Engineered Fungus Thermothelomyces thermophilus Producing Plant Storage Proteins.

An efficient Agrobacterium -mediated genetic transformation based on the plant binary vector pPZP-RCS2 was carried out for the multiple heterologous protein production in filamentous fungus Thermothelomyces   thermophilus F-859 (formerly Myceliophthora   thermophila F-859). The engineered fungus Th.   thermophilus was able to produce plant storage proteins of Zea   mays (α-zein Z19) and Amaranthus   hypochondriacus (albumin A1) to enrich fungal biomass by valuable nutritional proteins and improved amino acid content. The mRNA levels of z19 and a1 genes were significantly dependent on their driving promoters: the promoter of tryptophan synthase (P trpC ) was more efficient to express a1 , while the promoter of translation elongation factor (P tef ) provided much higher levels of z19 transcript abundance. In general, the total recombinant proteins and amino acid contents were higher in the P tef -containing clones. This work describes a new strategy to improve mycoprotein nutritive value by overexpression of plant storage proteins.