In order to improve the optimum temperature of lipases, The Penidilum expansuin lipase (PEL) gene was mutated by site-directed mutagenesis using overlap extension PCR technique.

• 利用重叠延伸PCR法对扩展青霉碱性脂肪酶(PEL)基因作了体外定点突变，获得了最适作用温度有所提高的突变体。