FIG 4.

¹⁵N-labeling dynamics of nucleotides, amino acids, and biosynthetic intermediates following feruloyl amide treatment. Nitrogen incorporation into purine and pyrimidine biosynthetic pathways is inhibited by phenolic amides. Exponential-phase E. coli cultures exposed to 5.5 mM feruloyl amide for 5 min were switched into ¹⁵NH₄Cl. The data represent the average of two biological replicates. Incorporation of ¹⁵N into glutamine, glutamate, and other amino acids was minimally affected (A), while that into nucleotides and intermediates in pyrimidine biosynthesis was strongly inhibited (B), by feruloyl amide. Abbreviations: FBP, fructose-1,6-bisphosphate; Gln, glutamine; Glu, glutamate; Val, valine; Asp, aspartate; Phe, phenylalanine; Tyr, tyrosine; Dho, dihydroorotate; Oro, orotate.