Polymeric Gluten Proteins as Climate-Resilient Markers of Quality: Can LC-MS/MS Provide Valuable Information about Spring Wheat Grown in Diverse Climates?

In this study, the impact of the varying environments, wet-cool (2017), dry-hot (2018), and fluctuating (2019), on two spring wheat genotypes, Diskett and Bumble, grown in field conditions in southern Sweden was studied. From harvested grains, polymeric gluten proteins were fractionated and collected using SE-HPLC and then analyzed with LC-MS/MS. Proteins and peptides identified through searches against the protein sequences of (taxon 4565) from the UniProtKB database showed 7 high molecular weight glutenin subunits (HMW-GS) and 24 low molecular weight glutenin subunits (LMW-GS) with different enrichment levels for both genotypes. Glu-B1 for HMW-GS and Glu D3 and m- and s-types for LMW-GS were dominated in both genotypes, and a small proportion of α-, γ-, and ω-gliadins were also present. A minor variation in HMW-GS and LMW-GS compositions was observed between the years, while small amounts of heat shock proteins were identified under the "dry-hot" period for Diskett. In conclusion, Diskett showed more stable and climate-resistant protein patterns in the studied varying climate as compared to Bumble. The study highlights the use of proteomics and LC-MS/MS for differentiation of wheat genotypes, although it shows low sensitivity in measuring the diverse environment impact on the polymeric proteins.