BioChip Journal

, 5:199 | Cite as

Analysis of chemical/biochemical conversions on gold microparticles using MALDI-TOF MS

Original Research

Abstract

Chemical and biochemical analyses on solid supports are now in common because of the feasibility and simplicity of the process. For example, post-translational modifications of proteins such as phosphorylation, acetylation, and glycosylation have been assayed on several types of solid supports, mostly on 2-dimensional formats. Use of 3-dimensional solid supports, such as gold microparticles in this study, is beneficial over 2-dimensional biochips in terms of larger active surface areas and easier handling protocol. In this report, we present analyses of chemical conversions as well as enzymatic conversions on gold microparticles using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). For immobilization of enzyme substrates, gold microparticles, which presented organic functional groups, were subjected to a series of chemical reactions encompassing amide coupling and Michael addition. The resulting particles were then treated with enzymes. Direct analysis of the resulting products on microparticles by MALDI-TOF MS was performed without additional labeling steps, called SAMDI (self-assembled monolayers for MALDI). The mass spectra clearly showed chemical modifications and enzymatic conversions of peptide substrates on gold microparticles. We expect that our method can be used routinely in biological research, such as enzyme inhibitor assays, and development of substrate peptide of enzymes. We believe that the combination of gold microparticles with MALDI-TOF MS will provide an efficient analytical platform for use in various biochemical studies.

Keywords

Gold microparticles Kinase Mass spectrometry Monolayers Peptidase 

References

  1. 1.
    Min, D.-H., Su, J. & Mrksich, M. Profiling Kinase Activities by Using a Peptide Chip and Mass Spectrometry. Angew. Chem. Int. Ed. 116, 6099–6103 (2004).Google Scholar
  2. 2.
    Halling, P.J., Ulijn, R.V. & Flitsch, S.L. Understanding Enzyme Action on Immobilised Substrates. Curr. Opin. Biotechnol. 16, 385–392 (2005).CrossRefGoogle Scholar
  3. 3.
    Kim, Y.-P. et al. Protein Kinase Assay on Peptide-conjugated Gold Nanoparticles by Using Secondary-Ion Mass Spectrometric Imaging. Angew. Chem. Int. Ed. 46, 6816–6819 (2007).CrossRefGoogle Scholar
  4. 4.
    Inamori, K. et al. Optimal Surface Chemistry for Peptide Immobilization in On-Chip Phosphorylation Analysis. Anal. Chem. 80, 643–650 (2008).CrossRefGoogle Scholar
  5. 5.
    Gurard-Levin, Z.A., Kim, J. & Mrksich, M. Combining Mass Spectrometry and Peptide Arrays to Profile the Specificities of Histone Deacetylases. ChemBioChem 10, 2159–2161 (2009).CrossRefGoogle Scholar
  6. 6.
    Li, J., Nayak, S. & Mrksich, M. Rate Enhancement of an Interfacial Biochemical Reaction through Localization of Substrate and Enzyme by an Adaptor Domain. J. Phys. Chem. B 114, 15113–15118 (2010).CrossRefGoogle Scholar
  7. 7.
    Gooding, J.J., Mearns, F., Yang, W. & Liu, J. Self-Assembled Monolayers into the 21st Century: Recent Advances and Applications. Electroanalysis 15, 81–96 (2003).CrossRefGoogle Scholar
  8. 8.
    Yeo, W.-S. & Mrksich, M. Electroactive Substrates that Reveal Aldehyde Groups for Bio-Immobilization. Adv. Mater. 16, 1352–1356 (2004).CrossRefGoogle Scholar
  9. 9.
    Mrksich, M. Mass Spectrometry of Self-Assembled Monolayers: A New Tool for Molecular Surface Science. ACS Nano 2, 7–18 (2008).CrossRefGoogle Scholar
  10. 10.
    Bounichou, M. et al. Self-assembled monolayer-assisted mass spectrometry. J. Mater. Chem. 19, 8032–8039 (2009).CrossRefGoogle Scholar
  11. 11.
    Lee, J.R. et al. Mass Spectrometry Signal Amplification Method for Attomolar Detection of Antigens Using Small-Molecule-Tagged Gold Microparticles. Angew. Chem. Int. Ed. 47, 9518–9521.Google Scholar
  12. 12.
    Seo, H. et al. Facile Method for Development of Ligand-Patterned Substrates Induced by a Chemical Reaction. Chem. Eur. J. 17, 5804–5807 (2011)CrossRefGoogle Scholar
  13. 13.
    Lee, B. et al. RNA Polymerase Activity Assay on Biochips: Correlation between Template DNA Density and RNA Synthesis. Bull. Korean Chem. Soc. 31, 2107–2109 (2010).CrossRefGoogle Scholar
  14. 14.
    Mrksich, M. & Whitesides, G.M. Using self-assembled monolayers that present oligo(ethylene glycol) groups to control the interactions of proteins with surfaces. ACS Symp. Ser. 680, 361–373 (1997).CrossRefGoogle Scholar

Copyright information

© The Korean BioChip Society and Springer-Verlag Berlin Heidelberg  2011

Authors and Affiliations

  1. 1.Department of Bioscience of BiotechnologyKonkuk UniversitySeoulKorea

Personalised recommendations