CLONING AND CHARACTERIZATION OF THE ADENOSYL PHOSPHOSULFATE KINASE GENE FROM ASPERGILLUS-NIDULANS

The sD gene of Aspergillus nidulans has been cloned by heterologous sc reening of rationally selected cosmids. Co-transformation of the sD50 mutant JMP1 confirmed the presence of a functional gene. Sequence anal ysis determined this gene to be 680 bp in length, containing a 59-bp i ntron and encoding a protein of 206 amino acids. A protein-sequence co mparison revealed a similarity to the C-terminal region of ATP sulphur ylase, the sC gene product. Further sequence comparison revealed diffe rences in a consensus sequence ATP-binding motif, indicating non-funct ionality of the APS kinase-like domain of ATP sulphurylase, and confir ms sD as the gene encoding APS kinase in A. nidulans.