预冷的1M山梨醇。若用抗性筛选方法，则立即加入1ml冰预冷的YPD/山梨醇。轻柔转移细胞悬液至一个无菌管中。
? 检查和记录脉冲参数。时间常数应接近5ms。电场强度可以通过实际电压（kV）
/电击杯间隙宽度（cm）获得。
? 用营养缺陷突变株进行互补筛选时，细胞应立即涂布至含有1M山梨醇的限定琼脂
平板（minimal agar plate）上。当用抗性筛选方法时，电转后的细胞在30℃振荡培养1-2小时；在含有1M山梨醇的YPD琼脂平板上，用适当的抗生素进行电穿孔细胞的培养。30℃培养72-96小时。
5.3 电转化所需溶液和试剂
? YPD/HEPES：100ml YPD培养基，20ml 1M HEPES，pH8.0。 ? 1M DTT：1.55g DTT，溶于8ml水，定容至10ml，过滤除菌。
? YPD/山梨醇：10g yeast extract，20g peptone，182.2g山梨醇，溶于700ml
水，定容至900ml。高压灭菌。临用前加入100ml无菌20%葡萄糖。
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