J. Biol. Chem., Vol. 259, Issue 24, 15007-15009, Dec, 1984
6-Tridecylresorcylic acid, a novel ATPase inhibitor that blocks the contractile apparatus of skeletal muscle proteins
M Kobayashi, A Kajiwara, M Takahashi, Y Ohizumi, N Shoji and T Takemoto
6-Tridecylresorcylic acid (TRA) isolated from a primula Lysimachia japonica
Thunb. inhibited contraction of myofibrils, superprecipitation of myosin B,
and ATPase activities of myosin and actomyosin prepared from rabbit
skeletal muscle in a dose-dependent manner. The IC50 values in molarity of
TRA were as follows: myosin (K+,EDTA)-ATPase, 3.5 X 10(- 6); myosin
Ca2+-ATPase, 3.5 X 10(-5); and actomyosin Mg2+-ATPase, 1.6 X 10(-5). The
inhibition of ATPase activity of myofibrils by TRA was virtually reversed
by washing with the fresh saline solution. Kinetic analysis of inhibitory
effects of TRA suggests that the inhibition of (K+,EDTA)-ATPase activity of
myosin or subfragment-1 is parabolic noncompetitive. TRA had no effect on
alkaline phosphatase and choline acetyltransferase activities. TRA may
provide a useful chemical tool for the study of the molecular mechanisms of
actin-myosin contractile systems.