Abstract
The myofibril suspension (in 0.16M KCI-40mM Tris-HCI, 7.5 or 0.16M KCI-40mM Tris-maleate, pH 5.8) of blue shark and tiger shark was kept at a fixed temperature in the range of 20-45°C with various concentrations of urea and measured for its Ca-ATPase activity with a lapse of time. In the presence of urea, myofibrillar Ca-ATPase of blue shark inactivated in two first order reactions with an early fast rate (kDf) and subsequently with a slow rate (kDs), whereas the inac-tivation of myofibrillar Ca-ATPase of tiger shark fitted by a single exponential with a rate of kD. Plotting the logarithm of rate constant against the concentration (M) of urea, a linear relation was thus obtained. The slope (D) of the graph of logarithm of rate constant versus urea (M) indicated that myofibrillar protein of blue shark was more susceptible to urea than that of tiger shark. By introducing an increase in the rate constant as a measure of accelerating effect on de-naturation of myofibrillar protein, multiplying effect by the presence of urea (0.3M), the fall in pH (from 7.5 to 5.8) and an increase in temperature was observed for both shark species.
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.
