Lectin-based detection of Escherichia coli and Staphylococcus aureus by flow cytometry

This study develops a flow cytometry analysis of the bacterial pathogens Escherichia coli and Staphylococcus aureus based on a ligand–bioreceptor interaction. We used fluorescently labeled plant lectins as natural receptors that could specifically interact with the cell wall carbohydrates of bacteria. An epifluorescence microscopy was used as an additional approach to confirm and visualize lectin–carbohydrate interactions. The binding specificity of plant lectins to E. coli and S. aureus cells was studied, and wheat germ agglutinin, which provided high-affinity interactions, was selected as a receptor. Using this method, bacterial pathogens can be detected in concentrations of up to 106 cells/mL within 5 min. Their accessibility and universality make lectin reagents a promising tool to control a wide range of bacterial pathogens.