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Atomic force microscopy characterization of kinase-mediated phosphorylation of a peptide monolayer.

ABSTRACT: We describe the detailed microscopic changes in a peptide monolayer following kinase-mediated phosphorylation. A reversible electrochemical transformation was observed using square wave voltammetry (SWV) in the reversible cycle of peptide phosphorylation by ERK2 followed by dephosphorylation by alkaline phosphatase. A newly developed method for analyzing local roughness, measured by atomic force microscope (AFM), showed a bimodal distribution. This may indicate either a hole-formation mechanism and/or regions on the surface in which the peptide changed its conformation upon phosphorylation, resulting in increased roughness and current. Our results provide the mechanistic basis for developing biosensors for detecting kinase-mediated phosphorylation in disease.

SUBMITTER: Zhuravel R

PROVIDER: S-EPMC5107921 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Atomic force microscopy characterization of kinase-mediated phosphorylation of a peptide monolayer.

Zhuravel Roman R Amit Einav E Elbaz Shir S Rotem Dvir D Chen Yu-Ju YJ Friedler Assaf A Yitzchaik Shlomo S Porath Danny D

Scientific reports 20161114

We describe the detailed microscopic changes in a peptide monolayer following kinase-mediated phosphorylation. A reversible electrochemical transformation was observed using square wave voltammetry (SWV) in the reversible cycle of peptide phosphorylation by ERK2 followed by dephosphorylation by alkaline phosphatase. A newly developed method for analyzing local roughness, measured by atomic force microscope (AFM), showed a bimodal distribution. This may indicate either a hole-formation mechanism ...[more]

PMID: 27841355

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