[Comparative study of solubilized and membrane-bound acetylcholinesterase of sarcolemma].

Comparative kinetic studies of membrane-bound and solubilized sarcolemmal acetylcholinesterase reveal some difference in concentration-activity curves. A deviation from normal Michaelis-Menten kinetics is found in case of membrane-bound acetylcholinesterase. The solubilization of sarcolemma by a solution of high ionic strength or by sonication normalizes the reaction kinetics. It is shown that the amount of SH-groups in intact sarcolemma available for DTNB in the presence of sodium dodecyl sulphate, is about twice of that in the absence of sodium dodecyl sulphate. In case of the solubilized fraction of sarcolemma (by a solution of high ionic strength or by sonication), the amount of SH-groups available for DTNB in the presence and in the absence of sodium dodecyl sulphate is similar.