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Shewry P. Wheat grain proteins: Past, present, and future. Cereal Chem 2023; 100:9-22. [PMID: 37064052 PMCID: PMC10087814 DOI: 10.1002/cche.10585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 07/13/2022] [Accepted: 07/14/2022] [Indexed: 11/06/2022]
Abstract
Background and Objectives Research on wheat grain proteins is reviewed, including achievements over the past century and priorities for future research. The focus is on three groups of proteins that have major impacts on wheat quality and utilization: the gluten proteins which determine dough viscoelasticity but also trigger celiac disease in susceptible individuals, the puroindolines which are major determinants of grain texture and the amylase/trypsin inhibitors which are food and respiratory allergens and are implicated in triggering celiac disease and nonceliac wheat sensitivity. Findings Although earlier work focused on protein structure and properties, the development of genomics and high-sensitivity proteomics has resulted in the availability of a vast amount of information on the amino acid sequences of individual wheat proteins, including allelic variants of gluten proteins which are associated with good processing quality and of puroindolines, which are associated with a hard or soft grain texture, and on protein expression and polymorphism. Conclusions However, our ability to exploit this knowledge is limited by a lack of detailed understanding of the structure:function relationships of wheat proteins. In particular, we need to understand how the three-dimensional structures of the individual proteins determine their interactions with other grain components (to determine functional properties) and with the immune systems of susceptible consumers (to trigger adverse responses), how these interactions are affected by allelic variation, and how they can be manipulated. Significance and Novelty The article, therefore, identifies priorities for future research which should enable the adoption of a more rational approach to improving the quality of wheat grain proteins.
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Three Diverse Granule Preparation Methods for Proteomic Analysis of Mature Rice (Oryza sativa L.) Starch Grain. Molecules 2022; 27:molecules27103307. [PMID: 35630784 PMCID: PMC9144640 DOI: 10.3390/molecules27103307] [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: 12/19/2021] [Revised: 05/09/2022] [Accepted: 05/19/2022] [Indexed: 02/01/2023] Open
Abstract
Starch is the primary form of reserve carbohydrate storage in plants. Rice (Oryza sativa L.) is a monocot whose reserve starch is organized into compounded structures within the amyloplast, rather than a simple starch grain (SG). The mechanism governing the assembly of the compound SG from polyhedral granules in apposition, however, remains unknown. To further characterize the proteome associated with these compounded structures, three distinct methods of starch granule preparation (dispersion, microsieve, and flotation) were performed. Phase separation of peptides (aqueous trypsin-shaving and isopropanol solubilization of residual peptides) isolated starch granule-associated proteins (SGAPs) from the distal proteome of the amyloplast and the proximal ‘amylome’ (the amyloplastic proteome), respectively. The term ‘distal proteome’ refers to SGAPs loosely tethered to the amyloplast, ones that can be rapidly proteolyzed, while proximal SGAPs are those found closer to the remnant amyloplast membrane fragments, perhaps embedded therein—ones that need isopropanol solvent to be removed from the mature organelle surface. These two rice starch-associated peptide samples were analyzed using nano-liquid chromatography–tandem mass spectrometry (Nano-HPLC-MS/MS). Known and novel proteins, as well as septum-like structure (SLS) proteins, in the mature rice SG were found. Data mining and gene ontology software were used to categorize these putative plastoskeletal components as a variety of structural elements, including actins, tubulins, tubulin-like proteins, and cementitious elements such as reticulata related-like (RER) proteins, tegument proteins, and lectins. Delineating the plastoskeletal proteome begins by understanding how each starch granule isolation procedure affects observed cytoplasmic and plastid proteins. The three methods described herein show how the technique used to isolate SGs differentially impacts the subsequent proteomic analysis and results obtained. It can thus be concluded that future investigations must make judicious decisions regarding the methodology used in extracting proteomic information from the compound starch granules being assessed, since different methods are shown to yield contrasting results herein. Data are available via ProteomeXchange with identifier PXD032314.
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Ji X, Li X, Wu S, Hou M, Zhao Y. Effects of graphene oxide on algal cellular stress response: Evaluating metabolic characters of carbon fixation and nutrient removal. CHEMOSPHERE 2020; 252:126566. [PMID: 32222521 DOI: 10.1016/j.chemosphere.2020.126566] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 03/10/2020] [Accepted: 03/18/2020] [Indexed: 06/10/2023]
Abstract
The effects of different concentrations of graphene oxide (GO) on intracellular metabolism in Chlorella vulgaris (C. vulgaris) and removal of nitrogen and phosphorus nutrients by C. vulgaris from synthetic wastewater were studied. The results demonstrated that cell division of Chlorella vulgaris increased at 24 h and decreased at 96 h after exposure to different concentrations of GO. The removal rates of total nitrogen (TN), ammoniacal nitrogen (NH3-N), phosphate (PO43--P), and chemical oxygen demand (COD) were 24.1%, 70.0%, 37.0%, and 39.6%, respectively, when the concentration of GO was 0.01 mg/L 10 mg/L GO induced severe plasmolysis and cytoplasmic contraction. Furthermore, the protein-like exopolysaccharide (EPS) content of algal cells exposed to 10 mg/L GO decrease to 10.8% of the control group. Simultaneously, the reactive oxygen species (ROS) level was 175.4% of control group. The biological responses to 10 mg/L GO included increase in ROS level, inhibition of saccharide metabolism, and degradation of amino acids. In addition, high concentrations of 10 mg/L GO weakened the carbon fixation process in algal cells. These stress-response behaviors increased cell permeability and oxidative stress. Overall, these findings provide new insights regarding the effects of GO on algal cellular stress responses.
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Affiliation(s)
- Xiyan Ji
- School of Ecological Technology and Engineering, Shanghai Institute of Technology, Shanghai, 201418, PR China
| | - Xin Li
- School of Ecological Technology and Engineering, Shanghai Institute of Technology, Shanghai, 201418, PR China
| | - Shichao Wu
- School of Ecological Technology and Engineering, Shanghai Institute of Technology, Shanghai, 201418, PR China
| | - Meifang Hou
- School of Ecological Technology and Engineering, Shanghai Institute of Technology, Shanghai, 201418, PR China.
| | - Yongjun Zhao
- School of Ecological Technology and Engineering, Shanghai Institute of Technology, Shanghai, 201418, PR China.
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Shabrangy A, Roustan V, Reipert S, Weidinger M, Roustan PJ, Stoger E, Weckwerth W, Ibl V. Using RT-qPCR, Proteomics, and Microscopy to Unravel the Spatio-Temporal Expression and Subcellular Localization of Hordoindolines Across Development in Barley Endosperm. FRONTIERS IN PLANT SCIENCE 2018; 9:775. [PMID: 29951075 PMCID: PMC6008550 DOI: 10.3389/fpls.2018.00775] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Accepted: 05/22/2018] [Indexed: 05/20/2023]
Abstract
Hordeum vulgare (barley) hordoindolines (HINs), HINa, HINb1, and HINb2, are orthologous proteins of wheat puroindolines (PINs) that are small, basic, cysteine-rich seed-specific proteins and responsible for grain hardness. Grain hardness is, next to its protein content, a major quality trait. In barley, HINb is most highly expressed in the mid-stage developed endosperm and is associated with both major endosperm texture and grain hardness. However, data required to understand the spatio-temporal dynamics of HIN transcripts and HIN protein regulation during grain filling processes are missing. Using reverse transcription quantitative PCR (RT-qPCR) and proteomics, we analyzed HIN transcript and HIN protein abundance from whole seeds (WSs) at four [6 days after pollination (dap), 10, 12, and ≥20 dap] as well as from aleurone, subaleurone, and starchy endosperm at two (12 and ≥20 dap) developmental stages. At the WS level, results from RT-qPCR, proteomics, and western blot showed a continuous increase of HIN transcript and HIN protein abundance across these four developmental stages. Miroscopic studies revealed HIN localization mainly at the vacuolar membrane in the aleurone, at protein bodies (PBs) in subaleurone and at the periphery of starch granules in the starchy endosperm. Laser microdissetion (LMD) proteomic analyses identified HINb2 as the most prominent HIN protein in starchy endosperm at ≥20 dap. Additionally, our quantification data revealed a poor correlation between transcript and protein levels of HINs in subaleurone during development. Here, we correlated data achieved by RT-qPCR, proteomics, and microscopy that reveal different expression and localization pattern of HINs in each layer during barley endosperm development. This indicates a contribution of each tissue to the regulation of HINs during grain filling. The effect of the high protein abundance of HINs in the starchy endosperm and their localization at the periphery of starch granules at late development stages at the cereal-based end-product quality is discussed. Understanding the spatio-temporal regulated HINs is essential to improve barley quality traits for high end-product quality, as hard texture of the barley grain is regulated by the ratio between HINb/HINa.
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Affiliation(s)
- Azita Shabrangy
- Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria
| | - Valentin Roustan
- Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria
| | - Siegfried Reipert
- Core Facility Cell Imaging and Ultrastructure Research, University of Vienna, Vienna, Austria
| | - Marieluise Weidinger
- Core Facility Cell Imaging and Ultrastructure Research, University of Vienna, Vienna, Austria
| | - Pierre-Jean Roustan
- Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria
| | - Eva Stoger
- Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Wolfram Weckwerth
- Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria
- Vienna Metabolomics Center, University of Vienna, Vienna, Austria
| | - Verena Ibl
- Department of Ecogenomics and Systems Biology, University of Vienna, Vienna, Austria
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Quayson ET, Marti A, Morris CF, Marengo M, Bonomi F, Seetharaman K, Iametti S. Structural consequences of the interaction of puroindolines with gluten proteins. Food Chem 2018; 253:255-261. [PMID: 29502829 DOI: 10.1016/j.foodchem.2018.01.146] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 10/30/2017] [Accepted: 01/23/2018] [Indexed: 11/26/2022]
Abstract
The effect of puroindolines (PINs) on structural characteristics of wheat proteins was investigated in Triticum turgidum ssp. durum (cv. Svevo) and Triticum aestivum (cv. Alpowa) and in their respective derivatives in which PIN genes were expressed (Soft Svevo) or the distal end of the short arm of chromosome 5D was deleted and PINs were not expressed (Hard Alpowa). The presence of PINs decreased the amount of cold-SDS extractable proteins and the accessibility of protein thiols to specific reagents, but resulted in facilitated solvation of gluten proteins, as detected by tryptophan fluorescence measurements carried out on minimally mixed flour/water mixtures. We propose that PINs and gluten proteins are interacting in the grain or flour prior to mixing. Hydrophobic interactions between PINs and some of the gluten proteins modify the pattern of interactions among gluten proteins, thus providing an additional mechanistic rationale for the effects of PINs on kernel hardness.
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Affiliation(s)
- Enoch T Quayson
- Department of Food Science and Nutrition, University of Minnesota, 1334 Eckles Ave., St. Paul, MN 55108, USA; Department of Biochemistry, Science Building, University of Cape Coast, Cape Coast, Ghana
| | - Alessandra Marti
- Department of Food Science and Nutrition, University of Minnesota, 1334 Eckles Ave., St. Paul, MN 55108, USA; Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, via G. Celoria 2, 20133 Milan, Italy.
| | - Craig F Morris
- USDA-ARS Western Wheat Quality Laboratory, Washington State University, E-202 Food Science & Human Nutrition Facility East, Pullman, WA 99164, USA
| | - Mauro Marengo
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, via G. Celoria 2, 20133 Milan, Italy
| | - Francesco Bonomi
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, via G. Celoria 2, 20133 Milan, Italy
| | - Koushik Seetharaman
- Department of Food Science and Nutrition, University of Minnesota, 1334 Eckles Ave., St. Paul, MN 55108, USA
| | - Stefania Iametti
- Department of Food, Environmental and Nutritional Sciences, Università degli Studi di Milano, via G. Celoria 2, 20133 Milan, Italy
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Wheat puroindolines tether to starch granule surfaces in puroindoline-null (Pin-null) plants. J Cereal Sci 2018. [DOI: 10.1016/j.jcs.2017.06.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Kumar R, Arora S, Singh K, Garg M. Puroindoline allelic diversity in Indian wheat germplasm and identification of new allelic variants. BREEDING SCIENCE 2015; 65:319-26. [PMID: 26366114 PMCID: PMC4542932 DOI: 10.1270/jsbbs.65.319] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 06/20/2015] [Indexed: 05/13/2023]
Abstract
Grain hardness is an important quality trait that influences product development in wheat. This trait is governed by variation in puroindoline proteins (PINA and PINB). Our study evaluated 551 Indian wheat germplasm lines for diversity in Pina and Pinb genes. Eighty-two lines were shortlisted for full length sequencing and grain hardness studies. Sequencing studies identified six unknown alleles: two for the Pina gene and four for the Pinb gene. Five of them were novel with non-synonymous changes in the corresponding amino acid sequences. Identified mutations in the deduced mature proteins and their pre- and pro-peptides influenced the hardness characteristics of the grain. We classified these 82 varieties into different hardness categories with reference to international and Indian systems of classification. The majority of Indian wheat varieties were categorized as hard. This study revealed that unexplored Indian wheat germplasm can be a good source of genetic variability for both Pina and Pinb genes, helping in marker-assisted breeding and in obtaining wheat with different textural properties.
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Affiliation(s)
- Rohit Kumar
- National Agri-Food Biotechnology Institute,
Mohali-160071, Punjab,
India
| | - Shaweta Arora
- National Agri-Food Biotechnology Institute,
Mohali-160071, Punjab,
India
| | - Kashmir Singh
- Department of Biotechnology, Panjab University,
Chandigarh-160014,
India
| | - Monika Garg
- National Agri-Food Biotechnology Institute,
Mohali-160071, Punjab,
India
- Corresponding author (e-mail: )
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Alfred RL, Palombo EA, Panozzo JF, Bhave M. The co-operative interaction of puroindolines in wheat grain texture may involve the hydrophobic domain. J Cereal Sci 2014. [DOI: 10.1016/j.jcs.2014.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Pauly A, Pareyt B, Fierens E, Delcour JA. Wheat (Triticum aestivum L. and T. turgidum L. ssp. durum) Kernel Hardness: I. Current View on the Role of Puroindolines and Polar Lipids. Compr Rev Food Sci Food Saf 2013; 12:413-426. [PMID: 33412687 DOI: 10.1111/1541-4337.12019] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 04/08/2013] [Indexed: 12/30/2022]
Abstract
Wheat hardness has major consequences for the entire wheat supply chain from breeders and millers over manufacturers to, finally, consumers of wheat-based products. Indeed, differences in hardness among Triticum aestivum L. or between T. aestivum L. and T. turgidum L. ssp. durum wheat cultivars determine not only their milling properties, but also the properties of flour or semolina endosperm particles, their preferential use in cereal-based applications, and the quality of the latter. Although the mechanism causing differences in wheat hardness has been subject of research more than once, it is still not completely understood. It is widely accepted that differences in wheat hardness originate from differences in the interaction between the starch granules and the endosperm protein matrix in the kernel. This interaction seems impacted by the presence of either puroindoline a and/or b, polar lipids on the starch granule surface, or by a combination of both. We focus here on wheat hardness and its relation to the presence of puroindolines and polar lipids. More in particular, the structure, properties, and genetics of puroindolines and their interactions with polar lipids are critically discussed as is their possible role in wheat hardness. We also address future research needs as well as the presence of puroindoline-type proteins in other cereals.
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Affiliation(s)
- Anneleen Pauly
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
| | - Bram Pareyt
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
| | - Ellen Fierens
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
| | - Jan A Delcour
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), KU Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium
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Obukhova LV, Efremova TT, Shumny VK. Characterization of puroindolines in the control of endosperm texture in common wheat lines with substitutions of homeologous group-5 chromosomes. RUSS J GENET+ 2013. [DOI: 10.1134/s1022795412120071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Ramalingam A, Palombo EA, Bhave M. The Pinb-2 genes in wheat comprise a multigene family with great sequence diversity and important variants. J Cereal Sci 2012. [DOI: 10.1016/j.jcs.2012.02.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Kim KH, Feiz L, Martin J, Giroux M. Puroindolines are associated with decreased polar lipid breakdown during wheat seed development. J Cereal Sci 2012. [DOI: 10.1016/j.jcs.2012.02.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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13
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The starch granule associated proteomes of commercially purified starch reference materials from rice and maize. J Proteomics 2012; 75:993-1003. [DOI: 10.1016/j.jprot.2011.10.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 10/17/2011] [Accepted: 10/21/2011] [Indexed: 11/24/2022]
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14
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Mottiar Y, Altosaar I. Iodine sequestration by amylose to combat iodine deficiency disorders. Trends Food Sci Technol 2011. [DOI: 10.1016/j.tifs.2011.02.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Zhang J, Martin JM, Beecher B, Lu C, Hannah LC, Wall ML, Altosaar I, Giroux MJ. The ectopic expression of the wheat Puroindoline genes increase germ size and seed oil content in transgenic corn. PLANT MOLECULAR BIOLOGY 2010; 74:353-65. [PMID: 20725765 PMCID: PMC4165627 DOI: 10.1007/s11103-010-9679-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2009] [Accepted: 08/10/2010] [Indexed: 05/04/2023]
Abstract
Plant oil content and composition improvement is a major goal of plant breeding and biotechnology. The Puroindoline a and b (PINA and PINB) proteins together control whether wheat seeds are soft or hard textured and share a similar structure to that of plant non-specific lipid-transfer proteins. Here we transformed corn (Zea mays L.) with the wheat (Triticum aestivum L.) puroindoline genes (Pina and Pinb) to assess their effects upon seed oil content and quality. Pina and Pinb coding sequences were introduced into corn under the control of a corn Ubiquitin promoter. Three Pina/Pinb expression positive transgenic events were evaluated over two growing seasons. The results showed that Pin expression increased germ size significantly without negatively impacting seed size. Germ yield increased 33.8% while total seed oil content was increased by 25.23%. Seed oil content increases were primarily the result of increased germ size. This work indicates that higher oil content corn hybrids having increased food or feed value could be produced via puroindoline expression.
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Affiliation(s)
- Jinrui Zhang
- Department of Plant Sciences and Plant Pathology, Montana State University, 119 Plant Bioscience Building, Bozeman, MT 59717-3150, USA.
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Wall ML, Wheeler HL, Smith J, Figeys D, Altosaar I. Mass spectrometric analysis reveals remnants of host-pathogen molecular interactions at the starch granule surface in wheat endosperm. PHYTOPATHOLOGY 2010; 100:848-854. [PMID: 20701481 DOI: 10.1094/phyto-100-9-0848] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The starch granules of wheat seed are solar energy-driven deposits of fixed carbon and, as such, present themselves as targets of pathogen attack. The seed's array of antimicrobial proteins, peptides, and small molecules comprises a molecular defense against penetrating pathogens. In turn, pathogens exhibit an arsenal of enzymes to facilitate the degradation of the host's endosperm. In this context, the starch granule surface is a relatively unexplored domain in which unique molecular barriers may be deployed to defend against and inhibit the late stages of infection. Therefore, it was compelling to explore the starch granule surface in mature wheat seed, which revealed evidence of host-pathogen molecular interactions that may have occurred during grain development. In this study, starch granules from the soft wheat Triticum aestivum cv. AC Andrew and hard wheat T. turgidum durum were isolated and water washed 20 times, and their surface proteins were digested in situ with trypsin. The peptides liberated into the supernatant and the peptides remaining at the starch granule surface were separately examined. In this way, we demonstrated that the identified proteins have a strong affinity for the starch granule surface. Proteins with known antimicrobial activity were identified, as well as several proteins from the plant pathogens Agrobacterium tumefaciens, Pectobacterium carotovorum, Fusarium graminearum, Magnaporthe grisea, Xanthomonas axonopodis, and X. oryzae. Although most of these peptides corresponded to uncharacterized hypothetical proteins of fungal pathogens, several peptide fragments were identical to cytosolic and membrane proteins of specific microbial pathogens. During development and maturation, wheat seed appeared to have resisted infection and lysed the pathogens where, upon desiccation, the molecular evidence remained fixed at the starch granule surface.
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Affiliation(s)
- Michael L Wall
- Department of Biochemistry , Microbiology and Immunology, University of Ottawa, Ottawa, Canada
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