A yeast cell suspension (60 ml containing 1 to 5 ml of
plasmid DNA) in a 0.2-cm sterile Bio-Rad cuvette was electroporated with a
Gene Pulser and a Pulse Controller (both obtained from Bio-Rad) set at 1.5 to
2.0 kV (the value varied from strain to strain), 25 mF, and 200 V. Authentic yeast
transformants were selected as described below