HIRSCHMUGL, CAROL1*, MARIA BUNTA1, JUSTIN HOLT1, MARIO GIORDANO2, ANDREJ SKILIROV3, and J. RUDI STRICKLER4. 1University of Wisconsin-Milwaukee, Department of Physics, Milwaukee, WI 53211; 2Institute of Marine Sciences, Faculty of Sciences, University of Ancona, Via Brecce Bianche, 60131 Ancona, Italy; 3University of Wisconsin-Milwaukee, Advanced Analysis Facility, Milwaukee, WI 53211,; 4University of Wisconsin-Milwaukee, WATER Institute, Milwaukee, WI 53211. - Synchrotron-based infrared imaging of Euglena gracilis single cells.
Infrared (IR) Microspectroscopy is used to examine and identify the
chemistry in individual living cells of Euglena gracilis. The
spectra provide relative concentrations of lipids, proteins and
carbohydrates in the specimen. Diffraction-limited, spatially-resolved
IR images of single cells of the microalga were measured using
synchrotron radiation as a bright IR source. These contour maps reveal
the distributions of the proteins, lipids and carbohydrates including
the phospholipids, sugars and paramylon. We compare the images with
the biochemistry for Euglena gracilis. We also present the IR
images for two different cells, which were exposed to different
culture conditions prior to the measurements. The overall trends
observed for the two specimens are in qualitative agreement with the
hypothesis that there was a significantly reduced concentration of
nitrogen in the culture as a function of time. Importantly, this study
demonstrates the potential to examine changes in the chemistry of
living cells while modifying environmental stimuli.
Key words: cell composition, FTIR, macromolecular pools, microspectroscopy, synchrotron radiation