46
FLUORESCENCE
Individual cell fluorescence spectra
Determination of the fluorescence properties of phytoplankton cells(excitation and emission
spectra) is possible using monochromatic dark field illumination (Campbell and Iturriaga,
1988). A special dark field condenser (e.g. Ultracondenser (Zeiss» and objectives with iris
diaphragms are required. A second monochromator placed before the photomultiplier is used
to scan or set the emission wavelength. Samples are prepared as described for absorption
measurements.
Fluorescence excitation spectra has been useful in discriminating between clones types of
picoplanktonic cells such as coccoid cyanobacteria (Synechococcus spp.) which can be
differentiated by their phycourobilin to phycoerythrobilin ratio (PUB:PEB). It has been found
that in the oligotrophic ocean and in most oceanic regions, the PUB-rich type predominate
(Fig. 4). In addition, this type of analysis has been useful for determining photoadaptive
states of individual planktonic microalgae.
ACKNOWLEDGEMENTS
The present research is supported by the Ocean Optics Program of the Office of Naval Research (contract
N00014-89-1047). The author thanks the NATO Advanced Study Institute on Individual Cell and Particle
Analysis in Oceanography Organizing Committee for their support.
REFERENCES
Iturriaga R, Mitchell BG, Kiefer DA (1988) Microphotometric analysis of individual particle
absorption spectra. Limnol Oceanogr 33: 128-135
Campbell L, Iturriaga R (1988) Identification of Synechococcus spp. in the Sargasso Sea by
immunofluorescence and fluorescence excitation spectroscopy performed on individual
cells. Limn01 Oceanogr 35: 1196-1201
Iturriaga R, Siegel D (1989) Microphotometric characterization of phytoplankton and detrital
absorption properties in the Sargasso Sea. Limnol Oceanogr 34: 1706-1726
FLUORESCENCE
Individual cell fluorescence spectra
Determination of the fluorescence properties of phytoplankton cells(excitation and emission
spectra) is possible using monochromatic dark field illumination (Campbell and Iturriaga,
1988). A special dark field condenser (e.g. Ultracondenser (Zeiss» and objectives with iris
diaphragms are required. A second monochromator placed before the photomultiplier is used
to scan or set the emission wavelength. Samples are prepared as described for absorption
measurements.
Fluorescence excitation spectra has been useful in discriminating between clones types of
picoplanktonic cells such as coccoid cyanobacteria (Synechococcus spp.) which can be
differentiated by their phycourobilin to phycoerythrobilin ratio (PUB:PEB). It has been found
that in the oligotrophic ocean and in most oceanic regions, the PUB-rich type predominate
(Fig. 4). In addition, this type of analysis has been useful for determining photoadaptive
states of individual planktonic microalgae.
ACKNOWLEDGEMENTS
The present research is supported by the Ocean Optics Program of the Office of Naval Research (contract
N00014-89-1047). The author thanks the NATO Advanced Study Institute on Individual Cell and Particle
Analysis in Oceanography Organizing Committee for their support.
REFERENCES
Iturriaga R, Mitchell BG, Kiefer DA (1988) Microphotometric analysis of individual particle
absorption spectra. Limnol Oceanogr 33: 128-135
Campbell L, Iturriaga R (1988) Identification of Synechococcus spp. in the Sargasso Sea by
immunofluorescence and fluorescence excitation spectroscopy performed on individual
cells. Limn01 Oceanogr 35: 1196-1201
Iturriaga R, Siegel D (1989) Microphotometric characterization of phytoplankton and detrital
absorption properties in the Sargasso Sea. Limnol Oceanogr 34: 1706-1726