- Author
- Year
- 2011
- Title
- Monitoring selectivity in kinase-promoted phosphorylation of densely packed peptide monolayers using label-free electrochemical detection
- Journal
- Langmuir
- Volume | Issue number
- 27 | 17
- Pages (from-to)
- 11212-11221
- Document type
- Article
- Faculty
- Faculty of Science (FNWI)
- Institute
- Van 't Hoff Institute for Molecular Sciences (HIMS)
- Abstract
-
This paper describes remarkably high sensitivities in the label-free detection of kinase-promoted phosphorylation for 14 different peptide substrates on electrode-immobilized monolayers (gold or nitride) using serine/threonine kinases PKA, PKC, and CaMK2. Peptide substrates were preselected using 33P-labeling in a microarray of 1024 substrates. The three most active peptides (A1-A3, C1-C3, and M1-M3) were investigated using electrochemical impedance spectroscopy (EIS) and ion-sensitive field effect transistors (ISFETs). Some of the peptide substrates, for example, the PKC-specific substrate PPRRSSIRNAH (C1), showed a remarkably high sensitivity in the EIS-based sensor measurements. Our studies revealed that this high sensitivity is primarily due to the monolayer’s packing density. Nanoscopic studies demonstrated a distinct disordering of the C1-monolayer upon phosphorylation, while phosphatase-promoted dephosphorylation regenerated the highly ordered peptide monolayer. As a matter of fact, the initial surface packing of the peptide monolayer mainly determined the level of sensitivity, whereas electrostatic repulsion of the redox-active species was found to be much less important.
- URL
- go to publisher's site
- Language
- English
- Note
- PT: J; TC: 0; UT: WOS:000294373300107
- Persistent Identifier
- https://hdl.handle.net/11245/1.350160
Disclaimer/Complaints regulations
If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library, or send a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible.