Measuring Protein–Ligand Binding by Hyperpolarized Ultrafast NMR

Abstract

Protein−ligand interactions can be detected by observing changes in the transverse relaxation rates of the ligand upon binding. The ultrafast NMR technique, which correlates the chemical shift with the transverse relaxation rate, allows for the simultaneous acquisition of R 2 for carbon spins at different positions. In combination with dissolution dynamic nuclear polarization (D-DNP), where the signal intensity is enhanced by thousands of times, the R 2 values of several carbon signals from unlabeled benzylamine are observable within a single scan. The hyperpolarized ultrafast chemical shift-R 2 correlated experiment separates chemical shift encoding from the readout phase in the NMR pulse sequence, which allows it to beat the fundamental limit on the spectral resolution otherwise imposed by the sampling theorem. Applications enabled by the ability to measure multiple relaxation rates in a single scan include the study of structural properties of protein−ligand interactions.

Ultrafast Nuclear Magnetic Resonance as a Tool to Detect Rapid Chemical Change in Solution

“…Some examples have gone further by using these types of experiments to detect physically or chemically changing hyperpolarized molecules. For example, the target benzylamine was hyperpolarized using dDNP to boost its 13 C NMR signals by a factor of 4,500 to 5,800-fold . The binding of this target to the enzyme trypsin was then studied using ultrafast NMR by recording a series of T 2 relaxation experiments that correlate spatially encoded chemical shift with T 2 relaxation in experiments that take milliseconds per scan.…”

Two-Dimensional Laplace NMR Reconstruction through Deep Learning Enhancement

“…It plays a vital role in organic molecular structure determination, chemical composition assignment, and dynamic analysis. Specifically, Laplace NMR − extends the capabilities of conventional Fourier NMR by providing additional information on diffusion and relaxation processes related to molecular dynamics and spin interactions. − However, the extraction of diffusion coefficients and relaxation times requires appropriate data processing algorithms, such as inverse Laplace transform (ILT) . Compared to conventional Fourier transform (FT), ILT is notably intricate and time-consuming, primarily due to the ill-posed nature of ILT problems. , Two-dimensional (2D) Laplace NMR, and even multidimensional Laplace NMR, can provide more detailed information than the one-dimensional (1D) counterpart.…”

Rapid Protein–Ligand Affinity Determination by Photoinduced Hyperpolarized NMR

“…However, these methods add instrumental complexity, limiting scalable adoption. Furthermore, the hardware complexity challenges the experimental repeatability required for the quantitative analysis in K D determination. − …”

“…Furthermore, the hardware complexity challenges the experimental repeatability required for the quantitative analysis in K D determination. 19 − 22 …”