ABSTRACT
We request funds to purchase an Optima Analytical Ultra Centrifuge (AUC) equipped with
interference optics from Beckman Inc. AUC is a powerful, first principle, technique that provides in
solution measurement of sample shape, size, and heterogeneity, in addition to measuring strengths of
bio-molecular interactions. AUC enables the researcher to perform native-condition characterization of
their protein of interest. The instrument will be housed in the Department of Biochemistry and Molecular
Biology at the Saint Louis University School of Medicine. The instrument will support basic research of
NIH-funded investigators at both the Medical School and in the College of Arts and Sciences. The AUC
will also be pivotal in assessing sample homogeneity for structural analysis using cryo-electron
microscopy. We describe projects from 4 major users with R01 NIH grants and 4 minor users that will
benefit from the requested instrumentation. The user projects span a range of biomolecular interactions
in DNA repair and recombination, blood clotting processes, protein aggregation in neurodegeneration,
immunothrombosis, regulation of protein translation, laminopathies and ubiquitination processes. All
these projects depend on biochemical analysis of the respective protein-protein and protein-substrate
complexes and the AUC will be instrumental in establishing their oligomeric and biomolecular
interaction properties. The new optima AUC will replace the existing older model ProteomeLab AUC
which is now 15 years old and well past the serviceable age. The optima AUC is also redesigned to
house the mechanical parts within the main chamber and possess much greater optical resolution and
data capture properties. More importantly, the optima AUC is compatible with fluorescence detection
capabilities that are currently under development. Training for the optima AUC will be primarily handled
by members of the Antony research group who have more than a decade of experience using the
instrumentation, sample preparation, and data analysis. Users (undergraduate & graduate students,
postdoctoral fellows, and research associates) will be trained to independently use the AUC and
instrument time will be determined using the existing scheduling system for departmental
instrumentation. A local advisory committee will provide oversight of the AUC and its operations. The
optima AUC will be an integral component of the biophysical instrumentation portfolio at Saint Louis
University and will have a significant impact on the NIH-funded research.