CONVERSION OF 17O/18O LABELLED δ-(L-α-AMINOADIPYL)-L-CYSTEINYL-D-VALINE TO 17O/18O LABELLED ISOPENICILLIN IN A CELL-FREE EXTRACT OF CEPHALOSPORIUM ACREMONIUM. A STUDY BY 17O-NMR SPECTROSCOPY AND MASS SPECTROMETRY.

Article abstract of DOI:10.1016/S0040-4020(01)91867-8

δ-(L-α-Amino<1,1,6-¹⁷O/¹⁸O>-adipyl)-L-cystinyl-D-valine was converted into isopenicillin N in cell-free extracts of Cephalosporium acremonium with no loss of ¹⁷O/¹⁸O label as shown by 17O NMR spectroscopy and mass spectrometry.Incubation of unlabelled tripeptide in a cell-free system containing ¹⁷O/¹⁸O enriched water produced isopenicillin N with no incorporation of ¹⁷O/¹⁸O.