The step-size distance in muscle contraction: properties and estimates.
The step-size distance in muscle contraction is obtained using the step-size distance equation z = u/n, where z is the step-size distance, u is the actin filament velocity and n is the ATPase rate of splitting. In a previous study a step-size distance of about 17 A at no load was determined for intact frog muscle. Some properties of the step-size equation are described. We have now made estimates of the step-size distance z for a variety of muscles using existing physiological and biochemical data in the literature. The estimates are listed in Tables 1 and 2. We find that the step-size distances are clustered in the range 13-17 A for nearly all muscles.
Worthington
C R
CR
Carnegie-Mellon University, Pittsburgh, PA 15213, USA.
Elliott
G F
GF
D000199:Actins / Q000502:physiology; D000205:Actomyosin / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D001001:Anura; D003386:Brachyura; D008954:Models, Biological; D009119:Muscle Contraction / Q000502:physiology*; D018485:Muscle Fibers, Skeletal / Q000502:physiology; D011817:Rabbits; D012518:Sarcomeres / Q000737:chemistry / Q000502:physiology
D000199:Actins; D000205:Actomyosin; D000251:Adenosine Triphosphatases