Improving the homologous recombination efficiency of by grafting heterologous component from

The oleaginous non-conventional yeast has enormous potential as a microbial platform for the synthesis of various bioproducts. However, while the model yeast has very high homologous recombination (HR) efficiency, non-homologous end-joining is dominant in , and foreign genes are randomly inserted into the genome. Consequently, the low HR efficiency greatly restricts the genetic engineering of this yeast. In this study, RAD52, the key component of the HR machinery in , was grafted into to improve HR efficiency. The gene , whose deletion can result in a brown colony phenotype, was used as the reporter gene for evaluating the HR efficiency. The HR efficiency of strains before and after integrating the gene was compared using insets with homology arms of different length. The results showed that the strategy could achieve gene targeting efficiencies of up to 95% with a homology arm length of 1000 bp, which was 6.5 times of the wildtype strain and 1.6 times of the traditionally used disruption strategy. This study will facilitate the further genetic engineering of to make it a more efficient cell factory for the production of value-added compounds.