Evaluation of the Major Seed Storage Proteins, the Conglutins, Across Genetically Diverse Narrow-Leafed Lupin Varieties

Abstract

Lupin seeds have an excellent nutritional profile, including a high proportion of protein and dietary fiber. These qualities make lupin seeds an ideal candidate to help meet the growing global demand for complementary sources of protein. Of consequence to this application, there are nutritional and antinutritional properties assigned to the major lupin seed storage proteins—referred to as α-, β-, δ- and γ-conglutins The variation in the abundance of these protein families can impact the nutritional and bioactive properties of different lupin varieties. Hence, exploring the conglutin protein profiles across a diverse range of lupin varieties will yield knowledge that can facilitate the selection of superior genotypes for food applications or lupin crop improvement. To support this knowledge generation, discovery proteomics was applied for the identification of the 16 known conglutin subfamilies from 46 domestic and wild narrow-leafed lupin (NLL) genotypes. Consequently, the diversity of abundance of these proteins was evaluated using liquid chromatography–multiple reaction monitoring-mass spectrometry (LC–MRM-MS). This comparative study revealed a larger variability for the β- and δ-conglutin content across the lines under study. The absence/lower abundance of the β2- to β6-conglutin subfamilies in a subset of the domesticated cultivars led to substantially lower overall levels of the allergenic β-conglutin content in these NLLs, for which the elevation of the other conglutin families were observed. The diversity of the conglutin profiles revealed through this study—and the identification of potential hypoallergenic genotypes—will have great significance for lupin allergic consumers, food manufactures as well as grain breeders through the future development of lupin varieties with higher levels of desirable bioactive proteins and lower allergen content.

Influence of Roasting Temperature on the Detectability of Potentially Allergenic Lupin by SDS-PAGE, ELISAs, LC-MS/MS, and Real-Time PCR

“…Protein extracts obtained with extraction protocol 2 were subjected to LC-MS/MS. The found and selected peptides were mainly in accordance with other studies [ 31 , 51 ]. The mentioned circumstances and difficulties to find unique peptides for δ-conglutins were already described by Tahmasian et al [ 51 ].…”

“…The found and selected peptides were mainly in accordance with other studies [ 31 , 51 ]. The mentioned circumstances and difficulties to find unique peptides for δ-conglutins were already described by Tahmasian et al [ 51 ]. Similar outcomes were presented by a study of Downs et al, 2016, who used LFQ to examine heat impact and extraction efficiency for detection of allergens from roasted walnuts [ 52 ].…”

Comparative Seed Proteome Profile Reveals No Alternation of Major Allergens in High-Yielding Mung Bean Cultivars

“…albumins and nonlipid transfer proteins), pathogenesis-related proteins (PR-proteins), oleosins, defensins, and storage proteins (globulins and seed-specific albumins), have high sequence homology and exhibit IgE binding activities, 23,24 the discovery of additional allergen proteins in understudied legumes, such as mung beans, is expected. Qualitative and quantitative alternations of allergen proteins in response to cultivars have been well documented in many crops, 25−28 including legumes such as peanut, 29 soybean, 30−35 common bean, 36 lentil, 37 lupin, 37,38 and pea. 39 Thus, it is important to thoroughly assess the allergen profile of any newly developed cultivar.…”

“…IgE cross-reactivity of these proteins has also been confirmed by immunoblot analysis. , Recently, some other mung bean proteins, including convicilin, vicilin, and β-conglycinin, have also shown evidence of possible allergenicity. , Because most legume allergens, including profilins (2S albumins and nonlipid transfer proteins), pathogenesis-related proteins (PR-proteins), oleosins, defensins, and storage proteins (globulins and seed-specific albumins), have high sequence homology and exhibit IgE binding activities, , the discovery of additional allergen proteins in understudied legumes, such as mung beans, is expected. Qualitative and quantitative alternations of allergen proteins in response to cultivars have been well documented in many crops, − including legumes such as peanut, soybean, − common bean, lentil, lupin, , and pea . Thus, it is important to thoroughly assess the allergen profile of any newly developed cultivar.…”

Functional Association between Storage Protein Mobilization and Redox Signaling in Narrow-Leafed Lupin (Lupinus angustifolius L.) Seed Germination and Seedling Development

“…These studies collectively suggest that conglutins and other storage proteins may interface with redox signaling pathways, contributing to the orchestration of seed germination and early seedling development [42][43][44]. Furthermore, Tahmasian et al illuminated the nutritional aspects of lupin seeds in their recent investigation from 2022, highlighting NLL conglutins as a source of essential amino acids and bioactive compounds [45]. Together, this body of literature underscores the multifaceted role of conglutins in lupin seed biology and provides a foundation for our investigation into the functional association between storage protein mobilization and redox signaling in Lupinus angustifolius L. seed germination and seedling development [42][43][44][45].…”