Glutamine utilization in both the arginine-specific and pyrimidine-specific carbamoyl phosphate synthase enzymes of eurospora crassa.

Summary As glutamine-dependent carbamoyl phosphate synthetase (CPS) activity in some organisms is composed of a glutaminase and an ammonium-dependent CPS, CPS^- mutants in Neurospora crassa were examined for glutamine- and ammonium-dependent CPS activities. No evidence was found that the genetic location of these two functions were separable. This is discussed with reference to the close genetic proximity of the CPS_pyr and aspartate carbamoyl-transferase (ACT) structural gene (pyr-3) and the arg-2 gene which appears to specify a subunit responsible for glutamine utilisation in CPS_arg.Supported by Science Research Council Grant B/RG/2981