Hyperpolarized MAS NMR of unfolded and misfolded proteins

Unfolded proteins and protein folding studied by NMR.

Preparation of biological macromolecules in the pure state requires that cells be disrupted, releasing and mixing the contents. Only the most stable and highly structured molecules can survive in the cellular “soup”, which contains proteases and nucleases that would be tightly controlled and sequestered in a normal living cell. Thus, as long as “activity” of polypeptides had to be measured by c...

Hyperpolarized xenon for NMR and MRI applications.

Nuclear magnetic resonance (NMR) spectroscopy and imaging (MRI) suffer from intrinsic low sensitivity because even strong external magnetic fields of ~10 T generate only a small detectable net-magnetization of the sample at room temperature (1). Hence, most NMR and MRI applications rely on the detection of molecules at relative high concentration (e.g., water for imaging of biological tissue) o...

Double-Quantum MAS NMR Spectroscopy

Exploring surfaces and cavities in lipoxygenase and other proteins by hyperpolarized xenon-129 NMR.

This paper presents an exploratory study of the binding interactions of xenon with the surface of several different proteins in the solution and solid states using both conventional and hyperpolarized (129)Xe NMR. The generation of hyperpolarized (129)Xe by spin exchange optical pumping affords an enhancement by 3-4 orders of magnitude of its NMR signal. As a result, it is possible to observe X...

NMR characterization of partially folded and unfolded conformational ensembles of proteins.

Studies of unfolded and partially folded proteins provide important insight into the initiation and process of protein folding. This review focuses on the use of nmr in characterization of ensembles of proteins that model the early stages of folding. Analysis of an ensemble includes description of the number of conformations, their structure, relative populations, interconversion rates, and dyn...