Related Experiment Video
Updated: Jun 28, 2026

Mass Spectrometric Approaches to Study Protein Structure and Interactions in Lyophilized Powders
Published on: April 14, 2015
Vibrational study of phosphate modes in GDP and GTP and their interaction with magnesium in aqueous solution
1Department of Physics, City College, City University of New York, New York 10031, USA.
Abstract:
Raman and infrared spectra were examined for guanosine 5'-diphosphate (GDP) and guanosine 5'-triphosphate (GTP) in aqueous solution. The vibrational modes were assigned on the basis of isotopic frequency shifts and relative intensities in the Raman and infrared spectra. The observed frequency shifts on 18O isotope labeling made it possible to identify the bands from each phosphate group (alpha, beta, gamma). Frequency shifts were observed as Mg2+ complexes with GDP and GTP. The results suggested that Mg2+ binds to GDP in a bidentate manner to the alpha, beta P[symbol: see text]O bonds and in a tridentate manner to the alpha, beta and gamma P[symbol: see text]O bonds of Mg.GTP. The results indicate that structure of Mg2+ coordinated to GTP in aqueous solution differs somewhat to that found for Mg.ATP.
Related Concept Videos
Phosphorylation
During phosphorylation, protein kinases transfer the terminal phosphate group of ATP to specific amino acid side chains of substrate proteins. Serine, threonine, and tyrosine are the most commonly...
Protein Kinases and Phosphatases
Protein kinases
Many proteins in the cell are regulated by phosphorylation, the addition of a phosphate group. A family of enzymes called kinases...
GTPases and their Regulation
Large G-proteins, also known...
Activation and Inactivation of G Proteins
IP3/DAG Signaling Pathway
Introduction to Electrolytes
Role of Sodium
One...

