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Nagesh CR, Prashat G R, Goswami S, Bharadwaj C, Praveen S, Ramesh SV, Vinutha T. Sulfate transport and metabolism: strategies to improve the seed protein quality. Mol Biol Rep 2024; 51:242. [PMID: 38300326 DOI: 10.1007/s11033-023-09166-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 12/15/2023] [Indexed: 02/02/2024]
Abstract
Sulfur-containing amino acids (SAA), namely methionine, and cysteine are crucial essential amino acids (EAA) considering the dietary requirements of humans and animals. However, a few crop plants, especially legumes, are characterized with suboptimal levels of these EAA thereby limiting their nutritive value. Hence, improved comprehension of the mechanistic perspective of sulfur transport and assimilation into storage reserve, seed storage protein (SSP), is imperative. Efforts to augment the level of SAA in seed storage protein form an integral component of strategies to balance nutritive quality and quantity. In this review, we highlight the emerging trends in the sulfur biofortification approaches namely transgenics, genetic and molecular breeding, and proteomic rebalancing with sulfur nutrition. The transgenic 'push and pull strategy' could enhance sulfur capture and storage by expressing genes that function as efficient transporters, sulfate assimilatory enzymes, sulfur-rich foreign protein sinks, or by suppressing catabolic enzymes. Modern molecular breeding approaches that adopt high throughput screening strategies and machine learning algorithms are invaluable in identifying candidate genes and alleles associated with SAA content and developing improved crop varieties. Sulfur is an essential plant nutrient and its optimal uptake is crucial for seed sulfur metabolism, thereby affecting seed quality and yields through proteomic rebalance between sulfur-rich and sulfur-poor seed storage proteins.
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Affiliation(s)
- C R Nagesh
- Division of Biochemistry, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Rama Prashat G
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Suneha Goswami
- Division of Biochemistry, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - C Bharadwaj
- Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Shelly Praveen
- Division of Biochemistry, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - S V Ramesh
- ICAR-Central Plantation Crops Research Institute, 671 124, Kasaragod, Kerala, India.
| | - T Vinutha
- Division of Biochemistry, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
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Zheng H, Yan G, Lee Y, Alcaraz C, Marquez S, de Mejia EG. Effect of the extrusion process on allergen reduction and the texture change of soybean protein isolate-corn and soybean flour-corn mixtures. INNOV FOOD SCI EMERG 2020. [DOI: 10.1016/j.ifset.2020.102421] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Kim WS, Krishnan HB. Impact of co-expression of maize 11 and 18 kDa δ-zeins and 27 kDa γ-zein in transgenic soybeans on protein body structure and sulfur amino acid content. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 280:340-347. [PMID: 30824013 DOI: 10.1016/j.plantsci.2018.12.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 12/11/2018] [Accepted: 12/13/2018] [Indexed: 05/27/2023]
Abstract
The methionine-rich seed storage proteins of maize have been expressed in transgenic plants as a means to improve the overall sulfur amino acid content of seed. Previous attempts to increase the sulfur amino acid content of soybean seeds by this approach has met with limited success. It has been shown co-expression of different class of zeins can result in their stable accumulation in transgenic plants. In this study, conventional crosses between transgenic plants individually expressing 11, 18 kDa δ-zeins and 27 kDa γ-zein were made to obtain plants that simultaneously express both the δ-zein and γ-zein. Transmission electron microscopic observation of thin-sections of transgenic soybean seeds revealed that the zeins accumulated in ER-derived protein bodies (PBs) which were found sparsely scattered in cytoplasm. The size of these PBs varied from 0.2 to 0.6 μm in soybean plants individually expressing 11, 18 kDa δ-zeins and 27 kDa γ-zein. In contrast, soybeans co-expressing the 18 kDa δ-zein and 27 kDa γ-zein the PBs was 3-4 times larger. Electron microscopic observation also revealed the sequestration of PBs inside the vacuoles where they could be subjected to degradation by vacuolar proteases. Amino acid analysis of transgenic soybean individually expressing 11, 18 kDa δ-zeins and 27 kDa γ-zein revealed only a minimal increase in the overall methionine content compared to the wild-type. In contrast, plants co-expressing 18 kDa δ-zein and 27 kDa γ-zein showed a significant increase (27%) in the methionine content compared to the control seeds.
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Affiliation(s)
- Won-Seok Kim
- Plant Science Division, University of Missouri, Columbia, MO 65211, United States
| | - Hari B Krishnan
- Plant Science Division, University of Missouri, Columbia, MO 65211, United States; Plant Genetics Research, USDA-Agricultural Research Service, Columbia, MO 65211, United States.
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de Santis B, Stockhofe N, Wal JM, Weesendorp E, Lallès JP, van Dijk J, Kok E, De Giacomo M, Einspanier R, Onori R, Brera C, Bikker P, van der Meulen J, Kleter G. Case studies on genetically modified organisms (GMOs): Potential risk scenarios and associated health indicators. Food Chem Toxicol 2018; 117:36-65. [DOI: 10.1016/j.fct.2017.08.033] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/03/2017] [Accepted: 08/22/2017] [Indexed: 01/07/2023]
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Alqahtani MS, Islam MS, Podaralla S, Kaushik RS, Reineke J, Woyengo T, Perumal O. Food Protein Based Core–Shell Nanocarriers for Oral Drug Delivery: Effect of Shell Composition on in Vitro and in Vivo Functional Performance of Zein Nanocarriers. Mol Pharm 2017; 14:757-769. [DOI: 10.1021/acs.molpharmaceut.6b01017] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Mohammed S. Alqahtani
- Department
of Pharmaceutical Sciences, ∥Department of Biology and Microbiology/Veterinary
and Biomedical Sciences, and ⊥Department of Animal Science, South Dakota State University, Brookings, South Dakota 57007, United States
| | - M. Saiful Islam
- Department
of Pharmaceutical Sciences, ∥Department of Biology and Microbiology/Veterinary
and Biomedical Sciences, and ⊥Department of Animal Science, South Dakota State University, Brookings, South Dakota 57007, United States
| | - Satheesh Podaralla
- Department
of Pharmaceutical Sciences, ∥Department of Biology and Microbiology/Veterinary
and Biomedical Sciences, and ⊥Department of Animal Science, South Dakota State University, Brookings, South Dakota 57007, United States
| | - Radhey S. Kaushik
- Department
of Pharmaceutical Sciences, ∥Department of Biology and Microbiology/Veterinary
and Biomedical Sciences, and ⊥Department of Animal Science, South Dakota State University, Brookings, South Dakota 57007, United States
| | - Joshua Reineke
- Department
of Pharmaceutical Sciences, ∥Department of Biology and Microbiology/Veterinary
and Biomedical Sciences, and ⊥Department of Animal Science, South Dakota State University, Brookings, South Dakota 57007, United States
| | - Tofuko Woyengo
- Department
of Pharmaceutical Sciences, ∥Department of Biology and Microbiology/Veterinary
and Biomedical Sciences, and ⊥Department of Animal Science, South Dakota State University, Brookings, South Dakota 57007, United States
| | - Omathanu Perumal
- Department
of Pharmaceutical Sciences, ∥Department of Biology and Microbiology/Veterinary
and Biomedical Sciences, and ⊥Department of Animal Science, South Dakota State University, Brookings, South Dakota 57007, United States
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Zhang Y, Cui L, Li F, Shi N, Li C, Yu X, Chen Y, Kong W. Design, fabrication and biomedical applications of zein-based nano/micro-carrier systems. Int J Pharm 2016; 513:191-210. [DOI: 10.1016/j.ijpharm.2016.09.023] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/05/2016] [Accepted: 09/07/2016] [Indexed: 12/13/2022]
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Zhang Y, Cui L, Che X, Zhang H, Shi N, Li C, Chen Y, Kong W. Zein-based films and their usage for controlled delivery: Origin, classes and current landscape. J Control Release 2015; 206:206-19. [DOI: 10.1016/j.jconrel.2015.03.030] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 03/24/2015] [Accepted: 03/25/2015] [Indexed: 12/11/2022]
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Pandurangan S, Sandercock M, Beyaert R, Conn KL, Hou A, Marsolais F. Differential response to sulfur nutrition of two common bean genotypes differing in storage protein composition. FRONTIERS IN PLANT SCIENCE 2015; 6:92. [PMID: 25750649 PMCID: PMC4335288 DOI: 10.3389/fpls.2015.00092] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 02/04/2015] [Indexed: 05/28/2023]
Abstract
It has been hypothesized that the relatively low concentration of sulfur amino acids in legume seeds might be an ecological adaptation to nutrient poor, marginal soils. SARC1 and SMARC1N-PN1 are genetically related lines of common bean (dry bean, Phaseolus vulgaris) differing in seed storage protein composition. In SMARC1N-PN1, the lack of phaseolin and major lectins is compensated by increased levels of sulfur-rich proteins, resulting in an enhanced concentration of cysteine and methionine, mostly at the expense of the abundant non-protein amino acid, S-methylcysteine. To identify potential effects associated with an increased concentration of sulfur amino acids in the protein pool, the response of the two genotypes to low and high sulfur nutrition was evaluated under controlled conditions. Seed yield was increased by the high sulfate treatment in SMARC1N-PN1. The seed concentrations of sulfur, sulfate, and S-methylcysteine were altered by the sulfur treatment in both genotypes. The concentration of total cysteine and extractible globulins was increased specifically in SMARC1N-PN1. Proteomic analysis identified arcelin-like protein 4, lipoxygenase-3, albumin-2, and alpha amylase inhibitor beta chain as having increased levels under high sulfur conditions. Lipoxygenase-3 accumulation was sensitive to sulfur nutrition only in SMARC1N-PN1. Under field conditions, both SARC1 and SMARC1N-PN1 exhibited a slight increase in yield in response to sulfur treatment, typical for common bean.
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Affiliation(s)
- Sudhakar Pandurangan
- Department of Biology, University of Western OntarioLondon, ON, Canada
- Genomics and Biotechnology, Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Mark Sandercock
- Cereal Research Centre Morden, Agriculture and Agri-Food CanadaCanada, Morden, MB, Canada
| | - Ronald Beyaert
- Genomics and Biotechnology, Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Kenneth L. Conn
- Genomics and Biotechnology, Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, ON, Canada
| | - Anfu Hou
- Cereal Research Centre Morden, Agriculture and Agri-Food CanadaCanada, Morden, MB, Canada
| | - Frédéric Marsolais
- Department of Biology, University of Western OntarioLondon, ON, Canada
- Genomics and Biotechnology, Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, ON, Canada
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Zhang Y, Schernthaner J, Labbé N, Hefford MA, Zhao J, Simmonds DH. Improved protein quality in transgenic soybean expressing a de novo synthetic protein, MB-16. Transgenic Res 2014; 23:455-67. [PMID: 24435987 DOI: 10.1007/s11248-013-9777-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 12/16/2013] [Indexed: 11/28/2022]
Abstract
To improve soybean [Glycine max (L.) Merrill] seed nutritional quality, a synthetic gene, MB-16 was introduced into the soybean genome to boost seed methionine content. MB-16, an 11 kDa de novo protein enriched in the essential amino acids (EAAs) methionine, threonine, lysine and leucine, was originally developed for expression in rumen bacteria. For efficient seed expression, constructs were designed using the soybean codon bias, with and without the KDEL ER retention sequence, and β-conglycinin or cruciferin seed specific protein storage promoters. Homozygous lines, with single locus integrations, were identified for several transgenic events. Transgene transmission and MB-16 protein expression were confirmed to the T5 and T7 generations, respectively. Quantitative RT-PCR analysis of developing seed showed that the transcript peaked in growing seed, 5-6 mm long, remained at this peak level to the full-sized green seed and then was significantly reduced in maturing yellow seed. Transformed events carrying constructs with the rumen bacteria codon preference showed the same transcription pattern as those with the soybean codon preference, but the transcript levels were lower at each developmental stage. MB-16 protein levels, as determined by immunoblots, were highest in full-sized green seed but the protein virtually disappeared in mature seed. However, amino acid analysis of mature seed, in the best transgenic line, showed a significant increase of 16.2 and 65.9 % in methionine and cysteine, respectively, as compared to the parent. This indicates that MB-16 elevated the sulfur amino acids, improved the EAA seed profile and confirms that a de novo synthetic gene can enhance the nutritional quality of soybean.
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Affiliation(s)
- Yunfang Zhang
- Eastern Cereals and Oilseed Research Centre, Agriculture and Agri-Food Canada, Ottawa, ON, K1A0C6, Canada
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Șuteu D, Băcilă I, Haș V, Haș I, Miclăuș M. Romanian maize (Zea mays) inbred lines as a source of genetic diversity in SE Europe, and their potential in future breeding efforts. PLoS One 2014; 8:e85501. [PMID: 24392016 PMCID: PMC3877385 DOI: 10.1371/journal.pone.0085501] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Accepted: 11/27/2013] [Indexed: 11/24/2022] Open
Abstract
Maize has always been under constant human selection ever since it had been domesticated. Intensive breeding programs that resulted in the massive use of hybrids nowadays have started in the 60s. That brought significant yield increases but reduced the genetic diversity at the same time. Consequently, breeders and researchers alike turned their attention to national germplasm collections established decades ago in many countries, as they may hold allelic variations that could prove useful for future improvements. These collections are mainly composed of inbred lines originating from well-adapted local open pollinated varieties. However, there is an overall lack of data in the literature about the genetic diversity of maize in SE Europe, and its potential for future breeding efforts. There are no data, whatsoever, on the nutritional quality of the grain, primarily dictated by the zein proteins. We therefore sought to use the Romanian maize germplasm as an entry point in understanding the molecular make-up of maize in this part of Europe. By using 80 SSR markers, evenly spread throughout the genome, on 82 inbred lines from various parts of the country, we were able to decipher population structure and the existing relationships between those and the eight international standards used, including the reference sequenced genome B73. Corroborating molecular data with a standardized morphological, physiological, and biochemical characterization of all 90 inbred lines, this is the first comprehensive such study on the existing SE European maize germplasm. The inbred lines we present here are an important addition to the ever-shrinking gene pool that the breeding programs are faced-with, because of the allelic richness they hold. They may serve as parental lines in crosses that will lead to new hybrids, characterized by a high level of heterosis, nationwide and beyond, due to their existing relationship with the international germplasm.
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Affiliation(s)
- Dana Șuteu
- National Institute of Research and Development for Biological Sciences, Cluj-Napoca, Romania
| | - Ioan Băcilă
- National Institute of Research and Development for Biological Sciences, Cluj-Napoca, Romania
| | - Voichița Haș
- Agricultural Research and Development Station, Turda, Romania
| | - Ioan Haș
- Agricultural Research and Development Station, Turda, Romania
- University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca, Romania
| | - Mihai Miclăuș
- National Institute of Research and Development for Biological Sciences, Cluj-Napoca, Romania
- * E-mail:
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Abstract
Protein bodies are natural structures containing protein aggregates that exist in many organisms ranging from bacteria to mammals and plants. In bacteria they are often a phenomenon associated to over-expression of heterologous proteins. In mammals the so called Russell bodies indicate an accumulation of mutated immune globulins. In plants the protein bodies play a major role as protein storage organelle in seeds. Besides these natural cases, protein bodies can also be artificially induced primarily using self-assembling peptides. Frequently plant derived proteins such as prolamins or their derivatives are used. In some cases the help of an endoplasmatic retention signal is needed to create artificial protein bodies. The biotechnological application of protein bodies offers novel solutions such as the simplification of downstream processing in protein manufacture, the utilisation as particle for immunisation as vaccines or as carrier free self immobilised enzyme particle for many industrial catalytic processes.
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Krishnan HB, Chen MH. Identification of an abundant 56 kDa protein implicated in food allergy as granule-bound starch synthase. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:5404-5409. [PMID: 23675783 DOI: 10.1021/jf4014372] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Rice, the staple food of south and east Asian counties, is considered to be hypoallergenic. However, several clinical studies have documented rice-induced allergy in sensitive patients. Rice proteins with molecular weights of 14-16, 26, 33, and 56 kDa have been identified as allergens. Recently, it was documented that the 56 kDa rice allergen was responsible for rice-induced anaphylaxis. The 14-16 kDa allergens have been identified as α-amylase inhibitors; the 26 kDa protein has been identified as α-globulin; and the 33 kDa protein has been identified as glyoxalase I. However, the identity of the 56 kDa rice allergen has not yet been determined. In this study, we demonstrate that serum from patients allergic to maize shows IgE binding to a 56 kDa protein that was present in both maize and rice but not in the oil seeds soybean and peanut. The 56 kDa IgE-binding protein was abundant in the rice endosperm. We have purified this protein from rice endosperm and demonstrated its reactivity to IgE antibodies from the serum of maize-allergic patients. The purified protein was subjected to matrix-assisted laser desorption ionization-time of flight-tandem mass spectrometry analysis, resulting in identification of this rice allergen as granule-bound starch synthase, a product of the Waxy gene. Immunoblot analysis using protein extracts from a waxy mutant of rice revealed the absence of the 56 kDa IgE-binding protein. Our results demonstrate that the 56 kDa rice allergen is granule-bound starch synthase and raise the possibility of using waxy mutants of rice as a potential source of the hypoallergenic diet for patients sensitized to the 56 kDa rice allergen.
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Affiliation(s)
- Hari B Krishnan
- Plant Genetics Research Unit, Agricultural Research Service (ARS), United States Department of Agriculture (USDA), University of Missouri , Columbia, Missouri 65211, United States
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Fonseca C, Planchon S, Renaut J, Oliveira MM, Batista R. Characterization of maize allergens — MON810 vs. its non-transgenic counterpart. J Proteomics 2012; 75:2027-37. [DOI: 10.1016/j.jprot.2012.01.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 12/29/2011] [Accepted: 01/04/2012] [Indexed: 01/23/2023]
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Cabrera-Chávez F, Iametti S, Miriani M, de la Barca AMC, Mamone G, Bonomi F. Maize prolamins resistant to peptic-tryptic digestion maintain immune-recognition by IgA from some celiac disease patients. PLANT FOODS FOR HUMAN NUTRITION (DORDRECHT, NETHERLANDS) 2012; 67:24-30. [PMID: 22298027 DOI: 10.1007/s11130-012-0274-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Maize is used as an alternative to wheat to elaborate food stuffs for celiac patients in a gluten-free diet.However, some maize prolamins (zeins) contain amino acid sequences that resemble the wheat gluten immunodominant peptides and their integrity after gastrointestinal proteolysisis unknown. In this study, the celiac IgA-immunoreactivity to zeins from raw or nixtamalized grains, before and after peptic/tryptic digestion was evaluated and their possible immunogenicity was investigated by in silico methods.IgA from some celiac patients with HLA-DQ2 or DQ8 haplotypes recognized two alpha-zeins even after peptic/ tryptic proteolysis. However, digestion affected zeins after denaturation, reduction, and alkylation, used for identification of prolamins as alpha-zein A20 and A30 by MS/MS sequencing. An in silico analysis indicated that other zeins contain similar sequences, or sequences that may bind even better to the HLA-DQ2/DQ8 molecules compared to the already identified ones. Results concur to indicate that relative abundance of these zeins, along with factors affecting their resistance to proteolysis, may be of paramount clinical relevance, and the use of maize in the formulation and preparation of gluten-free foods must be reevaluated in some cases of celiac disease.
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Affiliation(s)
- Francisco Cabrera-Chávez
- Dipartimento di Scienze Molecolari Agroalimentari, Università degli Studi di Milano, Milano, Italy
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Krishnan HB, Jang S, Kim WS, Kerley MS, Oliver MJ, Trick HN. Biofortification of soybean meal: immunological properties of the 27 kDa γ-zein. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:1223-8. [PMID: 21226519 DOI: 10.1021/jf103613s] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Legumes, including soybeans ( Glycine max ), are deficient in sulfur-containing amino acids, which are required for the optimal growth of monogastric animals. This deficiency can be overcome by expressing heterologous proteins rich in sulfur-containing amino acids in soybean seeds. A maize 27 kDa γ-zein, a cysteine-rich protein, has been successfully expressed in several crops including soybean, barley, and alfalfa with the intent to biofortify these crops for animal feed. Previous work has shown that the maize 27 kDa zein can withstand digestion by pepsin and elicit an immunogenic response in young pigs. By use of sera from patients who tested positive by ImmunoCAP assay for elevated IgE to maize proteins, specific IgE binding to the 27 kDa γ-zein is demonstrated. Bioinformatic analysis using the full-length and 80 amino acid sliding window FASTA searches identified significant sequence homology of the 27 kDa γ-zein with several known allergens. Immunoblot analysis using human serum that cross-reacts with maize seed proteins also revealed specific IgE-binding to the 27 kDa γ-zein in soybean seed protein extracts containing the 27 kDa zein. This study demonstrates for the first time the allergenicity potential of the 27 kDa γ-zein and the potential that this protein has to limit livestock performance when used in soybeans that serve as a biofortified feed supplement.
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Affiliation(s)
- Hari B Krishnan
- Plant Genetics Research Unit, Agricultural Research Service, U.S. Department of Agriculture , Columbia, Missouri 65211, United States.
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