Vmax (s-1) . | . | . | . | Km (μmol l-1) . | . | . | . | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Myosin . | . | Chimera . | . | Myosin . | . | Chimera . | . | ||||||
10 °C-acclimated carp | 1.8 | Loop 1-10 | 0.80 | 10 °C-acclimated carp | 2.7 | Loop 1-10 | 1.1 | ||||||
Loop 2-10 | 0.95 | Loop 2-10 | 0.7 | ||||||||||
30 °C-acclimated carp | 1.1 | Loop 1-30 | 0.80 | 30 °C-acclimated carp | 2.9 | Loop 1-30 | 0.8 | ||||||
Loop 2-30 | 0.68 | Loop 2-30 | 0.6 | ||||||||||
Wild type | 0.71 | Wild type | 0.9 |
Vmax (s-1) . | . | . | . | Km (μmol l-1) . | . | . | . | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Myosin . | . | Chimera . | . | Myosin . | . | Chimera . | . | ||||||
10 °C-acclimated carp | 1.8 | Loop 1-10 | 0.80 | 10 °C-acclimated carp | 2.7 | Loop 1-10 | 1.1 | ||||||
Loop 2-10 | 0.95 | Loop 2-10 | 0.7 | ||||||||||
30 °C-acclimated carp | 1.1 | Loop 1-30 | 0.80 | 30 °C-acclimated carp | 2.9 | Loop 1-30 | 0.8 | ||||||
Loop 2-30 | 0.68 | Loop 2-30 | 0.6 | ||||||||||
Wild type | 0.71 | Wild type | 0.9 |
Mg2+-ATPase activity was measured at 20 °C.
Myosins were prepared from fast skeletal muscle of carp acclimated to 10 and 30 °C (Chaen et al.,1996).
Chimeric myosins were prepared from Dictyostelium discoideumbackbone with loop 1 sequences from carp 10 °C- (loop 1-10) and 30°C-type S1 (loop 1-30) and with loop 2 sequences from carp 10 °C-(loop 2-10) and 30 °C-type S1 (loop 2-30).
Vmax, maximum initial velocity; Km,myosin affinity to actin.