Fig. 3.

Metabolic engineering for folate bioproduction in A. gossypii. Increased availability of GTP for the biosynthesis of folate is achieved by reducing competing pathways: gene deletion of ADE12 and gene underexpression of RIB1. Boosting folate production is accomplished by gene overexpression of FOL genes. Switching metabolic flux towards either riboflavin production or folate production results in super yellow strains or light yellow strains, respectively. Dashed lines indicate multistep pathways; thin lines indicate reduction of metabolic flux; thick lines indicate increase of metabolic flux