Suppression of active cross-bridge motions of isolated thick myofilaments in suspension by phenylmethylsulfonyl fluoride

Abstract

Studies of photoelectron count autocorrelation function of light scattered from suspensions of thick filaments of Limulus telson muscle and scallop striated adductor muscle reveal that Ca 2+ can activate cross-bridge motions of these isolated filaments. By treating suspensions of activated filaments with phenylmethylsulfonyl fluoride (PMSF), we can suppress active cross-bridge motions but not affect the Ca 2+-dependent ATPase activity.