Orphan spin polarization: A catalyst for high-throughput solid-state NMR spectroscopy of proteins

Area of Science:

• Biophysical Chemistry
• Structural Biology
• Nuclear Magnetic Resonance Spectroscopy

Background:

• Magic angle spinning solid-state NMR (MAS ssNMR) is crucial for determining the structure of biomacromolecules that resist crystallization, such as membrane proteins and fibrils.
• Conventional multidimensional ssNMR methods are time-consuming, acquiring one experiment at a time and discarding valuable spin operators.
• Low sensitivity and resolution in protein samples necessitate lengthy acquisition times for ssNMR experiments.

Purpose of the Study:

• To develop novel multiple acquisition solid-state NMR methods for accelerated protein structure determination.
• To utilize discarded spin operators to enhance data acquisition efficiency in ssNMR.
• To reduce overall experimental time for multidimensional ssNMR studies of biomolecules.

Main Methods:

• Development of a family of experiments termed Polarization Optimized Experiments (POE).
• Utilization of orphan spin operators, typically discarded in classical NMR, for simultaneous acquisition.
• Implementation of three concatenation strategies: DUMAS, MEIOSIS, and MAeSTOSO for combining 2D and 3D experiments.
• Use of conventional probes and single-receiver spectrometers.

Main Results:

• Simultaneous acquisition of multiple 2D and 3D experiments is achieved using POE.
• Recovery and utilization of orphan spin operators lead to increased experimental efficiency.
• The DUMAS, MEIOSIS, and MAeSTOSO strategies enable the concatenation of various ssNMR experiments.
• Significant reduction in acquisition times for multidimensional ssNMR experiments is demonstrated.

Conclusions:

• The developed POE methods, including DUMAS, MEIOSIS, and MAeSTOSO, offer a significant advancement in ssNMR.
• These techniques enable the simultaneous acquisition of multiple experiments, drastically reducing experiment duration.
• This breakthrough provides new avenues for efficient structure determination of challenging biomacromolecules using ssNMR spectroscopy.