IMMUNO-FLOW CYTOMETRIC IDENTIFICATION AND ENUMERATION OF THE ICHTHYOTOXIC DINOFLAGELLATE GYRODINIUM-AUREOLUM HULBURT IN ARTIFICIALLY MIXED ALGAL POPULATIONS
Eg. Vrieling et al., IMMUNO-FLOW CYTOMETRIC IDENTIFICATION AND ENUMERATION OF THE ICHTHYOTOXIC DINOFLAGELLATE GYRODINIUM-AUREOLUM HULBURT IN ARTIFICIALLY MIXED ALGAL POPULATIONS, Journal of plankton research, 18(8), 1996, pp. 1503-1512
Flow cytometric identification and enumeration of Gyrodinium aureolum
Hulburt (Dinophyceae) were performed in artificially mixed algal popul
ations using direct immunofluorescence. Calibration of the flow cytome
ter, performed with a mixed algal population spiked with immunofluores
cently labelled G.aureolum cells, showed that selection of target cell
s after analysis on green and orange fluorescence can be done with a r
ecovery of 91.8% [coefficient of variation (CV) = 0.09]. Other selecti
on methods were less good, with 67.4% (CV = 0.16) and 58.4% (CV = 0.43
) recovery based on green and red fluorescence or green fluorescence a
nd perpendicular light scattering. For mixed algal populations spiked
with unlabelled G.aureolum cells, the quantification of target cells w
as quite good (recovery of 76.7%; CV = 0.20). The percentage of total
cell loss was high (58.0-92.0%), but this was caused mostly by loss of
species smaller in size than G. aureolum. Estimates of the relative c
ontribution of C. altreoblum in labelled samples were therefore often
far too high, but detection and quantification were not affected. The
methodological underestimation (23.3%) was partly caused by gating on
green and orange fluorescence (inaccuracy 8.2%).