Is a four-state model sufficient to describe actomyosin ATPase?
Four-[(1984), J. Biol. Chem. 259, 11908] and six-[(1985) Science 227, 999] state models have been proposed for actomyosin ATPase. A key experiment in deciding between these is whether or not there is a transient Pi burst at high actin. In the first, the cleavage and release of products rates are similar and the Pi burst is low; in the second, there are additional product complexes and the Pi burst is large. We reinvestigated the problem by carrying out burst experiments under the conditions in [(1985) Science 227, 999]. Since we find that the Pi burst at high actin is low, we conclude that the four-state model is sufficient to describe actomyosin ATPase.
Tesi
C
C
INSERM U128, CNRS, Montpellier, France.
Barman
T
T
Travers
F
F
D000199:Actins; D004735:Energy Transfer; D006868:Hydrolysis; D007700:Kinetics; D008962:Models, Theoretical; D009119:Muscle Contraction; D009132:Muscles / Q000201:enzymology; D009218:Myosins; D010446:Peptide Fragments
D000199:Actins; D010446:Peptide Fragments; C033025:actin subfragments; D009218:Myosins