Quantifying protein-carbohydrate interactions using liquid sample desorption electrospray ionization mass spectrometry

• Author(s) / Creator(s)

  • Klassen, John S.
  • N. Kitova, Elena N.
  • Yao, Yuyu
  • Shams-Ud-Doha, Km
  • Daneshfar, Rambod

• The application of liquid sample desorption electrospray ionization mass spectrometry (liquid sample DESI-MS) for quantifying protein–carbohydrate interactions in vitro is described. Association constants for the interactions between lysozyme and β-D-GlcNAc-(1 → 4)-β-D-GlcNAc-(1 → 4)-D-GlcNAc and β-D-GlcNAc-(1 → 4)-β-D-GlcNAc-(1 → 4)-β-D-GlcNAc-(1 → 4)-D-GlcNAc, and between a single chain antibody and α-D-Galp-(1 → 2)-[α-D-Abep-(1 → 3)]-α-D-Manp-OCH3 and β-D-Glcp-(1 → 2)-[α-D-Abep-(1 → 3)]-α-D-Manp-OCH3 measured using liquid sample DESI-MS were found to be in good agreement with values measured by isothermal titration calorimetry and the direct ESI-MS assay. The reference protein method, which was originally developed to correct ESI mass spectra for the occurrence of nonspecific ligand-protein binding, was shown to reliably correct liquid sample DESI mass spectra for nonspecific binding. The suitability of liquid sample DESI-MS for quantitative binding measurements carried out using solutions containing high concentrations of the nonvolatile biological buffer phosphate buffered saline (PBS) was also explored. Binding of lysozyme to β-D-GlcNAc-(1 → 4)-β-D-GlcNAc-(1 → 4)-D-GlcNAc in aqueous solutions containing up to 1× PBS was successfully monitored using liquid sample DESI-MS; with ESI-MS the binding measurements were limited to concentrations less than 0.02 X PBS.

• Date created

  2015

• Subjects / Keywords

  • Carbohydrates
  • Proteins
  • Liquid sample desorption electrospray ionization mass spectrometry
  • Affinity

• Type of Item

  Article (Published)

• DOI

  https://doi.org/10.7939/R3B27Q42R

• License

  © 2015 Yao, Y., Shams-Ud-Doha, K., Daneshfar, R., Kitova, E. N., & Klassen, J. S. This version of this article is open access and can be downloaded and shared. The original author(s) and source must be cited.