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Polymerization of Actin Induced by a Molar Excess of ATP in a Low Salt Buffer
Author(s) -
Ikkai Takamitsu,
Kondo Hiroshi
Publication year - 2000
Publication title -
iubmb life
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.132
H-Index - 113
eISSN - 1521-6551
pISSN - 1521-6543
DOI - 10.1080/713803584
Subject(s) - depolymerization , polymerization , actin , dilution , chemistry , tris , size exclusion chromatography , adenosine triphosphate , salt (chemistry) , molar concentration , buffer (optical fiber) , molar , chromatography , nucleotide , molar ratio , biophysics , polymer chemistry , biochemistry , polymer , organic chemistry , enzyme , catalysis , biology , telecommunications , paleontology , physics , computer science , gene , thermodynamics
The polymerization of actin induced by dilution has previously been reported, where a 1000‐fold molar excess of ATP over actin resulted when actin was diluted to 4.0 microg/ml in low salt buffer A (0.1 mM ATP, 0.1 mM CaCl2, 2 mM Tris‐HCl, pH 8.0, 5 mM 2‐ mercaptoethanol, 1 mM NaN3). Filaments formed by the addition of ATP to a 1000‐fold molar excess over actin in buffer B (0.1 mM CaCl2, 2 mM Tris‐HCl, pH 8.0, 1 mM NaN3) were then separated by gel‐filtration. When ATP was removed from these filaments using Dowex‐1, depolymerization occurred. Thus, the reversible polymerization induced by the dilution of actin or by addition of ATP can be ascribed to the binding of ATP at the low affinity site of actin.