Show simple item record

dc.contributor.authorTersariol, Ivarne Luis dos Santos [UNIFESP]
dc.contributor.authorDietrich, Carl Peter [UNIFESP]
dc.contributor.authorNader, Helena Bonciani [UNIFESP]
dc.identifier.citationEuropean Journal of Biochemistry. New York: Springer Verlag, v. 245, n. 1, p. 40-46, 1997.
dc.description.abstractHeparin and its enzymatic fragments, prepared by degradation of heparin with heparinase from Flavo-bacterium heparinum, were capable of inhibiting the actomyosin-ATPase activity obtained from striated and smooth vascular muscles. Heparin did not inhibit the myosin-ATPase activity in absence of actin. the results show that heparin changes the step of ATP hydrolysis of the complex actomyosin-ATPase by uncoupling the conformational transition on the myosin-head induced by actin upon the nucleotide-binding site. This mechanism is cooperative and dependent on conformational states of actomyosin complex which in turn is regulated by ATP and calcium levels. It was observed that in the presence of ATP, actin does not compete with heparin for binding to myosin showing that heparin and actin have different binding sites on myosin. the binding of heparin and ATP is cooperative suggesting that the nucleotide binding leads to an exposition of a second heparin-binding site. However, in the absence of ATP, actin competes with heparin for a binding site on the myosin. These results strongly suggest that in the weakly binding state of actin to myosin, the binding of heparin is powerful and in the rigor state its binding is decreased.en
dc.relation.ispartofEuropean Journal of Biochemistry
dc.rightsAcesso aberto
dc.subjectmyosin ATPaseen
dc.subjectheparin and hemorrhagic activityen
dc.subjectinhibition of actomyosinen
dc.titleUncoupling of actomyosin adenosinetriphosphatase by heparin and its fragmentsen
dc.contributor.institutionUniversidade Federal de São Paulo (UNIFESP)
dc.description.affiliationUNIFESP, ESCOLA PAULISTA MED, DISCIPLINA BIOL MOL, BR-04044020 São Paulo, BRAZIL
dc.description.affiliationUnifespUNIFESP, ESCOLA PAULISTA MED, DISCIPLINA BIOL MOL, BR-04044020 São Paulo, BRAZIL
dc.description.sourceWeb of Science

Files in this item


There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record