Compared with the Mut~+, the Mut~s-hFL transformants showed higher expression level with less coloring contamination in the product and easier purification for hFL.

• 与Mut~+型相比，Mut~s转化子在含营养和色素较少的BMM培养基中即有高表达，且表达产物杂蛋白少，易于纯化。