Premium
Protein Matrix Elasticity Determined by Fluorescence Anisotropy of Its Tryptophan Residues ¶
Author(s) -
Zentz Christian,
Glandières JeanMarie,
Moshni Sadok,
Alpert Bernard
Publication year - 2003
Publication title -
photochemistry and photobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.818
H-Index - 131
eISSN - 1751-1097
pISSN - 0031-8655
DOI - 10.1562/0031-8655(2003)0780098rcpmed2.0.co2
Subject(s) - tryptophan , chemistry , anisotropy , elasticity (physics) , fluorescence , matrix (chemical analysis) , fluorescence anisotropy , protein dynamics , biophysics , glycerol , analytical chemistry (journal) , crystallography , protein structure , biochemistry , chromatography , thermodynamics , physics , amino acid , optics , biology , membrane
Rotational motions of Trp residues embedded within human hemoglobin matrix have been measured by using their steady‐state fluorescence anisotropy. The mean square angular displacement θ 2 of Trp residues, depending on the temperature, can be expressed bywhere W is the thermal energy acting on the Trp residues and C the resilient torque constant of the protein matrix. To study the external medium influencing the protein dynamics, comparative experiments were made with protein in aqueous buffer and in the presence of 32% glycerol. The data show that between 5°C and 25°C, external medium acts on the protein matrix elasticity.