Gene pacA(+) codes for the multiple active forms of P-i-repressible acid phosphatase in the mould Aspergillus nidulans

The acid phosphatase secreted by the biA1 strain of the mould Aspergillus n idulans was separated into at least nine isoforms by isoelectric focusing ( IEF). The components visualized by activity were predominantly acidic prote ins with isoelectric points ranging from pH 4.0 to 6.5. Almost the same iso forms were secreted by strains pabaA1 and palD8 biA1. Furthermore, the isof orms secreted by strain pacA1 biA1 were not visualized by staining after IE F, indicating that these isoforms are encoded by gene pacA. Treatment of th e secreted enzyme with endoglycosidase H also reduced the number of isoform s visualized by staining after IEF and enhanced the R-f (electrophoretic mo bility) value of this enzyme visualized after PAGE.