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Updated: Oct 7, 2026

PIP-on-a-chip: A Label-free Study of Protein-phosphoinositide Interactions
10:58

PIP-on-a-chip: A Label-free Study of Protein-phosphoinositide Interactions

Published on: July 27, 2017

Contributions by ionic and steric features of ligands to their binding with phosphorylcholine-specific immunoglobulin

L G Bennett, C P Glaudemans

    Biochemistry
    |July 24, 1979
    PubMed

    The murine myeloma IgA H-8 Fab' fragment which exhibits a binding specificity for phosphorylcholine was assayed for its ability to bind with a number of charged ligands. Monitoring of the ligand-induced changes of protein fluorescence provided a fast and accurate method of determining the equilibrium binding constants. The binding data along with fluorescence spectral properties of the protein permitted an assessment of the relative importance of some binding parameters as well as an evaluation of certain ionic and steric contributions made by ligands exhibiting significant binding affinity for the antibody fragment. Among the conclusions reached is that the dielectric of the binding site microenvironment is important in determining the strength of binding and that hydrophobic groups surrounding a quaternary cationic ligand are important in creating an appropriate binding site of low dielectric value.

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