Insight into the mechanism of fast movement of myosin from Chara corallina.

Chara myosin, two-headed plant myosin belonging to class XI, slides F-actin at maximally 60 microm s(-1). To elucidate the mechanism of this fast sliding, we extensively investigated its mechanochemical properties. The maximum actin activated ATPase activity, Vmax, was 21.

Biochemical properties of ordinary and dark muscle myosin from carp skeletal muscle.

Two types of myosin isolated from ordinary (fast) and dark (slow) muscles of carp were examined by ATPase and in vitro motility assays. Vmax of the ATPase activity and sliding velocity of ordinary myosin showed 1.6 and 1.

Partial specific volume and adiabatic compressibility of G-actin depend on the bound nucleotide.

We determined the partial specific volume and partial specific adiabatic compressibility of either ATP- or ADP-bound monomeric actin in the presence of Ca(2+) by measuring the density of and sound velocity in a monomeric actin solution at 18 degrees C. The partial specific volume of ATP-bound monomeric actin, equal to 0.744 cm(3)/g, which is exceptionally high among globular proteins, was reduced to 0.