2-O-(2-Aminoethyl)-myo-inositol 1,4,5-trisphosphate as a novel ligand for conjugation: physicochemical properties and synthesis of a new Ins(1,4,5)P(3) affinity matrix

• Published in: Biochemical and biophysical research communications Vol. 318; no. 2; pp. 444 - 452
• Main Authors: Riley, Andrew M, Dozol, Helene, Spiess, Bernard, Potter, Barry V L
• Format: Journal Article
• Language: English
• Published: United States 28.05.2004
• Subjects: Amines - chemistry; Biosensing Techniques - methods; Calcium - chemistry; Calcium - metabolism; Chromatography, Affinity; Hepatocytes - metabolism; Humans; Hydrogen-Ion Concentration; Inositol - chemistry; Inositol 1,4,5-Trisphosphate - analogs & derivatives; Inositol 1,4,5-Trisphosphate - chemical synthesis; Inositol 1,4,5-Trisphosphate - chemistry; Kinetics; Ligands; Models, Molecular; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular - methods; Phosphorus Isotopes; Potentiometry; Protein Binding; Protons
• ISSN: 0006-291X

2-O-(2-Aminoethyl)-Ins(1,4,5)P(3), (5), a novel derivative of the Ca(2+)-mobilising second messenger d-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)], was synthesised from myo-inositol. 5 was found to be a potent mobiliser of intracellular Ca(2+), and an Ins(1,4,5)P(3) affinity matrix synthesised from 5 was effective at selectively binding N-terminal fragments of the Ins(1,4,5)P(3) receptor containing the intact Ins(1,4,5)P(3) binding site. The microprotonation scheme for 5 was resolved and the related constants were determined in comparison with Ins(1,4,5)P(3) and another reactive Ins(1,4,5)P(3) analogue 1-O-(2-aminoethyl-1-phospho)-Ins(4,5)P(2), (2a), by potentiometric and NMR titration methods. The (31)P and (1)H NMR titration curves for compound 5 and Ins(1,4,5)P(3) are remarkably close, indicating analogous acid-base properties and intramolecular interactions for the two compounds. The 1-phosphate-modified Ins(1,4,5)P(3) derivative 2a, on the contrary, behaves as a bisphosphorylated rather than a trisphosphorylated inositol. Thus, 5 is a new reactive Ins(1,4,5)P(3) analogue of considerable potential for investigation of the chemical biology of Ins(1,4,5)P(3)-mediated cellular signalling.