a, sngl#4 biosynthesis was abolished in pah-1(syb3596);tph-1(mg280) and bas-1(ad446) but not tph-1(mg280) or pah-1(syb3601) mutants. b, Abundances of serotonin derivatives in two tph-1 alleles, tph-1(mg280) and tph-1(n4622), grown in parallel replicates. c, Relative abundances of serotonin derivatives in tph-1(n4622) endo-metabolome samples. d, Relative abundances of serotonin derivatives in cat-2(e1112) endo-metabolome samples. e, Scheme for quantitation of free serotonin via derivatization. f, g, Relative abundances of neurotransmitters dopamine (f) and tyramine (g) in WT, tph-1(mg280), tph-1(n4622), pah-1(syb3601), and pah-1(syb3596);tph-1(mg280) endo-metabolomes. Data in b (n = 3), c (n = 6), f and g (tph-1(mg280): n = 8, tph-1(n4622): n = 8, pah-1(syb3601): n = 7, pah-1(syb3596);tph-1(mg280): n = 4, bas-1(ad446): n = 4) represent biologically independent experiments and bars indicate mean ± s.d., p-values calculated via unpaired, two-tailed t-test with Welch correction, comparing mutant animals and WT. h, ESI+ ion chromatograms for m/z 221.0920 for bas-1(ad446) mutant, pah-1(syb3596);tph-1(mg280) double mutant, and WT endo-metabolomes as well as a 2 μM 5-HTP synthetic standard and co-injection with WT endo-metabolome. i, Enlargement of ESI+ ion chromatograms for m/z 221.0920 for bas-1(ad446), pah-1(syb3596);tph-1(mg280) double mutant, and WT endo-metabolomes as well as 50 nM synthetic standard of 5-HTP. Neither of the shown endo-metabolome chromatograms shows a significant peak for 5-HTP.