Localization of g₂ Light Chain in the Link between the Heads and Tail of Cardiac Myosin

Abstract

Cardiac myosin liberated 1.99 mol of acetate per mol after acid hydrolysis. The myosin subfragment-1, which cannot bind g₂ light chain, liberated 0.85-1.16 mol of acetate per mol. On the other hand, negligible amounts of acetate could be detected from g₁ and g₂ light chains. The acetates, which were measured by a microenzymic method, were derived from the acetylated N-terminal of the heavy chain. It was concluded that g₂ light chain is bound to the C-terminal region of subfragment-1, which is the link between the heads and tail of myosin.