Fig. 1
From: A novel strategy for l-arginine production in engineered Escherichia coli
Major metabolic pathways associated with l-arginine biosynthesis in E. coli and metabolic engineering approaches applied to overproduce l-arginine. Dotted gray arrows with 
indicate the deletion of the relevant genes. Black thick arrows indicate increased fluxes by directly overexpressing the corresponding genes. Black dashes indicate the negative feedback inhibition mechanisms. The role of ArgR repressor regulation on l-arginine production is shown in the gray box. Abbreviations: G6P glucose 6-phosphate, F6P fructose 6-phosphate, DHAP dihydroxyacetone phosphate, G3P glyceraldehyde 3-phosphate, n-acetyl-glu-P n-acetylglutamate-phosphate, n-acetyl-sa n-acetylglutamate-semialdehyde, CPS carbamoyl phosphate