Session WOA. There are 3 abstracts in this session.



Session: Biomolecular 2, time: 08:30-09:10

Mapping protein aggregation landscapes by NMR   


Peter Wright
The Scripps Research Institute, La Jolla, CA
Many human diseases are associated directly with aggregation of extracellular proteins, leading to formation of toxic oligomers and deposition of insoluble amyloid fibrils. For globular proteins, the process is initiated by local unfolding of the native structure to form aggregation-prone intermediates. Despite their key role in amyloidogenesis, little is currently known about the structure of amyloidogenic intermediates because of their strong propensity to aggregate. Solution NMR provides a unique and powerful approach for mapping the kinetic aggregation landscape and characterizing the structure of transient intermediates. Applications of real-time 19F NMR and CPMG relaxation dispersion to characterize the kinetic aggregation pathways and aggregation-prone intermediates of wild type and pathogenic variants of human transthyretin will be described

Session: Biomolecular 2, time: 09:10am-09:50am

Elucidating Protein Structure and Folding Using Novel Long-Range Distance Solid-State NMR


Mei Hong
MIT, Cambridge, MA
            Two approaches to increase the distance reach of solid-state NMR from ~5 Å to ~2 nm will be presented. The first uses 19F as the probe and measures 19F-19F, 13C-19F and 1H-19F distances by a combination of spin diffusion and dipolar recoupling techniques under fast MAS (25-55 kHz). The second approach is proton-mediated 15N-13C and 13C-13C dipolar recoupling where pulsed spin-lock is used to make these experiments robust and sensitive to distances up to ~1 nm. These techniques are used to determine the cholesterol binding site in the influenza A M2 protein, the interhelical packing of influenza B virus M2, and the β-sheet packing of a novel amyloid fibril formed by the anti-hypoglycemia drug glucagon.
 

Session: Biomolecular 2, time: 09:50am-10:30am

Solid-state NMR applied to bacterial and human cells: Concepts & applications


Siddarth Narasimhan; Reinier Damman; Yanzhang Luo; Shengi Xiang; Alessandra Lucini Paioni; Johan van der Zwan; Marc Baldus
Bijvoet Ctr for Biomolecular Res., Utrecht Univ., Utrecht, Netherlands
Increasing evidence suggests that the highly complex and dynamic environment of bacterial and human cells imposes critical control on cellular functions which are difficult to mimic under in vitro conditions. Complementary to high-resolution light microscopy and electron tomography, in-cell solution-state NMR can track such structural and dynamical interactions at the most detailed, i.e., atomic level, provided that the molecular units tumble rapidly.
 
Cellular solid-state NMR (ssNMR), on the other hand, provides increasing possibilities to probe molecular structure in bacterial and human cell preparations largely irrespective of molecular size. In our contribution we discuss novel preparative as well as NMR-based hybrid concepts that allow for the study of proteins and (membrane)protein complexes in-situ.