Proof for the biosynthetic conversion of L-[indole-15N]tryptophan to [10-15N]anthramycin using (13C, 15N) labelling in conjunction with 13C-NMR and mass spectral analysis.
Using 13C-NMR and mass spectral analysis we have demonstrated that the N-10 nitrogen of anthramycin is biosynthetically derived from the indole-nitrogen of tryptophan. Our experimental approach was to bring a 15N atom, which is derived from L-[indole-15N]tryptophan, and a 13C atom which is derived from DL-[1-13C]tyrosine, into adjacent positions of anthramycin. From resonance intensities and 13C-15N spin-spin coupling in the 13C-NMR spectrum of didehydroanhydroanthramycin, a derivative of anthramycin, we could then determine the 13C enrichment at C-11 and the proportion of 13C bonded to 15N at N-10. These results when combined with mass spectral analysis and isotopic dilution measurements proved that the indole nitrogen of tryptophan was completely retained at N-10 of anthramycin.
D000596:Amino Acids / Q000378:metabolism; D000876:Anthramycin / Q000096:biosynthesis*; D001570:Benzodiazepinones / Q000096:biosynthesis*; D001711:Biotransformation; D005285:Fermentation; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D009587:Nitrogen Isotopes; D014364:Tryptophan / Q000378:metabolism*
D000596:Amino Acids; D001570:Benzodiazepinones; D009587:Nitrogen Isotopes; D000876:Anthramycin; D014364:Tryptophan