Oct 23, 2013 – NMR Topical Group Meeting

The North Jersey ACS NMR Topical Group proudly presents its October monthly meeting at Rutgers CABM on Wednesday, October 23, 2013.  [ register ][raw]

This meeting is sponsored by Bruker BioSpin

Featured Speakers

Talk I

“General Overview of New Products For 2013”

George Anastasi,
Regional sales manager of Bruker BioSpin, Inc.

Talk II

“Recent advances in NMR spectroscopy of encapsulated proteins & nucleic acids dissolved in low viscosity fluids”

Prof. Josh Wand,
Johnson Research Foundation and Department of Biochemistry & Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia

Abstract for Talk II:

Solution NMR spectroscopy is a powerful technique to study protein structure and dynamics on multiple timescales and in many contexts. Sample preparation is often the key ingredient that enables otherwise very difficult studies of complex macromolecular systems. Some time ago we introduced the idea of using solutions of proteins encapsulated within the protective aqueous core of a reverse or inverted micelle and dissolved in low viscosity fluids as a means to overcome the “slow tumbling” problem presented by large, soluble proteins. Since then several advantageous properties of the reverse micelle particle have been used to promote studies of integral and anchored membrane proteins, soluble proteins and nucleic acids of marginal stability as well as investigations of various aspects of protein biophysics such as cold denaturation, protein hydration and protein motion.

Despite this, the approach has not been generally adopted by the NMR community. To make this reverse micelle encapsulation approach more accessible, we have developed an optimized reverse micelle surfactant system. Comprised of the nonionic 1-decanoyl-rac-glycerol and the zwitterionic lauryldimethylamine-N-oxide (10MAG/LDAO), this mixture is found to faithfully encapsulate a diverse set of proteins ranging up to 80 kDa in size and having a broad spectrum of electrostatic properties. Extensive chemical shift analyses indicate that encapsulation conditions that maintain high structural fidelity can be directly found. A clear advantage of 10MAG/LDAO is the active decrease of molecular reorientation time for encapsulated macromolecules larger than ˜20 kDa leading to improved signal-to-noise.

The properties of 10MAG/LDAO are also found to be very favorable for solution NMR studies of lipidated proteins. New and efficient strategies for optimization of encapsulation conditions have also been developed. 10MAG/LDAO performs well in both the low viscosity pentane and ultra-low viscosity liquid ethane and should serve as a general platform for initiating solution NMR studies of proteins and nucleic acids. In a parallel effort, it has been realized that reverse micelle solutions potentially offer a route to implement dynamic nuclear polarization enhancement of protein resonances by avoiding the dielectric heating generally associated with standard aqueous samples. Initial results will be presented. Supported by NSF and the NIH.