Effects of concanavalin a on pattern formation inHydrodictyaceae

Summary The effect of concanavalin A upon colony formation inPediastrum boryanum andHydrodictyon reticulatum was tested. Cell aggregation and the development of the pattern specific cell shape are influenced in both species; moreover, inPediastrum the lectin causes preservation of the swarming vesicle which normally persists only a short time after the zoospores have settled. With addition of horseradish peroxidase or application of fluoresceinconjugated concanavalin A binding of the lectin to the cell surface can be demonstrated. The existence of discrete adhesive sites on the zoospore surface which might be responsible for cell-cell recognition is being discussed.