Fig. 1From: Metabolic engineering of Escherichia coli BW25113 for the production of 5-Aminolevulinic Acid based on CRISPR/Cas9 mediated gene knockout and metabolic pathway modificationThe biosynthetic pathways of ALA in E. coli and the strategies for constructing the ALA producing strain. The shaded boxes indicate the genes that were knocked out. Red arrows indicate increased flux or activity by directly over-expressing the corresponding genes. Blue arrows indicate decreased flux or activity by knocking out the corresponding genes. Dotted boxes represent the corresponding metabolic pathwaysBack to article page