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D’Esposito D, Di Donato A, Puleo S, Nava M, Diretto G, Di Monaco R, Frusciante L, Ercolano MR. The Impact of Growing Area on the Expression of Fruit Traits Related to Sensory Perception in Two Tomato Cultivars. Int J Mol Sci 2024; 25:9015. [PMID: 39201701 PMCID: PMC11354283 DOI: 10.3390/ijms25169015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2024] [Revised: 08/13/2024] [Accepted: 08/15/2024] [Indexed: 09/03/2024] Open
Abstract
Environmental conditions greatly influence the quality of tomato fruit by affecting the expression of genes, the abundance of metabolites, and the perception of sensorial attributes. In this study, a fruit transcriptome investigation, a sensory test, and a metabolomic analysis were performed to evaluate the impact of the environment on two popular tomato cultivars grown in two Italian regions. The transcriptional profile of each cultivar, cultivated in two different areas, highlighted differential expression in genes involved in pathways related to cell wall components such as pectin, lignin, and hemicellulose and sugars as well as in amino acids, phenylpropanoids, and pigment synthesis. The cultivation area mainly affects sensory attributes related to texture and flavor and the metabolic pattern of cell wall precursors, sugars, glutamate, aspartate, and carotenoids. In the two genotypes cultivated in the same environment, some attributes and fruit-related quality processes are similarly affected, while others are differently influenced based on the specific genetic makeup of the tomato. A combination of transcriptomic, sensory, and metabolomic data obtained from the two tomato genotypes revealed that the environment has a profound effect on specific sensory traits, providing information on factors that shape the specific characteristics and genetic targets for improving tomato fruit characteristics.
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Affiliation(s)
- Daniela D’Esposito
- Department of Agricultural Sciences, University of Naples Federico II, 80055 Portici, Italy; (D.D.); (A.D.D.); (S.P.); (R.D.M.); (L.F.)
| | - Antimo Di Donato
- Department of Agricultural Sciences, University of Naples Federico II, 80055 Portici, Italy; (D.D.); (A.D.D.); (S.P.); (R.D.M.); (L.F.)
| | - Sharon Puleo
- Department of Agricultural Sciences, University of Naples Federico II, 80055 Portici, Italy; (D.D.); (A.D.D.); (S.P.); (R.D.M.); (L.F.)
| | - Matteo Nava
- Italian National Agency for New Technologies, Energy and Sustainable Development (ENEA), Casaccia, 00123 Rome, Italy; (M.N.)
| | - Gianfranco Diretto
- Italian National Agency for New Technologies, Energy and Sustainable Development (ENEA), Casaccia, 00123 Rome, Italy; (M.N.)
| | - Rossella Di Monaco
- Department of Agricultural Sciences, University of Naples Federico II, 80055 Portici, Italy; (D.D.); (A.D.D.); (S.P.); (R.D.M.); (L.F.)
| | - Luigi Frusciante
- Department of Agricultural Sciences, University of Naples Federico II, 80055 Portici, Italy; (D.D.); (A.D.D.); (S.P.); (R.D.M.); (L.F.)
| | - Maria Raffaella Ercolano
- Department of Agricultural Sciences, University of Naples Federico II, 80055 Portici, Italy; (D.D.); (A.D.D.); (S.P.); (R.D.M.); (L.F.)
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2
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Crowe S, Liu Y, Zhao X, Scheller HV, Keasling JD. Advances in Engineering Nucleotide Sugar Metabolism for Natural Product Glycosylation in Saccharomyces cerevisiae. ACS Synth Biol 2024; 13:1589-1599. [PMID: 38820348 PMCID: PMC11197093 DOI: 10.1021/acssynbio.3c00737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 05/13/2024] [Accepted: 05/20/2024] [Indexed: 06/02/2024]
Abstract
Glycosylation is a ubiquitous modification present across all of biology, affecting many things such as physicochemical properties, cellular recognition, subcellular localization, and immunogenicity. Nucleotide sugars are important precursors needed to study glycosylation and produce glycosylated products. Saccharomyces cerevisiae is a potentially powerful platform for producing glycosylated biomolecules, but it lacks nucleotide sugar diversity. Nucleotide sugar metabolism is complex, and understanding how to engineer it will be necessary to both access and study heterologous glycosylations found across biology. This review overviews the potential challenges with engineering nucleotide sugar metabolism in yeast from the salvage pathways that convert free sugars to their associated UDP-sugars to de novo synthesis where nucleotide sugars are interconverted through a complex metabolic network with governing feedback mechanisms. Finally, recent examples of engineering complex glycosylation of small molecules in S. cerevisiae are explored and assessed.
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Affiliation(s)
- Samantha
A. Crowe
- Department
of Chemical & Biomolecular Engineering, University of California, Berkeley, California 94720, United States
- California
Institute of Quantitative Biosciences (QB3), University of California, Berkeley, California 94720, United States
- Joint
BioEnergy Institute, Emeryville, California 94608, United States
| | - Yuzhong Liu
- California
Institute of Quantitative Biosciences (QB3), University of California, Berkeley, California 94720, United States
- Joint
BioEnergy Institute, Emeryville, California 94608, United States
| | - Xixi Zhao
- California
Institute of Quantitative Biosciences (QB3), University of California, Berkeley, California 94720, United States
- Joint
BioEnergy Institute, Emeryville, California 94608, United States
| | - Henrik V. Scheller
- Joint
BioEnergy Institute, Emeryville, California 94608, United States
- Environmental
Genomics and Systems Biology Division, Lawrence
Berkeley National Laboratory, Berkeley, California 94720, United States
- Department
of Plant and Microbial Biology, University
of California, Berkeley, California 94720, United States
| | - Jay D. Keasling
- Department
of Chemical & Biomolecular Engineering, University of California, Berkeley, California 94720, United States
- California
Institute of Quantitative Biosciences (QB3), University of California, Berkeley, California 94720, United States
- Joint
BioEnergy Institute, Emeryville, California 94608, United States
- Department
of Bioengineering, University of California, Berkeley, California 94720, United States
- Division
of Biological Systems and Engineering, Lawrence
Berkeley National Laboratory, Berkeley, California 94720, United States
- Center
for Biosustainability, Technical University
of Denmark, 2800 Kongens Lyngby, Denmark
- Center
for Synthetic Biochemistry, Shenzhen Institute
of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
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3
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Song J, Xu R, Guo Q, Wu C, Li Y, Wang X, Wang J, Qiu LJ. An omics strategy increasingly improves the discovery of genetic loci and genes for seed-coat color formation in soybean. MOLECULAR BREEDING : NEW STRATEGIES IN PLANT IMPROVEMENT 2023; 43:71. [PMID: 37663546 PMCID: PMC10471558 DOI: 10.1007/s11032-023-01414-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 08/13/2023] [Indexed: 09/05/2023]
Abstract
The phenotypic color of seeds is a complex agronomic trait and has economic and biological significance. The genetic control and molecular regulation mechanisms have been extensively studied. Here, we used a multi-omics strategy to explore the color formation in soybean seeds at a big data scale. We identified 13 large quantitative trait loci (QTL) for color with bulk segregating analysis in recombinant inbreeding lines. GWAS analysis of colors and decomposed attributes in 763 germplasms revealed associated SNP sites perfectly falling in five major QTL, suggesting inherited regulation on color during natural selection. Further transcriptomics analysis before and after color accumulation revealed 182 differentially expression genes (DEGs) in the five QTL, including known genes CHS, MYB, and F3'H involved in pigment accumulation. More DEGs with consistently upregulation or downregulation were identified as shared regulatory genes for two or more color formations while some DEGs were only for a specific color formation. For example, five upregulated DEGs in QTL qSC-3 were in flavonoid biosynthesis responsible for black and brown seed. The DEG (Glyma.08G085400) was identified in the purple seed only, which encodes gibberellin 2-beta-dioxygenase in the metabolism of colorful terpenoids. The candidate genes are involved in flavonoid biosynthesis, transcription factor regulation, gibberellin and terpenoid metabolism, photosynthesis, ascorbate and aldarate metabolism, and lipid metabolism. Seven differentially expressed transcription factors were also speculated that may regulate color formation, including a known MYB. The finds expand QTL and gene candidates for color formation, which could guide to breed better cultivars with designed colors. Supplementary Information The online version contains supplementary material available at 10.1007/s11032-023-01414-z.
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Affiliation(s)
- Jian Song
- Yangtze University, Jingzhou, 434025 Hubei P.R. China
| | - Ruixin Xu
- Yangtze University, Jingzhou, 434025 Hubei P.R. China
| | - Qingyuan Guo
- Yangtze University, Jingzhou, 434025 Hubei P.R. China
| | - Caiyu Wu
- Yangtze University, Jingzhou, 434025 Hubei P.R. China
| | - Yinghui Li
- The National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI)/Key Laboratory of Crop Gene Resource and Germplasm Enhancement (MOA)/Key Laboratory of Soybean Biology (Beijing) (MOA), Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Xuewen Wang
- Department of Genetics, University of Georgia, Athens, GA 30602 USA
| | - Jun Wang
- Yangtze University, Jingzhou, 434025 Hubei P.R. China
| | - Li-Juan Qiu
- The National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI)/Key Laboratory of Crop Gene Resource and Germplasm Enhancement (MOA)/Key Laboratory of Soybean Biology (Beijing) (MOA), Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
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4
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Borg AJE, Esquivias O, Coines J, Rovira C, Nidetzky B. Enzymatische C4-Epimerisierung von UDP-Glucuronsäure: präzise gesteuerte Rotation eines transienten 4-Ketointermediats für eine invertierende Reaktion ohne Decarboxylierung. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 135:e202211937. [PMID: 38515538 PMCID: PMC10952283 DOI: 10.1002/ange.202211937] [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: 08/12/2022] [Indexed: 03/23/2024]
Abstract
AbstractUDP‐Glucuronsäure(UDP‐GlcA)‐4‐Epimerase repräsentiert eine wichtige Fragestellung in der Enzymkatalyse: die Balance zwischen konformativer Flexibilität und genauer Positionierung. Das Enzym koordiniert die C4‐Oxidation des Substrats durch NAD+ mit der Rotation eines leicht decarboxylierbaren β‐Ketosäure‐Intermediats im aktiven Zentrum zur Ermöglichung der stereoinvertierenden Reduktion der Ketogruppe durch NADH. Wir zeigen hier die nur schwer erfassbare Rotationskoordinate des 4‐Ketointermediats. Distorsion des Zuckerrings in eine Boot‐Konformation erzeugt torsionale Mobilität in der Bindungstasche des Enzyms. Die Endpunkte der Rotation zeigen den 4‐Ketozucker in einer unverformten 4C1‐Sesselkonformation. Die äquatorial positionierte Carboxylatgruppe ist ungünstig für die 4‐Ketozucker‐Decarboxylierung. Varianten der Epimerase zeigen Decarboxylierung, wenn sie die Bindung mit der Carboxylatgruppe im entgegengesetzten Rotationsisomer des Substrats entfernen. R185A/D‐Substitutionen wandeln die Epimerase in UDP‐Xylose‐Synthasen um, welche UDP‐GlcA in stereospezifischen, konfigurationserhaltenden Reaktionen decarboxylieren.
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Affiliation(s)
- Annika J. E. Borg
- Institut für Biotechnologie und BioprozesstechnikTechnische Universität GrazPetersgasse 12/18010GrazÖsterreich
| | - Oriol Esquivias
- Department of Inorganic and Organic Chemistry (Section of Organic Chemistry)Institute of Computational and Theoretical Chemistry (IQTCUB)Martí i Franquès 108028BarcelonaSpanien
| | - Joan Coines
- Department of Inorganic and Organic Chemistry (Section of Organic Chemistry)Institute of Computational and Theoretical Chemistry (IQTCUB)Martí i Franquès 108028BarcelonaSpanien
- Derzeitige Adresse: Nostrum BiodiscoveryAv. De Josep Tarradellas, 8–1008029BarcelonaSpanien
| | - Carme Rovira
- Department of Inorganic and Organic Chemistry (Section of Organic Chemistry)Institute of Computational and Theoretical Chemistry (IQTCUB)Martí i Franquès 108028BarcelonaSpanien
- Institució Catalana de Recerca i Estudis Avançats (ICREA)Passeig Lluís Companys, 2308010BarcelonaSpanien
| | - Bernd Nidetzky
- Institut für Biotechnologie und BioprozesstechnikTechnische Universität GrazPetersgasse 12/18010GrazÖsterreich
- Austrian Center of Industrial Biotechnology (acib)Krenngasse 378010GrazÖsterreich
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5
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Borg AJE, Esquivias O, Coines J, Rovira C, Nidetzky B. Enzymatic C4-Epimerization of UDP-Glucuronic Acid: Precisely Steered Rotation of a Transient 4-Keto Intermediate for an Inverted Reaction without Decarboxylation. Angew Chem Int Ed Engl 2023; 62:e202211937. [PMID: 36308301 PMCID: PMC10107529 DOI: 10.1002/anie.202211937] [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: 08/12/2022] [Revised: 10/03/2022] [Accepted: 10/26/2022] [Indexed: 11/06/2022]
Abstract
UDP-glucuronic acid (UDP-GlcA) 4-epimerase illustrates an important problem regarding enzyme catalysis: balancing conformational flexibility with precise positioning. The enzyme coordinates the C4-oxidation of the substrate by NAD+ and rotation of a decarboxylation-prone β-keto acid intermediate in the active site, enabling stereoinverting reduction of the keto group by NADH. We reveal the elusive rotational landscape of the 4-keto intermediate. Distortion of the sugar ring into boat conformations induces torsional mobility in the enzyme's binding pocket. The rotational endpoints show that the 4-keto sugar has an undistorted 4 C1 chair conformation. The equatorially placed carboxylate group disfavors decarboxylation of the 4-keto sugar. Epimerase variants lead to decarboxylation upon removal of the binding interactions with the carboxylate group in the opposite rotational isomer of the substrate. Substitutions R185A/D convert the epimerase into UDP-xylose synthases that decarboxylate UDP-GlcA in stereospecific, configuration-retaining reactions.
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Affiliation(s)
- Annika J E Borg
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 12/1, 8010, Graz, Austria
| | - Oriol Esquivias
- Department of Inorganic and Organic Chemistry (Section of Organic Chemistry), Institute of Computational and Theoretical Chemistry (IQTCUB), Martí i Franquès 1, 08028, Barcelona, Spain
| | - Joan Coines
- Department of Inorganic and Organic Chemistry (Section of Organic Chemistry), Institute of Computational and Theoretical Chemistry (IQTCUB), Martí i Franquès 1, 08028, Barcelona, Spain.,Present address: Nostrum Biodiscovery, Av. De Josep Tarradellas, 8-10, 08029, Barcelona, Spain
| | - Carme Rovira
- Department of Inorganic and Organic Chemistry (Section of Organic Chemistry), Institute of Computational and Theoretical Chemistry (IQTCUB), Martí i Franquès 1, 08028, Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys, 23, 08010, Barcelona, Spain
| | - Bernd Nidetzky
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 12/1, 8010, Graz, Austria.,Austrian Center of Industrial Biotechnology (acib), Krenngasse 37, 8010, Graz, Austria
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6
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Potential of engineering the myo-inositol oxidation pathway to increase stress resilience in plants. Mol Biol Rep 2022; 49:8025-8035. [PMID: 35294703 DOI: 10.1007/s11033-022-07333-0] [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: 10/28/2021] [Accepted: 03/02/2022] [Indexed: 10/18/2022]
Abstract
Myo-inositol is one of the most abundant form of inositol. The myo-inositol (MI) serves as substrate to diverse biosynthesis pathways and hence it is conserved across life forms. The biosynthesis of MI is well studied in animals. Beyond biosynthesis pathway, implications of MI pathway and enzymes hold potential implications in plant physiology and crop improvement. Myo-inositol oxygenase (MIOX) enzyme catabolize MI into D-glucuronic acid (D-GlcUA). The MIOX enzyme family is well studied across few plants. More recently, the MI associated pathway's crosstalk with other important biosynthesis and stress responsive pathways in plants has drawn attention. The overall outcome from different plant species studied so far are very suggestive that MI derivatives and associated pathways could open new directions to explore stress responsive novel metabolic networks. There are evidences for upregulation of MI metabolic pathway genes, specially MIOX under different stress condition. We also found MIOX genes getting differentially expressed according to developmental and stress signals in Arabidopsis and wheat. In this review we try to highlight the missing links and put forward a tailored view over myo-inositol oxidation pathway and MIOX proteins.
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7
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Wan J, He M, Hou Q, Zou L, Yang Y, Wei Y, Chen X. Cell wall associated immunity in plants. STRESS BIOLOGY 2021; 1:3. [PMID: 37676546 PMCID: PMC10429498 DOI: 10.1007/s44154-021-00003-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/13/2021] [Indexed: 09/08/2023]
Abstract
The plant cell wall is the first physical and defensive barrier against pathogens. The plant cell wall usually undergoes dynamic remodeling as an immune response to prevent infection by pathogens. In this review, we summarize advances on relationship between cell wall and immunity in plants. In particular, we outline current progresses regarding the regulation of the cell wall components, including cellulose, hemicellulose, pectin and lignin, on plant disease resistance. We also discuss the impacts of cell wall-derived cellodextrin, oligogalacturonic acid and xyloglucan/xylan oligosaccharides as potent elicitors or signal molecules to trigger plant immune response. We further propose future studies on dissecting the molecular regulation of cell wall on plant immunity, which have potentials in practical application of crop breeding aiming at improvement of plant disease resistance.
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Affiliation(s)
- Jiangxue Wan
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University at Wenjiang, Chengdu, 611130, Sichuan, China
| | - Min He
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University at Wenjiang, Chengdu, 611130, Sichuan, China
| | - Qingqing Hou
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University at Wenjiang, Chengdu, 611130, Sichuan, China
| | - Lijuan Zou
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University at Wenjiang, Chengdu, 611130, Sichuan, China
- Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University, Mianyang, 621000, Sichuan, China
| | - Yihua Yang
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University at Wenjiang, Chengdu, 611130, Sichuan, China
| | - Yan Wei
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University at Wenjiang, Chengdu, 611130, Sichuan, China
| | - Xuewei Chen
- State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University at Wenjiang, Chengdu, 611130, Sichuan, China.
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8
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Figueroa CM, Lunn JE, Iglesias AA. Nucleotide-sugar metabolism in plants: the legacy of Luis F. Leloir. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:4053-4067. [PMID: 33948638 DOI: 10.1093/jxb/erab109] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 04/09/2021] [Indexed: 06/12/2023]
Abstract
This review commemorates the 50th anniversary of the Nobel Prize in Chemistry awarded to Luis F. Leloir 'for his discovery of sugar-nucleotides and their role in the biosynthesis of carbohydrates'. He and his co-workers discovered that activated forms of simple sugars, such as UDP-glucose and UDP-galactose, are essential intermediates in the interconversion of sugars. They elucidated the biosynthetic pathways for sucrose and starch, which are the major end-products of photosynthesis, and for trehalose. Trehalose 6-phosphate, the intermediate of trehalose biosynthesis that they discovered, is now a molecule of great interest due to its function as a sugar signalling metabolite that regulates many aspects of plant metabolism and development. The work of the Leloir group also opened the doors to an understanding of the biosynthesis of cellulose and other structural cell wall polysaccharides (hemicelluloses and pectins), and ascorbic acid (vitamin C). Nucleotide-sugars also serve as sugar donors for a myriad of glycosyltransferases that conjugate sugars to other molecules, including lipids, phytohormones, secondary metabolites, and proteins, thereby modifying their biological activity. In this review, we highlight the diversity of nucleotide-sugars and their functions in plants, in recognition of Leloir's rich and enduring legacy to plant science.
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Affiliation(s)
- Carlos M Figueroa
- Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Colectora Ruta Nacional 168 km 0, 3000 Santa Fe,Argentina
| | - John E Lunn
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany
| | - Alberto A Iglesias
- Instituto de Agrobiotecnología del Litoral, UNL, CONICET, FBCB, Colectora Ruta Nacional 168 km 0, 3000 Santa Fe,Argentina
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9
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Rüscher D, Corral JM, Carluccio AV, Klemens PAW, Gisel A, Stavolone L, Neuhaus HE, Ludewig F, Sonnewald U, Zierer W. Auxin signaling and vascular cambium formation enable storage metabolism in cassava tuberous roots. JOURNAL OF EXPERIMENTAL BOTANY 2021; 72:3688-3703. [PMID: 33712830 PMCID: PMC8096603 DOI: 10.1093/jxb/erab106] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 03/04/2021] [Indexed: 05/10/2023]
Abstract
Cassava storage roots are among the most important root crops worldwide, and represent one of the most consumed staple foods in sub-Saharan Africa. The vegetatively propagated tropical shrub can form many starchy tuberous roots from its stem. These storage roots are formed through the activation of secondary root growth processes. However, the underlying genetic regulation of storage root development is largely unknown. Here we report distinct structural and transcriptional changes occurring during the early phases of storage root development. A pronounced increase in auxin-related transcripts and the transcriptional activation of secondary growth factors, as well as a decrease in gibberellin-related transcripts were observed during the early stages of secondary root growth. This was accompanied by increased cell wall biosynthesis, most notably increased during the initial xylem expansion within the root vasculature. Starch storage metabolism was activated only after the formation of the vascular cambium. The formation of non-lignified xylem parenchyma cells and the activation of starch storage metabolism coincided with increased expression of the KNOX/BEL genes KNAT1, PENNYWISE, and POUND-FOOLISH, indicating their importance for proper xylem parenchyma function.
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Affiliation(s)
- David Rüscher
- Friedrich-Alexander-University Erlangen-Nuremberg, Department of Biology, Division of Biochemistry, Staudtstrasse 5, Erlangen, Germany
| | - José María Corral
- Friedrich-Alexander-University Erlangen-Nuremberg, Department of Biology, Division of Biochemistry, Staudtstrasse 5, Erlangen, Germany
| | - Anna Vittoria Carluccio
- International Institute for Tropical Agriculture, Ibadan, Oyo State, Nigeria
- Institute for Sustainable Plant Protection, CNR, Bari, Italy
| | - Patrick A W Klemens
- Technical University Kaiserslautern, Department of Biology, Division of Plant Physiology, Erwin-Schrödinger-Str. 22, Kaiserslautern, Germany
| | - Andreas Gisel
- International Institute for Tropical Agriculture, Ibadan, Oyo State, Nigeria
- Institute for Biomedical Technologies, CNR, Bari, Italy
| | - Livia Stavolone
- International Institute for Tropical Agriculture, Ibadan, Oyo State, Nigeria
- Institute for Sustainable Plant Protection, CNR, Bari, Italy
| | - H Ekkehard Neuhaus
- Technical University Kaiserslautern, Department of Biology, Division of Plant Physiology, Erwin-Schrödinger-Str. 22, Kaiserslautern, Germany
| | - Frank Ludewig
- Friedrich-Alexander-University Erlangen-Nuremberg, Department of Biology, Division of Biochemistry, Staudtstrasse 5, Erlangen, Germany
- Present address: KWS Saat SE, Grimsehlstraße 31, D-37574 Einbeck, Germany
| | - Uwe Sonnewald
- Friedrich-Alexander-University Erlangen-Nuremberg, Department of Biology, Division of Biochemistry, Staudtstrasse 5, Erlangen, Germany
| | - Wolfgang Zierer
- Friedrich-Alexander-University Erlangen-Nuremberg, Department of Biology, Division of Biochemistry, Staudtstrasse 5, Erlangen, Germany
- Correspondence:
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10
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Rüscher D, Corral JM, Carluccio AV, Klemens PAW, Gisel A, Stavolone L, Neuhaus HE, Ludewig F, Sonnewald U, Zierer W. Auxin signaling and vascular cambium formation enable storage metabolism in cassava tuberous roots. JOURNAL OF EXPERIMENTAL BOTANY 2021. [PMID: 33712830 DOI: 10.5061/dryad.0cfxpnw0t] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Cassava storage roots are among the most important root crops worldwide, and represent one of the most consumed staple foods in sub-Saharan Africa. The vegetatively propagated tropical shrub can form many starchy tuberous roots from its stem. These storage roots are formed through the activation of secondary root growth processes. However, the underlying genetic regulation of storage root development is largely unknown. Here we report distinct structural and transcriptional changes occurring during the early phases of storage root development. A pronounced increase in auxin-related transcripts and the transcriptional activation of secondary growth factors, as well as a decrease in gibberellin-related transcripts were observed during the early stages of secondary root growth. This was accompanied by increased cell wall biosynthesis, most notably increased during the initial xylem expansion within the root vasculature. Starch storage metabolism was activated only after the formation of the vascular cambium. The formation of non-lignified xylem parenchyma cells and the activation of starch storage metabolism coincided with increased expression of the KNOX/BEL genes KNAT1, PENNYWISE, and POUND-FOOLISH, indicating their importance for proper xylem parenchyma function.
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Affiliation(s)
- David Rüscher
- Friedrich-Alexander-University Erlangen-Nuremberg, Department of Biology, Division of Biochemistry, Staudtstrasse 5, Erlangen, Germany
| | - José María Corral
- Friedrich-Alexander-University Erlangen-Nuremberg, Department of Biology, Division of Biochemistry, Staudtstrasse 5, Erlangen, Germany
| | - Anna Vittoria Carluccio
- International Institute for Tropical Agriculture, Ibadan, Oyo State, Nigeria
- Institute for Sustainable Plant Protection, CNR, Bari, Italy
| | - Patrick A W Klemens
- Technical University Kaiserslautern, Department of Biology, Division of Plant Physiology, Erwin-Schrödinger-Str. 22, Kaiserslautern, Germany
| | - Andreas Gisel
- International Institute for Tropical Agriculture, Ibadan, Oyo State, Nigeria
- Institute for Biomedical Technologies, CNR, Bari, Italy
| | - Livia Stavolone
- International Institute for Tropical Agriculture, Ibadan, Oyo State, Nigeria
- Institute for Sustainable Plant Protection, CNR, Bari, Italy
| | - H Ekkehard Neuhaus
- Technical University Kaiserslautern, Department of Biology, Division of Plant Physiology, Erwin-Schrödinger-Str. 22, Kaiserslautern, Germany
| | - Frank Ludewig
- Friedrich-Alexander-University Erlangen-Nuremberg, Department of Biology, Division of Biochemistry, Staudtstrasse 5, Erlangen, Germany
| | - Uwe Sonnewald
- Friedrich-Alexander-University Erlangen-Nuremberg, Department of Biology, Division of Biochemistry, Staudtstrasse 5, Erlangen, Germany
| | - Wolfgang Zierer
- Friedrich-Alexander-University Erlangen-Nuremberg, Department of Biology, Division of Biochemistry, Staudtstrasse 5, Erlangen, Germany
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11
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Zhang W, Qin W, Li H, Wu AM. Biosynthesis and Transport of Nucleotide Sugars for Plant Hemicellulose. FRONTIERS IN PLANT SCIENCE 2021; 12:723128. [PMID: 34868108 PMCID: PMC8636097 DOI: 10.3389/fpls.2021.723128] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 10/22/2021] [Indexed: 05/13/2023]
Abstract
Hemicellulose is entangled with cellulose through hydrogen bonds and meanwhile acts as a bridge for the deposition of lignin monomer in the secondary wall. Therefore, hemicellulose plays a vital role in the utilization of cell wall biomass. Many advances in hemicellulose research have recently been made, and a large number of genes and their functions have been identified and verified. However, due to the diversity and complexity of hemicellulose, the biosynthesis and regulatory mechanisms are yet unknown. In this review, we summarized the types of plant hemicellulose, hemicellulose-specific nucleotide sugar substrates, key transporters, and biosynthesis pathways. This review will contribute to a better understanding of substrate-level regulation of hemicellulose synthesis.
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Affiliation(s)
- Wenjuan Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architectures, South China Agricultural University, Guangzhou, China
| | - Wenqi Qin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architectures, South China Agricultural University, Guangzhou, China
| | - Huiling Li
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architectures, South China Agricultural University, Guangzhou, China
| | - Ai-min Wu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
- Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architectures, South China Agricultural University, Guangzhou, China
- Guangdong Laboratory of Lingnan Modern Agriculture, Guangzhou, China
- *Correspondence: Ai-min Wu,
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12
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Borg AJE, Beerens K, Pfeiffer M, Desmet T, Nidetzky B. Stereo-electronic control of reaction selectivity in short-chain dehydrogenases: Decarboxylation, epimerization, and dehydration. Curr Opin Chem Biol 2020; 61:43-52. [PMID: 33166830 DOI: 10.1016/j.cbpa.2020.09.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 09/18/2020] [Accepted: 09/27/2020] [Indexed: 12/20/2022]
Abstract
Sugar nucleotide-modifying enzymes of the short-chain dehydrogenase/reductase type use transient oxidation-reduction by a tightly bound nicotinamide cofactor as a common strategy of catalysis to promote a diverse set of reactions, including decarboxylation, single- or double-site epimerization, and dehydration. Although the basic mechanistic principles have been worked out decades ago, the finely tuned control of reactivity and selectivity in several of these enzymes remains enigmatic. Recent evidence on uridine 5'-diphosphate (UDP)-glucuronic acid decarboxylases (UDP-xylose synthase, UDP-apiose/UDP-xylose synthase) and UDP-glucuronic acid-4-epimerase suggests that stereo-electronic constraints established at the enzyme's active site control the selectivity, and the timing of the catalytic reaction steps, in the conversion of the common substrate toward different products. The mechanistic idea of stereo-electronic control is extended to epimerases and dehydratases that deprotonate the Cα of the transient keto-hexose intermediate. The human guanosine 5'-diphosphate (GDP)-mannose 4,6-dehydratase was recently shown to use a minimal catalytic machinery, exactly as predicted earlier from theoretical considerations, for the β-elimination of water from the keto-hexose species.
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Affiliation(s)
- Annika J E Borg
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, 8010, Graz, Austria
| | - Koen Beerens
- Centre for Synthetic Biology, Department of Biotechnology, Ghent University, 9000, Ghent, Belgium
| | - Martin Pfeiffer
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, 8010, Graz, Austria; Austrian Centre of Industrial Biotechnology (acib), 8010, Graz, Austria
| | - Tom Desmet
- Centre for Synthetic Biology, Department of Biotechnology, Ghent University, 9000, Ghent, Belgium; Austrian Centre of Industrial Biotechnology (acib), 8010, Graz, Austria
| | - Bernd Nidetzky
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, 8010, Graz, Austria; Austrian Centre of Industrial Biotechnology (acib), 8010, Graz, Austria.
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13
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Yang A, Kong L, Wang H, Yao X, Xie F, Wang H, Ao X. Response of Soybean Root to Phosphorus Deficiency under Sucrose Feeding: Insight from Morphological and Metabolome Characterizations. BIOMED RESEARCH INTERNATIONAL 2020; 2020:2148032. [PMID: 32904516 PMCID: PMC7456465 DOI: 10.1155/2020/2148032] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/29/2020] [Accepted: 08/06/2020] [Indexed: 12/13/2022]
Abstract
Phosphorus (P) is one the least available essential plant macronutrients in soils that is a major constraint on plant growth. Soybean (Glycine max L.) production is often limited due to low P availability. The better management of P deficiency requires improvement of soybean's P use efficiency. Sugars are implicated in P starvation responses, and a complete understanding of the role of sucrose together with P in coordinating P starvation responses is missing in soybean. This study explored global metabolomic changes in previously screened low-P-tolerant (Liaodou, L13) and low-P-sensitive (Tiefeng 3, T3) soybean genotypes by liquid chromatography coupled mass spectrometry. We also studied the root morphological response to sucrose application (1%) in P-starved soybean genotypes against normal P supply. Root morphology in L13 genotype has significantly improved P starvation responses as compared to the T3 genotype. Exogenous sucrose application greatly affected root length, root volume, and root surface area in L13 genotype while low-P-sensitive genotype, i.e., T3, only responded by increasing number of lateral roots. Root : shoot ratio increased after sucrose treatment regardless of P conditions, in both genotypes. T3 showed a relatively higher number of differentially accumulated metabolites between P-starved and normal P conditions as compared to L13 genotype. Common metabolites accumulated under the influence of sucrose were 5-O-methylembelin, D-glucuronic acid, and N-acetyl-L-phenylalanine. We have discussed the possible roles of the pathways associated with these metabolites. The differentially accumulated metabolites between both genotypes under the influence of sucrose are also discussed. These results are important to further explore the role of sucrose in the observed pathways. Especially, our results are relevant to formulate strategies for improving P efficiency of soybean genotypes with different P efficiencies.
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Affiliation(s)
- Ahui Yang
- College of Agronomy, Shenyang Agricultural University, Shenyang 110866, China
| | - Lingjian Kong
- College of Agronomy, Shenyang Agricultural University, Shenyang 110866, China
| | - Hui Wang
- College of Agronomy, Shenyang Agricultural University, Shenyang 110866, China
| | - Xingdong Yao
- College of Agronomy, Shenyang Agricultural University, Shenyang 110866, China
| | - Futi Xie
- College of Agronomy, Shenyang Agricultural University, Shenyang 110866, China
| | - Haiying Wang
- College of Agronomy, Shenyang Agricultural University, Shenyang 110866, China
| | - Xue Ao
- College of Agronomy, Shenyang Agricultural University, Shenyang 110866, China
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14
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Borg AJE, Dennig A, Weber H, Nidetzky B. Mechanistic characterization of UDP-glucuronic acid 4-epimerase. FEBS J 2020; 288:1163-1178. [PMID: 32645249 PMCID: PMC7984243 DOI: 10.1111/febs.15478] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/22/2020] [Accepted: 07/06/2020] [Indexed: 12/27/2022]
Abstract
UDP-glucuronic acid (UDP-GlcA) is a central precursor in sugar nucleotide biosynthesis and common substrate for C4-epimerases and decarboxylases releasing UDP-galacturonic acid (UDP-GalA) and UDP-pentose products, respectively. Despite the different reactions catalyzed, the enzymes are believed to share mechanistic analogy rooted in their joint membership to the short-chain dehydrogenase/reductase (SDR) protein superfamily: Oxidation at the substrate C4 by enzyme-bound NAD+ initiates the catalytic pathway. Here, we present mechanistic characterization of the C4-epimerization of UDP-GlcA, which in comparison with the corresponding decarboxylation has been largely unexplored. The UDP-GlcA 4-epimerase from Bacillus cereus functions as a homodimer and contains one NAD+ /subunit (kcat = 0.25 ± 0.01 s-1 ). The epimerization of UDP-GlcA proceeds via hydride transfer from and to the substrate's C4 while retaining the enzyme-bound cofactor in its oxidized form (≥ 97%) at steady state and without trace of decarboxylation. The kcat for UDP-GlcA conversion shows a kinetic isotope effect of 2.0 (±0.1) derived from substrate deuteration at C4. The proposed enzymatic mechanism involves a transient UDP-4-keto-hexose-uronic acid intermediate whose formation is rate-limiting overall, and is governed by a conformational step before hydride abstraction from UDP-GlcA. Precise positioning of the substrate in a kinetically slow binding step may be important for the epimerase to establish stereo-electronic constraints in which decarboxylation of the labile β-keto acid species is prevented effectively. Mutagenesis and pH studies implicate the conserved Tyr149 as the catalytic base for substrate oxidation and show its involvement in the substrate positioning step. Collectively, this study suggests that based on overall mechanistic analogy, stereo-electronic control may be a distinguishing feature of catalysis by SDR-type epimerases and decarboxylases active on UDP-GlcA.
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Affiliation(s)
- Annika J E Borg
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Austria
| | - Alexander Dennig
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Austria.,Austrian Centre of Industrial Biotechnology, Graz, Austria
| | - Hansjörg Weber
- Institute of Organic Chemistry, Graz University of Technology, NAWI Graz, Austria
| | - Bernd Nidetzky
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Austria.,Austrian Centre of Industrial Biotechnology, Graz, Austria
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15
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Iacovino LG, Savino S, Borg AJE, Binda C, Nidetzky B, Mattevi A. Crystallographic snapshots of UDP-glucuronic acid 4-epimerase ligand binding, rotation, and reduction. J Biol Chem 2020; 295:12461-12473. [PMID: 32661196 DOI: 10.1074/jbc.ra120.014692] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/10/2020] [Indexed: 11/06/2022] Open
Abstract
UDP-glucuronic acid is converted to UDP-galacturonic acid en route to a variety of sugar-containing metabolites. This reaction is performed by a NAD+-dependent epimerase belonging to the short-chain dehydrogenase/reductase family. We present several high-resolution crystal structures of the UDP-glucuronic acid epimerase from Bacillus cereus The geometry of the substrate-NAD+ interactions is finely arranged to promote hydride transfer. The exquisite complementarity between glucuronic acid and its binding site is highlighted by the observation that the unligated cavity is occupied by a cluster of ordered waters whose positions overlap the polar groups of the sugar substrate. Co-crystallization experiments led to a structure where substrate- and product-bound enzymes coexist within the same crystal. This equilibrium structure reveals the basis for a "swing and flip" rotation of the pro-chiral 4-keto-hexose-uronic acid intermediate that results from glucuronic acid oxidation, placing the C4' atom in position for receiving a hydride ion on the opposite side of the sugar ring. The product-bound active site is almost identical to that of the substrate-bound structure and satisfies all hydrogen-bonding requirements of the ligand. The structure of the apoenzyme together with the kinetic isotope effect and mutagenesis experiments further outlines a few flexible loops that exist in discrete conformations, imparting structural malleability required for ligand rotation while avoiding leakage of the catalytic intermediate and/or side reactions. These data highlight the double nature of the enzymatic mechanism: the active site features a high degree of precision in substrate recognition combined with the flexibility required for intermediate rotation.
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Affiliation(s)
- Luca Giacinto Iacovino
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Simone Savino
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Graz, Austria
| | - Annika J E Borg
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Graz, Austria
| | - Claudia Binda
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Bernd Nidetzky
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Graz, Austria .,Austrian Centre of Industrial Biotechnology, Graz, Austria
| | - Andrea Mattevi
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
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16
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Ahmed RI, Ren A, Yang D, Ding A, Kong Y. Identification and characterization of pectin related gene NbGAE6 through virus-induced gene silencing in Nicotiana benthamiana. Gene 2020; 741:144522. [PMID: 32145329 DOI: 10.1016/j.gene.2020.144522] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 02/29/2020] [Accepted: 03/02/2020] [Indexed: 11/18/2022]
Abstract
Virus-induced gene silencing (VIGS) is a transient based reverse genetic tool used to elucidate the function of novel gene in N. benthamiana. In current study, 14 UDP-D-glucuronate 4-epimerase (GAE) family members were identified and their gene structure, phylogeny and expression pattern were analyzed. VIGS system was optimized for the functional characterization of NbGAE6 homologous genes in N. benthamiana. Whilst the GAE family is well-known for the interconversion of UDP-D-GlcA and UDP-D-GalA during pectin synthesis. Our results revealed that the downregulation of these genes significantly reduced the amount of GalA in the homogalacturunan which is the major component of pectin found in primary cell wall. Biphenyl assay and high performance liquid chromatography analysis (HPLC) depicted that the level of 'GalA' monosaccharide reduced to 40-51% in VIGS plants as compared to the wild type plants. Moreover, qRT-PCR also confirmed the downregulation of the NbGAE6 mRNA in VIGS plants. In all, this is the first comprehensive study of the optimization of VIGS system for the provision of rapid silencing of GAE family members in N. benthamiana, eliminating the need of stable transformants.
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Affiliation(s)
- Rana Imtiaz Ahmed
- Key Laboratory for Tobacco Gene Resources, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China
| | - Angyan Ren
- Key Laboratory for Tobacco Gene Resources, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China
| | - Dahai Yang
- Tobacco Breeding and Biotechnology Research Center, Yunnan Academy of Tobacco Agricultural Sciences, Key Laboratory of Tobacco Biotechnological Breeding, National Tobacco Genetic Engineering Research Center, Kunming 650021, China
| | - Anming Ding
- Key Laboratory for Tobacco Gene Resources, Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, China
| | - Yingzhen Kong
- College of Agronomy, Qingdao Agricultural University, Qingdao 266108, China.
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17
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Marček T, Hamow KÁ, Végh B, Janda T, Darko E. Metabolic response to drought in six winter wheat genotypes. PLoS One 2019; 14:e0212411. [PMID: 30779775 PMCID: PMC6380608 DOI: 10.1371/journal.pone.0212411] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 02/02/2019] [Indexed: 12/13/2022] Open
Abstract
Wheat is one of the most important cereals, whose growth and development is strongly limited by drought. This study investigated the physiological and metabolic response of six winter wheat cultivars to drought with the emphasis on the induction of dominant metabolites affected by the treatment and genotypes or both. The plants were exposed to a moderate (non-lethal) drought stress, which was induced by withholding watering for six days under controlled greenhouse conditions. A decline in CO2 assimilation (Pn) and transpiration rate, stomata closure, a decrease in relative water content (RWC) and increase of malondialdehyde content were observed in drought-treated plants of all cultivars. These changes were most pronounced in Ellvis, while Soissons was able to retain the higher RWC and Pn. Among the studied metabolites, sugars (sucrose, glucose, fructose, several disaccharides), organic acids (malic acid, oxalic acids), amino acids (proline, threonine, gamma-aminobutyric acid (GABA), glutamine) and sugar alcohols such as myo-inositol accumulated to higher levels in the plants exposed to drought stress in comparison with the control. The accumulation of several metabolites in response to drought differed between the genotypes. Drought induced the production of sucrose, malic acid and oxalic acid, unknown organic acid 1, unknown disaccharide 1, 2 and 3, GABA, L-threonine, glutamic acid in four (Soissons, Žitarka, Antonija or Toborzó) out of six genotypes. In addition, Soissons, which was the most drought tolerant genotype, accumulated the highest amount of unknown disaccharide 5, galactonic and phosphoric acids. The two most drought sensitive cultivars, Srpanjka and Ellvis, demonstrated different metabolic adjustment in response to the stress treatment. Srpanjka responded to drought by increasing the amount of glucose and fructose originated from hydrolyses of sucrose and accumulating unidentified sugar alcohols 1 and 2. In Ellvis, drought caused inhibition of photosynthetic carbon metabolism, as evidence by the decreased Pn, gs, RWC and accumulation levels of sugar metabolites (sucrose, glucose and fructose). The results revealed the differences in metabolic response to drought among the genotypes, which drew attention on metabolites related with general response and on those metabolites which are part of specific response that may play an important role in drought tolerance.
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Affiliation(s)
- Tihana Marček
- Department of Food and Nutrition Research, Faculty of Food Technology, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia
| | - Kamirán Áron Hamow
- Department of Zoology, Plant Protection Institute, Centre for Agricultural Research of the Hungarian Academy of Sciences, Budapest, Hungary
- Department of Plant Physiology, Agricultural Institute, Centre for Agricultural Research of the Hungarian Academy of Sciences, Martonvásár, Hungary
| | - Balázs Végh
- Department of Plant Physiology, Agricultural Institute, Centre for Agricultural Research of the Hungarian Academy of Sciences, Martonvásár, Hungary
| | - Tibor Janda
- Department of Plant Physiology, Agricultural Institute, Centre for Agricultural Research of the Hungarian Academy of Sciences, Martonvásár, Hungary
| | - Eva Darko
- Department of Plant Physiology, Agricultural Institute, Centre for Agricultural Research of the Hungarian Academy of Sciences, Martonvásár, Hungary
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18
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Mahboubi A, Niittylä T. Sucrose transport and carbon fluxes during wood formation. PHYSIOLOGIA PLANTARUM 2018; 164:67-81. [PMID: 29572842 DOI: 10.1111/ppl.12729] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/05/2018] [Accepted: 03/15/2018] [Indexed: 06/08/2023]
Abstract
Wood biosynthesis defines the chemical and structural properties of wood. The metabolic pathways that produce the precursors of wood cell wall polymers have a central role in defining wood properties. To make rational design of wood properties feasible, we need not only to understand the cell wall biosynthetic machinery, but also how sucrose transport and metabolism in developing wood connect to cell wall biosynthesis and how they respond to genetic and environmental cues. Here, we review the current understanding of the sucrose transport and primary metabolism pathways leading to the precursors of cell wall biosynthesis in woody plant tissues. We present both old, persistent questions and new emerging themes with a focus on wood formation in trees and draw upon evidence from the xylem tissues of herbaceous plants when it is relevant.
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Affiliation(s)
- Amir Mahboubi
- Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, Umeå, Sweden
| | - Totte Niittylä
- Umeå Plant Science Centre, Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
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19
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Ding X, Li J, Pan Y, Zhang Y, Ni L, Wang Y, Zhang X. Genome-Wide Identification and Expression Analysis of the UGlcAE Gene Family in Tomato. Int J Mol Sci 2018; 19:ijms19061583. [PMID: 29861481 PMCID: PMC6032376 DOI: 10.3390/ijms19061583] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/20/2018] [Accepted: 05/23/2018] [Indexed: 12/19/2022] Open
Abstract
The UGlcAE has the capability of interconverting UDP-d-galacturonic acid and UDP-d-glucuronic acid, and UDP-d-galacturonic acid is an activated precursor for the synthesis of pectins in plants. In this study, we identified nine UGlcAE protein-encoding genes in tomato. The nine UGlcAE genes that were distributed on eight chromosomes in tomato, and the corresponding proteins contained one or two trans-membrane domains. The phylogenetic analysis showed that SlUGlcAE genes could be divided into seven groups, designated UGlcAE1 to UGlcAE6, of which the UGlcAE2 were classified into two groups. Expression profile analysis revealed that the SlUGlcAE genes display diverse expression patterns in various tomato tissues. Selective pressure analysis indicated that all of the amino acid sites of SlUGlcAE proteins are undergoing purifying selection. Fifteen stress-, hormone-, and development-related elements were identified in the upstream regions (0.5 kb) of these SlUGlcAE genes. Furthermore, we investigated the expression patterns of SlUGlcAE genes in response to three hormones (indole-3-acetic acid (IAA), gibberellin (GA), and salicylic acid (SA)). We detected firmness, pectin contents, and expression levels of UGlcAE family genes during the development of tomato fruit. Here, we systematically summarize the general characteristics of the SlUGlcAE genes in tomato, which could provide a basis for further function studies of tomato UGlcAE genes.
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Affiliation(s)
- Xing Ding
- Key Laboratory of Horticulture Science for Southern Mountainous Regions (Chinese Ministry of Education), College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China.
| | - Jinhua Li
- Key Laboratory of Horticulture Science for Southern Mountainous Regions (Chinese Ministry of Education), College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China.
| | - Yu Pan
- Key Laboratory of Horticulture Science for Southern Mountainous Regions (Chinese Ministry of Education), College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China.
| | - Yue Zhang
- Key Laboratory of Horticulture Science for Southern Mountainous Regions (Chinese Ministry of Education), College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China.
| | - Lei Ni
- Key Laboratory of Horticulture Science for Southern Mountainous Regions (Chinese Ministry of Education), College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China.
| | - Yaling Wang
- Key Laboratory of Horticulture Science for Southern Mountainous Regions (Chinese Ministry of Education), College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China.
| | - Xingguo Zhang
- Key Laboratory of Horticulture Science for Southern Mountainous Regions (Chinese Ministry of Education), College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400715, China.
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20
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Verbančič J, Lunn JE, Stitt M, Persson S. Carbon Supply and the Regulation of Cell Wall Synthesis. MOLECULAR PLANT 2018; 11:75-94. [PMID: 29054565 DOI: 10.1016/j.molp.2017.10.004] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Revised: 10/04/2017] [Accepted: 10/05/2017] [Indexed: 05/23/2023]
Abstract
All plant cells are surrounded by a cell wall that determines the directionality of cell growth and protects the cell against its environment. Plant cell walls are comprised primarily of polysaccharides and represent the largest sink for photosynthetically fixed carbon, both for individual plants and in the terrestrial biosphere as a whole. Cell wall synthesis is a highly sophisticated process, involving multiple enzymes and metabolic intermediates, intracellular trafficking of proteins and cell wall precursors, assembly of cell wall polymers into the extracellular matrix, remodeling of polymers and their interactions, and recycling of cell wall sugars. In this review we discuss how newly fixed carbon, in the form of UDP-glucose and other nucleotide sugars, contributes to the synthesis of cell wall polysaccharides, and how cell wall synthesis is influenced by the carbon status of the plant, with a focus on the model species Arabidopsis (Arabidopsis thaliana).
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Affiliation(s)
- Jana Verbančič
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany; School of Biosciences, University of Melbourne, Parkville, VIC 3010, Australia
| | - John Edward Lunn
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany.
| | - Mark Stitt
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Staffan Persson
- School of Biosciences, University of Melbourne, Parkville, VIC 3010, Australia.
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21
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Saez-Aguayo S, Rautengarten C, Temple H, Sanhueza D, Ejsmentewicz T, Sandoval-Ibañez O, Doñas D, Parra-Rojas JP, Ebert B, Lehner A, Mollet JC, Dupree P, Scheller HV, Heazlewood JL, Reyes FC, Orellana A. UUAT1 Is a Golgi-Localized UDP-Uronic Acid Transporter That Modulates the Polysaccharide Composition of Arabidopsis Seed Mucilage. THE PLANT CELL 2017; 29:129-143. [PMID: 28062750 PMCID: PMC5304346 DOI: 10.1105/tpc.16.00465] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 11/14/2016] [Accepted: 12/31/2016] [Indexed: 05/17/2023]
Abstract
UDP-glucuronic acid (UDP-GlcA) is the precursor of many plant cell wall polysaccharides and is required for production of seed mucilage. Following synthesis in the cytosol, it is transported into the lumen of the Golgi apparatus, where it is converted to UDP-galacturonic acid (UDP-GalA), UDP-arabinose, and UDP-xylose. To identify the Golgi-localized UDP-GlcA transporter, we screened Arabidopsis thaliana mutants in genes coding for putative nucleotide sugar transporters for altered seed mucilage, a structure rich in the GalA-containing polysaccharide rhamnogalacturonan I. As a result, we identified UUAT1, which encodes a Golgi-localized protein that transports UDP-GlcA and UDP-GalA in vitro. The seed coat of uuat1 mutants had less GalA, rhamnose, and xylose in the soluble mucilage, and the distal cell walls had decreased arabinan content. Cell walls of other organs and cells had lower arabinose levels in roots and pollen tubes, but no differences were observed in GalA or xylose contents. Furthermore, the GlcA content of glucuronoxylan in the stem was not affected in the mutant. Interestingly, the degree of homogalacturonan methylation increased in uuat1 These results suggest that this UDP-GlcA transporter plays a key role defining the seed mucilage sugar composition and that its absence produces pleiotropic effects in this component of the plant extracellular matrix.
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Affiliation(s)
- Susana Saez-Aguayo
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Carsten Rautengarten
- ARC Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Victoria 3010, Australia
| | - Henry Temple
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Dayan Sanhueza
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Troy Ejsmentewicz
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Omar Sandoval-Ibañez
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Daniela Doñas
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Juan Pablo Parra-Rojas
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Berit Ebert
- ARC Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Victoria 3010, Australia
| | - Arnaud Lehner
- Normandy University, UniRouen, Laboratoire de Glycobiologie et Matrice Extracellulaire Végétale, EA4358, IRIB, VASI, France
| | - Jean-Claude Mollet
- Normandy University, UniRouen, Laboratoire de Glycobiologie et Matrice Extracellulaire Végétale, EA4358, IRIB, VASI, France
| | - Paul Dupree
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom
| | - Henrik V Scheller
- Joint BioEnergy Institute and Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94702
- Department of Plant and Microbial Biology, University of California, Berkeley, California 94720
| | - Joshua L Heazlewood
- ARC Centre of Excellence in Plant Cell Walls, School of BioSciences, The University of Melbourne, Victoria 3010, Australia
- Joint BioEnergy Institute and Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94702
| | - Francisca C Reyes
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
| | - Ariel Orellana
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Santiago, Chile
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22
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cDNA Isolation and Functional Characterization of UDP-d-glucuronic Acid 4-Epimerase Family from Ornithogalum caudatum. Molecules 2016; 21:molecules21111505. [PMID: 27834878 PMCID: PMC6273887 DOI: 10.3390/molecules21111505] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 11/01/2016] [Accepted: 11/06/2016] [Indexed: 11/16/2022] Open
Abstract
d-Galacturonic acid (GalA) is an important component of GalA-containing polysaccharides in Ornithogalum caudatum. The incorporation of GalA into these polysaccharides from UDP-d-galacturonic acid (UDP-GalA) was reasonably known. However, the cDNAs involved in the biosynthesis of UDP-GalA were still unknown. In the present investigation, one candidate UDP-d-glucuronic acid 4-epimerase (UGlcAE) family with three members was isolated from O. caudatum based on RNA-Seq data. Bioinformatics analyses indicated all of the three isoforms, designated as OcUGlcAE1~3, were members of short-chain dehydrogenases/reductases (SDRs) and shared two conserved motifs. The three full-length cDNAs were then transformed to Pichia pastoris GS115 for heterologous expression. Data revealed both the supernatant and microsomal fractions from the recombinant P. pastoris expressing OcUGlcAE3 can interconvert UDP-GalA and UDP-d-glucuronic acid (UDP-GlcA), while the other two OcUGlcAEs had no activity on UDP-GlcA and UDP-GalA. Furthermore, expression analyses of the three epimerases in varied tissues of O. caudatum were performed by real-time quantitative PCR (RT-qPCR). Results indicated OcUGlcAE3, together with the other two OcUGlcAE-like genes, was root-specific, displaying highest expression in roots. OcUGlcAE3 was UDP-d-glucuronic acid 4-epimerase and thus deemed to be involved in the biosynthesis of root polysaccharides. Moreover, OcUGlcAE3 was proposed to be environmentally induced.
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23
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Kotake T, Yamanashi Y, Imaizumi C, Tsumuraya Y. Metabolism of L-arabinose in plants. JOURNAL OF PLANT RESEARCH 2016; 129:781-792. [PMID: 27220955 PMCID: PMC5897480 DOI: 10.1007/s10265-016-0834-z] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 03/31/2016] [Indexed: 05/07/2023]
Abstract
L-Arabinose (L-Ara) is a plant-specific sugar accounting for 5-10 % of cell wall saccharides in Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa). L-Ara occurs in pectic arabinan, rhamnogalacturonan II, arabinoxylan, arabinogalactan-protein (AGP), and extensin in the cell walls, as well as in glycosylated signaling peptides like CLAVATA3 and small glycoconjugates such as quercetin 3-O-arabinoside. This review focuses on recent advances towards understanding the generation of L-Ara and the metabolism of L-Ara-containing molecules in plants.
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Affiliation(s)
- Toshihisa Kotake
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan.
| | - Yukiko Yamanashi
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Chiemi Imaizumi
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan
| | - Yoichi Tsumuraya
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama, 338-8570, Japan
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24
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Temple H, Saez-Aguayo S, Reyes FC, Orellana A. The inside and outside: topological issues in plant cell wall biosynthesis and the roles of nucleotide sugar transporters. Glycobiology 2016; 26:913-925. [PMID: 27507902 DOI: 10.1093/glycob/cww054] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 04/24/2016] [Indexed: 12/15/2022] Open
Abstract
The cell wall is a complex extracellular matrix composed primarily of polysaccharides. Noncellulosic polysaccharides, glycoproteins and proteoglycans are synthesized in the Golgi apparatus by glycosyltransferases (GTs), which use nucleotide sugars as donors to glycosylate nascent glycan and glycoprotein acceptors that are subsequently exported to the extracellular space. Many nucleotide sugars are synthesized in the cytosol, leading to a topological issue because the active sites of most GTs are located in the Golgi lumen. Nucleotide sugar transporters (NSTs) overcome this problem by translocating nucleoside diphosphate sugars from the cytosol into the lumen of the organelle. The structures of the cell wall components synthesized in the Golgi are diverse and complex; therefore, transporter activities are necessary so that the nucleotide sugars can provide substrates for the GTs. In this review, we describe the topology of reactions involved in polysaccharide biosynthesis in the Golgi and focus on the roles of NSTs as well as their impacts on cell wall structure when they are altered.
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Affiliation(s)
- Henry Temple
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Avenida República 217, Santiago, RM 837-0146, Chile
| | - Susana Saez-Aguayo
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Avenida República 217, Santiago, RM 837-0146, Chile
| | - Francisca C Reyes
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Avenida República 217, Santiago, RM 837-0146, Chile
| | - Ariel Orellana
- Centro de Biotecnología Vegetal, FONDAP Center for Genome Regulation, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Avenida República 217, Santiago, RM 837-0146, Chile
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25
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Bethke G, Thao A, Xiong G, Li B, Soltis NE, Hatsugai N, Hillmer RA, Katagiri F, Kliebenstein DJ, Pauly M, Glazebrook J. Pectin Biosynthesis Is Critical for Cell Wall Integrity and Immunity in Arabidopsis thaliana. THE PLANT CELL 2016; 28:537-56. [PMID: 26813622 PMCID: PMC4790862 DOI: 10.1105/tpc.15.00404] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 12/11/2015] [Accepted: 01/19/2016] [Indexed: 05/19/2023]
Abstract
Plant cell walls are important barriers against microbial pathogens. Cell walls of Arabidopsis thaliana leaves contain three major types of polysaccharides: cellulose, various hemicelluloses, and pectins. UDP-D-galacturonic acid, the key building block of pectins, is produced from the precursor UDP-D-glucuronic acid by the action of glucuronate 4-epimerases (GAEs). Pseudomonas syringae pv maculicola ES4326 (Pma ES4326) repressed expression of GAE1 and GAE6 in Arabidopsis, and immunity to Pma ES4326 was compromised in gae6 and gae1 gae6 mutant plants. These plants had brittle leaves and cell walls of leaves had less galacturonic acid. Resistance to specific Botrytis cinerea isolates was also compromised in gae1 gae6 double mutant plants. Although oligogalacturonide (OG)-induced immune signaling was unaltered in gae1 gae6 mutant plants, immune signaling induced by a commercial pectinase, macerozyme, was reduced. Macerozyme treatment or infection with B. cinerea released less soluble uronic acid, likely reflecting fewer OGs, from gae1 gae6 cell walls than from wild-type Col-0. Although both OGs and macerozyme-induced immunity to B. cinerea in Col-0, only OGs also induced immunity in gae1 gae6. Pectin is thus an important contributor to plant immunity, and this is due at least in part to the induction of immune responses by soluble pectin, likely OGs, that are released during plant-pathogen interactions.
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Affiliation(s)
- Gerit Bethke
- Department of Plant Biology, University of Minnesota, St. Paul, Minnesota 55108
| | - Amanda Thao
- Department of Plant Biology, University of Minnesota, St. Paul, Minnesota 55108
| | - Guangyan Xiong
- Energy Biosciences Institute, University of California, Berkeley, California 94720
| | - Baohua Li
- Department of Plant Sciences, University of California, Davis, California 95616
| | - Nicole E Soltis
- Department of Plant Sciences, University of California, Davis, California 95616
| | - Noriyuki Hatsugai
- Department of Plant Biology, University of Minnesota, St. Paul, Minnesota 55108
| | - Rachel A Hillmer
- Department of Plant Biology, University of Minnesota, St. Paul, Minnesota 55108 Plant Biological Sciences Graduate Program, University of Minnesota, St. Paul, Minnesota 55108
| | - Fumiaki Katagiri
- Department of Plant Biology, University of Minnesota, St. Paul, Minnesota 55108
| | | | - Markus Pauly
- Energy Biosciences Institute, University of California, Berkeley, California 94720 Department of Plant and Microbial Biology, University of California, Berkeley, California, 94720
| | - Jane Glazebrook
- Department of Plant Biology, University of Minnesota, St. Paul, Minnesota 55108
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26
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27
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Eixelsberger T, Weber H, Nidetzky B. Probing of the reaction pathway of human UDP-xylose synthase with site-directed mutagenesis. Carbohydr Res 2015; 416:1-6. [PMID: 26342152 DOI: 10.1016/j.carres.2015.08.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Revised: 08/11/2015] [Accepted: 08/12/2015] [Indexed: 11/28/2022]
Abstract
Uridine 5'-diphosphate (UDP)-xylose (UDP-Xyl) synthase (UXS) catalyzes the oxidative decarboxylation of UDP-glucuronic acid (UDP-GlcUA) to UDP-Xyl. The closely related UDP-glucuronic acid 4-epimerase (UGAE) interconverts UDP-GlcUA and UDP-galacturonic acid (UDP-GalUA) in a highly similar manner via the intermediate UDP-xylo-hexopyranos-4-uluronic acid (UDP-4-keto-GlcUA). Unlike UXS, however, UGAE prevents the decarboxylation. Human UXS (hUXS) and UGAE from Arabidopsis thaliana exhibit high structural similarity in the active site, but two catalytically important residues in hUXS (Glu(120) and Arg(277)) are replaced by Ser and Thr in the UGAE group. Additionally, Asn(176), which participates in substrate binding, is changed to Thr. We therefore analyzed single, double and triple mutants of hUXS carrying these substitutions to evaluate their significance for product specificity. All mutants showed considerably lower activities than wild-type hUXS (>1000-fold reduction). NMR spectroscopic analysis of the reaction products showed that UDP-β-L-threo-pentopyranos-4-ulose (UDP-4-keto-Xyl), UDP-Xyl or both, but no UDP-GalUA or UDP-4-keto-GlcUA were formed. Correlation of product characteristics, such as deuterium incorporation, with the amino acid replacements gave insights into structure-function relationships in UXS, suggesting that interaction between active site and overall enzyme structure rather than distinct conserved residues are decisive for product formation.
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Affiliation(s)
- Thomas Eixelsberger
- Institute of Biotechnology and Biochemical Engineering, NAWI Graz, Graz University of Technology, Petersgasse 12/I, A-8010 Graz, Austria
| | - Hansjörg Weber
- Institute of Organic Chemistry, NAWI Graz, Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria
| | - Bernd Nidetzky
- Institute of Biotechnology and Biochemical Engineering, NAWI Graz, Graz University of Technology, Petersgasse 12/I, A-8010 Graz, Austria; Austrian Centre of Industrial Biotechnology, Petersgasse 14, A-8010 Graz, Austria.
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28
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Kleczkowski LA, Decker D. Sugar Activation for Production of Nucleotide Sugars as Substrates for Glycosyltransferases in Plants. J Appl Glycosci (1999) 2015. [DOI: 10.5458/jag.jag.jag-2015_003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Affiliation(s)
| | - Daniel Decker
- Department of Plant Physiology, Umeå Plant Science Centre, Umeå University
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29
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McCarthy TW, Der JP, Honaas LA, dePamphilis CW, Anderson CT. Phylogenetic analysis of pectin-related gene families in Physcomitrella patens and nine other plant species yields evolutionary insights into cell walls. BMC PLANT BIOLOGY 2014; 14:79. [PMID: 24666997 PMCID: PMC4108027 DOI: 10.1186/1471-2229-14-79] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 02/26/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND Pectins are acidic sugar-containing polysaccharides that are universally conserved components of the primary cell walls of plants and modulate both tip and diffuse cell growth. However, many of their specific functions and the evolution of the genes responsible for producing and modifying them are incompletely understood. The moss Physcomitrella patens is emerging as a powerful model system for the study of plant cell walls. To identify deeply conserved pectin-related genes in Physcomitrella, we generated phylogenetic trees for 16 pectin-related gene families using sequences from ten plant genomes and analyzed the evolutionary relationships within these families. RESULTS Contrary to our initial hypothesis that a single ancestral gene was present for each pectin-related gene family in the common ancestor of land plants, five of the 16 gene families, including homogalacturonan galacturonosyltransferases, polygalacturonases, pectin methylesterases, homogalacturonan methyltransferases, and pectate lyase-like proteins, show evidence of multiple members in the early land plant that gave rise to the mosses and vascular plants. Seven of the gene families, the UDP-rhamnose synthases, UDP-glucuronic acid epimerases, homogalacturonan galacturonosyltransferase-like proteins, β-1,4-galactan β-1,4-galactosyltransferases, rhamnogalacturonan II xylosyltransferases, and pectin acetylesterases appear to have had a single member in the common ancestor of land plants. We detected no Physcomitrella members in the xylogalacturonan xylosyltransferase, rhamnogalacturonan I arabinosyltransferase, pectin methylesterase inhibitor, or polygalacturonase inhibitor protein families. CONCLUSIONS Several gene families related to the production and modification of pectins in plants appear to have multiple members that are conserved as far back as the common ancestor of mosses and vascular plants. The presence of multiple members of these families even before the divergence of other important cell wall-related genes, such as cellulose synthases, suggests a more complex role than previously suspected for pectins in the evolution of land plants. The presence of relatively small pectin-related gene families in Physcomitrella as compared to Arabidopsis makes it an attractive target for analysis of the functions of pectins in cell walls. In contrast, the absence of genes in Physcomitrella for some families suggests that certain pectin modifications, such as homogalacturonan xylosylation, arose later during land plant evolution.
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Affiliation(s)
- Thomas W McCarthy
- Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Joshua P Der
- Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Loren A Honaas
- Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Claude W dePamphilis
- Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Charles T Anderson
- Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
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30
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Geserick C, Tenhaken R. UDP-sugar pyrophosphorylase is essential for arabinose and xylose recycling, and is required during vegetative and reproductive growth in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013; 74:239-47. [PMID: 23373795 PMCID: PMC3659416 DOI: 10.1111/tpj.12116] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 01/04/2013] [Indexed: 05/20/2023]
Abstract
Numerous nucleotide sugars are needed in plants to synthesize cell wall polymers and glycoproteins. The de novo synthesis of nucleotide sugars is of major importance. During growth, however, some polymers are broken down to monosaccharides. Reactivation of these sugars into nucleotide sugars occurs in two steps: first, by a substrate-specific sugar-1-kinase and, second, by UDP-sugar-pyrophosphorylase (USP), which has broad substrate specificity. A knock-out of the USP gene results in non-fertile pollen. By using various genetic complementation approaches we obtained a strong (>95%) knock-down line in USP that allowed us to investigate the physiological role of the enzyme during the life cycle. Mutant plants show an arabinose reduction in the cell wall, and accumulate mainly two sugars, arabinose and xylose, in the cytoplasm. The arabinogalactanproteins in usp mutants show no significant reduction in size. USP is also part of the myo-inositol oxygenation pathway to UDP-glucuronic acid; however, free glucuronic acid does not accumulate in cells, suggesting alternative conversion pathways of this monosaccharide. The knock-down plants are mostly sterile because of the improper formation of anthers and pollen sacks.
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31
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Geserick C, Tenhaken R. UDP-sugar pyrophosphorylase is essential for arabinose and xylose recycling, and is required during vegetative and reproductive growth in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2013. [PMID: 23373795 DOI: 10.1111/tpj.2013.74.issue-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Numerous nucleotide sugars are needed in plants to synthesize cell wall polymers and glycoproteins. The de novo synthesis of nucleotide sugars is of major importance. During growth, however, some polymers are broken down to monosaccharides. Reactivation of these sugars into nucleotide sugars occurs in two steps: first, by a substrate-specific sugar-1-kinase and, second, by UDP-sugar-pyrophosphorylase (USP), which has broad substrate specificity. A knock-out of the USP gene results in non-fertile pollen. By using various genetic complementation approaches we obtained a strong (>95%) knock-down line in USP that allowed us to investigate the physiological role of the enzyme during the life cycle. Mutant plants show an arabinose reduction in the cell wall, and accumulate mainly two sugars, arabinose and xylose, in the cytoplasm. The arabinogalactanproteins in usp mutants show no significant reduction in size. USP is also part of the myo-inositol oxygenation pathway to UDP-glucuronic acid; however, free glucuronic acid does not accumulate in cells, suggesting alternative conversion pathways of this monosaccharide. The knock-down plants are mostly sterile because of the improper formation of anthers and pollen sacks.
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Affiliation(s)
- Claudia Geserick
- Department Cell Biology, Plant Physiology, University of Salzburg, Hellbrunnerstr. 34, Salzburg, 5020, Austria
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32
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Abstract
Recent progress in the identification and characterization of pectin biosynthetic proteins and the discovery of pectin domain-containing proteoglycans are changing our view of how pectin, the most complex family of plant cell wall polysaccharides, is synthesized. The functional confirmation of four types of pectin biosynthetic glycosyltransferases, the identification of multiple putative pectin glycosyl- and methyltransferases, and the characteristics of the GAUT1:GAUT7 homogalacturonan biosynthetic complex with its novel mechanism for retaining catalytic subunits in the Golgi apparatus and its 12 putative interacting proteins are beginning to provide a framework for the pectin biosynthetic process. We propose two partially overlapping hypothetical and testable models for pectin synthesis: the consecutive glycosyltransferase model and the domain synthesis model.
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Affiliation(s)
- Melani A Atmodjo
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602-4712, USA.
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33
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Bar-Peled M, Urbanowicz BR, O’Neill MA. The Synthesis and Origin of the Pectic Polysaccharide Rhamnogalacturonan II - Insights from Nucleotide Sugar Formation and Diversity. FRONTIERS IN PLANT SCIENCE 2012; 3:92. [PMID: 22639675 PMCID: PMC3355719 DOI: 10.3389/fpls.2012.00092] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Accepted: 04/23/2012] [Indexed: 05/02/2023]
Abstract
There is compelling evidence showing that the structurally complex pectic polysaccharide rhamnogalacturonan II (RG-II) exists in the primary cell wall as a borate cross-linked dimer and that this dimer is required for the assembly of a functional wall and for normal plant growth and development. The results of several studies have also established that RG-II structure and cross-linking is conserved in vascular plants and that RG-II likely appeared early in the evolution of land plants. Two features that distinguish RG-II from other plant polysaccharides are that RG-II is composed of 13 different glycoses linked to each other by up to 22 different glycosidic linkages and that RG-II is the only polysaccharide known to contain both apiose and aceric acid. Thus, one key event in land plant evolution was the emergence of genes encoding nucleotide sugar biosynthetic enzymes that generate the activated forms of apiose and aceric acid required for RG-II synthesis. Many of the genes involved in the generation of the nucleotide sugars used for RG-II synthesis have been functionally characterized. By contrast, only one glycosyltransferase involved in the assembly of RG-II has been identified. Here we provide an overview of the formation of the activated sugars required for RG-II synthesis and point to the possible cellular and metabolic processes that could be involved in assembling and controlling the formation of a borate cross-linked RG-II molecule. We discuss how nucleotide sugar synthesis is compartmentalized and how this may control the flux of precursors to facilitate and regulate the formation of RG-II.
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Affiliation(s)
- Maor Bar-Peled
- Department of Plant Biology, Complex Carbohydrate Research, The University of GeorgiaAthens, GA, USA
- *Correspondence: Maor Bar-Peled, Department of Plant Biology, Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA. e-mail:
| | | | - Malcolm A. O’Neill
- Complex Carbohydrate Research Center, The University of GeorgiaAthens, GA, USA
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Yang T, Bar-Peled Y, Smith JA, Glushka J, Bar-Peled M. In-microbe formation of nucleotide sugars in engineered Escherichia coli. Anal Biochem 2011; 421:691-8. [PMID: 22244806 DOI: 10.1016/j.ab.2011.12.028] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 12/09/2011] [Accepted: 12/14/2011] [Indexed: 11/24/2022]
Abstract
Numerous different nucleotide sugars are used as sugar donors for the biosynthesis of glycans by bacteria, humans, fungi, and plants. However, many of these nucleotide sugars are not available either in their native form or with the sugar portion labeled with a stable or radioactive isotope. Here we demonstrate the use of Escherichia coli metabolically engineered to contain genes that encode proteins that convert monosaccharides into their respective monosaccharide-1-phosphates and subsequently into the corresponding nucleotide sugars. In this system, which we designated "in-microbe", reactions occur within 2 to 4 h and can be used to generate nucleotide sugars in amounts ranging from 5 to 12.5 μg/ml cell culture. We show that the E. coli can be engineered to produce the seldom observed nucleotide sugars UDP-2-acetamido-2-deoxy-glucuronic acid (UDP-GlcNAcA) and UDP-2-acetamido-2-deoxy-xylose (UDP-XylNAc). Using similar strategies, we also engineered E. coli to synthesize UDP-galacturonic acid (UDP-GalA) and UDP-galactose (UDP-Gal). ¹³C- and ¹⁵N-labeled NDP-sugars are formed using [¹³C] glucose as the carbon source and with [¹⁵N]NH₄Cl as the nitrogen source.
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Affiliation(s)
- Ting Yang
- Complex Carbohydrate Research Center (CCRC), University of Georgia, Athens, GA 30602, USA
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35
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Evolution of plant nucleotide-sugar interconversion enzymes. PLoS One 2011; 6:e27995. [PMID: 22125650 PMCID: PMC3220709 DOI: 10.1371/journal.pone.0027995] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 10/29/2011] [Indexed: 11/19/2022] Open
Abstract
Nucleotide-diphospho-sugars (NDP-sugars) are the building blocks of diverse polysaccharides and glycoconjugates in all organisms. In plants, 11 families of NDP-sugar interconversion enzymes (NSEs) have been identified, each of which interconverts one NDP-sugar to another. While the functions of these enzyme families have been characterized in various plants, very little is known about their evolution and origin. Our phylogenetic analyses indicate that all the 11 plant NSE families are distantly related and most of them originated from different progenitor genes, which have already diverged in ancient prokaryotes. For instance, all NSE families are found in the lower land plant mosses and most of them are also found in aquatic algae, implicating that they have already evolved to be capable of synthesizing all the 11 different NDP-sugars. Particularly interesting is that the evolution of RHM (UDP-L-rhamnose synthase) manifests the fusion of genes of three enzymatic activities in early eukaryotes in a rather intriguing manner. The plant NRS/ER (nucleotide-rhamnose synthase/epimerase-reductase), on the other hand, evolved much later from the ancient plant RHMs through losing the N-terminal domain. Based on these findings, an evolutionary model is proposed to explain the origin and evolution of different NSE families. For instance, the UGlcAE (UDP-D-glucuronic acid 4-epimerase) family is suggested to have evolved from some chlamydial bacteria. Our data also show considerably higher sequence diversity among NSE-like genes in modern prokaryotes, consistent with the higher sugar diversity found in prokaryotes. All the NSE families are widely found in plants and algae containing carbohydrate-rich cell walls, while sporadically found in animals, fungi and other eukaryotes, which do not have or have cell walls with distinct compositions. Results of this study were shown to be highly useful for identifying unknown genes for further experimental characterization to determine their functions in the synthesis of diverse glycosylated molecules.
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Broach B, Gu X, Bar-Peled M. Biosynthesis of UDP-glucuronic acid and UDP-galacturonic acid in Bacillus cereus subsp. cytotoxis NVH 391-98. FEBS J 2011; 279:100-12. [PMID: 22023070 DOI: 10.1111/j.1742-4658.2011.08402.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The food borne pathogen Bacillus cereus produces uronic acid-containing glycans that are secreted in a shielding biofilm environment, and certain alkaliphilic Bacillus deposit uronate-glycan polymers in the cell wall when adapting to alkaline environments. The source of these acidic sugars is unknown and, in the present study, we describe the functional identification of an operon in Bacillus cerues subsp. cytotoxis NVH 391-98 that comprises genes involved in the synthesis of UDP-uronic acids in Bacillus spp. Within the operon, a UDP-glucose 6-dehydrogenase converts UDP-glucose in the presence of NAD(+) to UDP-glucuronic acid and NADH, and a UDP-GlcA 4-epimerase (UGlcAE) converts UDP-glucuronic acid to UDP-galacturonic acid. Interestingly, in vitro, both enzymes can utilize the TDP-sugar forms as well, albeit at lower catalytic efficiency. Unlike most of the very few bacterial 4-epimerases that have been characterized, which are promiscuous, the B. cereus UGlcAE enzyme is very specific and cannot use UDP-glucose, UDP-N-acetylglucosamine, UDP-N-acetylglucosaminuronic acid or UDP-xylose as substrates. Size exclusion chromatography suggests that UGlcAE is active as a monomer, unlike the dimeric form of plant enzymes; the Bacillus UDP-glucose 6-dehydrogenase is also found as a monomer. Phylogenic analysis further suggests that the Bacillus UGlcAE may have evolved separately from other bacterial and plant epimerases. Our results provide insight into the formation and function of uronic acid-containing glycans in the lifecycle of B. cereus and related species containing homologous operons, as well as a basis for determining the importance of these acidic glycans. We also discuss the ability to target UGlcAE as a drug candidate.
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Affiliation(s)
- Bryan Broach
- Complex Carbohydrate Research Center (CCRC), University of Georgia, Athens, GA 30602, USA
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Bar-Peled M, O'Neill MA. Plant nucleotide sugar formation, interconversion, and salvage by sugar recycling. ANNUAL REVIEW OF PLANT BIOLOGY 2011; 62:127-55. [PMID: 21370975 DOI: 10.1146/annurev-arplant-042110-103918] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Nucleotide sugars are the universal sugar donors for the formation of polysaccharides, glycoproteins, proteoglycans, glycolipids, and glycosylated secondary metabolites. At least 100 genes encode proteins involved in the formation of nucleotide sugars. These nucleotide sugars are formed using the carbohydrate derived from photosynthesis, the sugar generated by hydrolyzing translocated sucrose, the sugars released from storage carbohydrates, the salvage of sugars from glycoproteins and glycolipids, the recycling of sugars released during primary and secondary cell wall restructuring, and the sugar generated during plant-microbe interactions. Here we emphasize the importance of the salvage of sugars released from glycans for the formation of nucleotide sugars. We also outline how recent studies combining biochemical, genetic, molecular and cellular approaches have led to an increased appreciation of the role nucleotide sugars in all aspects of plant growth and development. Nevertheless, our understanding of these pathways at the single cell level is far from complete.
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Affiliation(s)
- Maor Bar-Peled
- Department of Plant Biology, University of Georgia, Athens, Georgia 30602, USA
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38
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Abstract
Biosynthesis of pectin and hemicelluloses occurs in the Golgi apparatus and is thought to involve spatial regulations and complex formation of biosynthetic enzymes and proteins. We have demonstrated that a combination of heterologous expression of recombinant proteins tagged with fluorescent proteins and live cell imaging with confocal laser scanning microscopy (CLSM) allows efficient visualization of biosynthetic enzymes and proteins in subcellular compartments. We have also successfully utilized bimolecular fluorescence complementation (BiFC) for in situ visualization of protein-protein interactions of pectin biosynthetic enzymes and for the determination of their membrane topology in the Golgi apparatus.
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Affiliation(s)
- Yumiko Sakuragi
- The Department of Plant Biology and Biotechnology, University of Copenhagen, Copenhagen, Denmark
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39
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Identification of a novel UDP-sugar pyrophosphorylase with a broad substrate specificity in Trypanosoma cruzi. Biochem J 2010; 429:533-43. [DOI: 10.1042/bj20100238] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The diverse types of glycoconjugates synthesized by trypanosomatid parasites are unique compared with the host cells. These glycans are required for the parasite survival, invasion or evasion of the host immune system. Synthesis of those glycoconjugates requires a constant supply of nucleotide-sugars (NDP-sugars), yet little is known about how these NDP-sugars are made and supplied. In the present paper, we report a functional gene from Trypanosoma cruzi that encodes a nucleotidyltransferase, which is capable of transforming different types of sugar 1-phosphates and NTP into NDP-sugars. In the forward reaction, the enzyme catalyses the formation of UDP-glucose, UDP-galactose, UDP-xylose and UDP-glucuronic acid, from their respective monosaccharide 1-phosphates in the presence of UTP. The enzyme could also convert glucose 1-phosphate and TTP into TDP-glucose, albeit at lower efficiency. The enzyme requires bivalent ions (Mg2+ or Mn2+) for its activity and is highly active between pH 6.5 and pH 8.0, and at 30–42 °C. The apparent Km values for the forward reaction were 177 μM (glucose 1-phosphate) and 28.4 μM (UTP) respectively. The identification of this unusual parasite enzyme with such broad substrate specificities suggests an alternative pathway that might play an essential role for nucleotide-sugar biosynthesis and for the regulation of the NDP-sugar pool in the parasite.
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Gu X, Glushka J, Yin Y, Xu Y, Denny T, Smith J, Jiang Y, Bar-Peled M. Identification of a bifunctional UDP-4-keto-pentose/UDP-xylose synthase in the plant pathogenic bacterium Ralstonia solanacearum strain GMI1000, a distinct member of the 4,6-dehydratase and decarboxylase family. J Biol Chem 2010; 285:9030-40. [PMID: 20118241 DOI: 10.1074/jbc.m109.066803] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The UDP-sugar interconverting enzymes involved in UDP-GlcA metabolism are well described in eukaryotes but less is known in prokaryotes. Here we identify and characterize a gene (RsU4kpxs) from Ralstonia solanacearum str. GMI1000, which encodes a dual function enzyme not previously described. One activity is to decarboxylate UDP-glucuronic acid to UDP-beta-l-threo-pentopyranosyl-4''-ulose in the presence of NAD(+). The second activity converts UDP-beta-l-threo-pentopyranosyl-4''-ulose and NADH to UDP-xylose and NAD(+), albeit at a lower rate. Our data also suggest that following decarboxylation, there is stereospecific protonation at the C5 pro-R position. The identification of the R. solanacearum enzyme enables us to propose that the ancestral enzyme of UDP-xylose synthase and UDP-apiose/UDP-xylose synthase was diverged to two distinct enzymatic activities in early bacteria. This separation gave rise to the current UDP-xylose synthase in animal, fungus, and plant as well as to the plant Uaxs and bacterial ArnA and U4kpxs homologs.
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Affiliation(s)
- Xiaogang Gu
- Department of Biochemistry and Molecular Biology, and the Institute of Bioinformatics, Universityof Georgia, Complex Carbohydrate Research Center, Athens, Georgia 30602, USA
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41
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Gu X, Wages CJ, Davis KE, Guyett PJ, Bar-Peled M. Enzymatic characterization and comparison of various poaceae UDP-GlcA 4-epimerase isoforms. J Biochem 2009; 146:527-34. [PMID: 19564155 DOI: 10.1093/jb/mvp099] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
UDP-alpha-D-galacturonic acid (UDP-GalA) is a key precursor for the synthesis of various bacterial and plant polysaccharides. UDP-glucuronic acid 4-epimerase (UGlcAE) catalyses the reversible conversion of UDP-alpha-D-glucuronic acid to UDP-GalA. UGlcAEs isolated from bacterial species have different biochemical properties when compared with the isoenzymes from the plant dicot species, Arabidopsis. However, little is known about the specificity of UGlcAE in Poaceae species. Therefore, we cloned and expressed in Escherichia coli several maize and rice UGlcAE genes, and compared their enzymatic properties with dicot homologs from Arabidopsis. Our data show that UGlcAE isoforms in different plant species have different enzymatic properties. For example, the Poaceae UGlcAE enzymes from rice and maize have significantly lower K(i) for UDP-xylose when compared with the Arabidopsis enzymes. The epimerases from different plant species are very specific and unlike their bacterial homolog in Klebsiella pneumoniae, can only use UDP-GlcA or UDP-GalA as their substrate. This study demonstrates that although members of the plant UGlcAE isoforms are highly conserved, the in vitro enzymatic activity of specific Poaceae isoform(s) may be regulated differently by specific nucleotide or nucleotide sugar.
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Affiliation(s)
- Xiaogang Gu
- Department of Plant Biology, University of Georgia, Athens, GA 30602-4712, USA
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42
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Yang T, Bar-Peled L, Gebhart L, Lee SG, Bar-Peled M. Identification of galacturonic acid-1-phosphate kinase, a new member of the GHMP kinase superfamily in plants, and comparison with galactose-1-phosphate kinase. J Biol Chem 2009; 284:21526-35. [PMID: 19509290 DOI: 10.1074/jbc.m109.014761] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The process of salvaging sugars released from extracellular matrix, during plant cell growth and development, is not well understood, and many molecular components remain to be identified. Here we identify and functionally characterize a unique Arabidopsis gene encoding an alpha-d-galacturonic acid-1-phosphate kinase (GalAK) and compare it with galactokinase. The GalAK gene appeared to be expressed in all tissues implicating that glycose salvage is a common catabolic pathway. GalAK catalyzes the ATP-dependent conversion of alpha-d-galacturonic acid (d-GalA) to alpha-d-galacturonic acid-1-phosphate (GalA-1-P). This sugar phosphate is then converted to UDP-GalA by a UDP-sugar pyrophosphorylase as determined by a real-time (1)H NMR-based assay. GalAK is a distinct member of the GHMP kinase family that includes galactokinase (G), homoserine kinase (H), mevalonate kinase (M), and phosphomevalonate kinase (P). Although these kinases have conserved motifs for sugar binding, nucleotide binding, and catalysis, they do have subtle difference. For example, GalAK has an additional domain near the sugar-binding motif. Using site-directed mutagenesis we established that mutation in A368S reduces phosphorylation activity by 40%; A41E mutation completely abolishes GalAK activity; Y250F alters sugar specificity and allows phosphorylation of d-glucuronic acid, the 4-epimer of GalA. Unlike many plant genes that undergo duplication, GalAK occurs as a single copy gene in vascular plants. We suggest that GalAK generates GalA-1-P from the salvaged GalA that is released during growth-dependent cell wall restructuring, or from storage tissue. The GalA-1-P itself is then available for use in the formation of UDP-GalA required for glycan synthesis.
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Affiliation(s)
- Ting Yang
- Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, and Department of Plant Biology, University of Georgia, Athens, Georgia 30602, USA
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43
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Caffall KH, Mohnen D. The structure, function, and biosynthesis of plant cell wall pectic polysaccharides. Carbohydr Res 2009; 344:1879-900. [PMID: 19616198 DOI: 10.1016/j.carres.2009.05.021] [Citation(s) in RCA: 931] [Impact Index Per Article: 62.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2008] [Revised: 05/04/2009] [Accepted: 05/06/2009] [Indexed: 11/15/2022]
Abstract
Plant cell walls consist of carbohydrate, protein, and aromatic compounds and are essential to the proper growth and development of plants. The carbohydrate components make up approximately 90% of the primary wall, and are critical to wall function. There is a diversity of polysaccharides that make up the wall and that are classified as one of three types: cellulose, hemicellulose, or pectin. The pectins, which are most abundant in the plant primary cell walls and the middle lamellae, are a class of molecules defined by the presence of galacturonic acid. The pectic polysaccharides include the galacturonans (homogalacturonan, substituted galacturonans, and RG-II) and rhamnogalacturonan-I. Galacturonans have a backbone that consists of alpha-1,4-linked galacturonic acid. The identification of glycosyltransferases involved in pectin synthesis is essential to the study of cell wall function in plant growth and development and for maximizing the value and use of plant polysaccharides in industry and human health. A detailed synopsis of the existing literature on pectin structure, function, and biosynthesis is presented.
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Affiliation(s)
- Kerry Hosmer Caffall
- University of Georgia, Department of Biochemistry and Molecular Biology and Complex Carbohydrate Research Center, Athens, 30602, United States
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44
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Guyett P, Glushka J, Gu X, Bar-Peled M. Real-time NMR monitoring of intermediates and labile products of the bifunctional enzyme UDP-apiose/UDP-xylose synthase. Carbohydr Res 2009; 344:1072-8. [PMID: 19375693 DOI: 10.1016/j.carres.2009.03.026] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 03/17/2009] [Accepted: 03/23/2009] [Indexed: 11/25/2022]
Abstract
The conversion of UDP-alpha-d-glucuronic acid to UDP-alpha-d-xylose and UDP-alpha-d-apiose by a bifunctional potato enzyme UDP-apiose/UDP-xylose synthase was studied using real-time nuclear magnetic resonance (NMR) spectroscopy. UDP-alpha-d-glucuronic acid is converted via the intermediate uridine 5'-beta-l-threo-pentapyranosyl-4''-ulose diphosphate to UDP-alpha-d-apiose and simultaneously to UDP-alpha-d-xylose. The UDP-alpha-d-apiose that is formed is unstable and is converted to alpha-d-apio-furanosyl-1,2-cyclic phosphate and UMP. High-resolution real-time NMR spectroscopy is a powerful tool for the direct and quantitative characterization of previously undetected transient and labile components formed during a complex enzyme-catalyzed reaction.
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Affiliation(s)
- Paul Guyett
- Complex Carbohydrate Research Center, and BioEnergy Science Center, 315 Riverbend Road, University of Georgia, Athens, GA 30602, USA
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45
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Joët T, Laffargue A, Salmona J, Doulbeau S, Descroix F, Bertrand B, de Kochko A, Dussert S. Metabolic pathways in tropical dicotyledonous albuminous seeds: Coffea arabica as a case study. THE NEW PHYTOLOGIST 2009; 182:146-162. [PMID: 19207685 PMCID: PMC2713855 DOI: 10.1111/j.1469-8137.2008.02742.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2008] [Accepted: 11/28/2008] [Indexed: 05/18/2023]
Abstract
* The genomic era facilitates the understanding of how transcriptional networks are interconnected to program seed development and filling. However, to date, little information is available regarding dicot seeds with a transient perisperm and a persistent, copious endosperm. Coffea arabica is the subject of increasing genomic research and is a model for nonorthodox albuminous dicot seeds of tropical origin. * The aim of this study was to reconstruct the metabolic pathways involved in the biosynthesis of the main coffee seed storage compounds, namely cell wall polysaccharides, triacylglycerols, sucrose, and chlorogenic acids. For this purpose, we integrated transcriptomic and metabolite analyses, combining real-time RT-PCR performed on 137 selected genes (of which 79 were uncharacterized in Coffea) and metabolite profiling. * Our map-drawing approach derived from model plants enabled us to propose a rationale for the peculiar traits of the coffee endosperm, such as its unusual fatty acid composition, remarkable accumulation of chlorogenic acid and cell wall polysaccharides. * Comparison with the developmental features of exalbuminous seeds described in the literature revealed that the two seed types share important regulatory mechanisms for reserve biosynthesis, independent of the origin and ploidy level of the storage tissue.
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Affiliation(s)
- Thierry Joët
- IRD, UMR DIA-PC, Pôle de Protection des Plantes97410, Saint Pierre, La Réunion, France
| | | | - Jordi Salmona
- IRD, UMR DIA-PC, Pôle de Protection des Plantes97410, Saint Pierre, La Réunion, France
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Zeng W, Chatterjee M, Faik A. UDP-Xylose-stimulated glucuronyltransferase activity in wheat microsomal membranes: characterization and role in glucurono(arabino)xylan biosynthesis. PLANT PHYSIOLOGY 2008; 147:78-91. [PMID: 18359844 PMCID: PMC2330321 DOI: 10.1104/pp.107.115576] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2007] [Accepted: 03/15/2008] [Indexed: 05/19/2023]
Abstract
Microsomal membranes from etiolated wheat (Triticum aestivum) seedlings cooperatively incorporated xylose (Xyl), arabinose, and glucuronic acid residues from their corresponding uridine 5'-diphosphosugars into an ethanol-insoluble glucurono(arabino)xylan (GAX)-like product. A glucuronyltransferase activity that is enhanced by the presence of UDP-Xyl was also identified in these microsomes. Wheat glucuronyltransferase activity was optimal at pH 7 and required manganese ions, and several lines of evidence suggest its involvement in GAX-like biosynthesis. The GAX characteristics of the 14C-product were confirmed by digestion with a purified endo-xylanase from Aspergillus awamori (endo-xylanase III) and by total acid hydrolysis, resulting in a Xyl:arabinose:glucuronic acid molar ratio of approximately 105:34:1. Endo-xylanase III released only three types of oligosaccharides in addition to free Xyl. No radiolabel was released as xylobiose, xylotriose, or xylotetraose, indicating the absence of long stretches of unbranched Xyl residues in the nascent GAX-like product. High-pH anion exchange chromatography analysis of the resulting oligosaccharides along with known arabinoxylan oligosaccharide standards suggests that a portion of the nascent GAX-like product has a relatively regular structure. The other portion of the [14C]GAX-like polymer was resistant to proteinase K, endo-polygalacturonase, and endo-xylanase III (GH11 family) but was degraded by Driselase, supporting the hypothesis that the xylan backbone in this portion of the product is most likely highly substituted. Size exclusion chromatography indicated that the nascent GAX-like polymer had an apparent molecular mass of approximately 10 to 15 kD; however, mature GAXs from wheat cell walls had larger apparent molecular masses (>66 kD).
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Affiliation(s)
- Wei Zeng
- Department of Environmental and Plant Biology, Molecular and Cellular Biology Program, Ohio University, Athens, OH 45701, USA
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Rösti J, Barton CJ, Albrecht S, Dupree P, Pauly M, Findlay K, Roberts K, Seifert GJ. UDP-glucose 4-epimerase isoforms UGE2 and UGE4 cooperate in providing UDP-galactose for cell wall biosynthesis and growth of Arabidopsis thaliana. THE PLANT CELL 2007; 19:1565-79. [PMID: 17496119 PMCID: PMC1913733 DOI: 10.1105/tpc.106.049619] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Five Arabidopsis thaliana genes that encode UDP-glucose 4-epimerase (UGE) and represent two ancient plant UGE clades might be involved in the regulation of cell wall carbohydrate biosynthesis. We tested this hypothesis in a genome-wide reverse genetic study. Despite significant contributions of each gene to total UGE activity, none was essential for normal growth on soil. uge2 uge4 displayed dramatic general growth defects, while other mutant combinations were partially aberrant. UGE2 together with UGE3 influenced pollen development. UGE2 and UGE4 synergistically influenced cell wall galactose content, which was correlated with shoot growth. UGE2 strongly and UGE1 and UGE5 lightly supported UGE4 in influencing root growth and cell wall galactose content by affecting galactan content. By contrast, only UGE4 influenced xyloglucan galactosylation in roots. Secondary hypocotyl thickening and arabinogalactan protein carbohydrate structure in xylem parenchyma depended on the combination of UGE2 and UGE4. As opposed to cell wall galactose content, tolerance to external galactose strictly paralleled total UGE activity. We suggest a gradual recruitment of individual UGE isoforms into specific roles. UGE2 and UGE4 influence growth and cell wall carbohydrate biosynthesis throughout the plant, UGE3 is specialized for pollen development, and UGE1 and UGE5 might act in stress situations.
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Affiliation(s)
- Johannes Rösti
- Department of Cell and Developmental Biology, John Ines Centre, NR4 7UH Norwich, United Kingdom
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48
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Barber C, Rösti J, Rawat A, Findlay K, Roberts K, Seifert GJ. Distinct Properties of the Five UDP-d-glucose/UDP-d-galactose 4-Epimerase Isoforms of Arabidopsis thaliana. J Biol Chem 2006; 281:17276-17285. [PMID: 16644739 DOI: 10.1074/jbc.m512727200] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Plant genomes contain genetically encoded isoforms of most nucleotide sugar interconversion enzymes. Here we show that Arabidopsis thaliana has five genes encoding functional UDP-D-glucose/UDP-D-galactose 4-epimerase (named UGE1 to UGE5). All A. thaliana UDP-d-glucose 4-epimerase isoforms are dimeric in solution, maximally active in vitro at 30-40 degrees C, and show good activity between pH 7 and pH 9. In vitro, UGE1, -3, and -5 act independently of externally added NAD+, whereas cofactor addition stimulates the activity of UGE2 and is particularly important for UGE4 activity. UGE1 and UGE3 are most efficiently inhibited by UDP. The five isoforms display kcatUDP-Gal values between 23 and 128 s(-1) and KmUDP-Gal values between 0.1 and 0.3 mm. This results in enzymatic efficiencies ranging between 97 and 890 mm(-1) s(-1) for UGE4 = UGE1 < UGE3 < UGE5 < UGE2. The KmUDP-Glc values, derived from the Haldane relationship, were 0.76 mm for UGE1, 0.56 mm for UGE4, and between 0.13 and 0.23 mm for UGE2, -3, and -5. The expression of UGE isoforms is ubiquitous and displays developmental and cell type-dependent variations. UGE1 and -3 expression patterns globally resemble enzymes involved in carbohydrate catabolism, and UGE2, -4, and -5 expression is more related to carbohydrate biosynthesis. UGE1, -2, and -4 are present in the cytoplasm, whereasUGE4 is additionally enriched close to Golgi stacks. All UGE genes tested complement the UGE4rhd1 phenotype, confer increased galactose tolerance in planta, and complement the galactose metabolization deficiency in the Saccharomyces cerevisiae gal10 mutant. We suggest that plant UGE isoforms function in different metabolic situations and that enzymatic properties, gene expression pattern, and subcellular localization contribute to the differentiation of isoform function.
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Affiliation(s)
- Christine Barber
- Department of Cell and Developmental Biology, John Innes Centre, Colney, Norwich NR4 7UH, United Kingdom
| | - Johannes Rösti
- Department of Cell and Developmental Biology, John Innes Centre, Colney, Norwich NR4 7UH, United Kingdom
| | - Arun Rawat
- Department of Cell and Developmental Biology, John Innes Centre, Colney, Norwich NR4 7UH, United Kingdom
| | - Kim Findlay
- Department of Cell and Developmental Biology, John Innes Centre, Colney, Norwich NR4 7UH, United Kingdom
| | - Keith Roberts
- Department of Cell and Developmental Biology, John Innes Centre, Colney, Norwich NR4 7UH, United Kingdom
| | - Georg J Seifert
- Department of Cell and Developmental Biology, John Innes Centre, Colney, Norwich NR4 7UH, United Kingdom.
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Ohashi T, Cramer N, Ishimizu T, Hase S. Preparation of UDP-galacturonic acid using UDP-sugar pyrophosphorylase. Anal Biochem 2006; 352:182-7. [PMID: 16581011 DOI: 10.1016/j.ab.2006.02.026] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2005] [Revised: 02/23/2006] [Accepted: 02/27/2006] [Indexed: 11/23/2022]
Abstract
UDP-galacturonic acid, the activated form of galacturonic acid (GalUA), is synthesized both de novo and by salvage pathways. The UDP-GalUA pyrophosphorylase gene involved in the salvage pathway has not been identified. Here we show that UDP-sugar pyrophosphorylase from Pisum sativum with a broad specificity has UDP-GalUA pyrophosphorylase activity. The enzyme catalyzed the formation of UDP-GalUA and pyrophosphate from GalUA 1-phosphate and UTP with an equilibrium constant value of 0.24. The recombinant UDP-sugar pyrophosphorylase had optimal pH of 6.0, and the apparent K(m) values for GalUA 1-phosphate, UTP, UDP-GalUA, and pyrophosphate were 2.27, 1.15, 0.70, and 1.26 mM, respectively. In the presence of inorganic pyrophosphatase, the recombinant enzyme produced UDP-GalUA in an 84% yield (based on the GalUA 1-phosphate substrate) on a preparative scale. Thus, this UDP-sugar pyrophosphorylase is useful for the highly efficient production of UDP-GalUA for studies on pectin biosynthesis.
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Affiliation(s)
- Takao Ohashi
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
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Sterling JD, Atmodjo MA, Inwood SE, Kumar Kolli VS, Quigley HF, Hahn MG, Mohnen D. Functional identification of an Arabidopsis pectin biosynthetic homogalacturonan galacturonosyltransferase. Proc Natl Acad Sci U S A 2006; 103:5236-41. [PMID: 16540543 PMCID: PMC1458824 DOI: 10.1073/pnas.0600120103] [Citation(s) in RCA: 192] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Indexed: 11/18/2022] Open
Abstract
Galacturonosyltransferases (GalATs) are required for the synthesis of pectin, a family of complex polysaccharides present in the cell walls of all land plants. We report the identification of a pectin GalAT (GAUT1) using peptide sequences obtained from Arabidopsis thaliana proteins partially purified for homogalacturonan (HG) alpha-1,4-GalAT activity. Transient expression of GAUT1 cDNA in the human embryonic kidney cell line HEK293 yielded uridine diphosphogalacturonic acid:GalAT activity. Polyclonal antibodies generated against GAUT1 immunoabsorbed HG alpha-1,4-GalAT activity from Arabidopsis solubilized membrane proteins. blast analysis of the Arabidopsis genome identified a family of 25 genes with high sequence similarity to GAUT1 and homologous genes in other dicots, in rice, and in Physcomitrella. Sequence alignment and phylogenetic Bayesian analysis of the Arabidopsis GAUT1-related gene family separates them into four related clades of GAUT and GAUT-like genes that are distinct from the other Arabidopsis members of glycosyltransferase family 8. The identification of GAUT1 as a HG GalAT and of the GAUT1-related gene family provides the genetic and biochemical tools required to study the function of these genes in pectin synthesis.
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Affiliation(s)
| | - Melani A. Atmodjo
- *Complex Carbohydrate Research Center and Departments of
- Biochemistry and Molecular Biology and
| | | | | | | | - Michael G. Hahn
- *Complex Carbohydrate Research Center and Departments of
- Plant Biology, University of Georgia, 315 Riverbend Road, Athens, GA 30602-4712
| | - Debra Mohnen
- *Complex Carbohydrate Research Center and Departments of
- Biochemistry and Molecular Biology and
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