Extended Data Figure 7. porA is important for phenylacetate and 4-OH-phenylacetate production, but not indoleacetate.

Resting cell suspensions of wild-type and porA mutant C. sporogenes were prepared at a fourfold higher cell density (for example, 1/20 culture volume), and incubated with phenylalanine, tyrosine, tryptophan (red) or indolepyruvate (green) for 1 h at 37 °C. Cells were then collected by centrifugation and the arylacetates were detected in the supernatant by LC-MS/MS. The absence of a peak indicates a defect in the conversion of the indicated substrate to the corresponding arylacetate. Representative chromatograms from n = 3 biological replicates are shown.