Intramolecular dynamics and functional activity of proteins
Mazhul', V.M.; Zaĭtseva, E.M.; Shcherbin, D.G.
Biofizika 45(6): 965-989
2000
ISSN/ISBN: 0006-3029 PMID: 11155248 Document Number: 517259
The intramolecular dynamics of proteins in solution and in biological membranes and cells was analyzed by the method of tryptophan phosphorescence at room temperature. Changes in protein internal dynamics in solution upon varying the pH, ionic strength and temperature of solution, transition into the apoform, binding of substrates, allosteric activator, and inhibitors, upon limited proteolysis, thermoinactivation, association, and refolding were demonstrated. The functional significance of low-frequency equilibrium fluctuations of the protein structure in enzyme catalysis was shown. A new phosphorescence method for investigation of millisecond internal dynamics of membrane proteins was developed. Functionally significant shifts of the internal dynamics of membrane proteins were detected upon the action of biologically active substances, physiologically moderate factors, under oxidative stress, and in cancer and autoimmune diseases. The role of protein internal dynamics in the process of intracellular signaling is discussed.