Abstract
The influence of divalent cations (Cd 2+ , Zn 2+ , Sr 2+ ) and staphylococcus protein A on the superprecipitation reaction of cardiac muscle actomyosin was investigated using methods of preparative protein chemistry, optical spectroscopy and mechanokinetic analysis. It was shown that the metal ions in the range of concentrations 0.1–5 mM inhibit the Mg 2+ -dependent SPP reaction of actomyosin cardiac muscle and alter the kinetic parameters of this process. It was revealed that protein A modulates superprecipitation dynamics decreasing the maximal value of optical density and time of its half-maximum achievement as well as starting and normalized superprecipitation rates. Thus, investigated factors are able to influence the actin myosin interaction changing their functional parameters of proteins from cardiomyocyte contractile complex. The kinetic characteristics of actomyosin superprecipitation are sensitive to the influence of physicochemical and pharmacological factors and can be used to study their influence on the molecular mechanisms of muscle contraction. Keywords: actomyosin, superprecipitation, kinetic parameters, metal ions, S. aureus protein A, cardiac muscle.
Highlights
Muscle contraction-relaxation is a dynamic oscillatory process that consists of interrelated and interdependent physical and chemical reactions
Superprecipitation (SPP) reaction can be consider as a certain model system to investigate the structural organization and functional properties of muscles actomyosin complex because the process of muscle contraction is associated namely with the formation of actomyosin complex and its subsequent conformational changes due to the energy released as a result of ATP hydrolysis by myosin [9, 14]
The superprecipitation of actomyosin is generally accepted to be simulate the phenomenon of muscle contraction in vitro
Summary
Muscle contraction-relaxation is a dynamic oscillatory process that consists of interrelated and interdependent physical and chemical reactions. The muscle contraction study can either accent on the properties of individual protein components of muscle to reconstruct from them mechanochemical model systems simulating the contractile process or reproduce the structural and functional state actomyosin complex during the reaction SPP. SPP is the process of myosin aggregates’ compaction with actin filaments due to ATP hydrolysis, which occurs in the presence of such aggregates in suspensions, sediments and actomyosin gels [16] This model system may be used to investigate several properties of the muscle contractile apparatus (actin-myosin interaction and its regulation, regularities of selfassembly of contractile systems, etc.) as well as the influence of different physical, chemical and pharmacological factors. Our aim consisted in the investigation of myocardium actomyosin SPP reaction changes induced some divalent metal ions and immunologically active substances of Staphylococcus aureus
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
