A soluble delipidized (Na + K)-stimulated ATPase was obtained from rabbit kidney outer medulla by the use of sodium deoxycholate. The activity of this enzyme was stimulated ZO-fold to an activity of 100 to 120 pmoles of Pi per mg of protein per hour by either phosphatidylserine or phosphatidylglycerol. The effect of the fluidity of the hydrocarbon region of the phospholipid bilayers on this re-...

A soluble delipidized (Na + K)-stimulated ATPase was obtained from rabbit kidney outer medulla by the use of sodium deoxycholate. The activity of this enzyme was stimulated ZO-fold to an activity of 100 to 120 pmoles of Pi per mg of protein per hour by either phosphatidylserine or phosphatidylglycerol. The effect of the fluidity of the hydrocarbon region of the phospholipid bilayers on this re-...

We have investigated the relationship between function and molecular dynamics of both the lipid and the Ca-ATPase protein in sarcoplasmic reticulum (SR), using temperature as a means of altering both activity and rotational dynamics. Conventional and saturation-transfer electron paramagnetic resonance (EPR) was used to probe rotational motions of spin-labels attached either to fatty acid hydroc...

The use of accelerated temperature stability studies using the Arrhenius relationship is routine for estimating the stability of a drug at room temperature. Therefore, the acceleration method is used to determine the expiration date of dexamethasone aqueous formulation manufactured in Iran. A high-performance liquid chromatography (HPLC) method utilizing ultraviolet (UV) detection for dexa...

We report results from the molecular dynamics simulations of a binary colloidal mixture subjected to an external potential barrier along one spatial directions at low volume fraction, {\phi} = 0.2. The variations in asymmetry do not change smaller particles, showing Arrhenius diffusion. However, larger particles shows crossover sub-Arrhenius super-Arrhenius diffusion with temperatures and fract...

This paper draws attention to selected experiments on enzyme-catalyzed reactions that show convex Arrhenius plots, which are very rare, and points out that Tolman's interpretation of the activation energy places a fundamental model-independent constraint on any detailed explanation of these reactions. The analysis presented here shows that in such systems, the rate coefficient as a function of ...