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Xiao Y, Sun G, Yu Q, Gao T, Zhu Q, Wang R, Huang S, Han Z, Cervone F, Yin H, Qi T, Wang Y, Chai J. A plant mechanism of hijacking pathogen virulence factors to trigger innate immunity. Science 2024; 383:732-739. [PMID: 38359129 DOI: 10.1126/science.adj9529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 12/22/2023] [Indexed: 02/17/2024]
Abstract
Polygalacturonase-inhibiting proteins (PGIPs) interact with pathogen-derived polygalacturonases to inhibit their virulence-associated plant cell wall-degrading activity but stimulate immunity-inducing oligogalacturonide production. Here we show that interaction between Phaseolus vulgaris PGIP2 (PvPGIP2) and Fusarium phyllophilum polygalacturonase (FpPG) enhances substrate binding, resulting in inhibition of the enzyme activity of FpPG. This interaction promotes FpPG-catalyzed production of long-chain immunoactive oligogalacturonides, while diminishing immunosuppressive short oligogalacturonides. PvPGIP2 binding creates a substrate binding site on PvPGIP2-FpPG, forming a new polygalacturonase with boosted substrate binding activity and altered substrate preference. Structure-based engineering converts a putative PGIP that initially lacks FpPG-binding activity into an effective FpPG-interacting protein. These findings unveil a mechanism for plants to transform pathogen virulence activity into a defense trigger and provide proof of principle for engineering PGIPs with broader specificity.
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Affiliation(s)
- Yu Xiao
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Guangzheng Sun
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China
- Key Laboratory of Soybean Disease and Pest Control (Ministry of Agriculture and Rural Affairs), Nanjing Agricultural University, Nanjing 210095, China
- The Key Laboratory of Plant Immunity, Nanjing Agricultural University, Nanjing 210095, China
| | - Qiangsheng Yu
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Teng Gao
- Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qinsheng Zhu
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China
- Key Laboratory of Soybean Disease and Pest Control (Ministry of Agriculture and Rural Affairs), Nanjing Agricultural University, Nanjing 210095, China
- The Key Laboratory of Plant Immunity, Nanjing Agricultural University, Nanjing 210095, China
| | - Rui Wang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China
- Key Laboratory of Soybean Disease and Pest Control (Ministry of Agriculture and Rural Affairs), Nanjing Agricultural University, Nanjing 210095, China
- The Key Laboratory of Plant Immunity, Nanjing Agricultural University, Nanjing 210095, China
| | - Shijia Huang
- School of Life Sciences, Westlake University, Hangzhou 310024, China
| | - Zhifu Han
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou 310024, Zhejiang, China
| | - Felice Cervone
- Dipartimento di Biologia e Biotecnologie "C. Darwin," Sapienza, University of Rome, Piazzale Aldo Moro, 00185 Roma, Italy
| | - Heng Yin
- Dalian Engineering Research Center for Carbohydrate Agricultural Preparations, Liaoning Provincial Key Laboratory of Carbohydrates, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Tiancong Qi
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yuanchao Wang
- Department of Plant Pathology, Nanjing Agricultural University, Nanjing 210095, China
- Key Laboratory of Soybean Disease and Pest Control (Ministry of Agriculture and Rural Affairs), Nanjing Agricultural University, Nanjing 210095, China
- The Key Laboratory of Plant Immunity, Nanjing Agricultural University, Nanjing 210095, China
| | - Jijie Chai
- Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
- Beijing Frontier Research Center for Biological Structure, Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China
- School of Life Sciences, Westlake University, Hangzhou 310024, China
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou 310024, Zhejiang, China
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Safran J, Tabi W, Ung V, Lemaire A, Habrylo O, Bouckaert J, Rouffle M, Voxeur A, Pongrac P, Bassard S, Molinié R, Fontaine JX, Pilard S, Pau-Roblot C, Bonnin E, Larsen DS, Morel-Rouhier M, Girardet JM, Lefebvre V, Sénéchal F, Mercadante D, Pelloux J. Plant polygalacturonase structures specify enzyme dynamics and processivities to fine-tune cell wall pectins. THE PLANT CELL 2023; 35:3073-3091. [PMID: 37202370 PMCID: PMC10396364 DOI: 10.1093/plcell/koad134] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 04/11/2023] [Accepted: 05/10/2023] [Indexed: 05/20/2023]
Abstract
Polygalacturonases (PGs) fine-tune pectins to modulate cell wall chemistry and mechanics, impacting plant development. The large number of PGs encoded in plant genomes leads to questions on the diversity and specificity of distinct isozymes. Herein, we report the crystal structures of 2 Arabidopsis thaliana PGs, POLYGALACTURONASE LATERAL ROOT (PGLR), and ARABIDOPSIS DEHISCENCE ZONE POLYGALACTURONASE2 (ADPG2), which are coexpressed during root development. We first determined the amino acid variations and steric clashes that explain the absence of inhibition of the plant PGs by endogenous PG-inhibiting proteins (PGIPs). Although their beta helix folds are highly similar, PGLR and ADPG2 subsites in the substrate binding groove are occupied by divergent amino acids. By combining molecular dynamic simulations, analysis of enzyme kinetics, and hydrolysis products, we showed that these structural differences translated into distinct enzyme-substrate dynamics and enzyme processivities: ADPG2 showed greater substrate fluctuations with hydrolysis products, oligogalacturonides (OGs), with a degree of polymerization (DP) of ≤4, while the DP of OGs generated by PGLR was between 5 and 9. Using the Arabidopsis root as a developmental model, exogenous application of purified enzymes showed that the highly processive ADPG2 had major effects on both root cell elongation and cell adhesion. This work highlights the importance of PG processivity on pectin degradation regulating plant development.
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Affiliation(s)
- Josip Safran
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Wafae Tabi
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Vanessa Ung
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Adrien Lemaire
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Olivier Habrylo
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Julie Bouckaert
- UMR 8576 Unité de Glycobiologie Structurale et Fonctionnelle (UGSF), 50 Avenue de Halley, Villeneuve d’Ascq 59658, France
| | - Maxime Rouffle
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Aline Voxeur
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), Versailles 78000, France
| | - Paula Pongrac
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Solène Bassard
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Roland Molinié
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Jean-Xavier Fontaine
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Serge Pilard
- Plateforme Analytique, Université de Picardie, 33, Rue St Leu, Amiens 80039, France
| | - Corinne Pau-Roblot
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Estelle Bonnin
- INRAE, UR 1268 Biopolymers, Interactions Assemblies, CS 71627, Nantes Cedex 3 44316, France
| | - Danaé Sonja Larsen
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | | | | | - Valérie Lefebvre
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Fabien Sénéchal
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
| | - Davide Mercadante
- School of Chemical Sciences, The University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
| | - Jérôme Pelloux
- UMRT INRAE 1158 BioEcoAgro—BIOPI Biologie des Plantes et Innovation, Université de Picardie, 33 Rue St Leu, Amiens 80039, France
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Functional Classification and Characterization of the Fungal Glycoside Hydrolase 28 Protein Family. J Fungi (Basel) 2022; 8:jof8030217. [PMID: 35330219 PMCID: PMC8952511 DOI: 10.3390/jof8030217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 02/13/2022] [Accepted: 02/15/2022] [Indexed: 02/01/2023] Open
Abstract
Pectin is a major constituent of the plant cell wall, comprising compounds with important industrial applications such as homogalacturonan, rhamnogalacturonan and xylogalacturonan. A large array of enzymes is involved in the degradation of this amorphous substrate. The Glycoside Hydrolase 28 (GH28) family includes polygalacturonases (PG), rhamnogalacturonases (RG) and xylogalacturonases (XG) that share a structure of three to four pleated β-sheets that form a rod with the catalytic site amidst a long, narrow groove. Although these enzymes have been studied for many years, there has been no systematic analysis. We have collected a comprehensive set of GH28 encoding sequences to study their evolution in fungi, directed at obtaining a functional classification, as well as at the identification of substrate specificity as functional constraint. Computational tools such as Alphafold, Consurf and MEME were used to identify the subfamilies’ characteristics. A hierarchic classification defines the major classes of endoPG, endoRG and endoXG as well as three exoPG classes. Ascomycete endoPGs are further classified in two subclasses whereas we identify four exoRG subclasses. Diversification towards exomode is explained by loops that appear inserted in a number of turns. Substrate-driven diversification can be identified by various specificity determining positions that appear to surround the binding groove.
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Weikert T, Niehues A, Cord-Landwehr S, Hellmann MJ, Moerschbacher BM. Reassessment of chitosanase substrate specificities and classification. Nat Commun 2017; 8:1698. [PMID: 29167423 PMCID: PMC5700058 DOI: 10.1038/s41467-017-01667-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 10/05/2017] [Indexed: 01/09/2023] Open
Abstract
Chitosanases can be used to produce partially acetylated chitosan oligosaccharides (paCOS) for different applications, provided they are thoroughly characterized. However, recent studies indicate that the established classification system for chitosanases is too simplistic. Here, we apply a highly sensitive method for quantitatively sequencing paCOS to reassess the substrate specificities of the best-characterized class I–III chitosanases. The enzymes’ abilities to cleave bonds at GlcNAc residues positioned at subsite (−1) or (+1), on which the classification system is based, vary especially when the substrates have different fractions of acetylation (FA). Conflicts with the recent classification are observed at higher FA, which were not investigated in prior specificity determinations. Initial analyses of pectin-degrading enzymes reveal that classifications of other polysaccharide-degrading enzymes should also be critically reassessed. Based on our results, we tentatively suggest a chitosanase classification system which is based on specificities and preferences of subsites (−2) to (+2). Chitosanases are classified according to their specificity in cleaving bonds at GlcNAc residues but the current system may be too simplistic. Here, the authors use quantitative mass spectrometry to revisit chitosanase specificity and propose additional determinants for their classification.
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Affiliation(s)
- Tobias Weikert
- Institute for Biology and Biotechnology of Plants, University of Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Anna Niehues
- Institute for Biology and Biotechnology of Plants, University of Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Stefan Cord-Landwehr
- Institute for Biology and Biotechnology of Plants, University of Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Margareta J Hellmann
- Institute for Biology and Biotechnology of Plants, University of Münster, Schlossplatz 8, 48143, Münster, Germany
| | - Bruno M Moerschbacher
- Institute for Biology and Biotechnology of Plants, University of Münster, Schlossplatz 8, 48143, Münster, Germany.
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Pereira EO, Kolotilin I, Conley AJ, Menassa R. Production and characterization of in planta transiently produced polygalacturanase from Aspergillus niger and its fusions with hydrophobin or ELP tags. BMC Biotechnol 2014; 14:59. [PMID: 24970673 PMCID: PMC4083859 DOI: 10.1186/1472-6750-14-59] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 06/18/2014] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Pectinases play an important role in plant cell wall deconstruction and have potential in diverse industries such as food, wine, animal feed, textile, paper, fuel, and others. The demand for such enzymes is increasing exponentially, as are the efforts to improve their production and to implement their use in several industrial processes. The goal of this study was to examine the potential of producing polygalacturonase I from Aspergillus niger in plants and to investigate the effects of subcellular compartmentalization and protein fusions on its accumulation and activity. RESULTS Polygalacturonase I from Aspergillus niger (AnPGI) was transiently produced in Nicotiana benthamiana by targeting it to five different cellular compartments: apoplast, endoplasmic reticulum (ER), vacuole, chloroplast and cytosol. Accumulation levels of 2.5%, 3.0%, and 1.9% of total soluble protein (TSP) were observed in the apoplast, ER, and vacuole, respectively, and specific activity was significantly higher in vacuole-targeted AnPGI compared to the same enzyme targeted to the ER or apoplast. No accumulation was found for AnPGI when targeted to the chloroplast or cytosol. Analysis of AnPGI fused with elastin-like polypeptide (ELP) revealed a significant increase in the protein accumulation level, especially when targeted to the vacuole where the protein doubles its accumulation to 3.6% of TSP, while the hydrophobin (HFBI) fusion impaired AnPGI accumulation and both tags impaired activity, albeit to different extents. The recombinant protein showed activity against polygalacturonic acid with optimum conditions at pH 5.0 and temperature from 30 to 50°C, depending on its fusion. In vivo analysis of reducing sugar content revealed a higher release of reducing sugars in plant tissue expressing recombinant AnPGI compared to wild type N. benthamiana leaves. CONCLUSION Our results demonstrate that subcellular compartmentalization of enzymes has an impact on both the target protein accumulation and its activity, especially in the case of proteins that undergo post-translational modifications, and should be taken into consideration when protein production strategies are designed. Using plants to produce heterologous enzymes for the degradation of a key component of the plant cell wall could reduce the cost of biomass pretreatment for the production of cellulosic biofuels.
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Affiliation(s)
- Eridan Orlando Pereira
- Agriculture and Agri-Food Canada, 1391 Sandford Street, London, ON N5V 4T3, Canada
- Department of Biology, Western University, London, ON N6A 5B7, Canada
- Current address: Universidade Estadual do Ceará, Av. Dr. Silas Munguba, 1700 - Campus do Itaperi, Fortaleza 60714-903, Brazil
| | - Igor Kolotilin
- Agriculture and Agri-Food Canada, 1391 Sandford Street, London, ON N5V 4T3, Canada
| | | | - Rima Menassa
- Agriculture and Agri-Food Canada, 1391 Sandford Street, London, ON N5V 4T3, Canada
- Department of Biology, Western University, London, ON N6A 5B7, Canada
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Bonnin E, Garnier C, Ralet MC. Pectin-modifying enzymes and pectin-derived materials: applications and impacts. Appl Microbiol Biotechnol 2013; 98:519-32. [DOI: 10.1007/s00253-013-5388-6] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 11/05/2013] [Accepted: 11/05/2013] [Indexed: 11/30/2022]
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Rozeboom HJ, Beldman G, Schols HA, Dijkstra BW. Crystal structure of endo-xylogalacturonan hydrolase fromAspergillus tubingensis. FEBS J 2013; 280:6061-9. [DOI: 10.1111/febs.12524] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 09/10/2013] [Indexed: 11/26/2022]
Affiliation(s)
- Henriëtte J. Rozeboom
- Laboratory of Biophysical Chemistry; Groningen Biomolecular Sciences and Biotechnology Institute; University of Groningen; The Netherlands
| | - Gerrit Beldman
- Laboratory of Food Chemistry; Wageningen University; The Netherlands
| | - Henk A. Schols
- Laboratory of Food Chemistry; Wageningen University; The Netherlands
| | - Bauke W. Dijkstra
- Laboratory of Biophysical Chemistry; Groningen Biomolecular Sciences and Biotechnology Institute; University of Groningen; The Netherlands
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Gou JY, Miller LM, Hou G, Yu XH, Chen XY, Liu CJ. Acetylesterase-mediated deacetylation of pectin impairs cell elongation, pollen germination, and plant reproduction. THE PLANT CELL 2012; 24:50-65. [PMID: 22247250 PMCID: PMC3289554 DOI: 10.1105/tpc.111.092411] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Revised: 12/02/2011] [Accepted: 12/22/2011] [Indexed: 05/17/2023]
Abstract
Pectin is a major component of the primary cell wall of higher plants. Some galacturonyl residues in the backbone of pectinaceous polysaccharides are often O-acetylated at the C-2 or C-3 position, and the resulting acetylesters change dynamically during the growth and development of plants. The processes involve both enzymatic acetylation and deacetylation. Through genomic sequence analysis, we identified a pectin acetylesterase (PAE1) from black cottonwood (Populus trichocarpa). Recombinant Pt PAE1 exhibited preferential activity in releasing the acetate moiety from sugar beet (Beta vulgaris) and potato (Solanum tuberosum) pectin in vitro. Overexpressing Pt PAE1 in tobacco (Nicotiana tabacum) decreased the level of acetyl esters of pectin but not of xylan. Deacetylation engendered differential changes in the composition and/or structure of cell wall polysaccharides that subsequently impaired the cellular elongation of floral styles and filaments, the germination of pollen grains, and the growth of pollen tubes. Consequently, plants overexpressing PAE1 exhibited severe male sterility. Furthermore, in contrast to the conventional view, PAE1-mediated deacetylation substantially lowered the digestibility of pectin. Our data suggest that pectin acetylesterase functions as an important structural regulator in planta by modulating the precise status of pectin acetylation to affect the remodeling and physiochemical properties of the cell wall's polysaccharides, thereby affecting cell extensibility.
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Affiliation(s)
- Jin-Ying Gou
- Biology Department, Brookhaven National Laboratory, Upton, New York 11973
| | - Lisa M. Miller
- National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York 11973
| | - Guichuan Hou
- Appalachian State University, Boone, North Carolina 28608-2027
| | - Xiao-Hong Yu
- Biology Department, Brookhaven National Laboratory, Upton, New York 11973
| | - Xiao-Ya Chen
- National Key Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Shanghai 200032, China
| | - Chang-Jun Liu
- Biology Department, Brookhaven National Laboratory, Upton, New York 11973
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Massa C, Guarnaccia C, Lamba D, Anselmi C. Insight into the structure of an endopolygalacturonase from the phytopathogen Burkholderia cepacia: a biochemical and computational study. Biochimie 2010; 92:1445-53. [PMID: 20637827 DOI: 10.1016/j.biochi.2010.07.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Accepted: 07/07/2010] [Indexed: 11/30/2022]
Abstract
We have recently investigated and characterized the mode of action of BcPeh28A, an endopolygalacturonase (endoPG) from the phytopathogen Burkholderia cepacia. EndoPGs belong to glycoside hydrolase family 28 and are responsible for the hydrolysis of the non-esterified regions of pectins. Here we report a 3-D structural model of BcPeh28A by combining mass spectrometry (MS) analysis, aimed at disulphide bridges mapping, and computational modelling tools. MS analyses have revealed the complete pattern of disulphide bridges in BcPeh28A, pointing out the presence of three disulphide bonds, defined as Cys3-25, Cys216-244 and Cys309-421. A 3-D model of BcPeh28A was generated by computational methods based on profile-profile sequence alignments and fold recognition algorithms. The final model exhibits a right-handed β-helix fold with eleven β-helical coils and includes the disulphide bonds as additional spatial restraints. Molecular dynamics simulations have been performed to test the conformational stability of the model. Finally, the structural analysis of the BcPeh28A model allows defining the architecture and the amino acid topology of the subsites involved in the catalysis and in the substrate binding specificity.
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Affiliation(s)
- Claudia Massa
- Structural Biology Laboratory, Sincrotrone Trieste S.C.p.A., AREA Science Park - Basovizza Strada Statale 14, km 163,5, I-34149 Trieste, Italy.
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