Identification of Myosin in a Flowering Plant, Egeria densa1

Abstract

A myosin-like protein was extracted and partially purified from a flowering plant, Egeria densa. It had no p-nitrophenyl phosphatase activity, but exhibited EDTA(K⁺)-ATPase [EC 3.6.1.3] activity at high ionic strength. Its molecular weight as estimated by gel filtration was4–5×10⁵ The presence of a heavy chain (MW=about l·8×l0 was indicated by SDS-gel electrophoresis. Egeria myosin aggregated in an environment of low ionic strength and formed bipolar filaments. It bound with skeletal muscle F-actin with a periodicity of 40 nm.