A new time-resolved fluorescence spectrophotometer was developed to provide rapid collection and analysis of macromolecular size, decay lifetimes, and spectra. The instrument was exploited to study protein associations (eg; active oligomerization; enzyme I dimerization; VSV spike protein/G aggregation. The system was modified to speed studies of conformational change in proteins (eg; thioredoxin sulfhydryl reduction/oxidation and folding. Model tryptophyl-related systems (melatonin, serotonin, trp peptides, copper and nickel quenchings) were examined. The latter will provide us a better understanding of the origins of heterogeneous protein decay signals. Fluorescence data analysis methods were developed and published that associate spectra with macromolecular size, lipid domain viscosity, and surface proton transfer. """"""""Global analysis"""""""" methods were also developed to quantitate macromolecule axial ratios and to study proteins and lipids exhibiting distributed decay. The instrument was modified to provide emission scanning under computer control, so we can revisit glutamine synthetase and other proteins. The laser-based fluorescence instrument was also combined with state-of-the-art microwave instrumentation (with Dr. Rafferty, WRAIR) to provide an entirely new measurement capability: dielectric resonant motions in macromolecules. Several other new laser fluorescence measuring instruments were designed and are being prototyped.
Showing the most recent 10 out of 12 publications