THE ASPERGILLUS-NIGER (FICUUM) APHA GENE ENCODES A PH 6.0-OPTIMUM ACID-PHOSPHATASE

We have used the Aspergillus niger (An) aphA gene as a probe and clone d the A. ficuum (Af) SRRC 265 gene encoding an extracellular pH 6.0-op timum acid phosphatase (APase6) from a genomic library. The identity o f the Af aphA gene was confirmed and its nucleotide (nt) sequence veri fied by comparing its deduced amino acid (aa) sequence to that of puri fied Af APase6. A comparison of the nt sequences of the An and Af gene s suggested that errors were made in the previously reported An aphA s equence. Several regions of the An aphA were resequenced and the mista kes corrected. With its nt sequence corrected, the An aphA is nearly i dentical to the cloned Af gene encoding APase6, and in 90.4% agreement in the coding regions. Both genes have three conserved introns and wh en translated, both nt sequences code for a polypeptide of 614 aa. The re is now evidence that the two cloned genes are homologous and code f or acid phosphatases that are 96% identical.