Location: Methods and Application of Food Composition Laboratory
Project Number: 8040-10700-004-002-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2020
End Date: Aug 31, 2025
Objective:
1. Analyze raw and processed commodity foods to obtain a comprehensive glycomic and glycoproteomic maps of the foods.
2. Obtain and compare the glycomic and proteomic variations among different varieties of raw foods (e.g. rice, potato, corn, legumes, fruits).
3. Determine the effects of processing methods on glycomic and proteomic maps of foods (e.g. various forms of corn such as flour, tortilla, corn syrup, cornbread, or boiled corn).
4. Relate glycomic and proteomic maps to source of food (e.g. farm, field management procedures, harvesting, climate, soil).
5. Examine effects of different carbohydrate foods on the gut microbiome and
glycoproteomic profiles in intestinal/immune tissues.
Approach:
Foods in different forms will be analyzed with the most advanced glycomic and glycoproteomic profiling tools. The analysis involves comprehensive glycomic and proteomic profiling employing advanced separations methods including nanoflow and microflow liquid chromatography and a host of mass spectrometry platforms including quadrupole time of flight (QTOF), triple quadrupole (QQQ), and Fourier transform mass spectrometry (FTMS-orbitrap).
Glycomic platform:
Carbohydrates analysis will be performed to determine the free monosaccharides, disaccharides, oligosaccharides, and polysaccharide compositions of the foods. To determine free monosaccharides and disaccharides, the compounds will be tagged with a mass sensitive label to enhance ionization allowing liquid-chromatography – mass spectrometry (LC-MS) analysis. Free oligosaccharides will be analyzed directly, with purification, by LC-MS to obtain the profile of the various polymeric species. Polysaccharide analysis will be performed using an oxidative method for degrading polymers that yield glycan signatures that are used to identify the parent polysaccharide.
Proteomic platform:
Proteomic analysis of foods will be performed to identify the protein and the glycan posttranslational modifications of proteins. This method will obtain the specific proteins through standard proteomic methods and the unique proteins that make up each food. The analysis will be performed using trypsin to digest the proteins and LC-MS to identify the peptides using software and methods in a proteomic workflow. Additionally, the glycosylation of the proteins will be determined to provide the glycomic composition of the proteins.
Glycoproteomic analyses will be performed on samples (diet, feces, intestinal
mucin,etc) obtained in experiments designed to examine the impact of specific
diets with different carbohydrate structures (e.g. resistant starch) on the
microbiome and GI function/immunity.
