Length of myosin rod and its proteolytic fragments determined by electron microscopy

AbstractThe mean length of rabbit myosin chymotryptic rod in electron micrographs of unidirectionally shadowed preparations was 154 nm. Tryptic light meromyosin prepared from this rod had a mean length of 86 nm whereas long and short S2 measured 62 and 43 nm, respectively. The combined length of light meromyosin and long S2 appeared to be less than that of rod, which indicated that possibly some material was lost on digestion. Molecular lengths agreed with sedimentation equilibrium Mr values but were lower than those indicated by gel electrophoresis