[Kinetic regularities and mechanisms of action of calix[4]arene C-99 on ATPase activity of myosin subfragment-1 of myometrium].

It has been shown that calix[4]arene C-99 inhibited myosin subfragment-1 ATPase of myometrium. This inhibition is noncompetitive as to ATP and Mg2+. At the same time, this compound reduces the seeming enzymatic hydrolysis maximum rate of nucleoside triphosphate with respect to ATP and Mg2+. With the help of computer design the interaction of mentioned calix[4]arene with myosin subfragment-1 of myometrium has been investigated. Several mechanisms involved in the calix[4]arene C-99 inhibition of myosin head ATPase were supposed and participation of hydrogen, hydrophobic and electrostatic interactions in these mechanisms was discussed.