Sweet potato has a complex genome and an even more complex chemical composition, with low protein content in the roots (the part that people eat) and many secondary metabolites in the leaves, making it difficult to extract sufficient quantities of proteins for analysis.
The researchers extracted proteins from sweet potato root and leaf samples and cut them into peptides, which they analyzed using liquid chromatography and mass spectrometry. They identified 3,143 unique proteins from sweet potato leaves and 2,928 from the roots. When they compared the proteomic data with the genome of the sweet potato, the researchers identified some regions in the published genome sequence where their data could provide enhanced information. For example, the analysis predicted 741 new protein-coding regions that previously were not thought to be genes. The group says the results could be used to help further characterize and biofortify the tuber.
For more details, read the news release from the American Chemical Society.