Relationship between metabolic activities and optical densities investigated in yeast cells using the microscopic techniques of SEM, LPM, and SNOM
Dressler, C.1, Beuthan, J.1, Minet, O.1,2, Motzkus, R.2, Hirst, L.2, Balanos, E.3, Graschew, G.3, Müller, G.1,2
1Institut für Medizinische/Technische Physik und Lasermedizin, Freie Universität Berlin, Krahmerstr. 6-10, D-12207 Berlin; 2Laser-Medizin-Technologie Berlin gGmbH; 3OP2000, Robert-Rössle-Klinik
Scanning electron microscopy (SEM) is a well established technique whereas laser phase microscopy (LPM) and scanning near-field optical microscopy (SNOM) are newer techniques. The value of same for application in the biomedical sciences must first be subjected to critical approval. The computer-aided LPM is based on the conversion of laser-induced interferometric dynamics into electric signals restored as 3D profiles. The SNOM technique uses a nanoscopic probe as an optical emitter/detector for scanning the specimen in a maximum dynamic distance of 4µm. All three devices have a spatial resolution in the nm-range. The influence of metabolic activities on the intracellular patterns of optical densities and their correlation with cellular geometries were investigated in yeast Saccharomyces cerevisiae as a simple cell model. When resting cells were compared with budding cells, different phase distributions were observed. Resting cells exhibited nucleus and membrane correlated phase delays while in budding cells more diffuse patterns of higher phase intensities were detected. The phase intensity relations between the mother cell and the descendents depended on the developmental state of the budding process as well as the number of buds per cell. These observations suggested that the phase intensities and intensity patterns of individual cells are modified by their metabolic activities.
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| LOCATION |
DATE |
TIME |
| Lecture Hall II |
Sunday, April 5 |
02:20 pm |