Cloning and high expression of Δ12- desaturase genes from Mucor circinelloides EIM-10

Δ12- desaturase plays an important role in the biosynthesis of linoleic acid in Mucor sp EIM- 10. To improve enzymatic on the Δ12- desaturase activity, a recombinant expression vector was constructed. The Δ12-desaturase gene was cloned by RT- PCR technology. The PCR products were ligated into p YES2.0 plasmid. And then the recombinant plasmid ( p YMD12) was transformed into Saccharomyces cerevisiae strain INVSc1 by lithium acetate method. To improve enzymatic activity, built- in promoter of p YES2.0 was replaced by GAP promoter, another new recombinant expression ( p YGAPMD12) were constructed in Saccharomyces cerevisiae strain INVSc1.Gas chromatography analysis showed that conversion efficiency of p YGAPMD12 was 69.172% and the conversion efficiency of p YMD12 was 36.401%. This paper was provided important reference for further stay of Δ12-desaturase.