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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
1276
|
| pubmed:dateCreated |
1992-7-10
|
| pubmed:abstractText |
Studies of the interaction between actin and myosin subfragment 1 (S1) in solution have shown that the association reaction takes place in at least two steps. Initially the association is relatively weak to form a complex called the A state which can then isomerize to the R state. The rate and equilibrium constants for the isomerization have been measured and are shown to depend upon the nucleotide bound to the S1 ATPase site; with ATP bound the A state is preferred but as ATP is hydrolysed and the products are sequentially released then the complex gradually shifts to the A state. An extensive series of experiments have characterized the A-to-R isomerization both in solution and in contracting muscle fibres and have shown it to be closely associated with the key events in the ATP-driven contraction cycle: the conformational change from the A to the R state can be monitored by fluorescent probes on either actin or the nucleotide; the isomerization can be perturbed by increases in hydrostatic pressure; the actin-induced acceleration of the rate of product release from myosin is coupled to the A-to-R isomerization; tropomyosin may control actin and myosin interaction by controlling the isomerization step and finally pressure perturbations of contracting muscle fibres shows there to be a close coupling between the isomerization of acto.S1 and the force generating event of muscle contraction.
|
| pubmed:grant | |
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Apr
|
| pubmed:issn |
0962-8436
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
29
|
| pubmed:volume |
336
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
63-70; discussion 70-1
|
| pubmed:dateRevised |
2010-8-25
|
| pubmed:meshHeading | |
| pubmed:year |
1992
|
| pubmed:articleTitle |
The actomyosin ATPase: a two-state system.
|
| pubmed:affiliation |
Department of Biochemistry, School of Medical Sciences, University of Bristol, U.K.
|
| pubmed:publicationType |
Journal Article,
In Vitro,
Review,
Research Support, Non-U.S. Gov't
|