Identification of two forms of myosin light chain kinase in turkey gizzard

Open Access
Publisher Website
Google Scholar
Abstract
Two forms of myosin light chain kinase from turkey gizzard are separable by ion‐exchange chromatography. One is the well‐characterized 13 000 M r enzyme. Purification of the second form by affinity chromatography on calmodulin‐Sepharose showed it to consist of two polypeptide chains of M r 136 000 and 141 000. This form of the enzyme required Ca2+ and calmodulin for activity, was specific for the M r 20 000 light chain of myosin, and appeared to phosphorylate the same site on the light chain as the M r 130 000 enzyme. The low‐M r gizzard kinase may be a proteolytic fragment of a higher‐M r species or these may represent different isoenzymes.