A Simple Fluorescent Labeling Technique for the Marking of Algae in Mixed Assemblages

ABSTRACT

The fluorescent protein stain 5-(4, 6-dichlorotriazin-2-yl) aminofluorescein (DTAF) has been used to mark bacteria in grazing studies. I modified and simplified the procedure for use with algae. A mixed assemblage of algal genera (Oscillatoria, Ulothrix, Selenastrum, Ankistrodesmus, and Synedra) was exposed to die stain for 20 hours in the dark at room temperature. Stained cells appeared apple-green in color when observed with a UV microscope, and were distinguishable from each other and from a mixture of unstained algae. While there was some difficulty with solubility, it appears that DTAF can be adapted for use with algal cells.