Open AccessStudy of Tropomyosin Labelled with a Fluorescent Probe by Pulse Fluorimetry in Polarized Light
Author(s) -
WAHL Philippe,
TAWADA Katsuhisa,
AUCHET JeanClaude
Publication year - 1978
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1978.tb12464.x
Subject(s) - fluorescence , tropomyosin , chemistry , monomer , molecule , cysteine , fluorescence spectroscopy , fluorescence anisotropy , biophysics , polymer , photochemistry , actin , biochemistry , organic chemistry , biology , physics , membrane , enzyme , quantum mechanics
Tropomyosin has been labelled with a fluorescent probe N ‐iodoacetyl‐ N′ ‐(5‐sulfo‐1‐naphthyl)‐ethylenediamine which is presumed to bind preferentially to the unique reactive cysteine residue of the α chain. Anisotropy decay measurements show that tropomyosin monomer and polymer are flexible molecules. This flexibility decreases when troponin interacts with tropomyosin, and is partially restored by a micromolar concentration of Ca 2+ .