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PubMed · 141190

18O-exchange catalyzed by myosin, heavy meromyosin, heavy meromyosin subfragment 1 and their complexes with actin.

N S Panteleeva·N A Biró·E A Karandashov·F Fábián·I E Krasovskaya·N V Kuleva·E G Skvortsevich
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Abstract

Myosin, HMM and HMM S1 catalyze 18O-exchange between P1 and H218O of the medium at an intermediate stage of ATP hydrolysis ("intermediate 18O-exchange") in the presence of Mg2+. Natural complexes of actomyosin and acto-HMM S1 do not catalyze intermediate 18O-exchange but facilitate "direct" or "medium" 18O-exchange (KH2P18O4 in equilibrium H2O) even without ATP. Reconstituted complexes of actomyosin, acto-HMM, acto-HMM S1, PABC-HMM S1, congo-myosin and TNP-myosin do not catalyze direct 18O-exchange in the presence of Mg2+ and absence of ATP. From the data obtained a hypothetical sequence of phosphorylation and 18O-exchange reactions in myofibril action has been suggested.

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ActinsAdenosine TriphosphatasesAdenosine TriphosphateBinding SitesHydrolysisMyosin SubfragmentsMyosinsOxygen IsotopesJournal Article

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N S Panteleeva, N A Biró, E A Karandashov, F Fábián, I E Krasovskaya, N V Kuleva, E G Skvortsevich. 1977. 18O-exchange catalyzed by myosin, heavy meromyosin, heavy meromyosin subfragment 1 and their complexes with actin.. https://pubmed.ncbi.nlm.nih.gov/141190/

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