Poulton, N. J.. Woods Hole Oceanographic Institution, npoulton@whoi.edu
Anderson, D. J.. Woods Hole Oceanographic Institution, danderson@whoi.edu

 
SPECIES-SPECIFIC ISOLATION AND PHYSIOLOGICAL CHARACTERIZATION OF THE DINOFLAGELLATE ALEXANDRIUM FUNDYENSE SEPARATED FROM FIELD SAMPLES USING IMMUNOMAGNETIC BEADS
 
An improved method for isolating live cells of the toxic dinoflagellate Alexandrium fundyense from field populations was developed using immunomagnetic bead separation. By isolating taxon-specific cells from mixed assemblages in-situ, physiological changes at the species level can be examined. Two magnetic bead approaches were tested: a direct method, in which a cell-specific antibody is attached to a paramagnetic bead and this complex binds to the target Alexandrium cell, and an indirect method, in which the antibody is attached to the target cell and paramagnetic beads are added to form a cell/bead complex. A 15ml tube magnetic particle separator was used for cell isolation in both approaches. Using 2.8Ám M-280 paramagnetic beads, the 'indirect' bead-to-cell attachment scheme was applied to mixed field assemblages that contained Alexandrium cells. The method was optimized for field samples by increasing the sample volume used for separation and by modifying wash solutions and paramagnetic bead concentrations. Optimal recovery of Alexandrium was approximately 60% from a variety of plankton samples. Isolated cells have been frozen for physiological measurements -currently in progress- of total protein, CHN and total carbohydrate. The results of these measurements and an evaluation of the strengths and weaknesses of the method will be discussed.
 
Day: Tuesday, Feb. 2
Time: 02:15 - 02:30pm
Location: Sweeney Center
 
Code: SS41TU0215S