The effect of low ATP concentrations on relaxation in the myosin regulated myofibrils from scallop
- PMID: 2940259
- DOI: 10.1007/BF01753411
The effect of low ATP concentrations on relaxation in the myosin regulated myofibrils from scallop
Abstract
Troponin-tropomyosin-regulated myofibrils show a significant increase in ATPase activity and contract in the absence of calcium when the ATP concentration falls significantly below the saturation level. By contrast, the ATPase of the myosin-regulated myofibrils of scallop striated muscle was not activated in the absence of calcium when the ATP concentration was lowered to 10mM. Nevertheless, a very small fraction of crossbridges were active at 10mM ATP resulting in very slow myofibrillar shortening. In contrast to the behaviour of rabbit contractile proteins there was no correlation between myofibrillar shortening and ATP induced turbidity changes of actomyosin taken from scallop.
Similar articles
-
Myofibrillar ATPase activity and mechanical performance of skinned fibres from rabbit psoas muscle.J Physiol. 1994 Jan 15;474(2):303-17. doi: 10.1113/jphysiol.1994.sp020023. J Physiol. 1994. PMID: 8006817 Free PMC article.
-
Observations on the interaction of calcium and hydrogen ions on ATP hydrolysis by the contractile elements of cardiac muscle.Recent Adv Stud Cardiac Struct Metab. 1975;5:273-80. Recent Adv Stud Cardiac Struct Metab. 1975. PMID: 242044
-
Reaction intermediates of myosin ATPase from scallop adductor muscles: nonidentical two-headed structure of striated adductor muscle myosin.J Biochem. 1982 Oct;92(4):1151-62. doi: 10.1093/oxfordjournals.jbchem.a134031. J Biochem. 1982. PMID: 6217199
-
Why choose myofibrils to study muscle myosin ATPase?J Muscle Res Cell Motil. 2003;24(2-3):139-48. doi: 10.1023/a:1026045328949. J Muscle Res Cell Motil. 2003. PMID: 14609025 Review.
-
Chemomechanical coupling in actomyosin system: an approach by in vitro movement assay and kinetic analysis of ATP hydrolysis by shortening myofibrils.Adv Biophys. 1991;27:237-57. doi: 10.1016/0065-227x(91)90023-7. Adv Biophys. 1991. PMID: 1836709 Review.
Cited by
-
Cooperativity of the calcium switch of regulated rabbit actomyosin system.Mol Cell Biochem. 1981 Feb 26;35(1):11-5. doi: 10.1007/BF02358183. Mol Cell Biochem. 1981. PMID: 6452574