Why is the E. coli lac Z gene used as a reporter gene in S. cerevisiae cells but not in E. coli cells?

The E. coli lac Z gene is used as a reporter gene in S. cerevisiae cells because the yeast lacks the lactose metabolism pathway, making it suitable for detecting lac Z expression. In contrast, E. coli naturally metabolizes lactose using the lac Z gene, so it is not ideal for use as a reporter gene in the same species.