Characterization of gluten proteins by proteoform profiling to better understand gluten form and function
| dc.contributor.author | Bacala, Ray | |
| dc.contributor.examiningcommittee | McKenna, Sean (Chemistry) | |
| dc.contributor.examiningcommittee | O'Neil, Joe (Chemistry) | |
| dc.contributor.examiningcommittee | Krokhin, Oleg (Internal Medicine) | |
| dc.contributor.examiningcommittee | Guzman, Carlos Garcia (Genetics Escuela Técnica Superior de Ingeniería Agronómica y de Montes) | |
| dc.contributor.guestmembers | Hatcher, Dave (Canadian Grain Commission) | |
| dc.contributor.supervisor | Perreault, Héléne | |
| dc.contributor.supervisor | Fu, Bin Xiao | |
| dc.date.accessioned | 2024-01-09T21:30:34Z | |
| dc.date.available | 2024-01-09T21:30:34Z | |
| dc.date.issued | 2024-01-04 | |
| dc.date.submitted | 2024-01-04T17:11:09Z | en_US |
| dc.degree.discipline | Chemistry | en_US |
| dc.degree.level | Doctor of Philosophy (Ph.D.) | |
| dc.description.abstract | Gluten proteins have the unique property of forming gluten, a viscoelastic protein polymer, upon hydration and mixing. This makes the resulting dough uniquely suited to a wide variety of baked goods (e.g. bread, cookies and cakes) and pasta. Gluten composition therefore defines the functionality of a flour. Relating gluten composition to functional physical properties has been challenged by the inability to characterize the intact polymer due to its size and the incredible complexity of the wheat genome. The overall objective of this work was to develop new methods of measuring gluten protein components in order to better understand compositional changes and their effect on physical dough properties. To this end, a proteoform profiling method was developed that resolved intact proteins chromatographically and by mass with ± 2 Da (standard deviation) mass accuracy. Retention time and instrument sensitivity corrections were developed, redering data acquired on different days comparable. Two previously uncharacterized protein modifications were detected through the analysis of a population of two parent wheat and 28 progeny lines. A population of 20+ pairs of proteins that differed by 163 Da was detected. One pair was purified and identified as a low-molecular weight glutenin, differing by the loss of a conserved C-terminal tyrosine. Previously, this modification had only been observed in mammalian α-tubulin. High-molecular weight glutenin mass variants were also observed, differing by the loss of a C-terminal hexapeptide after a conserved aspartate. Whether or not these modifications directly affect gluten functionality, they may be markers for differences in the timing of cellular events during seed maturation and therefore indicate functional changes. This proteoform profiling approach can be applied to quantitatively compare gluten protein composition in a wide variety of samples to detect novel protein modifications and use a “big data” approach to correlating composition to functional quality. Any new understanding of the biochemical basis of wheat functionality can provide new tools to breeders to continue adapting wheat varieties to meet global demands. | |
| dc.description.note | February 2024 | |
| dc.description.sponsorship | Canadian Grain Commission | |
| dc.identifier.uri | http://hdl.handle.net/1993/37964 | |
| dc.language.iso | eng | |
| dc.rights | open access | en_US |
| dc.subject | Wheat | |
| dc.subject | gluten | |
| dc.subject | proteomics | |
| dc.subject | functional quality | |
| dc.title | Characterization of gluten proteins by proteoform profiling to better understand gluten form and function | |
| dc.type | doctoral thesis | en_US |
| local.subject.manitoba | no |