ABSTRACT
In the present study, the genome shuffling was used to improve lipase production of Penicillium expansum. A lipase producing mutant strain-Penicillium expansum FS8486 and a wild type of Aspergillus Tamarii FS-132 isolated from soil of a volcano in Xinjiang were used as the parental strains. After two rounds of genome shuffling, several elite daughter strains were screened. The lipase activity in one of the daughter strains was increased 317% over the starting strain FS8486. Comparisons of the morphology, RAPD (Random Amplification of Polymorphic DNA) polymorphism and the fatty acid compositions between the daughter and the parental strains suggested that the filial generation were generated by genome shuffling. In this study, the genome shuffling used successfully first time in eukaryotic microorganism and increases the production of the desired metabolite in short time, the study will be useful to spread the genome shuffling in eukaryotic microbial breeding.
Subject(s)
Aspergillus , Genetics , DNA Shuffling , Methods , Genetic Enhancement , Methods , Genome, Fungal , Genetics , Lipase , Genetics , Penicillium , Genetics , Random Amplified Polymorphic DNA TechniqueABSTRACT
Aspergillus oryzae is an important microorganism,which was widely used in the fields of food,brewing,pharmacy and fermentation industry etc and was termed as a generally regarded as safe(GRAS) organism by the United States Food and Drug Administration(FDA).The strategies for promoting the expression of homologous and heterologous proteins in Aspergillus oryzae were reviewed.Which included the usage of strong promoters,multicopies of coding genes,optimization of culture medium and overexpression of the hemoglobin domains(HBD) etc.Heterologous proteins were usually exhibited low expression in Aspergillus oryzae due to the degradation by the proteinases from host.Therefore,development of proteinase auxotrophic stains of Aspergillus oryzae as host is neccessary.In addition,fusion of the heterologous protein with a highly secreted protein of Aspergillus oryzae was an alternative way to prompt the expression of heterologous protein in Aspergillus oryzae.