Development of a pyrG Mutant of Aspergillus oryzae Strain S1 as a Host for the Production of Heterologous Proteins

• Published in: TheScientificWorld Vol. 2013; no. 2013; pp. 1 - 7
• Main Authors: Abu Bakar, Farah Diba, Illias, Rosli Md, Mahadi, Nor Muhammad, Rodzi, Mohd Rohaizad Mohd, Zheng, Yun, Storms, Reginald, Ling, Selina Oh Siew, Abdul Murad, Abdul Munir
• Format: Journal Article
• Language: English
• Published: Cairo, Egypt Hindawi Publishing Corporation 01.01.2013; Hindawi Limited; Wiley
• Subjects: Aspergillus; Aspergillus oryzae; Aspergillus oryzae - physiology; Biochemistry; Chromosomes; Deoxyribonucleic acid; DNA; Enzymes; Fungal Proteins - physiology; Fungi; Galactosidase; Gene expression; Gene mutations; Genetic aspects; Genetic engineering; Genetic Enhancement - methods; Genetic research; Genomes; Health aspects; Markers; Microbiological research; Mutagenesis; Mutagenesis, Site-Directed - methods; Mutants; Mutation; Organic chemistry; Orotidine-5'-Phosphate Decarboxylase - genetics; Plasmids; Protein Engineering - methods; Proteins; PyrG gene; Uridine; β-Galactosidase; United States > US
• ISSN: 2356-6140; 1537-744X; 1537-744X
• DOI: 10.1155/2013/634317

The ease with which auxotrophic strains and genes that complement them can be manipulated, as well as the stability of auxotrophic selection systems, are amongst the advantages of using auxotrophic markers to produce heterologous proteins. Most auxotrophic markers in Aspergillus oryzae originate from chemical or physical mutagenesis that may yield undesirable mutations along with the mutation of interest. An auxotrophic A. oryzae strain S1 was generated by deleting the orotidine-5′-monophosphate decarboxylase gene (pyrG) by targeted gene replacement. The uridine requirement of the resulting strain GR6 pyrGΔ0 was complemented by plasmids carrying a pyrG gene from either Aspergillus nidulans or A. oryzae. β-Galactosidase expression by strain GR6 pyrGΔ0 transformed with an A. niger plasmid encoding a heterologous β-galactosidase was at least 150 times more than that obtained with the untransformed strain. Targeted gene replacement is thus an efficient way of developing auxotrophic mutants in A. oryzae and the auxotrophic strain GR6 pyrGΔ0 facilitated the production of a heterologous protein in this fungus.