Tryptophan phosphorescence of nascent and inactivated actin at the room temperature
Mazhul', V.M.; Zaĭtseva, E.M.; Shavlovskiĭ, M.M.; Kuznetsova, I.M.; Turoverov, K.K.
Biofizika 46(6): 988-996
2001
ISSN/ISBN: 0006-3029 PMID: 11771297 Document Number: 536632
Millisecond internal dynamics of native and inactivated actin from rabbit skeletal muscle was examined using room temperature phosphorescence. Inactivated actin was prepared by incubation of G-actin at 70 degrees C, by treatment with 4 M urea or 1.5 M guanidinium hydrochloride, renaturation from fully unfolded state or by Ca2+ ion removal. It was shown that inactivation of actin, irrespective of the denaturation procedure applied, leads to a sharp decrease of millisecond fluctuations of the protein structure. Restriction of the slow intramolecular mobility in inactivated actin can result from changes of the protein conformation and/or specific association of macromolecules.