1
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Xue Y, Yu C, Kang X. Quantitative and Structural Characterization of Native Lignin in Hardwood and Softwood Bark via Solid-State NMR Spectroscopy. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:18056-18066. [PMID: 39087645 DOI: 10.1021/acs.jafc.4c03469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2024]
Abstract
A major factor limiting bark's industrial use is its greater recalcitrance compared to wood. While lignin is widely recognized as a significant contributor, precise characterization of lignin in bark remains sparse, presenting a crucial gap that impedes understanding of its impact. In this study, we employed advanced solid-state nuclear magnetic resonance (NMR) spectroscopy to analyze bark samples from various species, including willow, poplar, and pine. We established and verified that lignin methoxy peak at 56 ppm serves as a reliable quantitative metric to assess lignin content, with which we calculated the lignin contents in bark are significantly reduced by more than 70% compared to those in wood. Furthermore, in situ characterization revealed significant reduction of β-ether linkage in bark lignin across species, revealing a more condensed and resistant structural configuration. Our results have substantially advanced our comprehension of the composition and structure of native lignin in tree bark.
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Affiliation(s)
- Yi Xue
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Chenjie Yu
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Xue Kang
- Institute of Drug Discovery Technology, Ningbo University, Ningbo, Zhejiang 315211, China
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2
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Cosgrove DJ. Structure and growth of plant cell walls. Nat Rev Mol Cell Biol 2024; 25:340-358. [PMID: 38102449 DOI: 10.1038/s41580-023-00691-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/15/2023] [Indexed: 12/17/2023]
Abstract
Plant cells build nanofibrillar walls that are central to plant growth, morphogenesis and mechanics. Starting from simple sugars, three groups of polysaccharides, namely, cellulose, hemicelluloses and pectins, with very different physical properties are assembled by the cell to make a strong yet extensible wall. This Review describes the physics of wall growth and its regulation by cellular processes such as cellulose production by cellulose synthase, modulation of wall pH by plasma membrane H+-ATPase, wall loosening by expansin and signalling by plant hormones such as auxin and brassinosteroid. In addition, this Review discusses the nuanced roles, properties and interactions of cellulose, matrix polysaccharides and cell wall proteins and describes how wall stress and wall loosening cooperatively result in cell wall growth.
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Affiliation(s)
- Daniel J Cosgrove
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania, USA.
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3
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Zhao W, Debnath D, Gautam I, Fernando LD, Wang T. Charting the solid-state NMR signals of polysaccharides: A database-driven roadmap. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:298-309. [PMID: 37724740 DOI: 10.1002/mrc.5397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 09/01/2023] [Accepted: 09/07/2023] [Indexed: 09/21/2023]
Abstract
Solid-state nuclear magnetic resonance (ssNMR) measurements of intact cell walls and cellular samples often generate spectra that are difficult to interpret due to the presence of many coexisting glycans and the structural polymorphism observed in native conditions. To overcome this analytical challenge, we present a statistical approach for analyzing carbohydrate signals using high-resolution ssNMR data indexed in a carbohydrate database. We generate simulated spectra to demonstrate the chemical shift dispersion and compare this with experimental data to facilitate the identification of important fungal and plant polysaccharides, such as chitin and glucans in fungi and cellulose, hemicellulose, and pectic polymers in plants. We also demonstrate that chemically distinct carbohydrates from different organisms may produce almost identical signals, highlighting the need for high-resolution spectra and validation of resonance assignments. Our study provides a means to differentiate the characteristic signals of major carbohydrates and allows us to summarize currently undetected polysaccharides in plants and fungi, which may inspire future investigations.
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Affiliation(s)
- Wancheng Zhao
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Debkumar Debnath
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Isha Gautam
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Liyanage D Fernando
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Tuo Wang
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
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4
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Petrova A, Ageeva M, Kozlova L. Root growth of monocotyledons and dicotyledons is limited by different tissues. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 116:1462-1476. [PMID: 37646760 DOI: 10.1111/tpj.16440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 08/16/2023] [Indexed: 09/01/2023]
Abstract
Plant growth and morphogenesis are determined by the mechanical properties of its cell walls. Using atomic force microscopy, we have characterized the dynamics of cell wall elasticity in different tissues in developing roots of several plant species. The elongation growth zone of roots of all species studied was distinguished by a reduced modulus of elasticity of most cell walls compared to the meristem or late elongation zone. Within the individual developmental zones of roots, there were also significant differences in the elasticity of the cell walls of the different tissues, thus identifying the tissues that limit root growth in the different species. In cereals, this is mainly the inner cortex, whereas in dicotyledons this function is performed by the outer tissues-rhizodermis and cortex. These differences result in a different behaviour of the roots of these species during longitudinal dissection. Modelling of longitudinal root dissection using measured properties confirmed the difference shown. Thus, the morphogenesis of monocotyledonous and dicotyledonous roots relies on different tissues as growth limiting, which should be taken into account when analyzing the localization of associated molecular events. At the same time, no matrix polysaccharide was found whose immunolabelling in type I or type II cell walls would predict their mechanical properties. However, assessment of the degree of anisotropy of cortical microtubules showed a striking correlation with the elasticity of the corresponding cell walls in all species studied.
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Affiliation(s)
- Anna Petrova
- Laboratory of Plant Cell Growth Mechanisms, Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, Lobachevsky Str., 2/31, 420111, Kazan, Russia
| | - Marina Ageeva
- Microscopy Cabinet, Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, Lobachevsky Str., 2/31, 420111, Kazan, Russia
| | - Liudmila Kozlova
- Laboratory of Plant Cell Growth Mechanisms, Kazan Institute of Biochemistry and Biophysics, FRC Kazan Scientific Center of RAS, Lobachevsky Str., 2/31, 420111, Kazan, Russia
- Mechanics and Civil Engineering Laboratory, University of Montpellier, 860 Rue de St - Priest, 34090, Montpellier, France
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5
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Tryfona T, Bourdon M, Delgado Marques R, Busse‐Wicher M, Vilaplana F, Stott K, Dupree P. Grass xylan structural variation suggests functional specialization and distinctive interaction with cellulose and lignin. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2023; 113:1004-1020. [PMID: 36602010 PMCID: PMC10952629 DOI: 10.1111/tpj.16096] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 12/21/2022] [Accepted: 12/23/2022] [Indexed: 06/17/2023]
Abstract
Xylan is the most abundant non-cellulosic polysaccharide in grass cell walls, and it has important structural roles. The name glucuronoarabinoxylan (GAX) is used to describe this variable hemicellulose. It has a linear backbone of β-1,4-xylose (Xyl) residues that may be substituted with α-1,2-linked (4-O-methyl)-glucuronic acid (GlcA), α-1,3-linked arabinofuranose (Araf), and sometimes acetylation at the O-2 and/or O-3 positions. The role of these substitutions remains unclear, although there is increasing evidence that they affect the way xylan interacts with other cell wall components, particularly cellulose and lignin. Here, we used substitution-dependent endo-xylanase enzymes to investigate the variability of xylan substitution in grass culm cell walls. We show that there are at least three different types of xylan: (i) an arabinoxylan with evenly distributed Araf substitutions without GlcA (AXe); (ii) a glucuronoarabinoxylan with clustered GlcA modifications (GAXc); and (iii) a highly substituted glucuronoarabinoxylan (hsGAX). Immunolocalization of AXe and GAXc in Brachypodium distachyon culms revealed that these xylan types are not restricted to a few cell types but are instead widely detected in Brachypodium cell walls. We hypothesize that there are functionally specialized xylan types within the grass cell wall. The even substitutions of AXe may permit folding and binding on the surface of cellulose fibrils, whereas the more complex substitutions of the other xylans may support a role in the matrix and interaction with other cell wall components.
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Affiliation(s)
- Theodora Tryfona
- Department of Biochemistry, School of Biological SciencesUniversity of CambridgeCambridgeCB2 1QWUK
| | | | - Rita Delgado Marques
- Department of Biochemistry, School of Biological SciencesUniversity of CambridgeCambridgeCB2 1QWUK
| | - Marta Busse‐Wicher
- Department of Biochemistry, School of Biological SciencesUniversity of CambridgeCambridgeCB2 1QWUK
| | - Francisco Vilaplana
- Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and HealthKTH Royal Institute of TechnologyStockholmSE‐10691Sweden
| | - Katherine Stott
- Department of Biochemistry, School of Biological SciencesUniversity of CambridgeCambridgeCB2 1QWUK
| | - Paul Dupree
- Department of Biochemistry, School of Biological SciencesUniversity of CambridgeCambridgeCB2 1QWUK
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6
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Zhao W, Deligey F, Chandra Shekar S, Mentink-Vigier F, Wang T. Current limitations of solid-state NMR in carbohydrate and cell wall research. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 341:107263. [PMID: 35809516 DOI: 10.1016/j.jmr.2022.107263] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 06/18/2022] [Accepted: 06/28/2022] [Indexed: 06/15/2023]
Abstract
High-resolution investigation of cell wall materials has emerged as an important application of biomolecular solid-state NMR (ssNMR). Multidimensional correlation experiments have become a standard method for obtaining sufficient spectral resolution to determine the polymorphic structure of carbohydrates and address biochemical questions regarding the supramolecular organization of cell walls. Using plant cellulose and matrix polysaccharides as examples, we will review how the multifaceted complexity of polysaccharide structure is impeding the resonance assignment process and assess the available biochemical and spectroscopic approaches that could circumvent this barrier. We will emphasize the ineffectiveness of the current methods in reconciling the ever-growing dataset and deriving structural information. We will evaluate the protocols for achieving efficient and homogeneous hyperpolarization across the cell wall material using magic-angle spinning dynamic nuclear polarization (MAS-DNP). Critical questions regarding the line-broadening effects of cell wall molecules at cryogenic temperature and by paramagnetic biradicals will be considered. Finally, the MAS-DNP method will be placed into a broader context with other structural characterization techniques, such as cryo-electron microscopy, to advance ssNMR research in carbohydrate and cell wall biomaterials.
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Affiliation(s)
- Wancheng Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Fabien Deligey
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - S Chandra Shekar
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | | | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA.
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7
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Miao Q, Nitsche C, Orton H, Overhand M, Otting G, Ubbink M. Paramagnetic Chemical Probes for Studying Biological Macromolecules. Chem Rev 2022; 122:9571-9642. [PMID: 35084831 PMCID: PMC9136935 DOI: 10.1021/acs.chemrev.1c00708] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Indexed: 12/11/2022]
Abstract
Paramagnetic chemical probes have been used in electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectroscopy for more than four decades. Recent years witnessed a great increase in the variety of probes for the study of biological macromolecules (proteins, nucleic acids, and oligosaccharides). This Review aims to provide a comprehensive overview of the existing paramagnetic chemical probes, including chemical synthetic approaches, functional properties, and selected applications. Recent developments have seen, in particular, a rapid expansion of the range of lanthanoid probes with anisotropic magnetic susceptibilities for the generation of structural restraints based on residual dipolar couplings and pseudocontact shifts in solution and solid state NMR spectroscopy, mostly for protein studies. Also many new isotropic paramagnetic probes, suitable for NMR measurements of paramagnetic relaxation enhancements, as well as EPR spectroscopic studies (in particular double resonance techniques) have been developed and employed to investigate biological macromolecules. Notwithstanding the large number of reported probes, only few have found broad application and further development of probes for dedicated applications is foreseen.
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Affiliation(s)
- Qing Miao
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
- School
of Chemistry &Chemical Engineering, Shaanxi University of Science & Technology, Xi’an710021, China
| | - Christoph Nitsche
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Henry Orton
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
- ARC
Centre of Excellence for Innovations in Peptide & Protein Science,
Research School of Chemistry, Australian
National University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Mark Overhand
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Gottfried Otting
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
- ARC
Centre of Excellence for Innovations in Peptide & Protein Science,
Research School of Chemistry, Australian
National University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Marcellus Ubbink
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
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8
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Dora S, Terrett OM, Sánchez-Rodríguez C. Plant-microbe interactions in the apoplast: Communication at the plant cell wall. THE PLANT CELL 2022; 34:1532-1550. [PMID: 35157079 PMCID: PMC9048882 DOI: 10.1093/plcell/koac040] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 01/29/2022] [Indexed: 05/20/2023]
Abstract
The apoplast is a continuous plant compartment that connects cells between tissues and organs and is one of the first sites of interaction between plants and microbes. The plant cell wall occupies most of the apoplast and is composed of polysaccharides and associated proteins and ions. This dynamic part of the cell constitutes an essential physical barrier and a source of nutrients for the microbe. At the same time, the plant cell wall serves important functions in the interkingdom detection, recognition, and response to other organisms. Thus, both plant and microbe modify the plant cell wall and its environment in versatile ways to benefit from the interaction. We discuss here crucial processes occurring at the plant cell wall during the contact and communication between microbe and plant. Finally, we argue that these local and dynamic changes need to be considered to fully understand plant-microbe interactions.
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9
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Juprasong Y, Songnuan W. Plant Stress Scenarios Differentially Affect Expression and IgE Reactivity of Grass Group-1 Allergen (β-Expansin) in Maize and Rice Pollen. FRONTIERS IN ALLERGY 2022; 3:807387. [PMID: 35386660 PMCID: PMC8974862 DOI: 10.3389/falgy.2022.807387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 01/17/2022] [Indexed: 11/26/2022] Open
Abstract
Grass pollen is among the most common outdoor aeroallergens eliciting pollen allergies throughout the world. Grass group-1 allergen or β-expansin is recognized as a major pollen allergen, particularly in the grass family Poaceae. Expression of β-expansin has been shown to be dynamic and can be influenced by environmental stresses. This study evaluated the relative expression of β-expansin and IgE-binding ability of crude pollen extract protein of rice and maize under three different stress conditions: flood, salt, and drought. After 1 week of treatments, anthers containing pollen were collected followed by RNA extraction and cDNA synthesis. To evaluate relative expression, qRT-PCR was performed using specific primers for β-expansin and reference genes. Physiological characteristics of treated and untreated maize and rice: plant height; fresh weight of anthers; number of inflorescences, anthers, and pollen grains were also recorded. To assess IgE-binding ability of proteins in rice pollen extracts, soluble crude proteins were extracted and IgE immunoblot and ELISA were performed using serum samples from grass-allergic subjects and healthy control donors. Results showed that plant height, fresh weight of anthers, number of inflorescences, anthers, and pollen grains of both maize and rice decreased significantly under drought stress conditions, but not in other conditions. Expression of β-expansin in pollen of rice showed an apparent increase in all stress treatments relative to control samples. In contrast, a significant decrease of β-expansin expression was detected in maize pollen under all stress-treated conditions. IgE-reactive protein bands from rice pollen extract proteins were ~30 kDa, as expected of the grass-group 1 protein. The intensity of IgE-reactive protein bands and the level of IgE to rice pollen proteins showed significant differences among stress conditions. In conclusion, environmental stresses—flood, salt, and drought, can elicit a change of β-expansin expression and IgE reactivity to grass group-1 pollen allergens. Changes in expression level of this gene likely reflected its importance during stress. However, the response is highly dependent on different schemes employed by each plant species.
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Affiliation(s)
- Yotin Juprasong
- Graduate Program in Toxicology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Center of Excellence on Environmental Health and Toxicology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Systems Biology of Diseases Research Unit, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Wisuwat Songnuan
- Center of Excellence on Environmental Health and Toxicology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Systems Biology of Diseases Research Unit, Faculty of Science, Mahidol University, Bangkok, Thailand
- Department of Plant Science, Faculty of Science, Mahidol University, Bangkok, Thailand
- *Correspondence: Wisuwat Songnuan
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10
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Cheung AY, Cosgrove DJ, Hara-Nishimura I, Jürgens G, Lloyd C, Robinson DG, Staehelin LA, Weijers D. A rich and bountiful harvest: Key discoveries in plant cell biology. THE PLANT CELL 2022; 34:53-71. [PMID: 34524464 PMCID: PMC8773953 DOI: 10.1093/plcell/koab234] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/01/2021] [Indexed: 05/13/2023]
Abstract
The field of plant cell biology has a rich history of discovery, going back to Robert Hooke's discovery of cells themselves. The development of microscopes and preparation techniques has allowed for the visualization of subcellular structures, and the use of protein biochemistry, genetics, and molecular biology has enabled the identification of proteins and mechanisms that regulate key cellular processes. In this review, seven senior plant cell biologists reflect on the development of this research field in the past decades, including the foundational contributions that their teams have made to our rich, current insights into cell biology. Topics covered include signaling and cell morphogenesis, membrane trafficking, cytokinesis, cytoskeletal regulation, and cell wall biology. In addition, these scientists illustrate the pathways to discovery in this exciting research field.
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Affiliation(s)
- Alice Y Cheung
- Department of Biochemistry and Molecular Biology, Molecular Cell Biology Program, Plant Biology Program, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Daniel J Cosgrove
- Department of Biology, Penn State University, University Park, Pennsylvania 16802, USA
| | | | - Gerd Jürgens
- ZMBP-Developmental Genetics, University of Tuebingen, Tuebingen 72076, Germany
| | - Clive Lloyd
- Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, UK
| | - David G Robinson
- Centre for Organismal Studies, University of Heidelberg, Heidelberg D-69120, Germany
| | - L Andrew Staehelin
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado 80309-0347, USA
| | - Dolf Weijers
- Laboratory of Biochemistry, Wageningen University, Wageningen 6708WE, the Netherlands
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11
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Narváez-Barragán DA, Tovar-Herrera OE, Guevara-García A, Serrano M, Martinez-Anaya C. Mechanisms of plant cell wall surveillance in response to pathogens, cell wall-derived ligands and the effect of expansins to infection resistance or susceptibility. FRONTIERS IN PLANT SCIENCE 2022; 13:969343. [PMID: 36082287 PMCID: PMC9445675 DOI: 10.3389/fpls.2022.969343] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 07/11/2022] [Indexed: 05/13/2023]
Abstract
Cell wall integrity is tightly regulated and maintained given that non-physiological modification of cell walls could render plants vulnerable to biotic and/or abiotic stresses. Expansins are plant cell wall-modifying proteins active during many developmental and physiological processes, but they can also be produced by bacteria and fungi during interaction with plant hosts. Cell wall alteration brought about by ectopic expression, overexpression, or exogenous addition of expansins from either eukaryote or prokaryote origin can in some instances provide resistance to pathogens, while in other cases plants become more susceptible to infection. In these circumstances altered cell wall mechanical properties might be directly responsible for pathogen resistance or susceptibility outcomes. Simultaneously, through membrane receptors for enzymatically released cell wall fragments or by sensing modified cell wall barrier properties, plants trigger intracellular signaling cascades inducing defense responses and reinforcement of the cell wall, contributing to various infection phenotypes, in which expansins might also be involved. Here, we review the plant immune response activated by cell wall surveillance mechanisms, cell wall fragments identified as responsible for immune responses, and expansin's roles in resistance and susceptibility of plants to pathogen attack.
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Affiliation(s)
| | | | | | - Mario Serrano
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
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12
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Samalova M, Gahurova E, Hejatko J. Expansin-mediated developmental and adaptive responses: A matter of cell wall biomechanics? QUANTITATIVE PLANT BIOLOGY 2022; 3:e11. [PMID: 37077967 PMCID: PMC10095946 DOI: 10.1017/qpb.2022.6] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 03/16/2022] [Accepted: 03/29/2022] [Indexed: 05/03/2023]
Abstract
Biomechanical properties of the cell wall (CW) are important for many developmental and adaptive responses in plants. Expansins were shown to mediate pH-dependent CW enlargement via a process called CW loosening. Here, we provide a brief overview of expansin occurrence in plant and non-plant species, their structure and mode of action including the role of hormone-regulated CW acidification in the control of expansin activity. We depict the historical as well as recent CW models, discuss the role of expansins in the CW biomechanics and address the developmental importance of expansin-regulated CW loosening in cell elongation and new primordia formation. We summarise the data published so far on the role of expansins in the abiotic stress response as well as the rather scarce evidence and hypotheses on the possible mechanisms underlying expansin-mediated abiotic stress resistance. Finally, we wrap it up by highlighting possible future directions in expansin research.
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Affiliation(s)
- Marketa Samalova
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Evelina Gahurova
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic
- National Centre for Biotechnological Research, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Jan Hejatko
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic
- National Centre for Biotechnological Research, Faculty of Science, Masaryk University, Brno, Czech Republic
- Author for correspondence: J. Hejatko, E-mail:
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13
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Ghassemi N, Poulhazan A, Deligey F, Mentink-Vigier F, Marcotte I, Wang T. Solid-State NMR Investigations of Extracellular Matrixes and Cell Walls of Algae, Bacteria, Fungi, and Plants. Chem Rev 2021; 122:10036-10086. [PMID: 34878762 DOI: 10.1021/acs.chemrev.1c00669] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Extracellular matrixes (ECMs), such as the cell walls and biofilms, are important for supporting cell integrity and function and regulating intercellular communication. These biomaterials are also of significant interest to the production of biofuels and the development of antimicrobial treatment. Solid-state nuclear magnetic resonance (ssNMR) and magic-angle spinning-dynamic nuclear polarization (MAS-DNP) are uniquely powerful for understanding the conformational structure, dynamical characteristics, and supramolecular assemblies of carbohydrates and other biomolecules in ECMs. This review highlights the recent high-resolution investigations of intact ECMs and native cells in many organisms spanning across plants, bacteria, fungi, and algae. We spotlight the structural principles identified in ECMs, discuss the current technical limitation and underexplored biochemical topics, and point out the promising opportunities enabled by the recent advances of the rapidly evolving ssNMR technology.
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Affiliation(s)
- Nader Ghassemi
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Alexandre Poulhazan
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States.,Department of Chemistry, Université du Québec à Montréal, Montreal H2X 2J6, Canada
| | - Fabien Deligey
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | | | - Isabelle Marcotte
- Department of Chemistry, Université du Québec à Montréal, Montreal H2X 2J6, Canada
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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14
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Petersen BL, MacAlister CA, Ulvskov P. Plant Protein O-Arabinosylation. FRONTIERS IN PLANT SCIENCE 2021; 12:645219. [PMID: 33815452 PMCID: PMC8012813 DOI: 10.3389/fpls.2021.645219] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 02/22/2021] [Indexed: 05/26/2023]
Abstract
A wide range of proteins with diverse functions in development, defense, and stress responses are O-arabinosylated at hydroxyprolines (Hyps) within distinct amino acid motifs of continuous stretches of Hyps, as found in the structural cell wall extensins, or at non-continuous Hyps as, for example, found in small peptide hormones and a variety of plasma membrane proteins involved in signaling. Plant O-glycosylation relies on hydroxylation of Prolines to Hyps in the protein backbone, mediated by prolyl-4-hydroxylase (P4H) which is followed by O-glycosylation of the Hyp C4-OH group by either galactosyltransferases (GalTs) or arabinofuranosyltranferases (ArafTs) yielding either Hyp-galactosylation or Hyp-arabinosylation. A subset of the P4H enzymes with putative preference to hydroxylation of continuous prolines and presumably all ArafT enzymes needed for synthesis of the substituted arabinose chains of one to four arabinose units, have been identified and functionally characterized. Truncated root-hair phenotype is one common denominator of mutants of Hyp formation and Hyp-arabinosylation glycogenes, which act on diverse groups of O-glycosylated proteins, e.g., the small peptide hormones and cell wall extensins. Dissection of different substrate derived effects may not be regularly feasible and thus complicate translation from genotype to phenotype. Recently, lack of proper arabinosylation on arabinosylated proteins has been shown to influence their transport/fate in the secretory pathway, hinting to an additional layer of functionality of O-arabinosylation. Here, we provide an update on the prevalence and types of O-arabinosylated proteins and the enzymatic machinery responsible for their modifications.
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Affiliation(s)
- Bent Larsen Petersen
- Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Cora A. MacAlister
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | - Peter Ulvskov
- Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
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15
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Wilson LA, Deligey F, Wang T, Cosgrove DJ. Saccharide analysis of onion outer epidermal walls. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:66. [PMID: 33722273 PMCID: PMC7962260 DOI: 10.1186/s13068-021-01923-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 03/06/2021] [Indexed: 05/07/2023]
Abstract
BACKGROUND Epidermal cell walls have special structural and biological roles in the life of the plant. Typically they are multi-ply structures encrusted with waxes and cutin which protect the plant from dehydration and pathogen attack. These characteristics may also reduce chemical and enzymatic deconstruction of the wall for sugar analysis and conversion to biofuels. We have assessed the saccharide composition of the outer epidermal wall of onion scales with different analytical methods. This wall is a particularly useful model for cell wall imaging and mechanics. RESULTS Epidermal walls were depolymerized by acidic methanolysis combined with 2M trifluoracetic acid hydrolysis and the resultant sugars were analyzed by high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Total sugar yields based on wall dry weight were low (53%). Removal of waxes with chloroform increased the sugar yields to 73% and enzymatic digestion did not improve these yields. Analysis by gas chromatography/mass spectrometry (GC/MS) of per-O-trimethylsilyl (TMS) derivatives of the sugar methyl glycosides produced by acidic methanolysis gave a high yield for galacturonic acid (GalA) but glucose (Glc) was severely reduced. In a complementary fashion, GC/MS analysis of methyl alditols produced by permethylation gave substantial yields for glucose and other neutral sugars, but GalA was severely reduced. Analysis of the walls by 13C solid-state NMR confirmed and extended these results and revealed 15% lipid content after chloroform extraction (potentially cutin and unextractable waxes). CONCLUSIONS Although exact values vary with the analytical method, our best estimate is that polysaccharide in the outer epidermal wall of onion scales is comprised of homogalacturonan (~ 50%), cellulose (~ 20%), galactan (~ 10%), xyloglucan (~ 10%) and smaller amounts of other polysaccharides. Low yields of specific monosaccharides by some methods may be exaggerated in epidermal walls impregnated with waxes and cutin and call for cautious interpretation of the results.
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Affiliation(s)
- Liza A Wilson
- Center for Lignocellulose Structure and Formation, Department of Biology, Pennsylvania State University, 208 Mueller Lab, University Park, PA, 16802, USA.
| | - Fabien Deligey
- Department of Chemistry, Louisiana State University, 133 Choppin Hall, Baton Rouge, LA, 70803, USA
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, 133 Choppin Hall, Baton Rouge, LA, 70803, USA
| | - Daniel J Cosgrove
- Center for Lignocellulose Structure and Formation, Department of Biology, Pennsylvania State University, 208 Mueller Lab, University Park, PA, 16802, USA
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16
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Effects of lamellar organization and arabinoxylan substitution rate on the properties of films simulating wheat grain aleurone cell wall. Carbohydr Polym 2021; 270:117819. [PMID: 34364586 DOI: 10.1016/j.carbpol.2021.117819] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 02/08/2021] [Accepted: 02/10/2021] [Indexed: 11/20/2022]
Abstract
Herein, we evaluated the properties of alternate arabinoxylan (AX)/(1→3) (1→4)-β-D-glucan (BG) multilayer films. AX was extracted from wheat at three growth stages and single-component and alternate overlapping multilayer films were prepared. The physical properties, water diffusion rate, and water mobility of multilayer films during water absorption and desorption were studied. There were significant differences in the AX content and arabinose-to-xylose ratio at different growth stages. The LAX/BG multilayer films showed excellent thermal stability and mechanical properties with an increase in the relative humidity. The AX multilayer films with a low substitution rate showed a better water-binding capacity, whereas water molecules in films with a high substitution rate showed higher mobility. Therefore, a low substitution rate AX and AX/BG composite structure can improve the thermodynamic properties of multilayer films, but limit water mobility. We provide new insights on the physicochemical properties and water-regulation effects of wheat cell wall.
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17
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Zhao W, Kirui A, Deligey F, Mentink-Vigier F, Zhou Y, Zhang B, Wang T. Solid-state NMR of unlabeled plant cell walls: high-resolution structural analysis without isotopic enrichment. BIOTECHNOLOGY FOR BIOFUELS 2021; 14:14. [PMID: 33413580 PMCID: PMC7792314 DOI: 10.1186/s13068-020-01858-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 12/11/2020] [Indexed: 05/05/2023]
Abstract
BACKGROUND Multidimensional solid-state nuclear magnetic resonance (ssNMR) spectroscopy has emerged as an indispensable technique for resolving polymer structure and intermolecular packing in primary and secondary plant cell walls. Isotope (13C) enrichment provides feasible sensitivity for measuring 2D/3D correlation spectra, but this time-consuming procedure and its associated expenses have restricted the application of ssNMR in lignocellulose analysis. RESULTS Here, we present a method that relies on the sensitivity-enhancing technique Dynamic Nuclear Polarization (DNP) to eliminate the need for 13C-labeling. With a 26-fold sensitivity enhancement, a series of 2D 13C-13C correlation spectra were successfully collected using the unlabeled stems of wild-type Oryza sativa (rice). The atomic resolution allows us to observe a large number of intramolecular cross peaks for fully revealing the polymorphic structure of cellulose and xylan. NMR relaxation and dipolar order parameters further suggest a sophisticated change of molecular motions in a ctl1 ctl2 double mutant: both cellulose and xylan have become more dynamic on the nanosecond and microsecond timescale, but the motional amplitudes are uniformly small for both polysaccharides. CONCLUSIONS By skipping isotopic labeling, the DNP strategy demonstrated here is universally extendable to all lignocellulose materials. This time-efficient method has landed the technical foundation for understanding polysaccharide structure and cell wall assembly in a large variety of plant tissues and species.
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Affiliation(s)
- Wancheng Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Alex Kirui
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Fabien Deligey
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | | | - Yihua Zhou
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Baocai Zhang
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA.
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18
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Lohoff C, Buchholz PCF, Le Roes-Hill M, Pleiss J. Expansin Engineering Database: A navigation and classification tool for expansins and homologues. Proteins 2020; 89:149-162. [PMID: 32862462 DOI: 10.1002/prot.26001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 06/16/2020] [Accepted: 08/25/2020] [Indexed: 11/07/2022]
Abstract
Expansins have the remarkable ability to loosen plant cell walls and cellulose material without showing catalytic activity and therefore have potential applications in biomass degradation. To support the study of sequence-structure-function relationships and the search for novel expansins, the Expansin Engineering Database (ExED, https://exed.biocatnet.de) collected sequence and structure data on expansins from Bacteria, Fungi, and Viridiplantae, and expansin-like homologues such as carbohydrate binding modules, glycoside hydrolases, loosenins, swollenins, cerato-platanins, and EXPNs. Based on global sequence alignment and protein sequence network analysis, the sequences are highly diverse. However, many similarities were found between the expansin domains. Newly created profile hidden Markov models of the two expansin domains enable standard numbering schemes, comprehensive conservation analyses, and genome annotation. Conserved key amino acids in the expansin domains were identified, a refined classification of expansins and carbohydrate binding modules was proposed, and new sequence motifs facilitate the search of novel candidate genes and the engineering of expansins.
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Affiliation(s)
- Caroline Lohoff
- Institute of Biochemistry and Technical Biochemistry, University of Stuttgart, Stuttgart, Germany
| | - Patrick C F Buchholz
- Institute of Biochemistry and Technical Biochemistry, University of Stuttgart, Stuttgart, Germany
| | - Marilize Le Roes-Hill
- Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Cape Town, South Africa
| | - Jürgen Pleiss
- Institute of Biochemistry and Technical Biochemistry, University of Stuttgart, Stuttgart, Germany
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19
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Valenzuela-Riffo F, Parra-Palma C, Ramos P, Morales-Quintana L. Molecular and structural insights into FaEXPA5, an alpha-expansin protein related with cell wall disassembly during ripening of strawberry fruit. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 154:581-589. [PMID: 32711363 DOI: 10.1016/j.plaphy.2020.06.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 06/05/2020] [Accepted: 06/05/2020] [Indexed: 06/11/2023]
Abstract
Cell wall modification is one of the main factors that produce the tissue softening during ripening of many fruit including strawberry (Fragaria x ananassa). Expansins have been studied for over 20 years as a class of the important cell growth regulators, and in the last years these have been related with the fruit softening. In strawberry, five partial sequences of the expansins genes were described in the past, this analysis showed that FaEXP5 partial gene was present throughout fruit development, but was more strongly expressed during ripening. Now, we reported the full length of this α-expansin (FaEXPA5), whose had been related with fruit softening, and the protein structural was described by homology model. Their transcript accumulation during softening was confirmed by qRT-PCR, displaying a high accumulation rate during fruit ripening. In silico analysis of promoter sequence showed four ABA and two auxin cis-regulatory elements, potentially responsible for the expression patterns observed in response to the hormone treatments. Additionally, 3D protein model displayed two domains and one open groove characteristic of expansin structures. The protein-ligand interactions were evaluated by molecular dynamic (MD) simulation using three different long structure ligands (a cellulose fiber, a xyloglucan fiber (XXXG type), and a pectin fiber as control). Favorable interactions were observed with xyloglucan and cellulose, being cellulose the best ligand with lower RMSD value. Additionally, MD simulations showed that FaEXPA5 can interact with the ligands through residues present in the open groove along the two domains.
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Affiliation(s)
- Felipe Valenzuela-Riffo
- Programa de Doctorado en Ciencias Mención Ingeniería Genética, Instituto de Ciencias Biológicas, Universidad de Talca, Chile
| | - Carolina Parra-Palma
- Programa de Doctorado en Ciencias Mención Ingeniería Genética, Instituto de Ciencias Biológicas, Universidad de Talca, Chile
| | - Patricio Ramos
- Instituto de Ciencias Biológicas, Universidad de Talca, Chile; Núcleo Científico Multidisciplinario-DI, Universidad de Talca, Chile.
| | - Luis Morales-Quintana
- Multidisciplinary Agroindustry Research Laboratory, Instituto de Ciencias Biomédica, Facultad Ciencias de La Salud, Universidad Autónoma de Chile, Talca, Chile.
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20
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Elongating maize root: zone-specific combinations of polysaccharides from type I and type II primary cell walls. Sci Rep 2020; 10:10956. [PMID: 32616810 PMCID: PMC7331734 DOI: 10.1038/s41598-020-67782-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 06/12/2020] [Indexed: 11/09/2022] Open
Abstract
The dynamics of cell wall polysaccharides may modulate the cell wall mechanics and thus control the expansion growth of plant cells. The unique composition of type II primary cell wall characteristic of grasses suggests that they employ specific mechanisms for cell enlargement. We characterized the transcriptomes in five zones along maize root, clustered the expression of genes for numerous glycosyltransferases and performed extensive immunohistochemical analysis to relate the changes in cell wall polysaccharides to critical stages of cell development in Poaceae. Specific patterns of cell wall formation differentiate the initiation, realization and cessation of elongation growth. Cell walls of meristem and early elongation zone represent a mixture of type I and type II specific polysaccharides. Xyloglucans and homogalacturonans are synthesized there actively together with mixed-linkage glucans and glucuronoarabinoxylans. Rhamnogalacturonans-I with the side-chains of branched 1,4-galactan and arabinan persisted in cell walls throughout the development. Thus, the machinery to generate the type I primary cell wall constituents is completely established and operates. The expression of glycosyltransferases responsible for mixed-linkage glucan and glucuronoarabinoxylan synthesis peaks at active or late elongation. These findings widen the number of jigsaw pieces which should be put together to solve the puzzle of grass cell growth.
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21
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Chakraborty A, Deligey F, Quach J, Mentink-Vigier F, Wang P, Wang T. Biomolecular complex viewed by dynamic nuclear polarization solid-state NMR spectroscopy. Biochem Soc Trans 2020; 48:1089-1099. [PMID: 32379300 PMCID: PMC7565284 DOI: 10.1042/bst20191084] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 04/17/2020] [Accepted: 04/20/2020] [Indexed: 01/07/2023]
Abstract
Solid-state nuclear magnetic resonance (ssNMR) is an indispensable tool for elucidating the structure and dynamics of insoluble and non-crystalline biomolecules. The recent advances in the sensitivity-enhancing technique magic-angle spinning dynamic nuclear polarization (MAS-DNP) have substantially expanded the territory of ssNMR investigations and enabled the detection of polymer interfaces in a cellular environment. This article highlights the emerging MAS-DNP approaches and their applications to the analysis of biomolecular composites and intact cells to determine the folding pathway and ligand binding of proteins, the structural polymorphism of low-populated biopolymers, as well as the physical interactions between carbohydrates, proteins, and lignin. These structural features provide an atomic-level understanding of many cellular processes, promoting the development of better biomaterials and inhibitors. It is anticipated that the capabilities of MAS-DNP in biomolecular and biomaterial research will be further enlarged by the rapid development of instrumentation and methodology.
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Affiliation(s)
- Arnab Chakraborty
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Fabien Deligey
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Jenny Quach
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
| | | | - Ping Wang
- Department of Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
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22
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Zhao W, Fernando LD, Kirui A, Deligey F, Wang T. Solid-state NMR of plant and fungal cell walls: A critical review. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2020; 107:101660. [PMID: 32251983 DOI: 10.1016/j.ssnmr.2020.101660] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 03/17/2020] [Indexed: 05/22/2023]
Abstract
The cell walls of plants and microbes are a central source for bio-renewable energy and the major targets of antibiotics and antifungal agents. It is highly challenging to determine the molecular structure of complex carbohydrates, protein and lignin, and their supramolecular assembly in intact cell walls. This article selectively highlights the recent breakthroughs that employ 13C/15N solid-state NMR techniques to elucidate the architecture of fungal cell walls in Aspergillus fumigatus and the primary and secondary cell walls in a large variety of plant species such as Arabidopsis, Brachypodium, maize, and spruce. Built upon these pioneering studies, we further summarize the underexplored aspects of fungal and plant cell walls. The new research opportunities introduced by innovative methods, such as the detection of proton and quadrupolar nuclei on ultrahigh-field magnets and under fast magic-angle spinning, paramagnetic probes, natural-abundance DNP, and software development, are also critically discussed.
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Affiliation(s)
- Wancheng Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Liyanage D Fernando
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Alex Kirui
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Fabien Deligey
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA.
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23
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Narváez-Barragán DA, Tovar-Herrera OE, Torres M, Rodríguez M, Humphris S, Toth IK, Segovia L, Serrano M, Martínez-Anaya C. Expansin-like Exl1 from Pectobacterium is a virulence factor required for host infection, and induces a defence plant response involving ROS, and jasmonate, ethylene and salicylic acid signalling pathways in Arabidopsis thaliana. Sci Rep 2020; 10:7747. [PMID: 32385404 PMCID: PMC7210985 DOI: 10.1038/s41598-020-64529-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 04/17/2020] [Indexed: 01/09/2023] Open
Abstract
Expansins are encoded by some phytopathogenic bacteria and evidence indicates that they act as virulence factors for host infection. Here we analysed the expression of exl1 by Pectobacterium brasiliense and Pectobacterium atrosepticum. In both, exl1 gene appears to be under quorum sensing control, and protein Exl1 can be observed in culture medium and during plant infection. Expression of exl1 correlates with pathogen virulence, where symptoms are reduced in a Δexl1 mutant strain of P. atrosepticum. As well as Δexl1 exhibiting less maceration of potato plants, fewer bacteria are observed at distance from the inoculation site. However, bacteria infiltrated into the plant tissue are as virulent as the wild type, suggesting that this is due to alterations in the initial invasion of the tissue. Additionally, swarming from colonies grown on MacConkey soft agar was delayed in the mutant in comparison to the wild type. We found that Exl1 acts on the plant tissue, probably by remodelling of a cell wall component or altering the barrier properties of the cell wall inducing a plant defence response, which results in the production of ROS and the induction of marker genes of the JA, ET and SA signalling pathways in Arabidopsis thaliana. Exl1 inactive mutants fail to trigger such responses. This defence response is protective against Pectobacterium brasiliense and Botrytis cinerea in more than one plant species.
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Affiliation(s)
- Delia A Narváez-Barragán
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico
| | - Omar E Tovar-Herrera
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico
- Department of Biomolecular Sciences, The Weizmann Institute of Science, 7610001, Rehovot, Israel
| | - Martha Torres
- Centro de Ciencias Genómicas. Universidad Nacional Autónoma de México, 62110, Cuernavaca, Morelos, Mexico
| | - Mabel Rodríguez
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico
| | - Sonia Humphris
- The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Ian K Toth
- The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Lorenzo Segovia
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico
| | - Mario Serrano
- Centro de Ciencias Genómicas. Universidad Nacional Autónoma de México, 62110, Cuernavaca, Morelos, Mexico
| | - Claudia Martínez-Anaya
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210, Cuernavaca, Morelos, Mexico.
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24
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Kang X, Zhao W, Dickwella Widanage MC, Kirui A, Ozdenvar U, Wang T. CCMRD: a solid-state NMR database for complex carbohydrates. JOURNAL OF BIOMOLECULAR NMR 2020; 74:239-245. [PMID: 32125579 DOI: 10.1007/s10858-020-00304-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 01/27/2020] [Indexed: 05/03/2023]
Abstract
Carbohydrates are essential to various life activities in living organisms and serve as the central component in many biomaterials. As an emerging technique with steadily improving resolution, solid-state Nuclear Magnetic Resonance (NMR) spectroscopy has the unique capability in revealing the polymorphic structure and heterogeneous dynamics of insoluble complex carbohydrates. Here, we report the first solid-state NMR database for complex carbohydrates, Complex Carbohydrates Magnetic Resonance Database (CCMRD). This database currently holds the chemical shift information of more than four hundred solid-state NMR compounds and expects rapid expansion. CCMRD provides open portals for data deposition and supports search options based on NMR chemical shifts, carbohydrate names, and compound classes. With the timely implementation, this platform will facilitate spectral analysis and structure determination of carbohydrates and promote software development to benefit the research community. The database is freely accessible at www.ccmrd.org.
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Affiliation(s)
- Xue Kang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA.
| | - Wancheng Zhao
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | | | - Alex Kirui
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Uluc Ozdenvar
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA.
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25
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Naulin PA, Armijo GI, Vega AS, Tamayo KP, Gras DE, de la Cruz J, Gutiérrez RA. Nitrate Induction of Primary Root Growth Requires Cytokinin Signaling in Arabidopsis thaliana. PLANT & CELL PHYSIOLOGY 2020; 61:342-352. [PMID: 31730198 DOI: 10.1093/pcp/pcz199] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 10/16/2019] [Indexed: 05/27/2023]
Abstract
Nitrate can act as a potent signal to control growth and development in plants. In this study, we show that nitrate is able to stimulate primary root growth via increased meristem activity and cytokinin signaling. Cytokinin perception and biosynthesis mutants displayed shorter roots as compared with wild-type plants when grown with nitrate as the only nitrogen source. Histological analysis of the root tip revealed decreased cell division and elongation in the cytokinin receptor double mutant ahk2/ahk4 as compared with wild-type plants under a sufficient nitrate regime. Interestingly, a nitrate-dependent root growth arrest was observed between days 5 and 6 after sowing. Wild-type plants were able to recover from this growth arrest, while cytokinin signaling or biosynthesis mutants were not. Transcriptome analysis revealed significant changes in gene expression after, but not before, this transition in contrasting genotypes and nitrate regimes. We identified genes involved in both cell division and elongation as potentially important for primary root growth in response to nitrate. Our results provide evidence linking nitrate and cytokinin signaling for the control of primary root growth in Arabidopsis thaliana.
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Affiliation(s)
- Pamela A Naulin
- Departamento de Genética Molecular y Microbiología, FONDAP Center for Genome Regulation, Millennium Institute for Integrative Biology (iBio), Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Grace I Armijo
- Departamento de Genética Molecular y Microbiología, FONDAP Center for Genome Regulation, Millennium Institute for Integrative Biology (iBio), Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Andrea S Vega
- Departamento de Genética Molecular y Microbiología, FONDAP Center for Genome Regulation, Millennium Institute for Integrative Biology (iBio), Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Karem P Tamayo
- Departamento de Genética Molecular y Microbiología, FONDAP Center for Genome Regulation, Millennium Institute for Integrative Biology (iBio), Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Diana E Gras
- Departamento de Genética Molecular y Microbiología, FONDAP Center for Genome Regulation, Millennium Institute for Integrative Biology (iBio), Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Javiera de la Cruz
- Departamento de Genética Molecular y Microbiología, FONDAP Center for Genome Regulation, Millennium Institute for Integrative Biology (iBio), Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | - Rodrigo A Gutiérrez
- Departamento de Genética Molecular y Microbiología, FONDAP Center for Genome Regulation, Millennium Institute for Integrative Biology (iBio), Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
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26
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Kim YJ, Zhang D, Jung KH. Molecular Basis of Pollen Germination in Cereals. TRENDS IN PLANT SCIENCE 2019; 24:1126-1136. [PMID: 31610991 DOI: 10.1016/j.tplants.2019.08.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/22/2019] [Accepted: 08/22/2019] [Indexed: 05/22/2023]
Abstract
Understanding the molecular basis of pollen germination in cereals holds great potential to improve yield. Pollen, a highly specialized haploid male gametophyte, transports sperm cells through a pollen tube to the female ovule for fertilization, directly determining grain yield in cereal crops. Although insights into the regulation of pollen germination and gamete interaction have advanced rapidly in the model Arabidopsis thaliana (arabidopsis), the molecular mechanisms in monocot cereals remain largely unknown. Recently, pollen-specific genome-wide and mutant analyses in rice and maize have extended our understanding of monocot regulatory components. We highlight conserved and diverse mechanisms underlying pollen hydration, germination, and tube growth in cereals that provide ideas for translating this research from arabidopsis. Recent developments in gene-editing systems may facilitate further functional genetic research.
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Affiliation(s)
- Yu-Jin Kim
- Graduate School of Biotechnology and Crop Biotech Institute, Kyung Hee University, Yongin 17104, Korea
| | - Dabing Zhang
- Graduate School of Biotechnology and Crop Biotech Institute, Kyung Hee University, Yongin 17104, Korea; Joint International Research Laboratory of Metabolic and Developmental Sciences, Shanghai Jiao Tong University-University of Adelaide Joint Centre for Agriculture and Health, State Key Laboratory of Hybrid Rice, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China; School of Agriculture, Food, and Wine, University of Adelaide, South Australia 5064, Australia.
| | - Ki-Hong Jung
- Graduate School of Biotechnology and Crop Biotech Institute, Kyung Hee University, Yongin 17104, Korea.
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27
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Hepler NK, Cosgrove DJ. Directed
in vitro
evolution of bacterial expansin BsEXLX1 for higher cellulose binding and its consequences for plant cell wall‐loosening activities. FEBS Lett 2019; 593:2545-2555. [DOI: 10.1002/1873-3468.13528] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 06/28/2019] [Accepted: 07/02/2019] [Indexed: 11/09/2022]
Affiliation(s)
- Nathan K. Hepler
- Huck Institutes of the Life Sciences The Pennsylvania State University University Park PA USA
- Department of Biology The Pennsylvania State University University Park PA USA
| | - Daniel J. Cosgrove
- Huck Institutes of the Life Sciences The Pennsylvania State University University Park PA USA
- Department of Biology The Pennsylvania State University University Park PA USA
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28
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Rubianes D, Valdivia ER, Revilla G, Zarra I, Sampedro J. Xyloglucan exoglycosidases in the monocot model Brachypodium distachyon and the conservation of xyloglucan disassembly in angiosperms. PLANT MOLECULAR BIOLOGY 2019; 100:495-509. [PMID: 31028613 DOI: 10.1007/s11103-019-00875-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 04/15/2019] [Indexed: 06/09/2023]
Abstract
Brachypodium distachyon has a full set of exoglycosidases active on xyloglucan, including α-xylosidase, β-galactosidase, soluble and membrane-bound β-glucosidases and two α-fucosidases. However, unlike in Arabidopsis, both fucosidases are likely cytosolic. Xyloglucan is present in primary walls of all angiosperms. While in most groups it regulates cell wall extension, in Poaceae its role is still unclear. Five exoglycosidases participate in xyloglucan hydrolysis in Arabidopsis: α-xylosidase, β-galactosidase, α-fucosidase, soluble β-glucosidase and GPI-anchored β-glucosidase. Mutants in the corresponding genes show alterations in xyloglucan composition. In this work putative orthologs in the model grass Brachypodium distachyon were tested for their ability to complement Arabidopsis mutants. Xylosidase and galactosidase mutants were complemented, respectively, by BdXYL1 (Bd2g02070) and BdBGAL1 (Bd2g56607). BdBGAL1, unlike other xyloglucan β-galactosidases, is able to remove both galactoses from XLLG oligosaccharides. In addition, soluble β-glucosidase BdBGLC1 (Bd1g08550) complemented a glucosidase mutant. Closely related BdBGLC2 (Bd2g51280), which has a putative GPI-anchor sequence, was found associated with the plasma membrane and only a truncated version without GPI-anchor complemented the mutant, proving that Brachypodium also has soluble and membrane-bound xyloglucan glucosidases. Both BdXFUC1 (Bd3g25226) and BdXFUC2 (Bd1g28366) can hydrolyze fucose from xyloglucan oligosaccharides but were unable to complement a fucosidase mutant. Fluorescent protein fusions of BdXFUC1 localized to the cytosol and both proteins lack a signal peptide. Signal peptides appear to have evolved only in some eudicot lineages of this family, like the one leading to Arabidopsis. These results could be explained if cytosolic xyloglucan α-fucosidases are the ancestral state in angiosperms, with fucosylated oligosaccharides transported across the plasma membrane.
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Affiliation(s)
- Diego Rubianes
- Dpto. Biología Funcional, Facultad de Biología, Universidade de Santiago, 15782, Santiago de Compostela, Spain
| | - Elene R Valdivia
- Dpto. Biología Funcional, Facultad de Biología, Universidade de Santiago, 15782, Santiago de Compostela, Spain
| | - Gloria Revilla
- Dpto. Biología Funcional, Facultad de Biología, Universidade de Santiago, 15782, Santiago de Compostela, Spain
| | - Ignacio Zarra
- Dpto. Biología Funcional, Facultad de Biología, Universidade de Santiago, 15782, Santiago de Compostela, Spain
| | - Javier Sampedro
- Dpto. Biología Funcional, Facultad de Biología, Universidade de Santiago, 15782, Santiago de Compostela, Spain.
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29
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Cosgrove DJ. Nanoscale structure, mechanics and growth of epidermal cell walls. CURRENT OPINION IN PLANT BIOLOGY 2018; 46:77-86. [PMID: 30142487 DOI: 10.1016/j.pbi.2018.07.016] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/19/2018] [Accepted: 07/25/2018] [Indexed: 05/02/2023]
Abstract
This article briefly reviews recent advances in nano-scale and micro-scale assessments of primary cell wall structure, mechanical behaviors and expansive growth. Cellulose microfibrils have hydrophobic and hydrophilic faces which may selectively bind different matrix polysaccharides and adjacent microfibrils. These distinctive binding interactions may guide partially aligned cellulose microfibrils in primary cell walls to form a planar, load-bearing network within each lamella of polylamellate walls. Consideration of expansive growth of cross-lamellate walls leads to a surprising inference: side-by-side sliding of microfibrils may be a key rate-limiting physical step, potentially targeted by specific wall loosening agents. Atomic force microscopy shows different patterns of microfibril movement during force-driven extension versus enzymatic loosening. Consequently, simulations of cell growth as elastic deformation of isotropic cell walls may need to be augmented to incorporate the distinctive behavior of growing cell walls.
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Affiliation(s)
- Daniel J Cosgrove
- Department of Biology, Penn State University, University Park, PA 16803, USA.
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30
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Gelenter MD, Hong M. Efficient 15N- 13C Polarization Transfer by Third-Spin-Assisted Pulsed Cross-Polarization Magic-Angle-Spinning NMR for Protein Structure Determination. J Phys Chem B 2018; 122:8367-8379. [PMID: 30106585 DOI: 10.1021/acs.jpcb.8b06400] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
We introduce a pulsed third-spin-assisted recoupling experiment that produces high-intensity long-range 15N-13C cross peaks using low radiofrequency (rf) energy. This Proton-Enhanced Rotor-echo Short-Pulse IRradiATION Cross-Polarization (PERSPIRATIONCP) pulse sequence operates with the same principle as the Proton-Assisted Insensitive-Nuclei Cross-Polarization (PAINCP) experiment but uses only a fraction of the rf energy by replacing continuous-wave 13C and 15N irradiation with rotor-echo 90° pulses. Using formyl-Met-Leu-Phe (f-MLF) and β1 immunoglobulin binding domain of protein G (GB1) as model proteins, we demonstrate experimentally how PERSPIRATIONCP polarization transfer depends on the CP contact time, rf power, pulse flip angle, and 13C carrier frequency and compare the PERSPIRATIONCP performance with the performances of PAINCP, RESPIRATIONCP, and SPECIFICCP for measuring 15N-13C cross peaks. PERSPIRATIONCP achieves long-range 15N-13C transfer and yields higher cross peak-intensities than that of the other techniques. Numerical simulations reproduce the experimental trends and moreover indicate that PERSPIRATIONCP relies on 15N-1H and 13C-1H dipolar couplings rather than 15N-13C dipolar coupling for polarization transfer. Therefore, PERSPIRATIONCP is an rf-efficient and higher-sensitivity alternative to PAINCP for measuring long-range 15N-13C correlations, which are essential for protein resonance assignment and structure determination. Using cross peaks from two PERSPIRATIONCP 15N-13C correlation spectra as the sole distance restraints, supplemented with (φ, ψ) torsion angles obtained from chemical shifts, we calculated the GB1 structure and obtained a backbone root-mean-square deviation of 2.0 Å from the high-resolution structure of the protein. Therefore, this rf-efficient PERSPIRATIONCP method is useful for obtaining many long-range distance restraints for protein structure determination.
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Affiliation(s)
- Martin D Gelenter
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Mei Hong
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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31
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Kang X, Kirui A, Muszyński A, Widanage MCD, Chen A, Azadi P, Wang P, Mentink-Vigier F, Wang T. Molecular architecture of fungal cell walls revealed by solid-state NMR. Nat Commun 2018; 9:2747. [PMID: 30013106 PMCID: PMC6048167 DOI: 10.1038/s41467-018-05199-0] [Citation(s) in RCA: 174] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 06/21/2018] [Indexed: 12/12/2022] Open
Abstract
The high mortality of invasive fungal infections, and the limited number and inefficacy of antifungals necessitate the development of new agents with novel mechanisms and targets. The fungal cell wall is a promising target as it contains polysaccharides absent in humans, however, its molecular structure remains elusive. Here we report the architecture of the cell walls in the pathogenic fungus Aspergillus fumigatus. Solid-state NMR spectroscopy, assisted by dynamic nuclear polarization and glycosyl linkage analysis, reveals that chitin and α-1,3-glucan build a hydrophobic scaffold that is surrounded by a hydrated matrix of diversely linked β-glucans and capped by a dynamic layer of glycoproteins and α-1,3-glucan. The two-domain distribution of α-1,3-glucans signifies the dual functions of this molecule: contributing to cell wall rigidity and fungal virulence. This study provides a high-resolution model of fungal cell walls and serves as the basis for assessing drug response to promote the development of wall-targeted antifungals.
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Affiliation(s)
- Xue Kang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Alex Kirui
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Artur Muszyński
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA
| | | | - Adrian Chen
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA
| | - Ping Wang
- Departments of Pediatrics, and Microbiology, Immunology and Parasitology, Louisiana State University Health Sciences Center, New Orleans, LA, 70112, USA
| | | | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, 70803, USA.
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32
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The molecular allergology of subtropical grass pollen. Mol Immunol 2018; 100:126-135. [PMID: 29778490 DOI: 10.1016/j.molimm.2018.03.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 03/19/2018] [Indexed: 11/22/2022]
Abstract
Grass pollens are amongst the most important aeroallergen sources world-wide triggering allergic rhinoconjunctivitis and asthma in sensitised patients. Much of what we know about the allergen components of grasses is informed by research on pollen of temperate (Pooideae) species that are abundant in the temperate climate zones. However, climate changes are altering the biogeographical distribution as well as timing and allergenicity of grass pollens. This provides an impetus for better understanding of the contribution of subtropical subfamilies of grasses to pollen allergy globally. Pollen of Chloridoideae (e.g. Cynodon dactylon; Bermuda grass) and Panicoideae (e.g. Paspalum notatum; Bahia grass or Sorghum halepense; Johnson grass) subfamilies are clinically important in subtropical zones of Australia, Asia, India, Africa, and America. These grasses differ ecologically and phylogenetically from temperate grasses and, importantly their allergen composition is qualitatively different. For example, subtropical grass pollens appear to lack the major group 5 grass pollen allergen family. In this review we summarize current knowledge of the epidemiology and immunology of subtropical Chloridoideae and Pancoideae pollen allergens, describe the biochemical characteristics of known isoforms and variants as well as properties and structures of subtropical pollen allergen components. Whilst only one subtropical allergen component; Cyn d 1 of Bermuda grass pollen, is available commercially for diagnostic use, in a natural purified form, a number of allergens of Panicoideae grass pollen; Zea m 1, Zea m 3 and Zea m 13 of maize, Pas n 1 and Pas n 13 of Bahia, as well as Sor h 1, Sor h 2, Sor h 13 and Sor h 23 of Johnson grass, have been discovered. Research effort is directed towards making available subtropical grass pollen allergen components as innovative treatment and diagnostic options that more specifically address the needs of patients from warmer regions of the globe.
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33
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Roos M, Wang T, Shcherbakov AA, Hong M. Fast Magic-Angle-Spinning 19F Spin Exchange NMR for Determining Nanometer 19F- 19F Distances in Proteins and Pharmaceutical Compounds. J Phys Chem B 2018; 122:2900-2911. [PMID: 29486126 PMCID: PMC6312665 DOI: 10.1021/acs.jpcb.8b00310] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Internuclear distances measured using NMR provide crucial constraints of three-dimensional structures but are often restricted to about 5 Å due to the weakness of nuclear-spin dipolar couplings. For studying macromolecular assemblies in biology and materials science, distance constraints beyond 1 nm will be extremely valuable. Here we present an extensive and quantitative analysis of the feasibility of 19F spin exchange NMR for precise and robust measurements of interatomic distances up to 1.6 nm at a magnetic field of 14.1 T, under 20-40 kHz magic-angle spinning (MAS). The measured distances are comparable to those achievable from paramagnetic relaxation enhancement but have higher precision, which is better than ±1 Å for short distances and ±2 Å for long distances. For 19F spins with the same isotropic chemical shift but different anisotropic chemical shifts, intermediate MAS frequencies of 15-25 kHz without 1H irradiation accelerate spin exchange. For spectrally resolved 19F-19F spin exchange, 1H-19F dipolar recoupling significantly speeds up 19F-19F spin exchange. On the basis of data from five fluorinated synthetic, pharmaceutical, and biological compounds, we obtained two general curves for spin exchange between CF groups and between CF3 and CF groups. These curves allow 19F-19F distances to be extracted from the measured spin exchange rates after taking into account 19F chemical shifts. These results demonstrate the robustness of 19F spin exchange NMR for distance measurements in a wide range of biological and chemical systems.
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Affiliation(s)
- Matthias Roos
- Department of Chemistry , Massachusetts Institute of Technology , 170 Albany Street , Cambridge , Massachusetts 02139 , United States
| | - Tuo Wang
- Department of Chemistry , Massachusetts Institute of Technology , 170 Albany Street , Cambridge , Massachusetts 02139 , United States
| | - Alexander A Shcherbakov
- Department of Chemistry , Massachusetts Institute of Technology , 170 Albany Street , Cambridge , Massachusetts 02139 , United States
| | - Mei Hong
- Department of Chemistry , Massachusetts Institute of Technology , 170 Albany Street , Cambridge , Massachusetts 02139 , United States
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34
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Cosgrove DJ. Diffuse Growth of Plant Cell Walls. PLANT PHYSIOLOGY 2018; 176:16-27. [PMID: 29138349 PMCID: PMC5761826 DOI: 10.1104/pp.17.01541] [Citation(s) in RCA: 193] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 11/13/2017] [Indexed: 05/04/2023]
Abstract
Structural and functional roles of cellulose, xyloglucan, and pectins in cell wall enlargement are reappraised with insights from mechanics, atomic force microscopy, and other methods.
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Affiliation(s)
- Daniel J Cosgrove
- Department of Biology, Penn State University, University Park, Pennsylvania 16802
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35
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Phyo P, Wang T, Kiemle SN, O'Neill H, Pingali SV, Hong M, Cosgrove DJ. Gradients in Wall Mechanics and Polysaccharides along Growing Inflorescence Stems. PLANT PHYSIOLOGY 2017; 175:1593-1607. [PMID: 29084904 PMCID: PMC5717741 DOI: 10.1104/pp.17.01270] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 10/29/2017] [Indexed: 05/02/2023]
Abstract
At early stages of Arabidopsis (Arabidopsis thaliana) flowering, the inflorescence stem undergoes rapid growth, with elongation occurring predominantly in the apical ∼4 cm of the stem. We measured the spatial gradients for elongation rate, osmotic pressure, cell wall thickness, and wall mechanical compliances and coupled these macroscopic measurements with molecular-level characterization of the polysaccharide composition, mobility, hydration, and intermolecular interactions of the inflorescence cell wall using solid-state nuclear magnetic resonance spectroscopy and small-angle neutron scattering. Force-extension curves revealed a gradient, from high to low, in the plastic and elastic compliances of cell walls along the elongation zone, but plots of growth rate versus wall compliances were strikingly nonlinear. Neutron-scattering curves showed only subtle changes in wall structure, including a slight increase in cellulose microfibril alignment along the growing stem. In contrast, solid-state nuclear magnetic resonance spectra showed substantial decreases in pectin amount, esterification, branching, hydration, and mobility in an apical-to-basal pattern, while the cellulose content increased modestly. These results suggest that pectin structural changes are connected with increases in pectin-cellulose interaction and reductions in wall compliances along the apical-to-basal gradient in growth rate. These pectin structural changes may lessen the ability of the cell wall to undergo stress relaxation and irreversible expansion (e.g. induced by expansins), thus contributing to the growth kinematics of the growing stem.
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Affiliation(s)
- Pyae Phyo
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Tuo Wang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Sarah N Kiemle
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802
| | - Hugh O'Neill
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
| | - Sai Venkatesh Pingali
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Daniel J Cosgrove
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802
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36
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Affiliation(s)
- Daniel J. Cosgrove
- Department of Biology, Pennsylvania State University, University Park, Pennsylvania 16802
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37
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Gelenter MD, Wang T, Liao SY, O'Neill H, Hong M. 2H- 13C correlation solid-state NMR for investigating dynamics and water accessibilities of proteins and carbohydrates. JOURNAL OF BIOMOLECULAR NMR 2017; 68:257-270. [PMID: 28674916 PMCID: PMC6908442 DOI: 10.1007/s10858-017-0124-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 06/29/2017] [Indexed: 05/29/2023]
Abstract
Site-specific determination of molecular motion and water accessibility by indirect detection of 2H NMR spectra has advantages over dipolar-coupling based techniques due to the large quadrupolar couplings and the ensuing high angular resolution. Recently, a Rotor Echo Short Pulse IRrAdiaTION mediated cross polarization (RESPIRATIONCP) technique was developed, which allowed efficient transfer of 2H magnetization to 13C at moderate 2H radiofrequency field strengths available on most commercial MAS probes. In this work, we investigate the 2H-13C magnetization transfer characteristics of one-bond perdeuterated CD n spin systems and two-bond H/D exchanged C-(O)-D and C-(N)-D spin systems in carbohydrates and proteins. Our results show that multi-bond, broadband 2H-13C polarization transfer can be achieved using 2H radiofrequency fields of ~50 kHz, relatively short contact times of 1.3-1.7 ms, and with sufficiently high sensitivity to enable 2D 2H-13C correlation experiments with undistorted 2H spectra in the indirect dimension. To demonstrate the utility of this 2H-13C technique for studying molecular motion, we show 2H-13C correlation spectra of perdeuterated bacterial cellulose, whose surface glucan chains exhibit a motionally averaged C6 2H quadrupolar coupling that indicates fast trans-gauche isomerization about the C5-C6 bond. In comparison, the interior chains in the microfibril core are fully immobilized. Application of the 2H-13C correlation experiment to H/D exchanged Arabidopsis primary cell walls show that the O-D quadrupolar spectra of the highest polysaccharide peaks can be fit to a two-component model, in which 74% of the spectral intensity, assigned to cellulose, has a near-rigid-limit coupling, while 26% of the intensity, assigned to matrix polysaccharides, has a weakened coupling of 50 kHz. The latter O-D quadrupolar order parameter of 0.22 is significantly smaller than previously reported C-D dipolar order parameters of 0.46-0.55 for pectins, suggesting that additional motions exist at the C-O bonds in the wall polysaccharides. 2H-13C polarization transfer profiles are also compared between statistically deuterated and H/D exchanged GB1.
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Affiliation(s)
- Martin D Gelenter
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Tuo Wang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Shu-Yu Liao
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Hugh O'Neill
- Center for Structural Molecular Biology, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
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