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Kao CT, Yang FW, Wu MC, Hung TH, Hu CW, Chen CH, Liou PC, Mai TL, Chang CC, Lin TY, Chen YL, Lin YCJ, Su JC. Systematic synthesis and identification of monolignol pathway metabolites. THE NEW PHYTOLOGIST 2024. [PMID: 39267260 DOI: 10.1111/nph.20101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2024] [Accepted: 08/15/2024] [Indexed: 09/17/2024]
Abstract
Monolignol serves as the building blocks to constitute lignin, the second abundant polymer on Earth. Despite two decades of diligent efforts, complete identification of all metabolites in the currently proposed monolignol biosynthesis pathway has proven elusive. This limitation also hampers their potential application. One of the primary obstacles is the challenge of assembling a collection of all molecules, because many are commercially unavailable or prohibitively costly. In this study, we established systematic pipelines to synthesize all 24 molecules through the conversions between functional groups on a core structure followed by the application to other core structures. We successfully identified all of them in Populus trichocarpa and Eucalyptus grandis, two representative species respectively from malpighiales and myrtales in angiosperms. Knowledge about monolignol metabolite chemosynthesis and identification will form the foundation for future studies.
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Affiliation(s)
- Chung-Ting Kao
- Institute of Plant Biology, College of Life Science, National Taiwan University, Taipei, 106319, Taiwan
| | - Fan-Wei Yang
- College of Pharmaceutical Sciences, Department of Pharmacy, National Yang Ming Chiao Tung University, Taipei, 112304, Taiwan
| | - Meng-Chen Wu
- College of Pharmaceutical Sciences, Department of Pharmacy, National Yang Ming Chiao Tung University, Taipei, 112304, Taiwan
- Department of Life Science, College of Life Science, National Taiwan University, Taipei, 106319, Taiwan
| | - Tzu-Huan Hung
- Crop Genetic Resources and Biotechnology Division, Taiwan Agricultural Research Institute, Taichung, 41362, Taiwan
| | - Chen-Wei Hu
- Department of Life Science, College of Life Science, National Taiwan University, Taipei, 106319, Taiwan
| | - Chiu-Hua Chen
- Crop Genetic Resources and Biotechnology Division, Taiwan Agricultural Research Institute, Taichung, 41362, Taiwan
| | - Pin-Chien Liou
- Institute of Plant Biology, College of Life Science, National Taiwan University, Taipei, 106319, Taiwan
| | - Te-Lun Mai
- Department of Life Science, College of Life Science, National Taiwan University, Taipei, 106319, Taiwan
| | - Chia-Chih Chang
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, Hsinchu, 300093, Taiwan
| | - Tung-Yi Lin
- Institute of Traditional Medicine, National Yang Ming Chiao Tung University, Taipei, 112304, Taiwan
- Program in Molecular Medicine, National Yang Ming Chiao Tung University, Taipei, 112304, Taiwan
- School of Chinese Medicine, National Yang Ming Chiao Tung University, Taipei, 112304, Taiwan
| | - Ying-Lan Chen
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, 701401, Taiwan
- University Center of Bioscience and Biotechnology, National Cheng Kung University, Tainan, 701401, Taiwan
| | - Ying-Chung Jimmy Lin
- Institute of Plant Biology, College of Life Science, National Taiwan University, Taipei, 106319, Taiwan
- Department of Life Science, College of Life Science, National Taiwan University, Taipei, 106319, Taiwan
- Genome and Systems Biology Degree Program, National Taiwan University and Academia Sinica, Taipei, 106319, Taiwan
| | - Jung-Chen Su
- College of Pharmaceutical Sciences, Department of Pharmacy, National Yang Ming Chiao Tung University, Taipei, 112304, Taiwan
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Yang HD, Tang ZS, Xue TT, Zhu YY, Su ZH, Xu HB. Acyl-quinic acids from the root bark of Acanthopanax gracilistylus and their inhibitory effects on neutrophil elastase and cyclooxygenase-2 in vitro. Bioorg Chem 2023; 140:106798. [PMID: 37634270 DOI: 10.1016/j.bioorg.2023.106798] [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: 06/19/2023] [Revised: 08/09/2023] [Accepted: 08/19/2023] [Indexed: 08/29/2023]
Abstract
Eleven new acyl-quinic acids (AQAs) 1a-9, and 18 known AQAs 10-27 were isolated from the root bark of Acanthopanax gracilistylus W. W. Smith (Acanthopanacis Cortex). The planar structures of 1a-9 were determined based on their HR-ESIMS, IR, and NMR data. The absolute configurations of 1a-6 were identified by comparing the experimental and the calculated electronic circular dichroism (ECD) spectra. This is the first report of the isolation of AQAs from Acanthopanacis Cortex. Notably, 1a-6 were determined as unusual oxyneolignan-(-)-quinic acids heterodimers, representing a new class of natural products. The inhibitory activities of 1a-27 on neutrophil elastase (NE) and cyclooxygenase-2 (COX-2) were studied in vitro, and the results indicated they possessed significant inhibitory activities on COX-2. Among them, the IC50 values of 1a-9 were 0.63±0.014, 0.75±0.028, 0.15±0.023, 0.63±0.016, 0.30±0.013, 35.63±4.600, 8.70±1.241, 16.51±0.480, 0.69±0.049, 0.39±0.017, and 0.26±0.080 μM, respectively. This study represents the inaugural disclosure of the anti-COX-2 constituents found in Acanthopanacis Cortex, thereby furnishing valuable insights into the exploration of novel COX-2 inhibitors derived from natural reservoirs.
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Affiliation(s)
- Hao-Dong Yang
- Co-construction Collaborative Innovation Center for Chinese Medicine Resources Industrialization by Shaanxi & Education Ministry, State Key Laboratory of Research & Development of Characteristic Qin Medicine Resources (Cultivation), Shaanxi University of Chinese Medicine, Xianyang 712083, PR China
| | - Zhi-Shu Tang
- Co-construction Collaborative Innovation Center for Chinese Medicine Resources Industrialization by Shaanxi & Education Ministry, State Key Laboratory of Research & Development of Characteristic Qin Medicine Resources (Cultivation), Shaanxi University of Chinese Medicine, Xianyang 712083, PR China; China Academy of Chinese Medical Sciences, Beijing 100700, PR China
| | - Tao-Tao Xue
- Co-construction Collaborative Innovation Center for Chinese Medicine Resources Industrialization by Shaanxi & Education Ministry, State Key Laboratory of Research & Development of Characteristic Qin Medicine Resources (Cultivation), Shaanxi University of Chinese Medicine, Xianyang 712083, PR China
| | - Ya-Ya Zhu
- Co-construction Collaborative Innovation Center for Chinese Medicine Resources Industrialization by Shaanxi & Education Ministry, State Key Laboratory of Research & Development of Characteristic Qin Medicine Resources (Cultivation), Shaanxi University of Chinese Medicine, Xianyang 712083, PR China
| | - Zeng-Hu Su
- Co-construction Collaborative Innovation Center for Chinese Medicine Resources Industrialization by Shaanxi & Education Ministry, State Key Laboratory of Research & Development of Characteristic Qin Medicine Resources (Cultivation), Shaanxi University of Chinese Medicine, Xianyang 712083, PR China
| | - Hong-Bo Xu
- Co-construction Collaborative Innovation Center for Chinese Medicine Resources Industrialization by Shaanxi & Education Ministry, State Key Laboratory of Research & Development of Characteristic Qin Medicine Resources (Cultivation), Shaanxi University of Chinese Medicine, Xianyang 712083, PR China.
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Martin AF, Tobimatsu Y, Lam PY, Matsumoto N, Tanaka T, Suzuki S, Kusumi R, Miyamoto T, Takeda-Kimura Y, Yamamura M, Koshiba T, Osakabe K, Osakabe Y, Sakamoto M, Umezawa T. Lignocellulose molecular assembly and deconstruction properties of lignin-altered rice mutants. PLANT PHYSIOLOGY 2023; 191:70-86. [PMID: 36124989 PMCID: PMC9806629 DOI: 10.1093/plphys/kiac432] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
Bioengineering approaches to modify lignin content and structure in plant cell walls have shown promise for facilitating biochemical conversions of lignocellulosic biomass into valuable chemicals. Despite numerous research efforts, however, the effect of altered lignin chemistry on the supramolecular assembly of lignocellulose and consequently its deconstruction in lignin-modified transgenic and mutant plants is not fully understood. In this study, we aimed to close this gap by analyzing lignin-modified rice (Oryza sativa L.) mutants deficient in 5-HYDROXYCONIFERALDEHYDE O-METHYLTRANSFERASE (CAldOMT) and CINNAMYL ALCOHOL DEHYDROGENASE (CAD). A set of rice mutants harboring knockout mutations in either or both OsCAldOMT1 and OsCAD2 was generated in part by genome editing and subjected to comparative cell wall chemical and supramolecular structure analyses. In line with the proposed functions of CAldOMT and CAD in grass lignin biosynthesis, OsCAldOMT1-deficient mutant lines produced altered lignins depleted of syringyl and tricin units and incorporating noncanonical 5-hydroxyguaiacyl units, whereas OsCAD2-deficient mutant lines produced lignins incorporating noncanonical hydroxycinnamaldehyde-derived units. All tested OsCAldOMT1- and OsCAD2-deficient mutants, especially OsCAldOMT1-deficient lines, displayed enhanced cell wall saccharification efficiency. Solid-state nuclear magnetic resonance (NMR) and X-ray diffraction analyses of rice cell walls revealed that both OsCAldOMT1- and OsCAD2 deficiencies contributed to the disruptions of the cellulose crystalline network. Further, OsCAldOMT1 deficiency contributed to the increase of the cellulose molecular mobility more prominently than OsCAD2 deficiency, resulting in apparently more loosened lignocellulose molecular assembly. Such alterations in cell wall chemical and supramolecular structures may in part account for the variations of saccharification performance of the OsCAldOMT1- and OsCAD2-deficient rice mutants.
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Affiliation(s)
- Andri Fadillah Martin
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Research Center for Genetic Engineering, National Research and Innovation Agency (BRIN), Bogor, 16911, Indonesia
| | - Yuki Tobimatsu
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Pui Ying Lam
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Center for Crossover Education, Graduate School of Engineering Science, Akita University, Akita, 010-8502, Japan
| | - Naoyuki Matsumoto
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Takuto Tanaka
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Shiro Suzuki
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Faculty of Applied Biological Sciences, Gifu University, Gifu, 501-1193, Japan
| | - Ryosuke Kusumi
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Takuji Miyamoto
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Sakeology Center, Niigata University, Niigata, 950-2181, Japan
| | - Yuri Takeda-Kimura
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Department of Botany, University of Wisconsin-Madison, Madison, Wisconsin, 53706, USA
| | - Masaomi Yamamura
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, 770-8503, Japan
| | - Taichi Koshiba
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- National Agriculture and Food Research Organization, Tsukuba, 305-8517, Japan
| | - Keishi Osakabe
- Faculty of Bioscience and Bioindustry, Tokushima University, Tokushima, 770-8503, Japan
| | - Yuriko Osakabe
- School of Life Science and Technology, Tokyo Institute of Technology, Tokyo, 152-8550, Japan
| | - Masahiro Sakamoto
- Graduate School of Agriculture, Kyoto University, Kyoto, 606-8502, Japan
| | - Toshiaki Umezawa
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji 611-0011, Japan
- Research Unit for Realization of Sustainable Society (RURSS), Kyoto University, Uji, 611-0011, Japan
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Yang X, Li Z, Li L, Li N, Jing F, Hu L, Shang Q, Zhang X, Zhou Y, Pan X. Depolymerization and Demethylation of Kraft Lignin in Molten Salt Hydrate and Applications as an Antioxidant and Metal Ion Scavenger. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:13568-13577. [PMID: 34730357 DOI: 10.1021/acs.jafc.1c05759] [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] [Indexed: 06/13/2023]
Abstract
To improve the reactivity and enrich the functionality of lignin for valorization, kraft lignin was depolymerized and demethylated via cleaving aryl and alkyl ether bonds in acidic lithium bromide trihydrate (∼60% LiBr aqueous solution). It was found that the cleavage of the ether bonds followed the order of β-O-4 ether > aryl alkyl ether in phenylcoumaran > dialkyl ether in resinol > methoxyl (MeO). The depolymerization via β-O-4 cleavage occurred under mild conditions (e.g., <0.5 M HCl at 110 °C), while sufficient demethylation of the lignin needed harsher conditions (>1.5 M HCl). Both depolymerization and demethylation generated new aromatic hydroxyl (ArOH). With 2.4 M HCl, MeO content dropped from 4.85 to 0.95 mmol/g lignin, and ArOH content increased from 2.78 to 5.09 mmol/g lignin. The depolymerized and demethylated kraft lignin showed excellent antioxidant activity and Cr(VI)-scavenging capacity, compared with original kraft lignin and tannins.
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Affiliation(s)
- Xiaohui Yang
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, Wisconsin 53706, United States
- Research Institute of Forestry New Technology, Chinese Academy of Forestry, Dongxiaofu-1 Xiangshan Road, Beijing 100091, China
| | - Zheng Li
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, Wisconsin 53706, United States
| | - Long Li
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
| | - Ning Li
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, Wisconsin 53706, United States
| | - Fei Jing
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
| | - Lihong Hu
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
- Research Institute of Forestry New Technology, Chinese Academy of Forestry, Dongxiaofu-1 Xiangshan Road, Beijing 100091, China
| | - Qianqian Shang
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
| | - Xiao Zhang
- Center for Bioproducts and Bioenergy, Washington State University, 2710 University Drive, Richland, Washington 99354, United States
| | - Yonghong Zhou
- Jiangsu Province Key Laboratory of Biomass Energy and Material; Jiangsu Province Co-Innovation Center of Efficient Processing and Utilization of Forest Resources; Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration; National Engineering Lab. for Biomass Chemical Utilization, Institute of Chemical Industry of Forestry Products, Chinese Academy of Forestry, Nanjing 210042, China
| | - Xuejun Pan
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, Wisconsin 53706, United States
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de Vries L, Guevara-Rozo S, Cho M, Liu LY, Renneckar S, Mansfield SD. Tailoring renewable materials via plant biotechnology. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:167. [PMID: 34353358 PMCID: PMC8344217 DOI: 10.1186/s13068-021-02010-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 07/06/2021] [Indexed: 05/03/2023]
Abstract
Plants inherently display a rich diversity in cell wall chemistry, as they synthesize an array of polysaccharides along with lignin, a polyphenolic that can vary dramatically in subunit composition and interunit linkage complexity. These same cell wall chemical constituents play essential roles in our society, having been isolated by a variety of evolving industrial processes and employed in the production of an array of commodity products to which humans are reliant. However, these polymers are inherently synthesized and intricately packaged into complex structures that facilitate plant survival and adaptation to local biogeoclimatic regions and stresses, not for ease of deconstruction and commercial product development. Herein, we describe evolving techniques and strategies for altering the metabolic pathways related to plant cell wall biosynthesis, and highlight the resulting impact on chemistry, architecture, and polymer interactions. Furthermore, this review illustrates how these unique targeted cell wall modifications could significantly extend the number, diversity, and value of products generated in existing and emerging biorefineries. These modifications can further target the ability for processing of engineered wood into advanced high performance materials. In doing so, we attempt to illuminate the complex connection on how polymer chemistry and structure can be tailored to advance renewable material applications, using all the chemical constituents of plant-derived biopolymers, including pectins, hemicelluloses, cellulose, and lignins.
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Affiliation(s)
- Lisanne de Vries
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
- US Department of Energy (DOE) Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin - Madison, Madison, WI , 53726, USA
| | - Sydne Guevara-Rozo
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - MiJung Cho
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Li-Yang Liu
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Scott Renneckar
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Shawn D Mansfield
- Department of Wood Science, Faculty of Forestry, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
- US Department of Energy (DOE) Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin - Madison, Madison, WI , 53726, USA.
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Miyagawa Y, Tobimatsu Y, Lam PY, Mizukami T, Sakurai S, Kamitakahara H, Takano T. Possible mechanisms for the generation of phenyl glycoside-type lignin-carbohydrate linkages in lignification with monolignol glucosides. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 104:156-170. [PMID: 32623768 DOI: 10.1111/tpj.14913] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 06/17/2020] [Accepted: 06/24/2020] [Indexed: 06/11/2023]
Abstract
The existence and formation of covalent lignin-carbohydrate (LC) linkages in plant cell walls has long been a matter of debate in terms of their roles in cell wall development and biomass use. Of the various putative LC linkages proposed to date, evidence of the native existence and formation mechanism of phenyl glycoside (PG)-type LC linkages in planta is particularly scarce. The present study aimed to explore previously overlooked mechanisms for the formation of PG-type LC linkages through the incorporation of monolignol glucosides, which are possible lignin precursors, into lignin polymers during lignification. Peroxidase-catalyzed lignin polymerization of coniferyl alcohol in the presence of coniferin and syringin in vitro resulted in the generation of PG-type LC linkages in synthetic lignin polymers, possibly via nucleophilic addition onto quinone methide (QM) intermediates formed during polymerization. Biomimetic lignin polymerization of coniferin via the β-glucosidase/peroxidase system also resulted in the generation of PG-type as well as alkyl glycoside-type LC linkages. This occurred via non-enzymatic QM-involving reactions and also via enzymatic transglycosylations involving β-glucosidase, which was demonstrated by in-depth structural analysis of the synthetic lignins by two-dimensional NMR. We collected heteronuclear single-quantum coherence (HSQC) NMR for native cell wall fractions prepared from pine (Pinus taeda), eucalyptus (Eucalyptus camaldulensis), acacia (Acacia mangium), poplar (Populus × eurarnericana) and bamboo (Phyllostachys edulis) wood samples, which exhibited correlations, albeit at low levels, that were well matched with those of the PG-type LC linkages in synthetic lignins incorporating monolignol glucosides. Overall, our results provide a molecular basis for feasible mechanisms for the generation of PG-type LC linkages from monolignol glucosides and further substantiates their existence in planta.
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Affiliation(s)
- Yasuyuki Miyagawa
- Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Kyoto, 606-8502, Japan
| | - Yuki Tobimatsu
- Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Kyoto, 606-8502, Japan
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Pui Ying Lam
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Takahito Mizukami
- Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Kyoto, 606-8502, Japan
| | - Sayaka Sakurai
- Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Kyoto, 606-8502, Japan
| | - Hiroshi Kamitakahara
- Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Kyoto, 606-8502, Japan
| | - Toshiyuki Takano
- Graduate School of Agriculture, Kyoto University, Kitashirakawa-oiwakecho, Kyoto, 606-8502, Japan
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Mnich E, Bjarnholt N, Eudes A, Harholt J, Holland C, Jørgensen B, Larsen FH, Liu M, Manat R, Meyer AS, Mikkelsen JD, Motawia MS, Muschiol J, Møller BL, Møller SR, Perzon A, Petersen BL, Ravn JL, Ulvskov P. Phenolic cross-links: building and de-constructing the plant cell wall. Nat Prod Rep 2020; 37:919-961. [PMID: 31971193 DOI: 10.1039/c9np00028c] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Covering: Up to 2019Phenolic cross-links and phenolic inter-unit linkages result from the oxidative coupling of two hydroxycinnamates or two molecules of tyrosine. Free dimers of hydroxycinnamates, lignans, play important roles in plant defence. Cross-linking of bound phenolics in the plant cell wall affects cell expansion, wall strength, digestibility, degradability, and pathogen resistance. Cross-links mediated by phenolic substituents are particularly important as they confer strength to the wall via the formation of new covalent bonds, and by excluding water from it. Four biopolymer classes are known to be involved in the formation of phenolic cross-links: lignins, extensins, glucuronoarabinoxylans, and side-chains of rhamnogalacturonan-I. Lignins and extensins are ubiquitous in streptophytes whereas aromatic substituents on xylan and pectic side-chains are commonly assumed to be particular features of Poales sensu lato and core Caryophyllales, respectively. Cross-linking of phenolic moieties proceeds via radical formation, is catalyzed by peroxidases and laccases, and involves monolignols, tyrosine in extensins, and ferulate esters on xylan and pectin. Ferulate substituents, on xylan in particular, are thought to be nucleation points for lignin polymerization and are, therefore, of paramount importance to wall architecture in grasses and for the development of technology for wall disassembly, e.g. for the use of grass biomass for production of 2nd generation biofuels. This review summarizes current knowledge on the intra- and extracellular acylation of polysaccharides, and inter- and intra-molecular cross-linking of different constituents. Enzyme mediated lignan in vitro synthesis for pharmaceutical uses are covered as are industrial exploitation of mutant and transgenic approaches to control cell wall cross-linking.
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Affiliation(s)
- Ewelina Mnich
- Department of Plant and Environmental Sciences, University of Copenhagen, Denmark.
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Grabber JH, Davidson C, Tobimatsu Y, Kim H, Lu F, Zhu Y, Opietnik M, Santoro N, Foster CE, Yue F, Ress D, Pan X, Ralph J. Structural features of alternative lignin monomers associated with improved digestibility of artificially lignified maize cell walls. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 287:110070. [PMID: 31481197 DOI: 10.1016/j.plantsci.2019.02.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 02/01/2019] [Accepted: 02/04/2019] [Indexed: 05/19/2023]
Abstract
Plant biologists are seeking new approaches for modifying lignin to improve the digestion and utilization of structural polysaccharides in crop cultivars for the production of biofuels, biochemicals, and livestock. To identify promising targets for lignin bioengineering, we artificially lignified maize (Zea mays L.) cell walls with normal monolignols plus 21 structurally diverse alternative monomers to assess their suitability for lignification and for improving fiber digestibility. Lignin formation and structure were assessed by mass balance, Klason lignin, acetyl bromide lignin, gel-state 2D-NMR and thioacidolysis procedures, and digestibility was evaluated with rumen microflora and from glucose production by fungal enzymes following mild acid or base pretreatments. Highly acidic or hydrophilic monomers proved unsuitable for lignin modification because they severely depressed cell wall lignification. By contrast, monomers designed to moderately alter hydrophobicity or introduce cleavable acetal, amide, or ester functionalities into the polymer often readily formed lignin, but most failed to improve digestibility, even after chemical pretreatment. Fortunately, several types of phenylpropanoid derivatives containing multiple ester-linked catechol or pyrogallol units were identified as desirable genetic engineering targets because they readily formed wall-bound polymers and improved digestibility, presumably by blocking cross-linking of lignin to structural polysaccharides and promoting lignin fragmentation during mild acidic and especially alkaline pretreatment.
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Affiliation(s)
| | - Christy Davidson
- Department of Biochemistry, and D.O.E. Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Yuki Tobimatsu
- Department of Biochemistry, and D.O.E. Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Hoon Kim
- Department of Biochemistry, and D.O.E. Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Fachuang Lu
- Department of Biochemistry, and D.O.E. Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Yimin Zhu
- Department of Biochemistry, and D.O.E. Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Martina Opietnik
- Department of Biochemistry, and D.O.E. Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Nicholas Santoro
- D.O.E. Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, USA
| | - Cliff E Foster
- D.O.E. Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, USA
| | - Fengxia Yue
- Department of Biochemistry, and D.O.E. Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Dino Ress
- Department of Biochemistry, and D.O.E. Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA
| | - Xuejun Pan
- Department of Biological Systems Engineering, University of Wisconsin, Madison, WI, USA
| | - John Ralph
- Department of Biochemistry, and D.O.E. Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI, USA.
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9
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Bevilaqua JM, Finger-Teixeira A, Marchiosi R, Oliveira DMD, Joia BM, Ferro AP, Parizotto ÂV, Dos Santos WD, Ferrarese-Filho O. Exogenous application of rosmarinic acid improves saccharification without affecting growth and lignification of maize. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2019; 142:275-282. [PMID: 31330394 DOI: 10.1016/j.plaphy.2019.07.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 07/11/2019] [Indexed: 06/10/2023]
Abstract
Biomimetically incorporated into the lignin structure, rosmarinic acid improves in vitro maize cell wall saccharification; however, no in planta studies have been performed. We hypothesized that rosmarinic acid, itself, could inducer saccharification without disturbing plant growth. Its effects on growth, enzymes of the phenylpropanoid pathway, lignin, monomeric composition, and saccharification of maize were evaluated. In a short-term (24 h) exposure, rosmarinic acid caused deleterious effects on maize roots, inhibiting the first enzymes of the phenylpropanoid pathway, phenylalanine ammonia-lyase and tyrosine ammonia-lyase, altering lignin composition and slightly increasing saccharification. In a long-term (14 d) exposure, rosmarinic acid increased saccharification of maize stems by about 50% without any deleterious effects on plant growth, the phenylpropanoid pathway and lignin formation. This demonstrated that exogenous application of rosmarinic acid on maize plants improved saccharification, and represented an interesting approach in facilitating enzymatic hydrolysis of biomass polysaccharides and increasing bioethanol production.
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Affiliation(s)
- Jennifer Munik Bevilaqua
- Laboratory of Plant Biochemistry, Department of Biochemistry, University of Maringá, 87020-900, PR, Brazil
| | - Aline Finger-Teixeira
- Laboratory of Plant Biochemistry, Department of Biochemistry, University of Maringá, 87020-900, PR, Brazil
| | - Rogério Marchiosi
- Laboratory of Plant Biochemistry, Department of Biochemistry, University of Maringá, 87020-900, PR, Brazil
| | - Dyoni Matias de Oliveira
- Laboratory of Plant Biochemistry, Department of Biochemistry, University of Maringá, 87020-900, PR, Brazil
| | - Breno Miguel Joia
- Laboratory of Plant Biochemistry, Department of Biochemistry, University of Maringá, 87020-900, PR, Brazil
| | - Ana Paula Ferro
- Laboratory of Plant Biochemistry, Department of Biochemistry, University of Maringá, 87020-900, PR, Brazil
| | | | | | - Osvaldo Ferrarese-Filho
- Laboratory of Plant Biochemistry, Department of Biochemistry, University of Maringá, 87020-900, PR, Brazil.
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OsCAldOMT1 is a bifunctional O-methyltransferase involved in the biosynthesis of tricin-lignins in rice cell walls. Sci Rep 2019; 9:11597. [PMID: 31406182 PMCID: PMC6690965 DOI: 10.1038/s41598-019-47957-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 07/26/2019] [Indexed: 01/26/2023] Open
Abstract
Lignin is a phenylpropanoid polymer produced in the secondary cell walls of vascular plants. Although most eudicot and gymnosperm species generate lignins solely via polymerization of p-hydroxycinnamyl alcohols (monolignols), grasses additionally use a flavone, tricin, as a natural lignin monomer to generate tricin-incorporated lignin polymers in cell walls. We previously found that disruption of a rice 5-HYDROXYCONIFERALDEHYDE O-METHYLTRANSFERASE (OsCAldOMT1) reduced extractable tricin-type metabolites in rice vegetative tissues. This same enzyme has also been implicated in the biosynthesis of sinapyl alcohol, a monolignol that constitutes syringyl lignin polymer units. Here, we further demonstrate through in-depth cell wall structural analyses that OsCAldOMT1-deficient rice plants produce altered lignins largely depleted in both syringyl and tricin units. We also show that recombinant OsCAldOMT1 displayed comparable substrate specificities towards both 5-hydroxyconiferaldehyde and selgin intermediates in the monolignol and tricin biosynthetic pathways, respectively. These data establish OsCAldOMT1 as a bifunctional O-methyltransferase predominantly involved in the two parallel metabolic pathways both dedicated to the biosynthesis of tricin-lignins in rice cell walls. Given that cell wall digestibility was greatly enhanced in the OsCAldOMT1-deficient rice plants, genetic manipulation of CAldOMTs conserved in grasses may serve as a potent strategy to improve biorefinery applications of grass biomass.
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11
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Pazhany AS, Henry RJ. Genetic Modification of Biomass to Alter Lignin Content and Structure. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b01163] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Adhini S. Pazhany
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, 4072 Queensland, Australia
- ICAR - Sugarcane Breeding Institute, Coimbatore, 641 007 Tamil Nadu, India
| | - Robert J. Henry
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, 4072 Queensland, Australia
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12
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Oyarce P, De Meester B, Fonseca F, de Vries L, Goeminne G, Pallidis A, De Rycke R, Tsuji Y, Li Y, Van den Bosch S, Sels B, Ralph J, Vanholme R, Boerjan W. Introducing curcumin biosynthesis in Arabidopsis enhances lignocellulosic biomass processing. NATURE PLANTS 2019; 5:225-237. [PMID: 30692678 DOI: 10.1038/s41477-018-0350-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 12/14/2018] [Indexed: 05/19/2023]
Abstract
Lignin is the main cause of lignocellulosic biomass recalcitrance to industrial enzymatic hydrolysis. By partially replacing the traditional lignin monomers by alternative ones, lignin extractability can be enhanced. To design a lignin that is easier to degrade under alkaline conditions, curcumin (diferuloylmethane) was produced in the model plant Arabidopsis thaliana via simultaneous expression of the turmeric (Curcuma longa) genes DIKETIDE-CoA SYNTHASE (DCS) and CURCUMIN SYNTHASE 2 (CURS2). The transgenic plants produced a plethora of curcumin- and phenylpentanoid-derived compounds with no negative impact on growth. Catalytic hydrogenolysis gave evidence that both curcumin and phenylpentanoids were incorporated into the lignifying cell wall, thereby significantly increasing saccharification efficiency after alkaline pretreatment of the transgenic lines by 14-24% as compared with the wild type. These results demonstrate that non-native monomers can be synthesized and incorporated into the lignin polymer in plants to enhance their biomass processing efficiency.
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Affiliation(s)
- Paula Oyarce
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Barbara De Meester
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Fernando Fonseca
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Lisanne de Vries
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Geert Goeminne
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
- VIB Metabolomics Core, Ghent, Belgium
| | - Andreas Pallidis
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Riet De Rycke
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
- VIB Metabolomics Core, Ghent, Belgium
- Ghent University Expertise Centre for Transmission Electron Microscopy and VIB BioImaging Core, Ghent, Belgium
| | - Yukiko Tsuji
- Department of Biochemistry, University of Wisconsin, Madison, WI, USA
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, WI, USA
| | - Yanding Li
- Department of Biochemistry, University of Wisconsin, Madison, WI, USA
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, WI, USA
| | | | - Bert Sels
- Center for Surface Chemistry and Catalysis, KU Leuven, Heverlee, Belgium
| | - John Ralph
- Department of Biochemistry, University of Wisconsin, Madison, WI, USA
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, WI, USA
| | - Ruben Vanholme
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- VIB Center for Plant Systems Biology, Ghent, Belgium
- VIB Metabolomics Core, Ghent, Belgium
| | - Wout Boerjan
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium.
- VIB Center for Plant Systems Biology, Ghent, Belgium.
- VIB Metabolomics Core, Ghent, Belgium.
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13
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Terrett OM, Dupree P. Covalent interactions between lignin and hemicelluloses in plant secondary cell walls. Curr Opin Biotechnol 2018; 56:97-104. [PMID: 30423528 DOI: 10.1016/j.copbio.2018.10.010] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 10/16/2018] [Accepted: 10/18/2018] [Indexed: 01/21/2023]
Abstract
The plant secondary cell wall is a complex structure composed of polysaccharides and lignin, and is a key evolutionary innovation of vascular land plants. Although cell wall composition is well understood, the cross-linking of the different polymers is only now yielding to investigation. Cross-linking between hemicelluloses and lignin occurs via two different mechanisms: incorporation into lignin by radical coupling of ferulate substitutions on xylan in commelinid monocots, and incorporation of hemicellulosic glycosyl residues by re-aromatisation of lignification intermediates. Recent genetic evidence indicates that hemicellulose:lignin cross-linking has a substantial impact on plant cell wall recalcitrance. Engineering plant biomass with modified frequencies of cross-links will have significant impacts on biomass utilisation.
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Affiliation(s)
- Oliver M Terrett
- Department of Biochemistry, University of Cambridge, Hopkins Building, The Downing Site, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Paul Dupree
- Department of Biochemistry, University of Cambridge, Hopkins Building, The Downing Site, Tennis Court Road, Cambridge CB2 1QW, UK.
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14
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Extraction of arabinoxylan from corncob through modified alkaline method to improve xylooligosaccharides synthesis. ACTA ACUST UNITED AC 2018. [DOI: 10.1016/j.biteb.2018.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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15
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Regner M, Bartuce A, Padmakshan D, Ralph J, Karlen SD. Reductive Cleavage Method for Quantitation of Monolignols and Low-Abundance Monolignol Conjugates. CHEMSUSCHEM 2018; 11:1600-1605. [PMID: 29603658 PMCID: PMC6001451 DOI: 10.1002/cssc.201800617] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Indexed: 05/03/2023]
Abstract
As interest in biomass utilization has grown, the manipulation of lignin biosynthesis has received significant attention, such that recent work has demanded more robust lignin analytical methods. As the derivatization followed by reductive cleavage (DFRC) method is particularly effective for structurally characterizing natively acylated lignins, we used an array of synthetic β-ether γ-acylated model compounds to determine theoretical yields for all monolignol conjugates currently known to exist in lignin, and we synthesized a new set of deuterated analogs as internal standards for quantification using GC-MS/MS. Yields of the saturated ester conjugates ranged from 40 to 90 %, and NMR analysis revealed the presence of residual unsaturated conjugates in yields of 20 to 35 %. In contrast to traditional selected-ion-monitoring, we demonstrated the superior sensitivity and accuracy of multiple-reaction-monitoring detection methods, and further highlighted the inadequacy of traditional standards relative to isotopically labeled analogs.
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Affiliation(s)
- Matt Regner
- DOE Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53726, USA
| | - Allison Bartuce
- DOE Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
| | - Dharshana Padmakshan
- DOE Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
| | - John Ralph
- DOE Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53726, USA
| | - Steven D Karlen
- DOE Great Lakes Bioenergy Research Center, the Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, 53726, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53726, USA
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16
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Tarmadi D, Yoshimura T, Tobimatsu Y, Yamamura M, Umezawa T. Effects of lignins as diet components on the physiological activities of a lower termite, Coptotermes formosanus Shiraki. JOURNAL OF INSECT PHYSIOLOGY 2017; 103:57-63. [PMID: 29038014 DOI: 10.1016/j.jinsphys.2017.10.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 09/25/2017] [Accepted: 10/12/2017] [Indexed: 06/07/2023]
Abstract
We investigated the effects of lignins as diet components on the physiological activities of a lower termite, Coptotermes formosanus Shiraki. Artificial diets composed of polysaccharides with and without purified lignins (milled-wood lignins) from Japanese cedar (softwood), Japanese beech (hardwood), and rice (grass), were fed to C. formosanus workers. The survival and body mass of the workers as well as the presence of three symbiotic protists in the hindguts of the workers were then periodically examined. The survival rates of workers fed on diets containing lignins were, regardless of the lignocellulose diet sources, significantly higher than those of workers fed on only polysaccharides. In addition, it was clearly observed that all the tested lignins have positive effects on the maintenance of two major protists in the hindguts of C. formosanus workers, i.e., Pseudotrichonympha grassii and Holomastigotoides hartmanni. Overall, our data suggest that the presence of lignin is crucial to maintaining the physiological activities of C. formosanus workers during their lignocellulose decomposition. Our data also suggested that some components, possibly minerals and/or non-structural carbohydrates, in grass lignocellulose negatively affect the survival of C. formosanus workers as well as the present rate of the symbiotic protists in their hindguts.
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Affiliation(s)
- Didi Tarmadi
- Laboratory of Innovative Humano-habitability, Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho Uji, Kyoto 611-0011, Japan; Research Center for Biomaterials, Indonesian Institute of Sciences (LIPI), Jl. Raya Bogor KM.46, Cibinong, Bogor, West Java 16911, Indonesia.
| | - Tsuyoshi Yoshimura
- Laboratory of Innovative Humano-habitability, Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho Uji, Kyoto 611-0011, Japan
| | - Yuki Tobimatsu
- Laboratory of Metabolic Science of Forest Plants & Microorganisms, Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho Uji, Kyoto 611-0011, Japan
| | - Masaomi Yamamura
- Laboratory of Metabolic Science of Forest Plants & Microorganisms, Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho Uji, Kyoto 611-0011, Japan
| | - Toshiaki Umezawa
- Laboratory of Metabolic Science of Forest Plants & Microorganisms, Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho Uji, Kyoto 611-0011, Japan
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17
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Lee S, Mo H, Kim JI, Chapple C. Genetic engineering of Arabidopsis to overproduce disinapoyl esters, potential lignin modification molecules. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:40. [PMID: 28239412 PMCID: PMC5316160 DOI: 10.1186/s13068-017-0725-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 02/09/2017] [Indexed: 05/13/2023]
Abstract
BACKGROUND Monolignol-like molecules can be integrated into lignin along with conventional monolignol units, and it has been shown that the incorporation of non-canonical subunits can be used to generate hydrolysable lignin by introduction of ester linkages into the polymer and that this type of lignin is more easily removable. Disinapoyl esters (DSEs), which to some degree resemble the monolignol sinapyl alcohol, may be promising lignin modifying units for this purpose. As a first step toward determining whether this goal is achievable, we manipulated metabolic flux in Arabidopsis to increase the amounts of DSEs by overexpressing sinapoylglucose:sinapoylglucose sinapoyltransferase (SST) which produces two main DSEs, 1,2-disinapoylglucose, and another compound we identify in this report as 3,4-disinapoyl-fructopyranose. RESULTS We succeeded in overproducing DSEs by introducing an SST-overexpression construct into the sinapoylglucose accumulator1 (sng1-6) mutant (SST-OE sng1-6) which lacks several of the enzymes that would otherwise compete for the SST substrate, sinapoyglucose. Introduction of cinnamyl alcohol dehydrogenase-c (cad-c) and cad-d mutations into the SST-OE sng1-6 line further increased DSEs. Surprisingly, a reduced epidermal fluorescence (ref) phenotype was observed when SST-OE sng1-6 plants were evaluated under UV light, which appears to have been induced by the sequestration of DSEs into subvacuolar compartments. Although we successfully upregulated the accumulation of the target DSEs, we did not find any evidence showing the integration of DSEs into the cell wall. CONCLUSIONS Our results suggest that although phenylpropanoid metabolic engineering is possible, a deeper understanding of sequestration and transport mechanisms will be necessary for successful lignin engineering through this route.
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Affiliation(s)
- Shinyoung Lee
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907 USA
- Center for Plant Aging Research, Institute for Basic Science (IBS), Daegu, 711-873 Republic of Korea
| | - Huaping Mo
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907 USA
| | - Jeong Im Kim
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907 USA
| | - Clint Chapple
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907 USA
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18
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Li M, Pu Y, Ragauskas AJ. Current Understanding of the Correlation of Lignin Structure with Biomass Recalcitrance. Front Chem 2016; 4:45. [PMID: 27917379 PMCID: PMC5114238 DOI: 10.3389/fchem.2016.00045] [Citation(s) in RCA: 144] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 11/02/2016] [Indexed: 12/22/2022] Open
Abstract
Lignin, a complex aromatic polymer in terrestrial plants, contributes significantly to biomass recalcitrance to microbial and/or enzymatic deconstruction. To reduce biomass recalcitrance, substantial endeavors have been exerted on pretreatment and lignin engineering in the past few decades. Lignin removal and/or alteration of lignin structure have been shown to result in reduced biomass recalcitrance with improved cell wall digestibility. While high lignin content is usually a barrier to a cost-efficient application of bioresources to biofuels, the direct correlation of lignin structure and its concomitant properties with biomass remains unclear due to the complexity of cell wall and lignin structure. Advancement in application of biorefinery to production of biofuels, chemicals, and bio-derived materials necessitates a fundamental understanding of the relationship of lignin structure and biomass recalcitrance. In this mini-review, we focus on recent investigations on the influence of lignin chemical properties on bioprocessability-pretreatment and enzymatic hydrolysis of biomass. Specifically, lignin-enzyme interactions and the effects of lignin compositional units, hydroxycinnamates, and lignin functional groups on biomass recalcitrance have been highlighted, which will be useful not only in addressing biomass recalcitrance but also in deploying renewable lignocelluloses efficiently.
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Affiliation(s)
- Mi Li
- BioEnergy Science Center, Biosciences Division, Joint Institute of Biological Science, Oak Ridge National Laboratory Oak Ridge, TN, USA
| | - Yunqiao Pu
- BioEnergy Science Center, Biosciences Division, Joint Institute of Biological Science, Oak Ridge National Laboratory Oak Ridge, TN, USA
| | - Arthur J Ragauskas
- BioEnergy Science Center, Biosciences Division, Joint Institute of Biological Science, Oak Ridge National LaboratoryOak Ridge, TN, USA; Department of Chemical and Bimolecular Engineering, University of Tennessee KnoxvilleKnoxville, TN, USA; Department of Forestry, Wildlife, and Fisheries, Center for Renewable Carbon, University Tennessee Institute of AgricultureKnoxville, TN, USA
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19
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Gao R, Lu F, Zhu Y, Hahn MG, Ralph J. Flexible Method for Conjugation of Phenolic Lignin Model Compounds to Carrier Proteins. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:7782-7788. [PMID: 27690421 DOI: 10.1021/acs.jafc.6b04273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Linking lignin model compounds to carrier proteins is required either to raise antibodies to them or to structurally screen antibodies raised against lignins or models. This paper describes a flexible method to link phenolic compounds of interest to cationic bovine serum albumin (cBSA) without interfering with their important structural features. With the guaiacylglycerol-β-guaiacyl ether dimer, for example, the linking was accomplished in 89% yield with the number of dimers per carrier protein being as high as 50; NMR experiments on a 15N- and 13C-labeled conjugation product indicated that 13 dimers were added to the native lysine residues and the remainder (∼37) to the amine moieties on the ethylenediamine linkers added to BSA; ∼32% of the available primary amine groups on cBSA were therefore conjugated to the hapten. This loading is suitable for attempting to raise new antibodies to plant lignins and for screening.
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Affiliation(s)
- Ruili Gao
- Department of Biochemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison , Madison, Wisconsin 53726, United States
| | - Fachuang Lu
- Department of Biochemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison , Madison, Wisconsin 53726, United States
| | - Yimin Zhu
- Department of Chemistry, The Pennsylvania State University , Altoona College, 3000 Ivyside Park, Altoona, Pennsylvania 16601, United States
| | - Michael G Hahn
- Complex Carbohydrate Research Center, The University of Georgia , Athens, Georgia 30602, United States
| | - John Ralph
- Department of Biochemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
- DOE Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin-Madison , Madison, Wisconsin 53726, United States
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20
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Mottiar Y, Vanholme R, Boerjan W, Ralph J, Mansfield SD. Designer lignins: harnessing the plasticity of lignification. Curr Opin Biotechnol 2016; 37:190-200. [DOI: 10.1016/j.copbio.2015.10.009] [Citation(s) in RCA: 214] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 10/14/2015] [Accepted: 10/26/2015] [Indexed: 12/20/2022]
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21
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Bewg WP, Poovaiah C, Lan W, Ralph J, Coleman HD. RNAi downregulation of three key lignin genes in sugarcane improves glucose release without reduction in sugar production. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:270. [PMID: 28031745 PMCID: PMC5168864 DOI: 10.1186/s13068-016-0683-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/06/2016] [Indexed: 05/15/2023]
Abstract
BACKGROUND Sugarcane is a subtropical crop that produces large amounts of biomass annually. It is a key agricultural crop in many countries for the production of sugar and other products. Residual bagasse following sucrose extraction is currently underutilized and it has potential as a carbohydrate source for the production of biofuels. As with all lignocellulosic crops, lignin acts as a barrier to accessing the polysaccharides, and as such, is the focus of transgenic efforts. In this study, we used RNAi to individually reduce the expression of three key genes in the lignin biosynthetic pathway in sugarcane. These genes, caffeoyl-CoA O-methyltransferase (CCoAOMT), ferulate 5-hydroxylase (F5H) and caffeic acid O-methyltransferase (COMT), impact lignin content and/or composition. RESULTS For each RNAi construct, we selected three events for further analysis based on qRT-PCR results. For the CCoAOMT lines, there were no lines with a reduction in lignin content and only one line showed improved glucose release. For F5H, no lines had reduced lignin, but one line had a significant increase in glucose release. For COMT, one line had reduced lignin content, and this line and another released higher levels of glucose during enzymatic hydrolysis. Two of the lines with improved glucose release (F5H-2 and COMT-2) also had reduced S:G ratios. CONCLUSIONS Along with improvements in bagasse quality for the production of lignocellulosic-based fuels, there was only one line with reduction in juice sucrose extraction, and three lines with significantly improved sucrose production, providing evidence that the alteration of sugarcane for improved lignocellulosic ethanol production can be achieved without negatively impacting sugar production and perhaps even enhancing it.
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Affiliation(s)
- William P Bewg
- Queensland University of Technology, Brisbane, QLD 4000 Australia
| | | | - Wu Lan
- Department of Biological Systems Engineering, University of Wisconsin, Madison, WI USA ; US Department of Energy, Great Lakes Bioenergy Research Center (GLBRC), Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53726 USA
| | - John Ralph
- US Department of Energy, Great Lakes Bioenergy Research Center (GLBRC), Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53726 USA ; Department of Biochemistry, University of Wisconsin, Madison, WI 53726 USA
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22
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Le Roy J, Huss B, Creach A, Hawkins S, Neutelings G. Glycosylation Is a Major Regulator of Phenylpropanoid Availability and Biological Activity in Plants. FRONTIERS IN PLANT SCIENCE 2016; 7:735. [PMID: 27303427 PMCID: PMC4880792 DOI: 10.3389/fpls.2016.00735] [Citation(s) in RCA: 203] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Accepted: 05/12/2016] [Indexed: 05/18/2023]
Abstract
The phenylpropanoid pathway in plants is responsible for the biosynthesis of a huge amount of secondary metabolites derived from phenylalanine and tyrosine. Both flavonoids and lignins are synthesized at the end of this very diverse metabolic pathway, as well as many intermediate molecules whose precise biological functions remain largely unknown. The diversity of these molecules can be further increased under the action of UDP-glycosyltransferases (UGTs) leading to the production of glycosylated hydroxycinnamates and related aldehydes, alcohols and esters. Glycosylation can change phenylpropanoid solubility, stability and toxic potential, as well as influencing compartmentalization and biological activity. (De)-glycosylation therefore represents an extremely important regulation point in phenylpropanoid homeostasis. In this article we review recent knowledge on the enzymes involved in regulating phenylpropanoid glycosylation status and availability in different subcellular compartments. We also examine the potential link between monolignol glycosylation and lignification by exploring co-expression of lignin biosynthesis genes and phenolic (de)glycosylation genes. Of the different biological roles linked with their particular chemical properties, phenylpropanoids are often correlated with the plant's stress management strategies that are also regulated by glycosylation. UGTs can for instance influence the resistance of plants during infection by microorganisms and be involved in the mechanisms related to environmental changes. The impact of flavonoid glycosylation on the color of flowers, leaves, seeds and fruits will also be discussed. Altogether this paper underlies the fact that glycosylation and deglycosylation are powerful mechanisms allowing plants to regulate phenylpropanoid localisation, availability and biological activity.
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Tsuji Y, Vanholme R, Tobimatsu Y, Ishikawa Y, Foster CE, Kamimura N, Hishiyama S, Hashimoto S, Shino A, Hara H, Sato-Izawa K, Oyarce P, Goeminne G, Morreel K, Kikuchi J, Takano T, Fukuda M, Katayama Y, Boerjan W, Ralph J, Masai E, Kajita S. Introduction of chemically labile substructures into Arabidopsis lignin through the use of LigD, the Cα-dehydrogenase from Sphingobium sp. strain SYK-6. PLANT BIOTECHNOLOGY JOURNAL 2015; 13:821-32. [PMID: 25580543 DOI: 10.1111/pbi.12316] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Revised: 11/07/2014] [Accepted: 11/25/2014] [Indexed: 05/19/2023]
Abstract
Bacteria-derived enzymes that can modify specific lignin substructures are potential targets to engineer plants for better biomass processability. The Gram-negative bacterium Sphingobium sp. SYK-6 possesses a Cα-dehydrogenase (LigD) enzyme that has been shown to oxidize the α-hydroxy functionalities in β-O-4-linked dimers into α-keto analogues that are more chemically labile. Here, we show that recombinant LigD can oxidize an even wider range of β-O-4-linked dimers and oligomers, including the genuine dilignols, guaiacylglycerol-β-coniferyl alcohol ether and syringylglycerol-β-sinapyl alcohol ether. We explored the possibility of using LigD for biosynthetically engineering lignin by expressing the codon-optimized ligD gene in Arabidopsis thaliana. The ligD cDNA, with or without a signal peptide for apoplast targeting, has been successfully expressed, and LigD activity could be detected in the extracts of the transgenic plants. UPLC-MS/MS-based metabolite profiling indicated that levels of oxidized guaiacyl (G) β-O-4-coupled dilignols and analogues were significantly elevated in the LigD transgenic plants regardless of the signal peptide attachment to LigD. In parallel, 2D NMR analysis revealed a 2.1- to 2.8-fold increased level of G-type α-keto-β-O-4 linkages in cellulolytic enzyme lignins isolated from the stem cell walls of the LigD transgenic plants, indicating that the transformation was capable of altering lignin structure in the desired manner.
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Affiliation(s)
- Yukiko Tsuji
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Ruben Vanholme
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Department of Plant Systems Biology, VIB, Ghent, Belgium
| | - Yuki Tobimatsu
- Department of Biochemistry, University of Wisconsin, Madison, WI, USA
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, WI, USA
| | - Yasuyuki Ishikawa
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Clifton E Foster
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, WI, USA
- Michigan State University, East Lansing, MI, USA
| | - Naofumi Kamimura
- Department of Bioengineering, Nagaoka University of Technology, Niigata, Japan
| | | | - Saki Hashimoto
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Amiu Shino
- Center for Sustainable Resource Science, RIKEN, Kanagawa, Japan
| | - Hirofumi Hara
- Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Kuala Lumpur, Malaysia
| | - Kanna Sato-Izawa
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Paula Oyarce
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Department of Plant Systems Biology, VIB, Ghent, Belgium
| | - Geert Goeminne
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Department of Plant Systems Biology, VIB, Ghent, Belgium
| | - Kris Morreel
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Department of Plant Systems Biology, VIB, Ghent, Belgium
| | - Jun Kikuchi
- Center for Sustainable Resource Science, RIKEN, Kanagawa, Japan
| | | | - Masao Fukuda
- Department of Bioengineering, Nagaoka University of Technology, Niigata, Japan
| | | | - Wout Boerjan
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Department of Plant Systems Biology, VIB, Ghent, Belgium
| | - John Ralph
- Department of Biochemistry, University of Wisconsin, Madison, WI, USA
- US Department of Energy, Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, Madison, WI, USA
| | - Eiji Masai
- Department of Bioengineering, Nagaoka University of Technology, Niigata, Japan
| | - Shinya Kajita
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan
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24
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Vermerris W, Abril A. Enhancing cellulose utilization for fuels and chemicals by genetic modification of plant cell wall architecture. Curr Opin Biotechnol 2014; 32:104-112. [PMID: 25531269 DOI: 10.1016/j.copbio.2014.11.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 11/24/2014] [Accepted: 11/28/2014] [Indexed: 01/10/2023]
Abstract
Cellulose from plant biomass can serve as a sustainable feedstock for fuels, chemicals and polymers that are currently produced from petroleum. In order to enhance economic feasibility, the efficiency of cell wall deconstruction needs to be enhanced. With the use of genetic and biotechnological approaches cell wall composition can be modified in such a way that interactions between the major cell wall polymers—cellulose, hemicellulosic polysaccharides and lignin—are altered. Some of the resulting plants are compromised in their growth and development, but this may be caused in part by the plant's overcompensation for metabolic perturbances. In other cases novel structures have been introduced in the cell wall without negative effects. The first field studies with engineered bioenergy crops look promising, while detailed structural analyses of cellulose synthase offer new opportunities to modify cellulose itself.
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Affiliation(s)
- Wilfred Vermerris
- Department of Microbiology & Cell Science, University of Florida, Gainesville, FL 32611, United States; University of Florida Genetics Institute, University of Florida, Gainesville, FL 32611, United States; Graduate Program in Plant Molecular & Cellular Biology, University of Florida, Gainesville, FL 32611, United States.
| | - Alejandra Abril
- University of Florida Genetics Institute, University of Florida, Gainesville, FL 32611, United States; Graduate Program in Plant Molecular & Cellular Biology, University of Florida, Gainesville, FL 32611, United States
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25
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Diehl BG, Brown NR. Lignin cross-links with cysteine- and tyrosine-containing peptides under biomimetic conditions. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:10312-10319. [PMID: 25275918 DOI: 10.1021/jf503897n] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The work presented here investigates the cross-linking of various nucleophilic amino acids with lignin under aqueous conditions, thus providing insight as to which amino acids might cross-link with lignin in planta. Lignin dehydrogenation polymer (DHP) was prepared in aqueous solutions that contained tripeptides with the general structure XGG, where X represents an amino acid with a nucleophilic side chain. Fourier-transform infrared spectroscopy and energy dispersive X-ray spectroscopy showed that peptides containing cysteine and tyrosine were incorporated into the DHP to form DHP-CGG and DHP-YGG adducts, whereas peptides containing other nucleophilic amino acids were not incorporated. Scanning electron microscopy showed that the physical morphology of DHP was altered by the presence of peptides in the aqueous solution, regardless of peptide incorporation into the DHP. Nuclear magnetic resonance (NMR) spectroscopy showed that cysteine-containing peptide cross-linked with lignin at the lignin α-position, whereas in the case of the lignin-tyrosine adduct the exact cross-linking pathway could not be determined. This is the first study to use NMR to confirm cross-linking between lignin and peptides under biomimetic conditions. The results of this study may indicate the potential for lignin-protein linkage formation in planta, particularly between lignin and cysteine- and/or tyrosine-rich proteins.
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Affiliation(s)
- Brett G Diehl
- Department of Agricultural and Biological Engineering, 226 Forest Resources Building, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
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26
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da Costa RMF, Lee SJ, Allison GG, Hazen SP, Winters A, Bosch M. Genotype, development and tissue-derived variation of cell-wall properties in the lignocellulosic energy crop Miscanthus. ANNALS OF BOTANY 2014; 114:1265-77. [PMID: 24737720 PMCID: PMC4195551 DOI: 10.1093/aob/mcu054] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 02/25/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND AND AIMS Species and hybrids of the genus Miscanthus contain attributes that make them front-runners among current selections of dedicated bioenergy crops. A key trait for plant biomass conversion to biofuels and biomaterials is cell-wall quality; however, knowledge of cell-wall composition and biology in Miscanthus species is limited. This study presents data on cell-wall compositional changes as a function of development and tissue type across selected genotypes, and considers implications for the development of miscanthus as a sustainable and renewable bioenergy feedstock. METHODS Cell-wall biomass was analysed for 25 genotypes, considering different developmental stages and stem vs. leaf compositional variability, by Fourier transform mid-infrared spectroscopy and lignin determination. In addition, a Clostridium phytofermentans bioassay was used to assess cell-wall digestibility and conversion to ethanol. KEY RESULTS Important cell-wall compositional differences between miscanthus stem and leaf samples were found to be predominantly associated with structural carbohydrates. Lignin content increased as plants matured and was higher in stem tissues. Although stem lignin concentration correlated inversely with ethanol production, no such correlation was observed for leaves. Leaf tissue contributed significantly to total above-ground biomass at all stages, although the extent of this contribution was genotype-dependent. CONCLUSIONS It is hypothesized that divergent carbohydrate compositions and modifications in stem and leaf tissues are major determinants for observed differences in cell-wall quality. The findings indicate that improvement of lignocellulosic feedstocks should encompass tissue-dependent variation as it affects amenability to biological conversion. For gene-trait associations relating to cell-wall quality, the data support the separate examination of leaf and stem composition, as tissue-specific traits may be masked by considering only total above-ground biomass samples, and sample variability could be mostly due to varying tissue contributions to total biomass.
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Affiliation(s)
- Ricardo M F da Costa
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Plas Gogerddan, Aberystwyth, Ceredigion, SY23 3EB, UK
| | - Scott J Lee
- Biology Department, University of Massachusetts, Amherst, MA, USA Plant Biology Graduate Program, University of Massachusetts, Amherst, MA, USA
| | - Gordon G Allison
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Plas Gogerddan, Aberystwyth, Ceredigion, SY23 3EB, UK
| | - Samuel P Hazen
- Biology Department, University of Massachusetts, Amherst, MA, USA
| | - Ana Winters
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Plas Gogerddan, Aberystwyth, Ceredigion, SY23 3EB, UK
| | - Maurice Bosch
- Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Plas Gogerddan, Aberystwyth, Ceredigion, SY23 3EB, UK
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27
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Biochemical properties and atomic resolution structure of a proteolytically processed β-mannanase from cellulolytic Streptomyces sp. SirexAA-E. PLoS One 2014; 9:e94166. [PMID: 24710170 PMCID: PMC3978015 DOI: 10.1371/journal.pone.0094166] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 03/11/2014] [Indexed: 01/07/2023] Open
Abstract
β-Mannanase SACTE_2347 from cellulolytic Streptomyces sp. SirexAA-E is abundantly secreted into the culture medium during growth on cellulosic materials. The enzyme is composed of domains from the glycoside hydrolase family 5 (GH5), fibronectin type-III (Fn3), and carbohydrate binding module family 2 (CBM2). After secretion, the enzyme is proteolyzed into three different, catalytically active variants with masses of 53, 42 and 34 kDa corresponding to the intact protein, loss of the CBM2 domain, or loss of both the Fn3 and CBM2 domains. The three variants had identical N-termini starting with Ala51, and the positions of specific proteolytic reactions in the linker sequences separating the three domains were identified. To conduct biochemical and structural characterizations, the natural proteolytic variants were reproduced by cloning and heterologously expressed in Escherichia coli. Each SACTE_2347 variant hydrolyzed only β-1,4 mannosidic linkages, and also reacted with pure mannans containing partial galactosyl- and/or glucosyl substitutions. Examination of the X-ray crystal structure of the GH5 domain of SACTE_2347 suggests that two loops adjacent to the active site channel, which have differences in position and length relative to other closely related mannanases, play a role in producing the observed substrate selectivity.
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28
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Lignin bioengineering. Curr Opin Biotechnol 2014; 26:189-98. [DOI: 10.1016/j.copbio.2014.01.002] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 12/24/2013] [Accepted: 01/06/2014] [Indexed: 01/08/2023]
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29
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Disruption of Mediator rescues the stunted growth of a lignin-deficient Arabidopsis mutant. Nature 2014; 509:376-80. [PMID: 24670657 DOI: 10.1038/nature13084] [Citation(s) in RCA: 226] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 01/27/2014] [Indexed: 12/19/2022]
Abstract
Lignin is a phenylpropanoid-derived heteropolymer important for the strength and rigidity of the plant secondary cell wall. Genetic disruption of lignin biosynthesis has been proposed as a means to improve forage and bioenergy crops, but frequently results in stunted growth and developmental abnormalities, the mechanisms of which are poorly understood. Here we show that the phenotype of a lignin-deficient Arabidopsis mutant is dependent on the transcriptional co-regulatory complex, Mediator. Disruption of the Mediator complex subunits MED5a (also known as REF4) and MED5b (also known as RFR1) rescues the stunted growth, lignin deficiency and widespread changes in gene expression seen in the phenylpropanoid pathway mutant ref8, without restoring the synthesis of guaiacyl and syringyl lignin subunits. Cell walls of rescued med5a/5b ref8 plants instead contain a novel lignin consisting almost exclusively of p-hydroxyphenyl lignin subunits, and moreover exhibit substantially facilitated polysaccharide saccharification. These results demonstrate that guaiacyl and syringyl lignin subunits are largely dispensable for normal growth and development, implicate Mediator in an active transcriptional process responsible for dwarfing and inhibition of lignin biosynthesis, and suggest that the transcription machinery and signalling pathways responding to cell wall defects may be important targets to include in efforts to reduce biomass recalcitrance.
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30
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Sorek N, Yeats TH, Szemenyei H, Youngs H, Somerville CR. The Implications of Lignocellulosic Biomass Chemical Composition for the Production of Advanced Biofuels. Bioscience 2014. [DOI: 10.1093/biosci/bit037] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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31
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Tobimatsu Y, Wouwer DVD, Allen E, Kumpf R, Vanholme B, Boerjan W, Ralph J. A click chemistry strategy for visualization of plant cell wall lignification. Chem Commun (Camb) 2014; 50:12262-5. [DOI: 10.1039/c4cc04692g] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Monolignol mimics bearing chemical reporter tags and bioorthogonal click chemistry were commissioned to visualize plant cell wall lignins in vivo.
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Affiliation(s)
- Yuki Tobimatsu
- Department of Biochemistry and the US Department of Energy's Great Lakes Bioenergy Research Center (GLBRC)
- the Wisconsin Energy Institute
- University of Wisconsin
- Madison, USA
| | - Dorien Van de Wouwer
- Department of Plant Systems Biology
- VIB
- Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics
- Ghent University
| | - Eric Allen
- Department of Biochemistry and the US Department of Energy's Great Lakes Bioenergy Research Center (GLBRC)
- the Wisconsin Energy Institute
- University of Wisconsin
- Madison, USA
| | - Robert Kumpf
- Department of Plant Systems Biology
- VIB
- Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics
- Ghent University
| | - Bartel Vanholme
- Department of Plant Systems Biology
- VIB
- Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics
- Ghent University
| | - Wout Boerjan
- Department of Plant Systems Biology
- VIB
- Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics
- Ghent University
| | - John Ralph
- Department of Biochemistry and the US Department of Energy's Great Lakes Bioenergy Research Center (GLBRC)
- the Wisconsin Energy Institute
- University of Wisconsin
- Madison, USA
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32
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Tobimatsu Y, Wagner A, Donaldson L, Mitra P, Niculaes C, Dima O, Kim JI, Anderson N, Loque D, Boerjan W, Chapple C, Ralph J. Visualization of plant cell wall lignification using fluorescence-tagged monolignols. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 76:357-66. [PMID: 23889038 PMCID: PMC4238399 DOI: 10.1111/tpj.12299] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 06/19/2013] [Accepted: 07/18/2013] [Indexed: 05/15/2023]
Abstract
Lignin is an abundant phenylpropanoid polymer produced by the oxidative polymerization of p-hydroxycinnamyl alcohols (monolignols). Lignification, i.e., deposition of lignin, is a defining feature of secondary cell wall formation in vascular plants, and provides an important mechanism for their disease resistance; however, many aspects of the cell wall lignification process remain unclear partly because of a lack of suitable imaging methods to monitor the process in vivo. In this study, a set of monolignol analogs γ-linked to fluorogenic aminocoumarin and nitrobenzofuran dyes were synthesized and tested as imaging probes to visualize the cell wall lignification process in Arabidopsis thaliana and Pinus radiata under various feeding regimens. In particular, we demonstrate that the fluorescence-tagged monolignol analogs can penetrate into live plant tissues and cells, and appear to be metabolically incorporated into lignifying cell walls in a highly specific manner. The localization of the fluorogenic lignins synthesized during the feeding period can be readily visualized by fluorescence microscopy and is distinguishable from the other wall components such as polysaccharides as well as the pre-existing lignin that was deposited earlier in development.
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Affiliation(s)
- Yuki Tobimatsu
- Department of Biochemistry and the US Department of Energy’s Great Lakes Bioenergy Research Center (GLBRC), the Wisconsin Energy Institute, University of Wisconsin1552 University Avenue, Madison, WI, 53726, USA
- *For correspondence (e-mails ; )
| | | | | | - Prajakta Mitra
- The US Department of Energy’s Joint BioEnergy Institute (JBEI), Physical Bioscience Division, Lawrence Berkeley National Laboratory5885 Hollis St, Emeryville, CA, 94608, USA
| | - Claudiu Niculaes
- Department of Plant Systems Biology, VIBTechnologiepark 927, B-9052 Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent UniversityTechnologiepark 927, B-9052 Gent, Belgium
| | - Oana Dima
- Department of Plant Systems Biology, VIBTechnologiepark 927, B-9052 Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent UniversityTechnologiepark 927, B-9052 Gent, Belgium
| | - Jeong Im Kim
- Department of Biochemistry, Purdue University175 South University Street, West Lafayette, IN, 47907, USA
| | - Nickolas Anderson
- Department of Biochemistry, Purdue University175 South University Street, West Lafayette, IN, 47907, USA
| | - Dominique Loque
- The US Department of Energy’s Joint BioEnergy Institute (JBEI), Physical Bioscience Division, Lawrence Berkeley National Laboratory5885 Hollis St, Emeryville, CA, 94608, USA
| | - Wout Boerjan
- Department of Plant Systems Biology, VIBTechnologiepark 927, B-9052 Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent UniversityTechnologiepark 927, B-9052 Gent, Belgium
| | - Clint Chapple
- Department of Biochemistry, Purdue University175 South University Street, West Lafayette, IN, 47907, USA
| | - John Ralph
- Department of Biochemistry and the US Department of Energy’s Great Lakes Bioenergy Research Center (GLBRC), the Wisconsin Energy Institute, University of Wisconsin1552 University Avenue, Madison, WI, 53726, USA
- *For correspondence (e-mails ; )
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Wang C, Qian C, Roman M, Glasser WG, Esker AR. Surface-Initiated Dehydrogenative Polymerization of Monolignols: A Quartz Crystal Microbalance with Dissipation Monitoring and Atomic Force Microscopy Study. Biomacromolecules 2013; 14:3964-72. [DOI: 10.1021/bm401084h] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Chao Wang
- Departments of †Chemistry and ‡Sustainable Biomaterials, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Chen Qian
- Departments of †Chemistry and ‡Sustainable Biomaterials, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Maren Roman
- Departments of †Chemistry and ‡Sustainable Biomaterials, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Wolfgang G. Glasser
- Departments of †Chemistry and ‡Sustainable Biomaterials, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Alan R. Esker
- Departments of †Chemistry and ‡Sustainable Biomaterials, Virginia Tech, Blacksburg, Virginia 24061, United States
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34
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Wang Y, Chantreau M, Sibout R, Hawkins S. Plant cell wall lignification and monolignol metabolism. FRONTIERS IN PLANT SCIENCE 2013; 4:220. [PMID: 23847630 PMCID: PMC3705174 DOI: 10.3389/fpls.2013.00220] [Citation(s) in RCA: 169] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 06/06/2013] [Indexed: 05/18/2023]
Abstract
Plants are built of various specialized cell types that differ in their cell wall composition and structure. The cell walls of certain tissues (xylem, sclerenchyma) are characterized by the presence of the heterogeneous lignin polymer that plays an essential role in their physiology. This phenolic polymer is composed of different monomeric units - the monolignols - that are linked together by several covalent bonds. Numerous studies have shown that monolignol biosynthesis and polymerization to form lignin are tightly controlled in different cell types and tissues. However, our understanding of the genetic control of monolignol transport and polymerization remains incomplete, despite some recent promising results. This situation is made more complex since we know that monolignols or related compounds are sometimes produced in non-lignified tissues. In this review, we focus on some key steps of monolignol metabolism including polymerization, transport, and compartmentation. As well as being of fundamental interest, the quantity of lignin and its nature are also known to have a negative effect on the industrial processing of plant lignocellulose biomass. A more complete view of monolignol metabolism and the relationship that exists between lignin and other monolignol-derived compounds thereby appears essential if we wish to improve biomass quality.
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Affiliation(s)
- Yin Wang
- Unite Mixte de Recherche 1318, Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, Saclay Plant SciencesVersailles, France
| | - Maxime Chantreau
- Lille 1 UMR 1281, UniversitéLille Nord de FranceVilleneuve d’Ascq, France
- Unite Mixte de Recherche 1281, Stress Abiotiques et Différenciation des Végétaux Cultivés, Institut National de la Recherche AgronomiqueVilleneuve d’Ascq, France
| | - Richard Sibout
- Unite Mixte de Recherche 1318, Institut Jean-Pierre Bourgin, Institut National de la Recherche Agronomique, Saclay Plant SciencesVersailles, France
| | - Simon Hawkins
- Lille 1 UMR 1281, UniversitéLille Nord de FranceVilleneuve d’Ascq, France
- Unite Mixte de Recherche 1281, Stress Abiotiques et Différenciation des Végétaux Cultivés, Institut National de la Recherche AgronomiqueVilleneuve d’Ascq, France
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35
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Bianchetti CM, Harmann CH, Takasuka TE, Hura GL, Dyer K, Fox BG. Fusion of dioxygenase and lignin-binding domains in a novel secreted enzyme from cellulolytic Streptomyces sp. SirexAA-E. J Biol Chem 2013; 288:18574-87. [PMID: 23653358 PMCID: PMC3689997 DOI: 10.1074/jbc.m113.475848] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 05/03/2013] [Indexed: 11/06/2022] Open
Abstract
Streptomyces sp. SirexAA-E is a highly cellulolytic bacterium isolated from an insect/microbe symbiotic community. When grown on lignin-containing biomass, it secretes SACTE_2871, an aromatic ring dioxygenase domain fused to a family 5/12 carbohydrate-binding module (CBM 5/12). Here we present structural and catalytic studies of this novel fusion enzyme, thus providing insight into its function. The dioxygenase domain has the core β-sandwich fold typical of this enzyme family but lacks a dimerization domain observed in other intradiol dioxygenases. Consequently, the x-ray structure shows that the enzyme is monomeric and the Fe(III)-containing active site is exposed to solvent in a shallow depression on a planar surface. Purified SACTE_2871 catalyzes the O2-dependent intradiol cleavage of catechyl compounds from lignin biosynthetic pathways, but not their methylated derivatives. Binding studies show that SACTE_2871 binds synthetic lignin polymers and chitin through the interactions of the CBM 5/12 domain, representing a new binding specificity for this fold-family. Based on its unique structural features and functional properties, we propose that SACTE_2871 contributes to the invasive nature of the insect/microbial community by destroying precursors needed by the plant for de novo lignin biosynthesis as part of its natural wounding response.
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Affiliation(s)
- Christopher M. Bianchetti
- From the Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, 53706 and
| | - Connor H. Harmann
- From the Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, 53706 and
| | - Taichi E. Takasuka
- From the Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, 53706 and
| | - Gregory L. Hura
- the Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Kevin Dyer
- the Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Brian G. Fox
- From the Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, Wisconsin, 53706 and
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Vanholme R, Morreel K, Darrah C, Oyarce P, Grabber JH, Ralph J, Boerjan W. Metabolic engineering of novel lignin in biomass crops. THE NEW PHYTOLOGIST 2012; 196:978-1000. [PMID: 23035778 DOI: 10.1111/j.1469-8137.2012.04337.x] [Citation(s) in RCA: 198] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Accepted: 08/08/2012] [Indexed: 05/17/2023]
Abstract
Lignin, a phenolic polymer in the secondary wall, is the major cause of lignocellulosic biomass recalcitrance to efficient industrial processing. From an applications perspective, it is desirable that second-generation bioenergy crops have lignin that is readily degraded by chemical pretreatments but still fulfill its biological role in plants. Because plants can tolerate large variations in lignin composition, often without apparent adverse effects, substitution of some fraction of the traditional monolignols by alternative monomers through genetic engineering is a promising strategy to tailor lignin in bioenergy crops. However, successful engineering of lignin incorporating alternative monomers requires knowledge about phenolic metabolism in plants and about the coupling properties of these alternative monomers. Here, we review the current knowledge about lignin biosynthesis and the pathways towards the main phenolic classes. In addition, the minimal requirements are defined for molecules that, upon incorporation into the lignin polymer, make the latter more susceptible to biomass pretreatment. Numerous metabolites made by plants meet these requirements, and several have already been tested as monolignol substitutes in biomimetic systems. Finally, the status of detection and identification of compounds by phenolic profiling is discussed, as phenolic profiling serves in pathway elucidation and for the detection of incorporation of alternative lignin monomers.
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Affiliation(s)
- Ruben Vanholme
- Department of Plant Systems Biology, VIB, Technologiepark 927, 9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052, Gent, Belgium
| | - Kris Morreel
- Department of Plant Systems Biology, VIB, Technologiepark 927, 9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052, Gent, Belgium
| | - Chiarina Darrah
- Department of Plant Systems Biology, VIB, Technologiepark 927, 9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052, Gent, Belgium
| | - Paula Oyarce
- Department of Plant Systems Biology, VIB, Technologiepark 927, 9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052, Gent, Belgium
| | - John H Grabber
- USDA-Agricultural Research Service, US Dairy Forage Research Center, 1925 Linden Drive West, Madison, WI, 53706, USA
| | - John Ralph
- Departments of Biochemistry and Biological Systems Engineering, the Wisconsin Bioenergy Initiative, and the DOE Great Lakes Bioenergy Research Center, University of Wisconsin, 433 Babcock Drive, Madison, WI, 53706, USA
| | - Wout Boerjan
- Department of Plant Systems Biology, VIB, Technologiepark 927, 9052, Gent, Belgium
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Technologiepark 927, 9052, Gent, Belgium
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Elumalai S, Tobimatsu Y, Grabber JH, Pan X, Ralph J. Epigallocatechin gallate incorporation into lignin enhances the alkaline delignification and enzymatic saccharification of cell walls. BIOTECHNOLOGY FOR BIOFUELS 2012; 5:59. [PMID: 22889353 PMCID: PMC3477100 DOI: 10.1186/1754-6834-5-59] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 08/06/2012] [Indexed: 05/02/2023]
Abstract
BACKGROUND Lignin is an integral component of the plant cell wall matrix but impedes the conversion of biomass into biofuels. The plasticity of lignin biosynthesis should permit the inclusion of new compatible phenolic monomers such as flavonoids into cell wall lignins that are consequently less recalcitrant to biomass processing. In the present study, epigallocatechin gallate (EGCG) was evaluated as a potential lignin bioengineering target for rendering biomass more amenable to processing for biofuel production. RESULTS In vitro peroxidase-catalyzed polymerization experiments revealed that both gallate and pyrogallyl (B-ring) moieties in EGCG underwent radical cross-coupling with monolignols mainly by β-O-4-type cross-coupling, producing benzodioxane units following rearomatization reactions. Biomimetic lignification of maize cell walls with a 3:1 molar ratio of monolignols and EGCG permitted extensive alkaline delignification of cell walls (72 to 92%) that far exceeded that for lignified controls (44 to 62%). Alkali-insoluble residues from EGCG-lignified walls yielded up to 34% more glucose and total sugars following enzymatic saccharification than lignified controls. CONCLUSIONS It was found that EGCG readily copolymerized with monolignols to become integrally cross-coupled into cell wall lignins, where it greatly enhanced alkaline delignification and subsequent enzymatic saccharification. Improved delignification may be attributed to internal trapping of quinone-methide intermediates to prevent benzyl ether cross-linking of lignin to structural polysaccharides during lignification, and to the cleavage of ester intra-unit linkages within EGCG during pretreatment. Overall, our results suggest that apoplastic deposition of EGCG for incorporation into lignin would be a promising plant genetic engineering target for improving the delignification and saccharification of biomass crops.
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Affiliation(s)
- Sasikumar Elumalai
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, WI, 53706, USA
| | - Yuki Tobimatsu
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI, 53706, USA
| | - John H Grabber
- U.S. Dairy Forage Research Center, USDA-Agricultural Research Service, 1925 Linden Drive West, Madison, WI, 53706, USA
| | - Xuejun Pan
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, WI, 53706, USA
| | - John Ralph
- Department of Biological Systems Engineering, University of Wisconsin-Madison, 460 Henry Mall, Madison, WI, 53706, USA
- Department of Biochemistry, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI, 53706, USA
- DOE Great Lakes Bioenergy Research Center, and Wisconsin Bioenergy Initiative, University of Wisconsin-Madison, Madison, WI, 53706, USA
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Grabber JH, Ress D, Ralph J. Identifying new lignin bioengineering targets: impact of epicatechin, quercetin glycoside, and gallate derivatives on the lignification and fermentation of maize cell walls. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2012; 60:5152-60. [PMID: 22475000 DOI: 10.1021/jf203986a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Apoplastic targeting of secondary metabolites compatible with monolignol polymerization may provide new avenues for designing lignins that are less inhibitory toward fiber fermentation. To identify suitable monolignol substitutes, primary maize cell walls were artificially lignified with normal monolignols plus various epicatechin, quercetin glycoside, and gallate derivatives added as 0 or 45% by weight of the precursor mixture. The flavonoids and gallates had variable effects on peroxidase activity, but all dropped lignification pH. Epigallocatechin gallate, epicatechin gallate, epicatechin vanillate, epigallocatechin, galloylhyperin, and pentagalloylglucose formed wall-bound lignin at moderate to high concentrations, and their incorporation increased 48 h in vitro ruminal fiber fermentability by 20-33% relative to lignified controls. By contrast, ethyl gallate and corilagin severely depressed lignification and increased 48 h fermentability by about 50%. The results suggest several flavonoid and gallate derivatives are promising lignin bioengineering targets for improving the inherent fermentability of nonpretreated cell walls.
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Affiliation(s)
- John H Grabber
- U.S. Dairy Forage Research Center, Agricultural Research Service, U.S. Department of Agriculture , 1925 Linden Drive West, Madison, Wisconsin 53706, USA.
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