The Advanced Properties of Circularized MSP Nanodiscs Facilitate High-resolution NMR Studies of Membrane Proteins.

Membrane mimetics are essential for structural and functional studies of membrane proteins. A promising lipid-based system are phospholipid nanodiscs, where two copies of a so-called membrane scaffold protein (MSP) wrap around a patch of lipid bilayer. Consequently, the size of a nanodisc is determined by the length of the MSP.

Sensitivity-Enhanced Multidimensional Solid-State NMR Spectroscopy by Optimal-Control-Based Transverse Mixing Sequences.

Recently, proton-detected magic-angle spinning (MAS) solid-state nuclear magnetic resonance (NMR) spectroscopy has become an attractive tool to study the structure and dynamics of insoluble proteins at atomic resolution. The sensitivity of the employed multidimensional experiments can be systematically improved when both transversal components of the magnetization are transferred simultaneously after an evolution period. The method of preservation of equivalent pathways has been explored in solution-state NMR; however, it does not find widespread application due to relaxation issues connected with increased molecular size.

Maximizing efficiency of dipolar recoupling in solid-state NMR using optimal control sequences.

Dipolar recoupling is a central concept in the nuclear magnetic resonance spectroscopy of powdered solids and is used to establish correlations between different nuclei by magnetization transfer. The efficiency of conventional cross-polarization methods is low because of the inherent radio frequency (rf) field inhomogeneity present in the magic angle spinning (MAS) experiments and the large chemical shift anisotropies at high magnetic fields. Very high transfer efficiencies can be obtained using optimal control–derived experiments.

A single residue switch reveals principles of antibody domain integrity.

Despite their importance for antibody architecture and design, the principles governing antibody domain stability are still not understood in sufficient detail. Here, to address this question, we chose a domain from the invariant part of IgG, the C2 domain. We found that compared with other Ig domains, the isolated C2 domain is a surprisingly unstable monomer, exhibiting a melting temperature of ∼44 °C.