Coupling of nonpolymerizable monomeric actin to the F-actin binding region of the myosin head.
Polymerizations of skeletal G-actin induced by salt and myosin subfragment 1 (S-1) were suppressed by reaction of G-actin with m-maleimidobenzoyl-N-hydroxysuccinimide ester. The G-actin derivative, containing few intramolecular crosslinks and a free maleimide group, was covalently coupled in solution to the S-1 heavy chain. The resulting complex could no longer bind to F-actin. The SH-1 and SH-2 thiols of S-1 were not involved in the complexation and the covalent link was shown to be exclusively on the 50-kDa segment of the S-1 heavy chain. The specific conjugation of the two proteins followed formation of a reversibly associated pyrophosphate-sensitive binary complex which was characterized by different approaches. Potentially, these complexes may be useful in developing the crystallography of actin-bound S-1.
Bettache
N
N
Centre de Recherches de Biochimie Macromoléculaire du Centre National de la Recherche Scientifique, Unviersité de Montpellier, France.
Bertrand
R
R
Kassab
R
R
D000199:Actins / Q000378:metabolism*; D000818:Animals; D004591:Electrophoresis, Polyacrylamide Gel; D007700:Kinetics; D008970:Molecular Weight; D009132:Muscles / Q000378:metabolism; D009218:Myosins / Q000378:metabolism*; D010446:Peptide Fragments / Q000032:analysis; D011485:Protein Binding; D011817:Rabbits; D014357:Trypsin
D000199:Actins; D010446:Peptide Fragments; D014357:Trypsin; D009218:Myosins