Premium
Heat denaturation of rabbit skeletal G‐actin in the presence of ATP
Author(s) -
Ikeuchi Yoshihide,
Iwamura Kazunori,
Suzuki Atsushi,
Muguruma Michio,
Ito Tatsumi,
Fukazawa Toshiyuki
Publication year - 1990
Publication title -
journal of the science of food and agriculture
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.782
H-Index - 142
eISSN - 1097-0010
pISSN - 0022-5142
DOI - 10.1002/jsfa.2740500302
Subject(s) - heavy meromyosin , actin , chemistry , polymerization , denaturation (fissile materials) , biophysics , atpase , adenosine triphosphate , electron microscope , fluorescence , viscosity , biochemistry , nuclear chemistry , enzyme , organic chemistry , polymer , biology , materials science , physics , composite material , quantum mechanics , optics
Heat treatments at pH 7‐5 induced the polymerisation of G‐actin without the addition of KCl or MgCl 2 . This heat‐induced polymerisation of G‐actin was accompanied by the splitting of ATP. The polymerised actin at 45°C could be depolymerised by dialysis against a solution containing ATP. Electron microscopic observation of actin showed that irregular filaments were formed after heat treatment at 45°C for 3h, and at 55°C small filamentous pieces were formed. The abilities of heavy meromyosin ATPase (EC 3.6.1.32) activation and ATP splitting of G‐actin were drastically impaired by heating to temperatures above 50°C. Studies of the temperature dependence of fluorescence and viscosity data also revealed that heat denaturation of G‐actin in the presence of ATP occurred steeply between 45°C and 55°C.