TABLE 4. cAMP accumulates in a ΔpurH mutant.

cAMP levels were measured in WT and mutant strains of S. enterica by untargeted metabolomics (relative levels) or by a competitive enzyme-linked immunosorbent assay (ELISA). Cells were grown in minimal medium containing glucose, adenine and thiamine medium and harvested during early (ES) and/or late stationary (LS) phase (only harvested during ES for ELISA). Each experiment consisting of 3 biological replicates of each strain. Fold changes were the ratio of the average MS ion intensities between two strains.

^a p-values indicative of statistically significant differences are denoted by: **(<0.05), ***(<0.01).