Cryogenic Sample Loading into a Magic Angle Spinning Nuclear Magnetic Resonance Spectrometer that Preserves Cellular...

Area of Science:

• Biophysics
• Structural Biology
• Analytical Chemistry

Background:

• Dynamic nuclear polarization (DNP) significantly boosts nuclear magnetic resonance (NMR) sensitivity, especially at low temperatures.
• This enhanced sensitivity allows for the study of molecules at very low concentrations.
• The application of DNP in magic angle spinning (MAS) NMR opens possibilities for in-cell structural biology.

Purpose of the Study:

• To describe a detailed protocol for preparing and cryogenically transferring frozen mammalian cells for DNP MAS NMR.
• To address the challenge of cellular integrity loss during sample preparation for DNP MAS NMR.

Main Methods:

• Development of a sample preparation protocol for mammalian cells.
• Implementation of a cryogenic transfer method for DNP MAS NMR.
• Utilizing dynamic nuclear polarization (DNP) with magic angle spinning (MAS) NMR spectroscopy.

Main Results:

• A method for preserving cellular integrity during sample preparation for DNP MAS NMR was established.
• Successful cryogenic transfer of frozen mammalian cells into a MAS NMR spectrometer was achieved.
• The protocol facilitates the study of macromolecules at endogenous levels within their native cellular environment.

Conclusions:

• The developed protocol enables high-sensitivity in-cell structural biology using DNP MAS NMR.
• This method overcomes previous limitations related to cellular integrity during sample handling.
• It paves the way for studying biological systems at the molecular level in their native states.