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Yang D, Liu H, Li X, Zhang Y, Zhang X, Yang H, Liu M, Koch KE, McCarty DR, Li S, Tan BC. A sucrose ferulate cycle linchpin for ferulyolation of arabinoxylans in plant commelinids. NATURE PLANTS 2024; 10:1389-1399. [PMID: 39232219 DOI: 10.1038/s41477-024-01781-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 08/01/2024] [Indexed: 09/06/2024]
Abstract
A transformation in plant cell wall evolution marked the emergence of grasses, grains and related species that now cover much of the globe. Their tough, less digestible cell walls arose from a new pattern of cross-linking between arabinoxylan polymers with distinctive ferulic acid residues. Despite extensive study, the biochemical mechanism of ferulic acid incorporation into cell walls remains unknown. Here we show that ferulic acid is transferred to arabinoxylans via an unexpected sucrose derivative, 3,6-O-diferuloyl sucrose (2-feruloyl-O-α-D-glucopyranosyl-(1'→2)-3,6-O-feruloyl-β-D-fructofuranoside), formed by a sucrose ferulate cycle. Sucrose gains ferulate units through sequential transfers from feruloyl-CoA, initially at the O-3 position of sucrose catalysed by a family of BAHD-type sucrose ferulic acid transferases (SFT1 to SFT4 in maize), then at the O-6 position by a feruloyl sucrose feruloyl transferase (FSFT), which creates 3,6-O-diferuloyl sucrose. An FSFT-deficient mutant of maize, disorganized wall 1 (dow1), sharply decreases cell wall arabinoxylan ferulic acid content, causes accumulation of 3-O-feruloyl sucrose (α-D-glucopyranosyl-(1'→2)-3-O-feruloyl-β-D-fructofuranoside) and leads to the abortion of embryos with defective cell walls. In vivo, isotope-labelled ferulic acid residues are transferred from 3,6-O-diferuloyl sucrose onto cell wall arabinoxylans. This previously unrecognized sucrose ferulate cycle resolves a long-standing mystery surrounding the evolution of the distinctive cell wall characteristics of cereal grains, biofuel crops and related commelinid species; identifies an unexpected role for sucrose as a ferulate group carrier in cell wall biosynthesis; and reveals a new paradigm for modifying cell wall polymers through ferulic acid incorporation.
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Affiliation(s)
- Dalin Yang
- Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, China
| | - Hui Liu
- Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, China
| | - Xiaojie Li
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Yafeng Zhang
- Guangdong Provincial Key Laboratory of Plant Molecular Breeding, College of Agriculture, South China Agricultural University, Guangzhou, China
| | - Xingwang Zhang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Huanhuan Yang
- School of Life Sciences, Qilu Normal University, Jinan, China
| | - Mingyu Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Karen E Koch
- Hoirticultural Sciences Department, University of Florida, Gainesville, FL, USA
| | - Donald R McCarty
- Hoirticultural Sciences Department, University of Florida, Gainesville, FL, USA
| | - Shengying Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Bao-Cai Tan
- Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, China.
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2
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Zhong R, Phillips DR, Clark KD, Adams ER, Lee C, Ye ZH. Biochemical Characterization of Rice Xylan Biosynthetic Enzymes in Determining Xylan Chain Elongation and Substitutions. PLANT & CELL PHYSIOLOGY 2024; 65:1065-1079. [PMID: 38501734 DOI: 10.1093/pcp/pcae028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 03/05/2024] [Accepted: 03/18/2024] [Indexed: 03/20/2024]
Abstract
Grass xylan consists of a linear chain of β-1,4-linked xylosyl residues that often form domains substituted only with either arabinofuranose (Araf) or glucuronic acid (GlcA)/methylglucuronic acid (MeGlcA) residues, and it lacks the unique reducing end tetrasaccharide sequence found in dicot xylan. The mechanism of how grass xylan backbone elongation is initiated and how its distinctive substitution pattern is determined remains elusive. Here, we performed biochemical characterization of rice xylan biosynthetic enzymes, including xylan synthases, glucuronyltransferases and methyltransferases. Activity assays of rice xylan synthases demonstrated that they required short xylooligomers as acceptors for their activities. While rice xylan glucuronyltransferases effectively glucuronidated unsubstituted xylohexaose acceptors, they transferred little GlcA residues onto (Araf)-substituted xylohexaoses and rice xylan 3-O-arabinosyltransferase could not arabinosylate GlcA-substituted xylohexaoses, indicating that their intrinsic biochemical properties may contribute to the distinctive substitution patterns of rice xylan. In addition, we found that rice xylan methyltransferase exhibited a low substrate binding affinity, which may explain the partial GlcA methylation in rice xylan. Furthermore, immunolocalization of xylan in xylem cells of both rice and Arabidopsis showed that it was deposited together with cellulose in secondary walls without forming xylan-rich nanodomains. Together, our findings provide new insights into the biochemical mechanisms underlying xylan backbone elongation and substitutions in grass species.
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Affiliation(s)
- Ruiqin Zhong
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Dennis R Phillips
- Department of Chemistry, University of Georgia, Athens, GA 30602, USA
| | - Kevin D Clark
- Department of Chemistry, University of Georgia, Athens, GA 30602, USA
| | - Earle R Adams
- Department of Chemistry, University of Georgia, Athens, GA 30602, USA
| | - Chanhui Lee
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
- Department of Plant & Environmental New Resources, College of Life Sciences, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Zheng-Hua Ye
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
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Wang Z, Wu J, Kong W, Zhou Y, Ye C, Yuan Q, Zhang Y, Li P. The Integration of Transcriptome and Metabolome Analyses Provides Insights into the Determinants of the Wood Properties in Toona ciliata. Int J Mol Sci 2024; 25:4541. [PMID: 38674126 PMCID: PMC11050501 DOI: 10.3390/ijms25084541] [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: 02/23/2024] [Revised: 04/15/2024] [Accepted: 04/18/2024] [Indexed: 04/28/2024] Open
Abstract
Toona ciliata, also known as Chinese mahogany, is a high-quality and fast-growing wood species with a high economic value. The wood properties of T. ciliata of different provenances vary significantly. In this study, we conducted comprehensive transcriptome and metabolome analyses of red and non-red T. ciliata wood cores of different provenances to compare their wood properties and explore the differential metabolites and genes that govern the variation in their wood properties. Through combined analyses, three differential genes and two metabolites were identified that are possibly related to lignin synthesis. The lignin content in wood cores from T. ciliata of different provenances shows significant variation following systematic measurement and comparisons. The gene Tci09G002190, one of the three differential genes, was identified as a member of the CAD (Cinnamyl alcohol dehydrogenase) gene family of T. ciliata, which is associated with lignin synthesis. Our data provide insights into the determinants of the wood properties in T. ciliata, providing a solid foundation for research into the subsequent mechanisms of the formation of T. ciliata wood.
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Affiliation(s)
- Zhi Wang
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China; (Z.W.); (J.W.); (W.K.); (Y.Z.); (C.Y.); (Q.Y.); (Y.Z.)
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, Guangzhou 510642, China
| | - Jinsong Wu
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China; (Z.W.); (J.W.); (W.K.); (Y.Z.); (C.Y.); (Q.Y.); (Y.Z.)
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, Guangzhou 510642, China
| | - Weijia Kong
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China; (Z.W.); (J.W.); (W.K.); (Y.Z.); (C.Y.); (Q.Y.); (Y.Z.)
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, Guangzhou 510642, China
| | - Yu Zhou
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China; (Z.W.); (J.W.); (W.K.); (Y.Z.); (C.Y.); (Q.Y.); (Y.Z.)
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, Guangzhou 510642, China
| | - Chunyi Ye
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China; (Z.W.); (J.W.); (W.K.); (Y.Z.); (C.Y.); (Q.Y.); (Y.Z.)
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, Guangzhou 510642, China
| | - Qianyun Yuan
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China; (Z.W.); (J.W.); (W.K.); (Y.Z.); (C.Y.); (Q.Y.); (Y.Z.)
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, Guangzhou 510642, China
| | - Yongjia Zhang
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China; (Z.W.); (J.W.); (W.K.); (Y.Z.); (C.Y.); (Q.Y.); (Y.Z.)
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, Guangzhou 510642, China
| | - Pei Li
- College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou 510642, China; (Z.W.); (J.W.); (W.K.); (Y.Z.); (C.Y.); (Q.Y.); (Y.Z.)
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, Guangzhou 510642, China
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Peracchi LM, Panahabadi R, Barros-Rios J, Bartley LE, Sanguinet KA. Grass lignin: biosynthesis, biological roles, and industrial applications. FRONTIERS IN PLANT SCIENCE 2024; 15:1343097. [PMID: 38463570 PMCID: PMC10921064 DOI: 10.3389/fpls.2024.1343097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/06/2024] [Indexed: 03/12/2024]
Abstract
Lignin is a phenolic heteropolymer found in most terrestrial plants that contributes an essential role in plant growth, abiotic stress tolerance, and biotic stress resistance. Recent research in grass lignin biosynthesis has found differences compared to dicots such as Arabidopsis thaliana. For example, the prolific incorporation of hydroxycinnamic acids into grass secondary cell walls improve the structural integrity of vascular and structural elements via covalent crosslinking. Conversely, fundamental monolignol chemistry conserves the mechanisms of monolignol translocation and polymerization across the plant phylum. Emerging evidence suggests grass lignin compositions contribute to abiotic stress tolerance, and periods of biotic stress often alter cereal lignin compositions to hinder pathogenesis. This same recalcitrance also inhibits industrial valorization of plant biomass, making lignin alterations and reductions a prolific field of research. This review presents an update of grass lignin biosynthesis, translocation, and polymerization, highlights how lignified grass cell walls contribute to plant development and stress responses, and briefly addresses genetic engineering strategies that may benefit industrial applications.
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Affiliation(s)
- Luigi M. Peracchi
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
| | - Rahele Panahabadi
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States
| | - Jaime Barros-Rios
- Division of Plant Sciences and Interdisciplinary Plant Group, University of Missouri, Columbia, MO, United States
| | - Laura E. Bartley
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States
| | - Karen A. Sanguinet
- Department of Crop and Soil Sciences, Washington State University, Pullman, WA, United States
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5
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Lam LPY, Tobimatsu Y, Suzuki S, Tanaka T, Yamamoto S, Takeda-Kimura Y, Osakabe Y, Osakabe K, Ralph J, Bartley LE, Umezawa T. Disruption of p-coumaroyl-CoA:monolignol transferases in rice drastically alters lignin composition. PLANT PHYSIOLOGY 2024; 194:832-848. [PMID: 37831082 DOI: 10.1093/plphys/kiad549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 09/28/2023] [Accepted: 09/28/2023] [Indexed: 10/14/2023]
Abstract
Grasses are abundant feedstocks that can supply lignocellulosic biomass for production of cell-wall-derived chemicals. In grass cell walls, lignin is acylated with p-coumarate. These p-coumarate decorations arise from the incorporation of monolignol p-coumarate conjugates during lignification. A previous biochemical study identified a rice (Oryza sativa) BAHD acyltransferase (AT) with p-coumaroyl-CoA:monolignol transferase (PMT) activity in vitro. In this study, we determined that that enzyme, which we name OsPMT1 (also known as OsAT4), and the closely related OsPMT2 (OsAT3) harbor similar catalytic activity toward monolignols. We generated rice mutants deficient in either or both OsPMT1 and OsPMT2 by CRISPR/Cas9-mediated mutagenesis and subjected the mutants' cell walls to analysis using chemical and nuclear magnetic resonance methods. Our results demonstrated that OsPMT1 and OsPMT2 both function in lignin p-coumaroylation in the major vegetative tissues of rice. Notably, lignin-bound p-coumarate units were undetectable in the ospmt1 ospmt2-2 double-knockout mutant. Further, in-depth structural analysis of purified lignins from the ospmt1 ospmt2-2 mutant compared with control lignins from wild-type rice revealed stark changes in polymer structures, including alterations in syringyl/guaiacyl aromatic unit ratios and inter-monomeric linkage patterns, and increased molecular weights. Our results provide insights into lignin polymerization in grasses that will be useful for the optimization of bioengineering approaches for the effective use of biomass in biorefineries.
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Affiliation(s)
- Lydia Pui Ying Lam
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan
- Center for Crossover Education, Graduate School of Engineering Science, Akita University, Akita, Akita 010-0852, Japan
| | - Yuki Tobimatsu
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Shiro Suzuki
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan
- Faculty of Applied Biological Sciences, Graduate School of Natural Science and Technology, and The United Graduate School of Agricultural Science, Gifu University, Gifu, Gifu 501-1193Japan
| | - Takuto Tanaka
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Senri Yamamoto
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Yuri Takeda-Kimura
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Yuriko Osakabe
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8502Japan
| | - Keishi Osakabe
- Faculty of Bioscience and Bioindustry, Tokushima University,Tokushima, Tokushima 770-8503Japan
| | - John Ralph
- Department of Biochemistry, and the U.S. Department of Energy Great Lakes Bioenergy Research Center, Wisconsin Energy Institute, University of Wisconsin, Madison, WI 53726, USA
| | - Laura E Bartley
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan
- Institute of Biological Chemistry, Washington State University, Pullman, WA 99164, USA
| | - Toshiaki Umezawa
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Kyoto 611-0011, Japan
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Houston K, Learmonth A, Hassan AS, Lahnstein J, Looseley M, Little A, Waugh R, Burton RA, Halpin C. Natural variation in HvAT10 underlies grain cell wall-esterified phenolic acid content in cultivated barley. FRONTIERS IN PLANT SCIENCE 2023; 14:1095862. [PMID: 37235033 PMCID: PMC10206312 DOI: 10.3389/fpls.2023.1095862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 04/06/2023] [Indexed: 05/28/2023]
Abstract
The phenolic acids, ferulic acid and p-coumaric acid, are components of plant cell walls in grasses, including many of our major food crops. They have important health-promoting properties in grain, and influence the digestibility of biomass for industrial processing and livestock feed. Both phenolic acids are assumed to be critical to cell wall integrity and ferulic acid, at least, is important for cross-linking cell wall components, but the role of p-coumaric acid is unclear. Here we identify alleles of a BAHD p-coumaroyl arabinoxylan transferase, HvAT10, as responsible for the natural variation in cell wall-esterified phenolic acids in whole grain within a cultivated two-row spring barley panel. We show that HvAT10 is rendered non-functional by a premature stop codon mutation in half of the genotypes in our mapping panel. This results in a dramatic reduction in grain cell wall-esterifed p-coumaric acid, a moderate rise in ferulic acid, and a clear increase in the ferulic acid to p-coumaric acid ratio. The mutation is virtually absent in wild and landrace germplasm suggesting an important function for grain arabinoxylan p-coumaroylation pre-domestication that is dispensable in modern agriculture. Intriguingly, we detected detrimental impacts of the mutated locus on grain quality traits where it was associated with smaller grain and poorer malting properties. HvAT10 could be a focus for improving grain quality for malting or phenolic acid content in wholegrain foods.
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Affiliation(s)
- Kelly Houston
- Cell and Molecular Sciences, The James Hutton Institute, Scotland, United Kingdom
| | - Amy Learmonth
- Division of Plant Sciences, School of Life Sciences, University of Dundee at The James Hutton Institute, Scotland, United Kingdom
| | - Ali Saleh Hassan
- School of Agriculture, Food and Wine, University of Adelaide, Urrbrae, SA, Australia
| | - Jelle Lahnstein
- School of Agriculture, Food and Wine, University of Adelaide, Urrbrae, SA, Australia
| | - Mark Looseley
- Cell and Molecular Sciences, The James Hutton Institute, Scotland, United Kingdom
| | - Alan Little
- School of Agriculture, Food and Wine, University of Adelaide, Urrbrae, SA, Australia
| | - Robbie Waugh
- Cell and Molecular Sciences, The James Hutton Institute, Scotland, United Kingdom
- Division of Plant Sciences, School of Life Sciences, University of Dundee at The James Hutton Institute, Scotland, United Kingdom
- School of Agriculture, Food and Wine, University of Adelaide, Urrbrae, SA, Australia
| | - Rachel A. Burton
- School of Agriculture, Food and Wine, University of Adelaide, Urrbrae, SA, Australia
| | - Claire Halpin
- Division of Plant Sciences, School of Life Sciences, University of Dundee at The James Hutton Institute, Scotland, United Kingdom
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7
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Piro MC, Muylle H, Haesaert G. Exploiting Rye in Wheat Quality Breeding: The Case of Arabinoxylan Content. PLANTS (BASEL, SWITZERLAND) 2023; 12:737. [PMID: 36840085 PMCID: PMC9965444 DOI: 10.3390/plants12040737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 02/02/2023] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
Rye (Secale cereale subsp. cereale L.) has long been exploited as a valuable alternative genetic resource in wheat (Triticum aestivum L.) breeding. Indeed, the introgression of rye genetic material led to significant breakthroughs in the improvement of disease and pest resistance of wheat, as well as a few agronomic traits. While such traits remain a high priority in cereal breeding, nutritional aspects of grain crops are coming under the spotlight as consumers become more conscious about their dietary choices and the food industry strives to offer food options that meet their demands. To address this new challenge, wheat breeding can once again turn to rye to look for additional genetic variation. A nutritional aspect that can potentially greatly benefit from the introgression of rye genetic material is the dietary fibre content of flour. In fact, rye is richer in dietary fibre than wheat, especially in terms of arabinoxylan content. Arabinoxylan is a major dietary fibre component in wheat and rye endosperm flours, and it is associated with a variety of health benefits, including normalisation of glycaemic levels and promotion of the gut microbiota. Thus, it is a valuable addition to the human diet, and it can represent a novel target for wheat-rye introgression breeding.
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Affiliation(s)
- Maria Chiara Piro
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Valentin Vaerwyckweg 1, 9000 Ghent, Belgium
- Plant Sciences Unit, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Caritasstraat 39, 9090 Melle, Belgium
| | - Hilde Muylle
- Plant Sciences Unit, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Caritasstraat 39, 9090 Melle, Belgium
| | - Geert Haesaert
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Valentin Vaerwyckweg 1, 9000 Ghent, Belgium
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Chandrakanth NN, Zhang C, Freeman J, de Souza WR, Bartley LE, Mitchell RA. Modification of plant cell walls with hydroxycinnamic acids by BAHD acyltransferases. FRONTIERS IN PLANT SCIENCE 2023; 13:1088879. [PMID: 36733587 PMCID: PMC9887202 DOI: 10.3389/fpls.2022.1088879] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 12/28/2022] [Indexed: 06/18/2023]
Abstract
In the last decade it has become clear that enzymes in the "BAHD" family of acyl-CoA transferases play important roles in the addition of phenolic acids to form ester-linked moieties on cell wall polymers. We focus here on the addition of two such phenolics-the hydroxycinnamates, ferulate and p-coumarate-to two cell wall polymers, glucuronoarabinoxylan and to lignin. The resulting ester-linked feruloyl and p-coumaroyl moities are key features of the cell walls of grasses and other commelinid monocots. The capacity of ferulate to participate in radical oxidative coupling means that its addition to glucuronoarabinoxylan or to lignin has profound implications for the properties of the cell wall - allowing respectively oxidative crosslinking to glucuronoarabinoxylan chains or introducing ester bonds into lignin polymers. A subclade of ~10 BAHD genes in grasses is now known to (1) contain genes strongly implicated in addition of p-coumarate or ferulate to glucuronoarabinoxylan (2) encode enzymes that add p-coumarate or ferulate to lignin precursors. Here, we review the evidence for functions of these genes and the biotechnological applications of manipulating them, discuss our understanding of mechanisms involved, and highlight outstanding questions for future research.
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Affiliation(s)
| | - Chengcheng Zhang
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, United States
| | - Jackie Freeman
- Plant Sciences, Rothamsted Research, West Common, Harpenden, Hertfordshire, United Kingdom
| | | | - Laura E. Bartley
- Institute of Biological Chemistry, Washington State University, Pullman, WA, United States
| | - Rowan A.C. Mitchell
- Plant Sciences, Rothamsted Research, West Common, Harpenden, Hertfordshire, United Kingdom
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9
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Ye ZH, Zhong R. Outstanding questions on xylan biosynthesis. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2022; 325:111476. [PMID: 36174800 DOI: 10.1016/j.plantsci.2022.111476] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 08/25/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Xylan is the second most abundant polysaccharide in plant biomass. It is a crucial component of cell wall structure as well as a significant factor contributing to biomass recalcitrance. Xylan consists of a linear chain of β-1,4-linked xylosyl residues that are often substituted with glycosyl side chains, such as glucuronosyl/methylglucuronosyl and arabinofuranosyl residues, and acetylated at O-2 and/or O-3. Xylan from gymnosperms and dicots contains a unique reducing end tetrasaccharide sequence that is not detected in xylan from grasses, bryophytes and seedless vascular plants. Grass xylan is heavily decorated at O-3 with arabinofuranosyl residues that are frequently esterified with hydroxycinnamates. Genetic and biochemical studies have uncovered a number of genes involved in xylan backbone elongation and acetylation, xylan glycosyl substitutions and their modifications, and the synthesis of the unique xylan reducing end tetrasaccharide sequence, but some outstanding issues on the biosynthesis of xylan still remain unanswered. Here, we provide a brief overview of xylan structure and focus on discussion of the current understanding and open questions on xylan biosynthesis. Further elucidation of the biochemical mechanisms underlying xylan biosynthesis will not only shed new insights into cell wall biology but also provide molecular tools for genetic modification of biomass composition tailored for diverse end uses.
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Affiliation(s)
- Zheng-Hua Ye
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
| | - Ruiqin Zhong
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
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10
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Zhong R, Lee C, Cui D, Phillips DR, Adams ER, Jeong HY, Jung KH, Ye ZH. Identification of xylan arabinosyl 2-O-xylosyltransferases catalyzing the addition of 2-O-xylosyl residue onto arabinosyl side chains of xylan in grass species. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 112:193-206. [PMID: 35959609 DOI: 10.1111/tpj.15939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 07/13/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
Grass xylan, the major hemicellulose in both primary and secondary cell walls, is heavily decorated with α-1,3-linked arabinofuranosyl (Araf) residues that may be further substituted at O-2 with xylosyl (Xyl) or Araf residues. Although xylan 3-O-arabinosyltransferases (XATs) catalyzing 3-O-Araf addition onto xylan have been characterized, glycosyltransferases responsible for the transfer of 2-O-Xyl or 2-O-Araf onto 3-O-Araf residues of xylan to produce the Xyl-Araf and Araf-Araf disaccharide side chains remain to be identified. In this report, we showed that a rice GT61 member, named OsXAXT1 (xylan arabinosyl 2-O-xylosyltransferase 1) herein, was able to mediate the addition of Xyl-Araf disaccharide side chains onto xylan when heterologously co-expressed with OsXAT2 in the Arabidopsis gux1/2/3 (glucuronic acid substitution of xylan 1/2/3) triple mutant that lacks any glycosyl substitutions. Recombinant OsXAXT1 protein expressed in human embryonic kidney 293 cells exhibited a xylosyltransferase activity catalyzing the addition of Xyl from UDP-Xyl onto arabinosylated xylooligomers. Consistent with its function as a xylan arabinosyl 2-O-xylosyltransferase, CRISPR-Cas9-mediated mutations of the OsXAXT1 gene in transgenic rice plants resulted in a reduction in the level of Xyl-Araf disaccharide side chains in xylan. Furthermore, we revealed that XAXT1 close homologs from several other grass species, including switchgrass, maize, and Brachypodium, possessed the same functions as OsXAXT1, indicating functional conservation of XAXTs in grass species. Together, our findings establish that grass XAXTs are xylosyltransferases catalyzing Xyl transfer onto O-2 of Araf residues of xylan to form the Xyl-Araf disaccharide side chains, which furthers our understanding of genes involved in xylan biosynthesis.
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Affiliation(s)
- Ruiqin Zhong
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA
| | - Chanhui Lee
- Department of Plant & Environmental New Resources, College of Life Sciences, Kyung Hee University, Yongin, 17104, Republic of Korea
| | - Dongtao Cui
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Dennis R Phillips
- Department of Chemistry, University of Georgia, Athens, GA, 30602, USA
| | - Earle R Adams
- Department of Chemistry, University of Georgia, Athens, GA, 30602, USA
| | - Ho-Young Jeong
- Department of Plant & Environmental New Resources, College of Life Sciences, Kyung Hee University, Yongin, 17104, Republic of Korea
| | - Ki-Hong Jung
- Graduate School of Green-Bio Science, Kyung Hee University, Yongin, 17104, Republic of Korea
| | - Zheng-Hua Ye
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA
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11
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Möller SR, Lancefield CS, Oates NC, Simister R, Dowle A, Gomez LD, McQueen-Mason SJ. CRISPR/Cas9 suppression of OsAT10, a rice BAHD acyltransferase, reduces p-coumaric acid incorporation into arabinoxylan without increasing saccharification. FRONTIERS IN PLANT SCIENCE 2022; 13:926300. [PMID: 35937377 PMCID: PMC9355400 DOI: 10.3389/fpls.2022.926300] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 07/05/2022] [Indexed: 06/01/2023]
Abstract
Ester-linked hydroxycinnamic acids ferulic acid (FA) and para-coumaric acid (p-CA) play important roles in crosslinking within cell wall arabinoxylans (AX) and between AX and lignin in grass cell walls. The addition of hydroxycinnamates to AX, is mediated by the Mitchell clade of BAHD acyl-coenzyme A-utilizing transferases. Overexpression of OsAT10 (a Mitchell clade BAHD acyl transferase) in rice, has previously been shown to increase p-CA content in AX in leaves and stems, leading to increased cell wall digestibility, potentially associated with a concomitant decrease in FA content. To investigate the physiological role of OsAT10 we established CRISPR/Cas9 rice knock-out mutants devoid of OsAT10. Our analysis of hydroxycinnamic acid content in wild type plants revealed that AX associated p-CA is found almost exclusively in rice husks, with very little found in other tissues. Mutant plants were essentially devoid of ester-linked p-CA associated with AX, indicating that OsAT10 represents the major enzyme responsible for the addition of p-CA to arabinoxylan in rice plants. We found no change in the digestibility of rice husk lacking AX-associated p-CA, suggesting that the changes in digestibility seen in OsAT10 overexpressing plants were solely due to compensatory decreases in AX-associated FA.
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Affiliation(s)
| | - Christopher S. Lancefield
- School of Chemistry and Biomedical Science Research Complex, University of St. Andrews, St.Andrews, United Kingdom
| | - Nicola C. Oates
- CNAP, Biology Department, University of York, York, United Kingdom
| | - Rachael Simister
- CNAP, Biology Department, University of York, York, United Kingdom
| | - Adam Dowle
- Biology Department, Bioscience Technology Facility, University of York, York, United Kingdom
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12
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Mendes GGM, Mota TR, Bossoni GEB, Marchiosi R, Oliveira DMD, Constantin RP, Dos Santos WD, Ferrarese-Filho O. Inhibiting tricin biosynthesis improves maize lignocellulose saccharification. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2022; 178:12-19. [PMID: 35247693 DOI: 10.1016/j.plaphy.2022.02.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/14/2022] [Accepted: 02/19/2022] [Indexed: 06/14/2023]
Abstract
Lignin is a technological bottleneck to convert polysaccharides into fermentable sugars, and different strategies of genetic-based metabolic engineering have been applied to improve biomass saccharification. Using maize seedlings grown hydroponically for 24 h, we conducted a quick non-transgenic approach with five enzyme inhibitors of the lignin and tricin pathways. Two compounds [3,4-(methylenedioxy)cinnamic acid: MDCA and 2,4-pyridinedicarboxylic acid: PDCA] revealed interesting findings on root growth, lignin composition, and saccharification. By inhibiting hydroxycinnamoyl-CoA ligase, a key enzyme of phenylpropanoid pathway, MDCA decreased the lignin content and improved saccharification, but it decreased root growth. By inhibiting flavone synthase, a key enzyme of tricin biosynthesis, PDCA decreased total lignin content and improved saccharification without affecting root growth. PDCA was three-fold more effective than MDCA, suggesting that controlling lignin biosynthesis with enzymatic inhibitors may be an attractive strategy to improve biomass saccharification.
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Affiliation(s)
| | - Thatiane Rodrigues Mota
- Ghent University, Department of Plant Biotechnology and Bioinformatics and VIB Center for Plant Systems Biology, Ghent, Belgium
| | | | - Rogério Marchiosi
- Laboratory of Plant Biochemistry, State University of Maringá, Av. Colombo, 5790, 87020-900, Maringá, PR, Brazil
| | - Dyoni Matias de Oliveira
- Ghent University, Department of Plant Biotechnology and Bioinformatics and VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Rodrigo Polimeni Constantin
- Laboratory of Plant Biochemistry, State University of Maringá, Av. Colombo, 5790, 87020-900, Maringá, PR, Brazil
| | - Wanderley Dantas Dos Santos
- Laboratory of Plant Biochemistry, State University of Maringá, Av. Colombo, 5790, 87020-900, Maringá, PR, Brazil
| | - Osvaldo Ferrarese-Filho
- Laboratory of Plant Biochemistry, State University of Maringá, Av. Colombo, 5790, 87020-900, Maringá, PR, Brazil.
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13
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Fanelli A, Sullivan ML. Tools for protein structure prediction and for molecular docking applied to enzyme active site analysis: A case study using a BAHD hydroxycinnamoyltransferase. Methods Enzymol 2022; 683:41-79. [PMID: 37087195 DOI: 10.1016/bs.mie.2022.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Elucidating the structure of an enzyme and how substrates bind to the active site is an important step for understanding its reaction mechanism and function. Nevertheless, the methods available to obtain three-dimensional structures of proteins, such as x-ray crystallography and NMR, can be expensive and time-consuming. Considering this, an alternative is using structural bioinformatic tools to predict the tertiary structure of a protein from its primary sequence, followed by molecular docking of one or more substrates into the enzyme structure model. In the past few years, significant advances have been made in these computational tools, which can give useful information about the active site and enzyme-substrate interactions before the structure can be resolved using physical methods. Here, using common bean (Phaseolus vulgaris) hydroxycinnamoyl-coenzyme A:tetrahydroxyhexanedioic acid hydroxycinnamoyltransferase (HHHT) as an example, we describe methods and workflows for protein structure prediction and molecular docking that can be performed on a personal computer using only open-source tools.
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Affiliation(s)
- Amanda Fanelli
- US Dairy Forage Research Center, USDA Agricultural Research Service, Madison, WI, United States.
| | - Michael L Sullivan
- US Dairy Forage Research Center, USDA Agricultural Research Service, Madison, WI, United States
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14
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Zhong R, Cui D, Phillips DR, Sims NT, Ye ZH. Functional analysis of GT61 glycosyltransferases from grass species in xylan substitutions. PLANTA 2021; 254:131. [PMID: 34821996 DOI: 10.1007/s00425-021-03794-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 11/16/2021] [Indexed: 06/13/2023]
Abstract
Multiple rice GT61 members were demonstrated to be xylan arabinosyltransferases (XATs) mediating 3-O-arabinosylation of xylan and the functions of XATs and xylan 2-O-xylosyltransferases were shown to be conserved in grass species. Xylan is the major hemicellulose in the cell walls of grass species and it is typified by having arabinofuranosyl (Araf) substitutions. In this report, we demonstrated that four previously uncharacterized, Golgi-localized glycosyltransferases residing in clade A or B of the rice GT61 family were able to mediate 3-O-arabinosylation of xylan when heterologously expressed in the Arabidopsis gux1/2/3 triple mutant. Biochemical characterization of their recombinant proteins established that they were xylan arabinosyltransferases (XATs) capable of transferring Araf residues onto xylohexaose acceptors, and thus they were named OsXAT4, OsXAT5, OsXAT6 and OsXAT7. OsXAT5 and the previously identified OsXAT2 were shown to be able to arabinosylate xylooligomers with a degree of polymerization of as low as 3. Furthermore, a number of XAT homologs from maize, sorghum, Brachypodium and switchgrass were found to exhibit activities catalyzing Araf transfer onto xylohexaose, indicating that they are XATs involved in xylan arabinosylation in these grass species. Moreover, we revealed that homologs of another GT61 member, xylan 2-O-xylosyltransferase (XYXT1), from these grass species could mediate 2-O-xylosylation of xylan when expressed in the Arabidopsis gux1/2/3 mutant. Together, our findings indicate that multiple OsXATs are involved in 3-O-arabinosylation of xylan and the functions of XATs and XYXTs are conserved in grass species.
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Affiliation(s)
- Ruiqin Zhong
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA
| | - Dongtao Cui
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Dennis R Phillips
- Department of Chemistry, University of Georgia, Athens, GA, 30602, USA
| | - Nathanael T Sims
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA
| | - Zheng-Hua Ye
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA.
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15
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Tian Y, Lin CY, Park JH, Wu CY, Kakumanu R, Pidatala VR, Vuu KM, Rodriguez A, Shih PM, Baidoo EEK, Temple S, Simmons BA, Gladden JM, Scheller HV, Eudes A. Overexpression of the rice BAHD acyltransferase AT10 increases xylan-bound p-coumarate and reduces lignin in Sorghum bicolor. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:217. [PMID: 34801067 PMCID: PMC8606057 DOI: 10.1186/s13068-021-02068-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 11/06/2021] [Indexed: 05/14/2023]
Abstract
BACKGROUND The development of bioenergy crops with reduced recalcitrance to enzymatic degradation represents an important challenge to enable the sustainable production of advanced biofuels and bioproducts. Biomass recalcitrance is partly attributed to the complex structure of plant cell walls inside which cellulose microfibrils are protected by a network of hemicellulosic xylan chains that crosslink with each other or with lignin via ferulate (FA) bridges. Overexpression of the rice acyltransferase OsAT10 is an effective bioengineering strategy to lower the amount of FA involved in the formation of cell wall crosslinks and thereby reduce cell wall recalcitrance. The annual crop sorghum represents an attractive feedstock for bioenergy purposes considering its high biomass yields and low input requirements. Although we previously validated the OsAT10 engineering approach in the perennial bioenergy crop switchgrass, the effect of OsAT10 expression on biomass composition and digestibility in sorghum remains to be explored. RESULTS We obtained eight independent sorghum (Sorghum bicolor (L.) Moench) transgenic lines with a single copy of a construct designed for OsAT10 expression. Consistent with the proposed role of OsAT10 in acylating arabinosyl residues on xylan with p-coumarate (pCA), a higher amount of p-coumaroyl-arabinose was released from the cell walls of these lines upon hydrolysis with trifluoroacetic acid. However, no major changes were observed regarding the total amount of pCA or FA esters released from cell walls upon mild alkaline hydrolysis. Certain diferulate (diFA) isomers identified in alkaline hydrolysates were increased in some transgenic lines. The amount of the main cell wall monosaccharides glucose, xylose, and arabinose was unaffected. The transgenic lines showed reduced lignin content and their biomass released higher yields of sugars after ionic liquid pretreatment followed by enzymatic saccharification. CONCLUSIONS Expression of OsAT10 in sorghum leads to an increase of xylan-bound pCA without reducing the overall content of cell wall FA esters. Nevertheless, the amount of total cell wall pCA remains unchanged indicating that most pCA is ester-linked to lignin. Unlike other engineered plants overexpressing OsAT10 or a phylogenetically related acyltransferase with similar putative function, the improvements of biomass saccharification efficiency in sorghum OsAT10 lines are likely the result of lignin reductions rather than reductions of cell wall-bound FA. These results also suggest a relationship between xylan-bound pCA and lignification in cell walls.
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Affiliation(s)
- Yang Tian
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Chien-Yuan Lin
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | | | - Chuan-Yin Wu
- Forage Genetics International, West Salem, WI 54669 USA
| | - Ramu Kakumanu
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Venkataramana R. Pidatala
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Khanh M. Vuu
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Alberto Rodriguez
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Department of Biomaterials and Biomanufacturing, Sandia National Laboratories, Livermore, CA 94551 USA
| | - Patrick M. Shih
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
- Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720 USA
| | - Edward E. K. Baidoo
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | | | - Blake A. Simmons
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - John M. Gladden
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Department of Biomaterials and Biomanufacturing, Sandia National Laboratories, Livermore, CA 94551 USA
| | - Henrik V. Scheller
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
- Department of Plant and Microbial Biology, University of California-Berkeley, Berkeley, CA 94720 USA
| | - Aymerick Eudes
- Joint BioEnergy Institute, Emeryville, CA 94608 USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
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16
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Hanley SJ, Pellny TK, de Vega JJ, Castiblanco V, Arango J, Eastmond PJ, Heslop-Harrison JS(P, Mitchell RAC. Allele mining in diverse accessions of tropical grasses to improve forage quality and reduce environmental impact. ANNALS OF BOTANY 2021; 128:627-637. [PMID: 34320174 PMCID: PMC8422886 DOI: 10.1093/aob/mcab101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 07/27/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND AND AIMS The C4Urochloa species (syn. Brachiaria) and Megathyrsus maximus (syn. Panicum maximum) are used as pasture for cattle across vast areas in tropical agriculture systems in Africa and South America. A key target for variety improvement is forage quality: enhanced digestibility could decrease the amount of land required per unit production, and enhanced lipid content could decrease methane emissions from cattle. For these traits, loss-of-function (LOF) alleles in known gene targets are predicted to improve them, making a reverse genetics approach of allele mining feasible. We therefore set out to look for such alleles in diverse accessions of Urochloa species and Megathyrsus maximus from the genebank collection held at the CIAT. METHODS We studied allelic diversity of 20 target genes (11 for digestibility, nine for lipid content) in 104 accessions selected to represent genetic diversity and ploidy levels of U. brizantha, U. decumbens, U. humidicola, U. ruziziensis and M. maximum. We used RNA sequencing and then bait capture DNA sequencing to improve gene models in a U. ruziziensis reference genome to assign polymorphisms with high confidence. KEY RESULTS We found 953 non-synonymous polymorphisms across all genes and accessions; within these, we identified seven putative LOF alleles with high confidence, including those in the non-redundant SDP1 and BAHD01 genes present in diploid and tetraploid accessions. These LOF alleles could respectively confer increased lipid content and digestibility if incorporated into a breeding programme. CONCLUSIONS We demonstrated a novel, effective approach to allele discovery in diverse accessions using a draft reference genome from a single species. We used this to find gene variants in a collection of tropical grasses that could help reduce the environmental impact of cattle production.
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Affiliation(s)
| | | | | | | | - Jacobo Arango
- International Center for Tropical Agriculture (CIAT), Cali, Colombia
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17
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Fanelli A, Rancour DM, Sullivan M, Karlen SD, Ralph J, Riaño-Pachón DM, Vicentini R, Silva TDF, Ferraz A, Hatfield RD, Romanel E. Overexpression of a Sugarcane BAHD Acyltransferase Alters Hydroxycinnamate Content in Maize Cell Wall. FRONTIERS IN PLANT SCIENCE 2021; 12:626168. [PMID: 33995431 PMCID: PMC8117936 DOI: 10.3389/fpls.2021.626168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 03/12/2021] [Indexed: 05/11/2023]
Abstract
The purification of hydroxycinnamic acids [p-coumaric acid (pCA) and ferulic acid (FA)] from grass cell walls requires high-cost processes. Feedstocks with increased levels of one hydroxycinnamate in preference to the other are therefore highly desirable. We identified and conducted expression analysis for nine BAHD acyltransferase ScAts genes from sugarcane. The high conservation of AT10 proteins, together with their similar gene expression patterns, supported a similar role in distinct grasses. Overexpression of ScAT10 in maize resulted in up to 75% increase in total pCA content. Mild hydrolysis and derivatization followed by reductive cleavage (DFRC) analysis showed that pCA increase was restricted to the hemicellulosic portion of the cell wall. Furthermore, total FA content was reduced up to 88%, resulting in a 10-fold increase in the pCA/FA ratio. Thus, we functionally characterized a sugarcane gene involved in pCA content on hemicelluloses and generated a C4 plant that is promising for valorizing pCA production in biorefineries.
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Affiliation(s)
- Amanda Fanelli
- Laboratório de Genômica de Plantas e Bioenergia (PGEMBL), Departamento de Biotecnologia, Escola de Engenharia de Lorena, Universidade de São Paulo, Lorena, Brazil
| | | | - Michael Sullivan
- U.S. Dairy Forage Research Center, Agricultural Research Service, U.S. Department of Agriculture, Madison, WI, United States
| | - Steven D. Karlen
- Department of Biochemistry, and The Department of Energy’s Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin, Madison, WI, United States
| | - John Ralph
- Department of Biochemistry, and The Department of Energy’s Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin, Madison, WI, United States
| | - Diego Mauricio Riaño-Pachón
- Laboratório de Biologia Computacional, Evolutiva e de Sistemas, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, Brazil
| | - Renato Vicentini
- Departamento de Genética e Evolução, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, Brazil
| | - Tatiane da Franca Silva
- Laboratório de Genômica de Plantas e Bioenergia (PGEMBL), Departamento de Biotecnologia, Escola de Engenharia de Lorena, Universidade de São Paulo, Lorena, Brazil
| | - André Ferraz
- Laboratório de Ciências da Madeira, Departamento de Biotecnologia, Escola de Engenharia de Lorena, Universidade de São Paulo, Lorena, Brazil
| | - Ronald D. Hatfield
- U.S. Dairy Forage Research Center, Agricultural Research Service, U.S. Department of Agriculture, Madison, WI, United States
| | - Elisson Romanel
- Laboratório de Genômica de Plantas e Bioenergia (PGEMBL), Departamento de Biotecnologia, Escola de Engenharia de Lorena, Universidade de São Paulo, Lorena, Brazil
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18
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Variable and dose-dependent response of Saccharomyces and non-Saccharomyces yeasts toward lignocellulosic hydrolysate inhibitors. Braz J Microbiol 2021; 52:575-586. [PMID: 33825150 DOI: 10.1007/s42770-021-00489-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 03/29/2021] [Indexed: 10/21/2022] Open
Abstract
Lignocellulosic hydrolysates will also contain compounds that inhibit microbial metabolism, such as organic acids, furaldehydes, and phenolic compounds. Understanding the response of yeasts toward such inhibitors is important to the development of different bioprocesses. In this work, the growth capacity of 7 industrial Saccharomyces cerevisiae and 7 non-Saccharomyces yeasts was compared in the presence of 3 different concentrations of furaldehydes (furfural and 5-hydroxymetil-furfural), organic acids (acetic and formic acids), and phenolic compounds (vanillin, syringaldehyde, ferulic, and coumaric acids). Then, Candida tropicalis JA2, Meyerozyma caribbica JA9, Wickerhamomyces anomalus 740, S. cerevisiae JP1, B1.1, and G06 were selected for fermentation in presence of acetic acid, HMF, and vanillin because they proved to be most tolerant to the tested compounds, while Spathaspora sp. JA1 because its xylose consumption rate. The results obtained showed a dose-dependent response of the yeasts toward the eight different inhibitors. Among the compared yeasts, S. cerevisiae strains presented higher tolerance than non-Saccharomyces, 3 of them with the highest tolerance among all. Regarding the non-Saccharomyces yeasts, C. tropicalis JA2 and W. anomalus 740 appeared as the most tolerant, whereas Spathaspora strains appeared very sensitive to the different compounds.
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