The functional unit of the arom conjugate in Neurospora

The functional unit of arom polyenzyme conjugate of Neurospora crassa was determined by analysis of radiation inactivation of each of the five activities in the conjugate. The functional targets for all five enzymes were in close agreement with the value of 300,000 obtained by conventional hydrodynamic procedure for the native dimeric structure. These data indicate that at least 95% of the functional enzyme system in crude extracts exists in a dimeric form and that both polypeptide chains of the homodimer are required for full activity of each of the five enzymes.