Acetyl coenzyme A carboxylase: filamentous nature of the animal enzymes.

Acetyl coenzyme A carboxylases purified from several animal tissues exist as enzymatically active polymeric filaments of high molecular weight and have simillar electron microscopic, hydrodynamic, and catalytic properties. These filaments reversibly dissociate into inactive protomers of uniform size. Their re-assembly into catalytically active filaments is promoted by the presence of an allosteric activator.