The stability test of transformants obtained by electroporation. Transformants were transferred to a gridded YPD agar plate (left panel, YPD-P0), passaged onto YPD solid medium for 5 consecutive times (YPD-P5), and examined for their resistance to the appropriate antibiotic on selective agar medium. After fifth passage, transformants with spotty growth on the selective medium (shown here YPD+NAT-P5 on the right panel) compared to that on nonselective YPD medium (YPD-P5 on the middle panel) were considered unstable. Transformants that grew robustly on the selective medium as they grew on nonselective medium were considered stable (pointed by the white triangles on the right image on YPD+NAT). This particular original master plate (YPD-P0) shown here have two colonies turned red, indicating of an ade2 mutation (pointed by red arrows in the left image). These red transformants grew robustly on the YPD+NAT medium, indicating that these transformants are stable and the construct likely has been integrated into the genome and disrupted the ADE2 gene.