Probing protein stabilization by glycerol using electrospray mass spectrometry

Area of Science:

• Biophysical Chemistry
• Analytical Chemistry
• Protein Science

Background:

• Understanding protein stability is crucial for drug development and biotechnology.
• Glycerol is a common cryoprotectant and stabilizer for proteins.
• Traditional methods for assessing protein stability can be complex and time-consuming.

Purpose of the Study:

• To demonstrate the utility of electrospray ionization mass spectrometry (ESI-MS) for monitoring protein stabilization.
• To investigate the effects of glycerol on protein conformation using ESI-MS.
• To analyze protein structural changes induced by various denaturing conditions in the presence and absence of glycerol.

Main Methods:

• Utilized electrospray ionization mass spectrometry (ESI-MS) with a heated turbo ion-spray interface.
• Analyzed mass-to-charge (m/z) distributions of proteins (lysozyme and cytochrome c).
• Applied thermal, acidic, and acetonitrile-induced denaturation protocols.

Main Results:

• ESI-MS successfully monitored the stabilizing effect of glycerol on proteins in solution.
• Glycerol protected proteins against unfolding induced by heat, acid, and acetonitrile.
• Minor conformational changes in lysozyme upon glycerol addition were detected, suggesting a slightly compressed structure.

Conclusions:

• ESI-MS is a powerful tool for studying protein stabilization and conformational dynamics.
• Glycerol demonstrably stabilizes protein structures against various denaturing agents.
• ESI-MS can detect subtle structural alterations and partially folded protein states.