Untransformed S. cerevisiae S288C - whose genome contains AMD2 - fails to form colonies on acetamide, and acquires the ability to do so only when a heterologous acetamidase (YlAMD1) is supplied, indicating that the native S288C genome, which includes AMD2, does not supply growth-supporting acetamidase activity under these conditions. The readout is whole-genome growth and does not isolate AMD2 itself: the paper does not mention AMD2/YDR242W, and non-expression on this medium, limiting acetamide uptake, or sub-threshold activity would each be consistent with the control failing to grow.
"Control transformations failed to form colonies while YlAMD1-transformed cells gave rise to well-defined colonies on acetamide plates"