department of Microbiology, Trinity College Dublin Dublin, Ireland
| | - Ursula Bond
- School of Genetics and Microbiology, Department of Microbiology, Trinity College Dublin Dublin, Ireland
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Harris PV, Xu F, Kreel NE, Kang C, Fukuyama S. New enzyme insights drive advances in commercial ethanol production. Curr Opin Chem Biol 2014; 19:162-70. [DOI: 10.1016/j.cbpa.2014.02.015] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 02/08/2014] [Accepted: 02/12/2014] [Indexed: 01/19/2023]
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Fitzpatrick J, Kricka W, James TC, Bond U. Expression of three Trichoderma reesei cellulase genes in Saccharomyces pastorianus for the development of a two-step process of hydrolysis and fermentation of cellulose. J Appl Microbiol 2014; 117:96-108. [PMID: 24666670 DOI: 10.1111/jam.12494] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 02/26/2014] [Accepted: 03/04/2014] [Indexed: 11/26/2022]
Abstract
AIMS To compare the production of recombinant cellulase enzymes in two Saccharomyces species so as to ascertain the most suitable heterologous host for the degradation of cellulose-based biomass and its conversion into bioethanol. METHOD AND RESULTS cDNA copies of genes representing the three major classes of cellulases (Endoglucanases, Cellobiohydrolases and β-glucosidases) from Trichoderma reesei were expressed in Saccharomyces pastorianus and Saccharomyces cerevisiae. The recombinant enzymes were secreted by the yeast hosts into the medium and were shown to act in synergy to hydrolyse cellulose. The conditions required to achieve maximum release of glucose from cellulose by the recombinant enzymes were defined and the activity of the recombinant enzymes was compared to a commercial cocktail of T. reesei cellulases. CONCLUSIONS We demonstrate that significantly higher levels of cellulase activity were achieved by expression of the genes in S. pastorianus compared to S. cerevisiae. Hydrolysis of cellulose by the combined activity of the recombinant enzymes was significantly better at 50°C than at 30°C, the temperature used for mesophilic yeast fermentations, reflecting the known temperature profiles of the native enzymes. SIGNIFICANCE AND IMPACT OF THE STUDY The results demonstrate that host choice is important for the heterologous production of cellulases. On the basis of the low activity of the T. reesei recombinant enzymes at fermentation temperatures, we propose a two-step process for the hydrolysis of cellulose and its fermentation into alcohol using cellulases produced in situ.
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Affiliation(s)
- J Fitzpatrick
- School of Genetics and Microbiology, Moyne Institute, Trinity College Dublin, College Green, Dublin 2, Ireland
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25
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Cannella D, Jørgensen H. Do new cellulolytic enzyme preparations affect the industrial strategies for high solids lignocellulosic ethanol production? Biotechnol Bioeng 2013; 111:59-68. [DOI: 10.1002/bit.25098] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Revised: 06/21/2013] [Accepted: 08/12/2013] [Indexed: 11/11/2022]
Affiliation(s)
- David Cannella
- Faculty of Science; University of Copenhagen; Rolighedsvej 23 Frederiksberg Denmark
| | - Henning Jørgensen
- Faculty of Science; University of Copenhagen; Rolighedsvej 23 Frederiksberg Denmark
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Hemsworth GR, Davies GJ, Walton PH. Recent insights into copper-containing lytic polysaccharide mono-oxygenases. Curr Opin Struct Biol 2013; 23:660-8. [PMID: 23769965 DOI: 10.1016/j.sbi.2013.05.006] [Citation(s) in RCA: 146] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 05/15/2013] [Accepted: 05/16/2013] [Indexed: 12/18/2022]
Abstract
Recently the role of oxidative enzymes in the degradation of polysaccharides by saprophytic bacteria and fungi was uncovered, challenging the classical model of polysaccharide degradation of being solely via a hydrolytic pathway. 3D structural analyses of lytic polysaccharide mono-oxygenases of both bacterial AA10 (formerly CBM33) and fungal AA9 (formerly GH61) enzymes revealed structures with β-sandwich folds containing an active site with a metal coordinated by an N-terminal histidine. Following some initial confusion about the identity of the metal ion it has now been shown that these enzymes are copper-dependent oxygenases. Here we assess recent developments in the academic literature, focussing on the structures of the copper active sites. We provide critical comparisons with known small-molecules studies of copper-oxygen complexes and with copper methane monoxygenase, another of nature's powerful copper oxygenases.
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Affiliation(s)
- Glyn R Hemsworth
- Department of Chemistry, University of York, Heslington, York YO10 5DD, UK
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Ekwe E, Morgenstern I, Tsang A, Storms R, Powlowski J. Non-Hydrolytic Cellulose Active Proteins: Research Progress and Potential Application in Biorefineries. Ind Biotechnol (New Rochelle N Y) 2013. [DOI: 10.1089/ind.2013.0010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Enongene Ekwe
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Quebec, Canada
- Department of Chemistry and Biochemistry, Concordia University, Montreal, Quebec, Canada
| | - Ingo Morgenstern
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Quebec, Canada
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Adrian Tsang
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Quebec, Canada
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Reginald Storms
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Quebec, Canada
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Justin Powlowski
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Quebec, Canada
- Department of Chemistry and Biochemistry, Concordia University, Montreal, Quebec, Canada
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