Construction Of Engineering Yeast Of Yarrowia Lipolytica To Improve The Yield Of γ-decalactone

y-Decalactone (GDL) which can exhibit creamy and fruity sensorial notes like peach and coconut is recognized as a safe food ingredient and additive in various fields. In this paper, the engineering yeast strains were constructed by disrupting the POX3and GUT2genes of the uracil auxotrophic mutant of Yarrowia lipolytica to increase the productivity of GDLThe Ura3gene used as the selectable marker in the disruption cassettes was cloned from Yarrowia lipolytica AS2.1405. The promoter, terminator and the direct repeat sequence of the gene POX3were amplified from the uracil auxotrophic mutant of Yarrowia lipolytica which is the initial strain in this paper. The three gene fragments were integrated with Ura3in the vector pSP72. The linearizing disruption cassette was transferred into the starting strain by electroporation and POX3gene was disrupted by homologous recombination. Use5-FOA plate to screen the positive clones of occurring second homologous recombination. Fermentation was carried out with the recombinant POX-T5and the productivity of GDL is3.373g/L which is2.53times of the starting strain.The distuption of GUT2was the same as the POX3, by using the Ura3as the selectable marker and amplifying the gene fragments by PCR. The GUT2disruption cassette was transferred into the starting strain by eletroporation and the positive clones GUT-T1were selected by twice screenings. Fermentation was carried out by using the recombinant GUT-T1and the productivity of GDL is1.3times of the initial strain.Finally, the GUT2disruption cassette was transferred into the recombinant POX-T5which used the same selectable marker gene to knock out the two target genes in the same strain without any foreign gene. In order to get higher GDL productivity, more screenings will be needed and the fermentation conditiongs need to be optimized.