Fig. 4

Aggregate metabolomics data and representative analyses. a Heat map of pyridine nucleotide pools in acetol-producing and non-producing E. coli strains (n = 5). b Specific changes in NAD(P) metabolite ratios. c Heat map of metabolite levels in acetol-producing E. coli strains (n = 5). d PCA score plot for metabolic profiling of acetol-producing and non-producing E. coli strains. e The corresponding loading plot illustrating metabolites that contributed to the separation on PC1 and PC2. P values were obtained using a t test comparing optimized strains with the HJ06