Isolation and characterisation of the acetyl-CoA carboxylase gene from Aspergillus nidulans

The putative gene encoding acetyl-CoA carboxylase, accA, has been isolated from Aspergillus nidulans. This single-copy gene has an open reading frame (ORF) of 6864 bp and contains two small introns near the 5'-end. A short OR F upstream of the ATG start codon has been identified in this gene by RT-PC R. Based on sequence homology to acetyl-CoA carboxylases from other organis ms,putative biotin-, ATP-, HCO3-- and acetyl-CoA-binding sites have been as signed, Northern data and ACC enzyme-activity measurements from A. nidulans suggested that expression of accA was higher in media containing nitrate t han ammonia as a sole nitrogen source. Deletion of accA in A, nidulans was unsuccessful. The failure of A. nidulans to grow in the presence of the ACC -specific inhibitor, soraphen A, supplemented with C16-18 fatty acids sugge sted that ACC is an essential enzyme.