Decho, A. W. University of South Carolina, adecho@sph.sc.edu

 
NEW APPROACHES IN THE CHEMICAL CHARACTERIZATION OF NATURAL MICROBIAL EXTRACELLULAR POLYMERS
 
Microbial extracellular polymers (EPS) serve a range of roles in marine processes. A determinative parameter in understanding their roles lies in characterizing physical/chemical properties of natural EPS. LaboratoryEPS can be produced and studied. However, caution must be exercised in extrapolating physical/chemical properties of "LabEPS"to those of natural environments. Techniques are currently being employed to analyze both natural and laboratory EPS from marine cyanobacteria. The techniques provide distinct, but complementary information regarding chemical properties of EPS. Multiphoton confocallaser microscopy, coupled with fluorescent probes, is used to probe "intact" natural samples. Quantitative imaging can determine spatial variability and intensities of cellular and extracellular activities. Nuclear magnetic resonance (nmr) is used to probe EPS for specific functional groups, which may be involved in sorption processes. Alterations of the groups by UVB irradiance or oxidative damage effect specific changes in EPS ligands. We attempt to quantitate these effects. Raman spectroscopy is used to "fingerprint" laboratoryEPS. Then natural EPS, is examined for the presence of fingerprints; and to what degree fingerprints have been altered. Such techniques provide important complementary information for characterizing physical/chemical properties of extracellular polymers.
 
Day: Monday, Feb. 1
Time: 04:00 - 04:15pm
Location: Sweeney Center
 
Code: SS17MO0400S