Lectin binding assay reveals phytoplasma infection-induced alteration of plant host protein glycosylation

Glycosylation is a common posttranslational modification that contributes to the activity and stability of diverse eukaryotic proteins. The present study performed a lectin binding assay using four biotinylated lectins and investigated changes in protein glycosylation patterns in tomato plants infected with potato purple top (PPT) phytoplasma. The results revealed that in PPT phytoplasma-infected tomato plants there was an increase in the levels of protein glycosylation involving mannose, galactose, and N-galactosamine glycans, while those of fucose glycans were decreased. Confocal microscopy analysis indicated that the altered glycosylation activities occurred mainly in the phloem tissue of infected plants. These findings suggest that PPT phytoplasma infection can significantly impact the glycosylation patterns of tomato plant proteins, which could provide valuable insights into the mechanisms of plant response to phytoplasma infection and potential strategies for crop protection.