ABSTRACT
Objective@#To establish a labeling method for bacterial outer membrane vesicle (OMV) based on luciferase reporting gene. @*Methods@#By utilizing the characteristics that high abundance of outer membrane protein A (OmpA) presented on the surface of bacterial OMV, the outer membrane protein-luciferase fusion protein was constructed to position the luciferase on the surface of the outer membrane vesicle, and the number of bacterial OMV was evaluated based on the luciferase activity. @*Results@#The OmpA-NanoLuc fusion protein expression vector was constructed successfully, and the outer membrane vesicles secreted by the subject strains after the expression of the fusion protein displayed stable luciferase activity. The number of bacterial outer membrane vesicles was semi-quantitative detrmined by measuring the activity of fluorescein enzyme. @*Conclusion@#A semi-quantitative method based on luciferase labeling was developed for the detection of extracellular vesicles, which could be used to evaluate the secretion level of specific strains.