Phosphatase mutants in Aspergillus nidulans.

Three mutants at three different phosphatase loci produce inactive enzymes at 35 degrees C but partially or fully active enzynmes at 25 degrees C. Furthermore, a suppressor mutant (su5palA1) which restores alkaline phosphatase activity in the palA1 mtutant is an allele of palcC4, a mzutant with a simultaneous reduction in alkaline and acid phosphatase activity. These data suggest that the phosphataseproteins may be made up of two or more different polypeptide chains, and that some of the polypeptide chains are common to two or more of these enzymes.