Cloned ß-galactosidase gene of Escherichia coli is expressed in the yeast Saccharomyces cerevisiae.

The expression of the lacZ gene of E. coli in S. cerevisiae has been studied. The enzymatic activity coded by the lacZ gene in E. coli, β-galactosidase, is detectable in yeast cells harboring a chimeric plasmid carrying the gene. On the basis of size and immunological criteria, no difference was detected between the Coli-in-yeast β-galactosidase and the E. coli enzyme.